xref: /illumos-gate/usr/src/cmd/devfsadm/disk_link.c (revision e37c6c376a1a22a828db3bb5ab40c86cb08f9c86)
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 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <devfsadm.h>
29 #include <stdio.h>
30 #include <strings.h>
31 #include <stdlib.h>
32 #include <limits.h>
33 #include <sys/stat.h>
34 #include <bsm/devalloc.h>
35 
36 #define	DISK_SUBPATH_MAX 100
37 #define	RM_STALE 0x01
38 #define	DISK_LINK_RE	"^r?dsk/c[0-9]+(t[0-9A-F]+)?d[0-9]+(((s|p))[0-9]+)?$"
39 #define	DISK_LINK_TO_UPPER(ch)\
40 	(((ch) >= 'a' && (ch) <= 'z') ? (ch - 'a' + 'A') : ch)
41 
42 #define	SLICE_SMI	"s7"
43 #define	SLICE_EFI	""
44 
45 #define	MN_SMI		"h"
46 #define	MN_EFI		"wd"
47 #define	ASCIIWWNSIZE	255
48 
49 extern int system_labeled;
50 
51 static int disk_callback_chan(di_minor_t minor, di_node_t node);
52 static int disk_callback_nchan(di_minor_t minor, di_node_t node);
53 static int disk_callback_wwn(di_minor_t minor, di_node_t node);
54 static int disk_callback_fabric(di_minor_t minor, di_node_t node);
55 static void disk_common(di_minor_t minor, di_node_t node, char *disk,
56 				int flags);
57 static char *diskctrl(di_node_t node, di_minor_t minor);
58 static int reserved_links_exist(di_node_t node, di_minor_t minor, int nflags);
59 
60 
61 static devfsadm_create_t disk_cbt[] = {
62 	{ "disk", "ddi_block", NULL,
63 	    TYPE_EXACT, ILEVEL_0, disk_callback_nchan
64 	},
65 	{ "disk", "ddi_block:channel", NULL,
66 	    TYPE_EXACT, ILEVEL_0, disk_callback_chan
67 	},
68 	{ "disk", "ddi_block:fabric", NULL,
69 		TYPE_EXACT, ILEVEL_0, disk_callback_fabric
70 	},
71 	{ "disk", "ddi_block:wwn", NULL,
72 	    TYPE_EXACT, ILEVEL_0, disk_callback_wwn
73 	},
74 	{ "disk", "ddi_block:cdrom", NULL,
75 	    TYPE_EXACT, ILEVEL_0, disk_callback_nchan
76 	},
77 	{ "disk", "ddi_block:cdrom:channel", NULL,
78 	    TYPE_EXACT, ILEVEL_0, disk_callback_chan
79 	},
80 };
81 
82 DEVFSADM_CREATE_INIT_V0(disk_cbt);
83 
84 /*
85  * HOT auto cleanup of disks not desired.
86  */
87 static devfsadm_remove_t disk_remove_cbt[] = {
88 	{ "disk", DISK_LINK_RE, RM_POST,
89 		ILEVEL_0, devfsadm_rm_all
90 	}
91 };
92 
93 DEVFSADM_REMOVE_INIT_V0(disk_remove_cbt);
94 
95 static devlink_re_t disks_re_array[] = {
96 	{"^r?dsk/c([0-9]+)", 1},
97 	{"^cfg/c([0-9]+)$", 1},
98 	{"^scsi/.+/c([0-9]+)", 1},
99 	{NULL}
100 };
101 
102 static char *disk_mid = "disk_mid";
103 static char *modname = "disk_link";
104 
105 int
106 minor_init()
107 {
108 	devfsadm_print(disk_mid,
109 	    "%s: minor_init(): Creating disks reserved ID cache\n",
110 	    modname);
111 	return (devfsadm_reserve_id_cache(disks_re_array, NULL));
112 }
113 
114 static int
115 disk_callback_chan(di_minor_t minor, di_node_t node)
116 {
117 	char *addr;
118 	char disk[20];
119 	uint_t targ;
120 	uint_t lun;
121 
122 	addr = di_bus_addr(node);
123 	(void) sscanf(addr, "%X,%X", &targ, &lun);
124 	(void) sprintf(disk, "t%dd%d", targ, lun);
125 	disk_common(minor, node, disk, 0);
126 	return (DEVFSADM_CONTINUE);
127 
128 }
129 
130 static int
131 disk_callback_nchan(di_minor_t minor, di_node_t node)
132 {
133 	char *addr;
134 	char disk[10];
135 	uint_t lun;
136 
137 	addr = di_bus_addr(node);
138 	(void) sscanf(addr, "%X", &lun);
139 	(void) sprintf(disk, "d%d", lun);
140 	disk_common(minor, node, disk, 0);
141 	return (DEVFSADM_CONTINUE);
142 
143 }
144 
145 static int
146 disk_callback_wwn(di_minor_t minor, di_node_t node)
147 {
148 	char disk[10];
149 	int lun;
150 	int targ;
151 	int *intp;
152 
153 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "target", &intp) <= 0) {
154 		return (DEVFSADM_CONTINUE);
155 	}
156 	targ = *intp;
157 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "lun", &intp) <= 0) {
158 		lun = 0;
159 	} else {
160 		lun = *intp;
161 	}
162 	(void) sprintf(disk, "t%dd%d", targ, lