xref: /illumos-gate/usr/src/cmd/devfsadm/disk_link.c (revision 90221f9148b67fdc90178b67f9600b7bd4e3bc7c)
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 2016 Toomas Soome <tsoome@me.com>
23  * Copyright 2016 Nexenta Systems, Inc.  All rights reserved.
24  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  */
27 
28 #include <devfsadm.h>
29 #include <stdio.h>
30 #include <strings.h>
31 #include <stdlib.h>
32 #include <limits.h>
33 #include <ctype.h>
34 #include <unistd.h>
35 #include <sys/int_fmtio.h>
36 #include <sys/stat.h>
37 #include <bsm/devalloc.h>
38 #include <sys/scsi/scsi_address.h>
39 #include <sys/libdevid.h>
40 #include <sys/lofi.h>
41 
42 #define	DISK_SUBPATH_MAX 100
43 #define	RM_STALE 0x01
44 #define	DISK_LINK_RE	"^r?dsk/c[0-9]+(t[0-9A-F]+)?d[0-9]+(((s|p))[0-9]+)?$"
45 #define	DISK_LINK_TO_UPPER(ch)\
46 	(((ch) >= 'a' && (ch) <= 'z') ? (ch - 'a' + 'A') : ch)
47 
48 #define	SLICE_SMI	"s7"
49 #define	SLICE_EFI	""
50 
51 #define	MN_SMI		"h"
52 #define	MN_EFI		"wd"
53 #define	ASCIIWWNSIZE	255
54 #if defined(__i386) || defined(__amd64)
55 /*
56  * The number of minor nodes per LUN is defined by the disk drivers.
57  * Currently it is set to 64. Refer CMLBUNIT_SHIFT (cmlb_impl.h)
58  */
59 #define	NUM_MINORS_PER_INSTANCE	64
60 #endif
61 
62 
63 extern int system_labeled;
64 
65 static int disk_callback_chan(di_minor_t minor, di_node_t node);
66 static int disk_callback_nchan(di_minor_t minor, di_node_t node);
67 static int disk_callback_blkdev(di_minor_t minor, di_node_t node);
68 static int disk_callback_wwn(di_minor_t minor, di_node_t node);
69 static int disk_callback_xvmd(di_minor_t minor, di_node_t node);
70 static int disk_callback_fabric(di_minor_t minor, di_node_t node);
71 static int disk_callback_sas(di_minor_t minor, di_node_t node);
72 static void disk_common(di_minor_t minor, di_node_t node, char *disk,
73 				int flags);
74 static char *diskctrl(di_node_t node, di_minor_t minor);
75 static int reserved_links_exist(di_node_t node, di_minor_t minor, int nflags);
76 static void disk_rm_lofi_all(char *file);
77 
78 
79 static devfsadm_create_t disk_cbt[] = {
80 	{ "disk", DDI_NT_BLOCK, NULL,
81 	    TYPE_EXACT, ILEVEL_0, disk_callback_nchan
82 	},
83 	{ "disk", DDI_NT_BLOCK_CHAN, NULL,
84 	    TYPE_EXACT, ILEVEL_0, disk_callback_chan
85 	},
86 	{ "disk", DDI_NT_BLOCK_BLKDEV, NULL,
87 	    TYPE_EXACT, ILEVEL_0, disk_callback_blkdev
88 	},
89 	{ "disk", DDI_NT_BLOCK_FABRIC, NULL,
90 		TYPE_EXACT, ILEVEL_0, disk_callback_fabric
91 	},
92 	{ "disk", DDI_NT_BLOCK_WWN, NULL,
93 	    TYPE_EXACT, ILEVEL_0, disk_callback_wwn
94 	},
95 	{ "disk", DDI_NT_BLOCK_SAS, NULL,
96 	    TYPE_EXACT, ILEVEL_0, disk_callback_sas
97 	},
98 	{ "disk", DDI_NT_CD, NULL,
99 	    TYPE_EXACT, ILEVEL_0, disk_callback_nchan
100 	},
101 	{ "disk", DDI_NT_CD_CHAN, NULL,
102 	    TYPE_EXACT, ILEVEL_0, disk_callback_chan
103 	},
104 	{ "disk", DDI_NT_BLOCK_XVMD, NULL,
105 	    TYPE_EXACT, ILEVEL_0, disk_callback_xvmd
106 	},
107 	{ "disk", DDI_NT_CD_XVMD, NULL,
108 	    TYPE_EXACT, ILEVEL_0, disk_callback_xvmd
109 	},
110 };
111 
112 DEVFSADM_CREATE_INIT_V0(disk_cbt);
113 
114 /*
115  * HOT auto cleanup of disks is done for lofi devices only.
116  */
117 static devfsadm_remove_t disk_remove_cbt[] = {
118 	{ "disk", DISK_LINK_RE, RM_HOT | RM_POST | RM_ALWAYS,
119 		ILEVEL_0, disk_rm_lofi_all
120 	},
121 	{ "disk", DISK_LINK_RE, RM_POST,
122 		ILEVEL_0, devfsadm_rm_all
123 	}
124 };
125 
126 DEVFSADM_REMOVE_INIT_V0(disk_remove_cbt);
127 
128 static devlink_re_t disks_re_array[] = {
129 	{"^r?dsk/c([0-9]+)", 1},
130 	{"^cfg/c([0-9]+)$", 1},
131 	{"^scsi/.+/c([0-9]+)", 1},
132 	{NULL}
133 };
134 
135 static char *disk_mid = "disk_mid";
136 static char *modname = "disk_link";
137 
138 /*
139  * Check if link is from lofi by checking path from readlink().
140  */
141 static int
142 is_lofi_disk(char *file)
143 {
144 	char buf[PATH_MAX + 1];
145 	char filepath[PATH_MAX];
146 	char *ptr;
147 	ssize_t size;
148 
149 	size = snprintf(filepath, sizeof (filepath), "%s/dev/%s",
150 	    devfsadm_root_path(), file);
151 	if (size > sizeof (filepath))
152 		return (0);
153 
154 	size = readlink(filepath, buf, sizeof (buf) - 1);
155 	if (size == -1)
156 		return (0);
157 	buf[size] = '\0';
158 	ptr = strchr(buf, '@');
159 	if (ptr == NULL)
160 		return (0);
161 	ptr[1] = '\0';
162 	if (strcmp(buf, "../../devices/pseudo/lofi@") != 0)
163 		return (0);
164 	return (1);
165 }
166 
167 /*
168  * Wrapper around devfsadm_rm_link() for lofi devices.
169  */
170 static void disk_rm_lofi_all(char *file)
171 {
172 	if (is_lofi_disk(file))
173 		devfsadm_rm_link(file);
174 }
175 
176 int
177 minor_init()
178 {
179 	devfsadm_print(disk_mid,
180 	    "%s: minor_init(): Creating disks reserved ID cache\n",
181 	    modname);
182 	return (devfsadm_reserve_id_cache(disks_re_array, NULL));
183 }
184 
185 static int
186 disk_callback_chan(di_minor_t minor, di_node_t node)
187 {
188 	char *addr;
189 	char disk[23];
190 	char *driver;
191 	uint_t targ = 0;
192 	uint_t lun = 0;
193 
194 	driver = di_driver_name(node);
195 	if (strcmp(driver, LOFI_DRIVER_NAME) != 0) {
196 		addr = di_bus_addr(node);
197 		(void) sscanf(addr, "%X,%X", &targ, &lun);
198 	} else {
199 		targ = di_instance(node);
200 	}
201 
202 	(void) snprintf(disk, sizeof (disk), "t%dd%d", targ, lun);
203 	disk_common(minor, node, disk, 0);
204 	return (DEVFSADM_CONTINUE);
205 
206 }
207 
208 static int
209 disk_callback_nchan(di_minor_t minor, di_node_t node)
210 {
211 	char *addr;
212 	char disk[10];
213 	uint_t lun;
214 
215 	addr = di_bus_addr(node);
216 	(void) sscanf(addr, "%X", &lun);
217 	(void) sprintf(disk, "d%d", lun);
218 	disk_common(minor, node, disk, 0);
219 	return (DEVFSADM_CONTINUE);
220 
221 }
222 
223 static int
224 disk_callback_blkdev(di_minor_t minor, di_node_t node)
225 {
226 	char *addr;
227 	char disk[DISK_SUBPATH_MAX];
228 	uint64_t eui64;
229 	uint_t lun = 0;
230 
231 	addr = di_bus_addr(node);
232 	(void) sscanf(addr, "w%016"PRIx64",%X", &eui64, &lun);
233 	(void) snprintf(disk, DISK_SUBPATH_MAX, "t%016"PRIX64"d%d", eui64, lun);
234 	disk_common(minor, node, disk, RM_STALE);
235 	return (DEVFSADM_CONTINUE);
236 }
237 
238 static int
239 disk_callback_wwn(di_minor_t minor, di_node_t node)
240 {
241 	char disk[10];
242 	int lun;
243 	int targ;
244 	int *intp;
245 
246 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, SCSI_ADDR_PROP_TARGET,
247 	    &intp) <= 0) {
248 		return (DEVFSADM_CONTINUE);
249 	}
250 	targ = *intp;
251 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, SCSI_ADDR_PROP_LUN,
252 	    &intp) <= 0) {
253 		lun = 0;
254 	} else {
255 		lun = *intp;
256 	}
257 	(void) sprintf(disk, "t%dd%d", targ, lun);
258 
259 	disk_common(minor, node, disk, RM_STALE);
260 
261 	return (DEVFSADM_CONTINUE);
262 }
263 
264 static int
265 disk_callback_fabric(di_minor_t minor, di_node_t node)
266 {
267 	char disk[DISK_SUBPATH_MAX];
268 	int lun;
269 	int count;
270 	int *intp;
271 	uchar_t *str;
272 	uchar_t *wwn;
273 	uchar_t ascii_wwn[ASCIIWWNSIZE];
274 
275 	if (di_prop_lookup_strings(DDI_DEV_T_ANY, node,
276 	    "client-guid", (char **)&wwn) > 0) {
277 		if (strlcpy((char *)ascii_wwn, (char *)wwn,
278 		    sizeof (ascii_wwn)) >= sizeof (ascii_wwn)) {
279 			devfsadm_errprint("SUNW_disk_link: GUID too long:%d",
280 			    strlen((char *)wwn));
281 			return (DEVFSADM_CONTINUE);
282 		}
283 		lun = 0;
284 	} else if (di_prop_lookup_bytes(DDI_DEV_T_ANY, node,
285 	    "port-wwn", &wwn) > 0) {
286 		if (di_prop_lookup_ints(DDI_DEV_T_ANY, node,
287 		    SCSI_ADDR_PROP_LUN, &intp) > 0) {
288 			lun = *intp;
289 		} else {
290 			lun = 0;
291 		}
292 
293 		for (count = 0, str = ascii_wwn; count < 8; count++, str += 2) {
294 			(void) sprintf((caddr_t)str, "%02x", wwn[count]);
295 		}
296 		*str = '\0';
297 	} else {
298 		return (DEVFSADM_CONTINUE);
299 	}
300 
301 	for (str = ascii_wwn; *str != '\0'; str++) {
302 		*str = DISK_LINK_TO_UPPER(*str);
303 	}
304 
305 	(void) snprintf(disk, DISK_SUBPATH_MAX, "t%sd%d", ascii_wwn, lun);
306 
307 	disk_common(minor, node, disk, RM_STALE);
308 
309 	return (DEVFSADM_CONTINUE);
310 }
311 
312 static int
313 disk_callback_sas(di_minor_t minor, di_node_t node)
314 {
315 	char disk[DISK_SUBPATH_MAX];
316 	int lun64_found = 0;
317 	scsi_lun64_t lun64, sl;
318 	scsi_lun_t lun;
319 	int64_t *lun64p;
320 	uint64_t wwn;
321 	int *intp;
322 	char *tgt_port;
323 	uchar_t addr_method;
324 
325 	/* Get lun property */
326 	if (di_prop_lookup_int64(DDI_DEV_T_ANY, node,
327 	    SCSI_ADDR_PROP_LUN64, &lun64p) > 0) {
328 		if (*lun64p != SCSI_LUN64_ILLEGAL) {
329 			lun64_found = 1;
330 			lun64 = (uint64_t)*lun64p;
331 		}
332 	}
333 	if ((!lun64_found) && (di_prop_lookup_ints(DDI_DEV_T_ANY, node,
334 	    SCSI_ADDR_PROP_LUN, &intp) > 0)) {
335 		lun64 = (uint64_t)*intp;
336 	}
337 
338 	lun = scsi_lun64_to_lun(lun64);
339 
340 	addr_method = (lun.sl_lun1_msb & SCSI_LUN_AM_MASK);
341 
342 	if (di_prop_lookup_strings(DDI_DEV_T_ANY, node,
343 	    SCSI_ADDR_PROP_TARGET_PORT, &tgt_port) > 0) {
344 		(void) scsi_wwnstr_to_wwn(tgt_port, &wwn);
345 		if ((addr_method == SCSI_LUN_AM_PDEV) &&
346 		    (lun.sl_lun2_msb == 0) && (lun.sl_lun2_lsb == 0) &&
347 		    (lun.sl_lun3_msb == 0) && (lun.sl_lun3_lsb == 0) &&
348 		    (lun.sl_lun4_msb == 0) && (lun.sl_lun4_lsb == 0)) {
349 			(void) snprintf(disk, DISK_SUBPATH_MAX,
350 			    "t%"PRIX64"d%"PRId64, wwn, lun64);
351 		} else if ((addr_method == SCSI_LUN_AM_FLAT) &&
352 		    (lun.sl_lun2_msb == 0) && (lun.sl_lun2_lsb == 0) &&
353 		    (lun.sl_lun3_msb == 0) && (lun.sl_lun3_lsb == 0) &&
354 		    (lun.sl_lun4_msb == 0) && (lun.sl_lun4_lsb == 0)) {
355 			sl = (lun.sl_lun1_msb << 8) | lun.sl_lun1_lsb;
356 			(void) snprintf(disk, DISK_SUBPATH_MAX,
357 			    "t%"PRIX64"d%"PRIX16, wwn, sl);
358 		} else {
359 			(void) snprintf(disk, DISK_SUBPATH_MAX,
360 			    "t%"PRIX64"d%"PRIX64, wwn, lun64);
361 		}
362 	} else if (di_prop_lookup_ints(DDI_DEV_T_ANY, node,
363 	    SCSI_ADDR_PROP_SATA_PHY, &intp) > 0) {
364 		/* Use phy format naming, for SATA devices without wwn */
365 		if ((addr_method == SCSI_LUN_AM_PDEV) &&
366 		    (lun.sl_lun2_msb == 0) && (lun.sl_lun2_lsb == 0) &&
367 		    (lun.sl_lun3_msb == 0) && (lun.sl_lun3_lsb == 0) &&
368 		    (lun.sl_lun4_msb == 0) && (lun.sl_lun4_lsb == 0)) {
369 			(void) snprintf(disk, DISK_SUBPATH_MAX,
370 			    "t%dd%"PRId64, *intp, lun64);
371 		} else if ((addr_method == SCSI_LUN_AM_FLAT) &&
372 		    (lun.sl_lun2_msb == 0) && (lun.sl_lun2_lsb == 0) &&
373 		    (lun.sl_lun3_msb == 0) && (lun.sl_lun3_lsb == 0) &&
374 		    (lun.sl_lun4_msb == 0) && (lun.sl_lun4_lsb == 0)) {
375 			sl = (lun.sl_lun1_msb << 8) | lun.sl_lun1_lsb;
376 			(void) snprintf(disk, DISK_SUBPATH_MAX,
377 			    "t%dd%"PRIX16, *intp, sl);
378 		} else {
379 			(void) snprintf(disk, DISK_SUBPATH_MAX,
380 			    "t%dd%"PRIX64, *intp, lun64);
381 		}
382 	} else {
383 		return (DEVFSADM_CONTINUE);
384 	}
385 
386 	disk_common(minor, node, disk, RM_STALE);
387 
388 	return (DEVFSADM_CONTINUE);
389 }
390 
391 /*
392  * xVM virtual block device
393  *
394  * Xen passes device number in next format:
395  *
396  *    1 << 28 | disk << 8 | partition      xvd, disks or partitions 16 onwards
397  *  202 <<  8 | disk << 4 | partition      xvd, disks and partitions up to 15
398  *    8 <<  8 | disk << 4 | partition      sd, disks and partitions up to 15
399  *    3 <<  8 | disk << 6 | partition      hd, disks 0..1, partitions 0..63
400  *   22 <<  8 | (disk-2) << 6 | partition  hd, disks 2..3, partitions 0..63
401  *    2 << 28 onwards                      reserved for future use
402  *   other values less than 1 << 28        deprecated / reserved
403  *
404  * The corresponding Solaris /dev/dsk name can be:
405  *
406  *          c0tYdXsN
407  *
408  * where Y,X >= 0.
409  *
410  * For PV guests using the legacy naming (0, 1, 2, ...)
411  * the Solaris disk names created will be c0d[0..767]sN
412  */
413 
414 #define	HD_BASE		(3 << 8)
415 #define	XEN_EXT_SHIFT	(28)
416 
417 /*
418  * Return: Number of parsed and written parameters
419  */
420 static int
421 decode_xen_device(uint_t device, uint_t *disk, uint_t *plun)
422 {
423 	uint_t dsk, lun = 0;
424 	int ret = 1;
425 
426 	if ((device >> XEN_EXT_SHIFT) > 1)
427 		return (0);
428 
429 	if (device < HD_BASE) {
430 		/* legacy device address */
431 		dsk = device;
432 		goto end;
433 	}
434 
435 	ret = 2;
436 	if (device & (1 << XEN_EXT_SHIFT)) {
437 		/* extended */
438 		dsk = device & (~0xff);
439 		lun = device & 0xff;
440 		goto end;
441 	}
442 
443 	switch (device >> 8) {
444 	case 202:				/* xvd */
445 		dsk = (device >> 4) & 0xf;
446 		lun =  device & 0xf;
447 		break;
448 	case 8:					/* sd */
449 		dsk = device & (~0xf);
450 		lun = device & 0xf;
451 		break;
452 	case 3:					/* hd, disk 0..1 */
453 		dsk = device & (~0x3f);
454 		lun = device & 0x3f;
455 		break;
456 	case 22:				/* hd, disk 2..3 */
457 		dsk = device & (~0x3f);
458 		lun = device & 0x3f;
459 		break;
460 	default:
461 		return (0);
462 	}
463 end:
464 	*disk = dsk;
465 	*plun = lun;
466 	return (ret);
467 }
468 
469 static int
470 disk_callback_xvmd(di_minor_t minor, di_node_t node)
471 {
472 	char *addr;
473 	char disk[16];
474 	uint_t targ;
475 	uint_t dsk, lun;
476 	int res;
477 
478 	addr = di_bus_addr(node);
479 	targ = strtol(addr, (char **)NULL, 10);
480 
481 	res = decode_xen_device(targ, &dsk, &lun);
482 
483 	/* HVM device names are generated using the standard generator */
484 
485 	if (res == 1)
486 		(void) snprintf(disk, sizeof (disk),  "d%d", dsk);
487 	else if (res == 2)
488 		(void) snprintf(disk, sizeof (disk), "t%dd%d", dsk, lun);
489 	else {
490 		devfsadm_errprint("%s: invalid disk device number (%s)\n",
491 		    modname, addr);
492 		return (DEVFSADM_CONTINUE);
493 	}
494 	disk_common(minor, node, disk, 0);
495 	return (DEVFSADM_CONTINUE);
496 
497 }
498 
499 /*
500  * This function is called for every disk minor node.
501  * Calls enumerate to assign a logical controller number, and
502  * then devfsadm_mklink to make the link.
503  */
504 static void
505 disk_common(di_minor_t minor, di_node_t node, char *disk, int flags)
506 {
507 	char l_path[PATH_MAX + 1];
508 	char sec_path[PATH_MAX + 1];
509 	char stale_re[DISK_SUBPATH_MAX];
510 	char *dir;
511 	char slice[4];
512 	char *mn;
513 	char *ctrl;
514 	char *nt = NULL;
515 	int *int_prop;
516 	int  nflags = 0;
517 #if defined(__i386) || defined(__amd64)
518 	char mn_copy[4];
519 	char *part;
520 	int part_num;
521 #endif
522 
523 	mn = di_minor_name(minor);
524 	if (strstr(mn, ",raw")) {
525 		dir = "rdsk";
526 #if defined(__i386) || defined(__amd64)
527 		(void) strncpy(mn_copy, mn, 4);
528 		part = strtok(mn_copy, ",");
529 #endif
530 	} else {
531 		dir = "dsk";
532 #if defined(__i386) || defined(__amd64)
533 		part = mn;
534 #endif
535 	}
536 
537 #if defined(__i386) || defined(__amd64)
538 	/*
539 	 * The following is a table describing the allocation of
540 	 * minor numbers, minor names and /dev/dsk names for partitions
541 	 * and slices on x86 systems.
542 	 *
543 	 *	Minor Number	Minor Name	/dev/dsk name
544 	 *	---------------------------------------------
545 	 *	0 to 15		"a" to "p"	s0 to s15
546 	 *	16		"q"		p0
547 	 *	17 to 20	"r" to "u"	p1 to p4
548 	 *	21 to 52	"p5" to "p36"	p5 to p36
549 	 *
550 	 */
551 	part_num = atoi(part + 1);
552 
553 	if ((mn[0] == 'p') && (part_num >= 5)) {
554 		/* logical drive */
555 		(void) snprintf(slice, 4, "%s", part);
556 	} else {
557 #endif
558 	if (mn[0] < 'q') {
559 		(void) sprintf(slice, "s%d", mn[0] - 'a');
560 	} else if (strncmp(mn, MN_EFI, 2) != 0) {
561 		(void) sprintf(slice, "p%d", mn[0] - 'q');
562 	} else {
563 		/* For EFI label */
564 		(void) sprintf(slice, SLICE_EFI);
565 	}
566 #if defined(__i386) || defined(__amd64)
567 	}
568 #endif
569 
570 	nflags = 0;
571 	if (system_labeled) {
572 		nt = di_minor_nodetype(minor);
573 		if ((nt != NULL) &&
574 		    ((strcmp(nt, DDI_NT_CD) == 0) ||
575 		    (strcmp(nt, DDI_NT_CD_CHAN) == 0) ||
576 		    (strcmp(nt, DDI_NT_BLOCK_CHAN) == 0))) {
577 			nflags = DA_ADD|DA_CD;
578 		}
579 	}
580 
581 	if (reserved_links_exist(node, minor, nflags) == DEVFSADM_SUCCESS) {
582 		devfsadm_print(disk_mid, "Reserved link exists. Not "
583 		    "creating links for slice %s\n", slice);
584 		return;
585 	}
586 
587 	if (NULL == (ctrl = diskctrl(node, minor)))
588 		return;
589 
590 	(void) strcpy(l_path, dir);
591 	(void) strcat(l_path, "/c");
592 	(void) strcat(l_path, ctrl);
593 	(void) strcat(l_path, disk);
594 
595 	/*
596 	 * If switching between SMI and EFI label or vice versa
597 	 * cleanup the previous label's devlinks.
598 	 */
599 	if (*mn == *(MN_SMI) || (strncmp(mn, MN_EFI, 2) == 0)) {
600 		char *s, tpath[PATH_MAX + 1];
601 		struct stat sb;
602 
603 		s = l_path + strlen(l_path);
604 		(void) strcat(l_path, (*mn == *(MN_SMI))
605 		    ? SLICE_EFI : SLICE_SMI);
606 		/*
607 		 * Attempt the remove only if the stale link exists
608 		 */
609 		(void) snprintf(tpath, sizeof (tpath), "%s/dev/%s",
610 		    devfsadm_root_path(), l_path);
611 		if (lstat(tpath, &sb) != -1)
612 			devfsadm_rm_all(l_path);
613 		*s = '\0';
614 	}
615 	(void) strcat(l_path, slice);
616 
617 	(void) devfsadm_mklink(l_path, node, minor, nflags);
618 
619 	/* secondary links for removable and hotpluggable devices */
620 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "removable-media",
621 	    &int_prop) >= 0) {
622 		(void) strcpy(sec_path, "removable-media/");
623 		(void) strcat(sec_path, l_path);
624 		(void) devfsadm_secondary_link(sec_path, l_path, 0);
625 	}
626 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "hotpluggable",
627 	    &int_prop) >= 0) {
628 		(void) strcpy(sec_path, "hotpluggable/");
629 		(void) strcat(sec_path, l_path);
630 		(void) devfsadm_secondary_link(sec_path, l_path, 0);
631 	}
632 
633 	if ((flags & RM_STALE) == RM_STALE) {
634 		(void) strcpy(stale_re, "^");
635 		(void) strcat(stale_re, dir);
636 		(void) strcat(stale_re, "/c");
637 		(void) strcat(stale_re, ctrl);
638 		(void) strcat(stale_re, "t[0-9A-F]+d[0-9]+(s[0-9]+)?$");
639 		/*
640 		 * optimizations are made inside of devfsadm_rm_stale_links
641 		 * instead of before calling the function, as it always
642 		 * needs to add the valid link to the cache.
643 		 */
644 		devfsadm_rm_stale_links(stale_re, l_path, node, minor);
645 	}
646 
647 	free(ctrl);
648 }
649 
650 
651 /* index of enumeration rule applicable to this module */
652 #define	RULE_INDEX	0
653 
654 static char *
655 diskctrl(di_node_t node, di_minor_t minor)
656 {
657 	char path[PATH_MAX + 1];
658 	char *devfspath;
659 	char *buf, *mn;
660 
661 	devfsadm_enumerate_t rules[3] = {
662 	    {"^r?dsk$/^c([0-9]+)", 1, MATCH_PARENT},
663 	    {"^cfg$/^c([0-9]+)$", 1, MATCH_ADDR},
664 	    {"^scsi$/^.+$/^c([0-9]+)", 1, MATCH_PARENT}
665 	};
666 
667 	mn = di_minor_name(minor);
668 
669 	if ((devfspath = di_devfs_path(node)) == NULL) {
670 		return (NULL);
671 	}
672 	(void) strcpy(path, devfspath);
673 	(void) strcat(path, ":");
674 	(void) strcat(path, mn);
675 	di_devfs_path_free(devfspath);
676 
677 	/*
678 	 * Use controller component of disk path
679 	 */
680 	if (disk_enumerate_int(path, RULE_INDEX, &buf, rules, 3) ==
681 	    DEVFSADM_MULTIPLE) {
682 
683 		/*
684 		 * We failed because there are multiple logical controller
685 		 * numbers for a single physical controller.  If we use node
686 		 * name also in the match it should fix this and only find one
687 		 * logical controller. (See 4045879).
688 		 * NOTE: Rules for controllers are not changed, as there is
689 		 * no unique controller number for them in this case.
690 		 *
691 		 * MATCH_UNCACHED flag is private to the "disks" and "sgen"
692 		 * modules. NOT to be used by other modules.
693 		 */
694 
695 		rules[0].flags = MATCH_NODE | MATCH_UNCACHED; /* disks */
696 		rules[2].flags = MATCH_NODE | MATCH_UNCACHED; /* generic scsi */
697 		if (devfsadm_enumerate_int(path, RULE_INDEX, &buf, rules, 3)) {
698 			return (NULL);
699 		}
700 	}
701 
702 	return (buf);
703 }
704 
705 typedef struct dvlist {
706 	char *dv_link;
707 	struct dvlist *dv_next;
708 } dvlist_t;
709 
710 static void
711 free_dvlist(dvlist_t **pp)
712 {
713 	dvlist_t *entry;
714 
715 	while (*pp) {
716 		entry = *pp;
717 		*pp = entry->dv_next;
718 		assert(entry->dv_link);
719 		free(entry->dv_link);
720 		free(entry);
721 	}
722 }
723 static int
724 dvlink_cb(di_devlink_t devlink, void *arg)
725 {
726 	char *path;
727 	char *can_path;
728 	dvlist_t **pp = (dvlist_t **)arg;
729 	dvlist_t *entry = NULL;
730 
731 	entry = calloc(1, sizeof (dvlist_t));
732 	if (entry == NULL) {
733 		devfsadm_errprint("%s: calloc failed\n", modname);
734 		goto error;
735 	}
736 
737 	path = (char *)di_devlink_path(devlink);
738 	assert(path);
739 	if (path == NULL) {
740 		devfsadm_errprint("%s: di_devlink_path() returned NULL\n",
741 		    modname);
742 		goto error;
743 	}
744 
745 	devfsadm_print(disk_mid, "%s: found link %s in reverse link cache\n",
746 	    modname, path);
747 
748 	/*
749 	 * Return linkname in canonical form i.e. without the
750 	 * "/dev/" prefix
751 	 */
752 	can_path = strstr(path, "/dev/");
753 	if (can_path == NULL) {
754 		devfsadm_errprint("%s: devlink path %s has no /dev/\n",
755 		    modname, path);
756 		goto error;
757 	}
758 
759 	entry->dv_link = s_strdup(can_path + strlen("/dev/"));
760 	entry->dv_next = *pp;
761 	*pp = entry;
762 
763 	return (DI_WALK_CONTINUE);
764 
765 error:
766 	free(entry);
767 	free_dvlist(pp);
768 	*pp = NULL;
769 	return (DI_WALK_TERMINATE);
770 }
771 
772 /*
773  * Returns success only if all goes well. If there is no matching reserved link
774  * or if there is an error, we assume no match. It is better to err on the side
775  * of caution by creating extra links than to miss out creating a required link.
776  */
777 static int
778 reserved_links_exist(di_node_t node, di_minor_t minor, int nflags)
779 {
780 	di_devlink_handle_t dvlink_cache = devfsadm_devlink_cache();
781 	char phys_path[PATH_MAX];
782 	char *minor_path;
783 	dvlist_t *head;
784 	dvlist_t *entry;
785 	char *s;
786 	char l[PATH_MAX];
787 	int switch_link = 0;
788 	char *mn = di_minor_name(minor);
789 
790 	if (dvlink_cache == NULL || mn == NULL) {
791 		devfsadm_errprint("%s: No minor or devlink cache\n", modname);
792 		return (DEVFSADM_FAILURE);
793 	}
794 
795 	if (!devfsadm_have_reserved()) {
796 		devfsadm_print(disk_mid, "%s: No reserved links\n", modname);
797 		return (DEVFSADM_FAILURE);
798 	}
799 
800 	minor_path = di_devfs_minor_path(minor);
801 	if (minor_path == NULL) {
802 		devfsadm_errprint("%s: di_devfs_minor_path failed\n", modname);
803 		return (DEVFSADM_FAILURE);
804 	}
805 
806 	(void) strlcpy(phys_path, minor_path, sizeof (phys_path));
807 
808 	di_devfs_path_free(minor_path);
809 
810 	head = NULL;
811 	(void) di_devlink_cache_walk(dvlink_cache, DISK_LINK_RE, phys_path,
812 	    DI_PRIMARY_LINK, &head, dvlink_cb);
813 
814 	/*
815 	 * We may be switching between EFI label and SMI label in which case
816 	 * we only have minors of the other type.
817 	 */
818 	if (head == NULL && (*mn == *(MN_SMI) ||
819 	    (strncmp(mn, MN_EFI, 2) == 0))) {
820 		devfsadm_print(disk_mid, "%s: No links for minor %s in /dev. "
821 		    "Trying another label\n", modname, mn);
822 		s = strrchr(phys_path, ':');
823 		if (s == NULL) {
824 			devfsadm_errprint("%s: invalid minor path: %s\n",
825 			    modname, phys_path);
826 			return (DEVFSADM_FAILURE);
827 		}
828 		(void) snprintf(s+1, sizeof (phys_path) - (s + 1 - phys_path),
829 		    "%s%s", *mn == *(MN_SMI) ? MN_EFI : MN_SMI,
830 		    strstr(s, ",raw") ? ",raw" : "");
831 		(void) di_devlink_cache_walk(dvlink_cache, DISK_LINK_RE,
832 		    phys_path, DI_PRIMARY_LINK, &head, dvlink_cb);
833 	}
834 
835 	if (head == NULL) {
836 		devfsadm_print(disk_mid, "%s: minor %s has no links in /dev\n",
837 		    modname, phys_path);
838 		/* no links on disk */
839 		return (DEVFSADM_FAILURE);
840 	}
841 
842 	/*
843 	 * It suffices to use 1 link to this minor, since
844 	 * we are matching with reserved IDs on the basis of
845 	 * the controller number which will be the same for
846 	 * all links to this minor.
847 	 */
848 	if (!devfsadm_is_reserved(disks_re_array, head->dv_link)) {
849 		/* not reserved links */
850 		devfsadm_print(disk_mid, "%s: devlink %s and its minor "
851 		    "are NOT reserved\n", modname, head->dv_link);
852 		free_dvlist(&head);
853 		return (DEVFSADM_FAILURE);
854 	}
855 
856 	devfsadm_print(disk_mid, "%s: devlink %s and its minor are on "
857 	    "reserved list\n", modname, head->dv_link);
858 
859 	/*
860 	 * Switch between SMI and EFI labels if required
861 	 */
862 	switch_link = 0;
863 	if (*mn == *(MN_SMI) || (strncmp(mn, MN_EFI, 2) == 0)) {
864 		for (entry = head; entry; entry = entry->dv_next) {
865 			s = strrchr(entry->dv_link, '/');
866 			assert(s);
867 			if (s == NULL) {
868 				devfsadm_errprint("%s: disk link %s has no "
869 				    "directory\n", modname, entry->dv_link);
870 				continue;
871 			}
872 			if (*mn == *(MN_SMI) && strchr(s, 's') == NULL) {
873 				(void) snprintf(l, sizeof (l), "%s%s",
874 				    entry->dv_link, SLICE_SMI);
875 				switch_link = 1;
876 				devfsadm_print(disk_mid, "%s: switching "
877 				    "reserved link from EFI to SMI label. "
878 				    "New link is %s\n", modname, l);
879 			} else if (strncmp(mn, MN_EFI, 2) == 0 &&
880 			    (s = strchr(s, 's'))) {
881 				*s = '\0';
882 				(void) snprintf(l, sizeof (l), "%s",
883 				    entry->dv_link);
884 				*s = 's';
885 				switch_link = 1;
886 				devfsadm_print(disk_mid, "%s: switching "
887 				    "reserved link from SMI to EFI label. "
888 				    "New link is %s\n", modname, l);
889 			}
890 			if (switch_link) {
891 				devfsadm_print(disk_mid, "%s: switching "
892 				    "link: deleting %s and creating %s\n",
893 				    modname, entry->dv_link, l);
894 				devfsadm_rm_link(entry->dv_link);
895 				(void) devfsadm_mklink(l, node, minor, nflags);
896 			}
897 		}
898 	}
899 	free_dvlist(&head);
900 
901 	/*
902 	 * return SUCCESS to indicate that new links to this minor should not
903 	 * be created so that only compatibility links to this minor remain.
904 	 */
905 	return (DEVFSADM_SUCCESS);
906 }
907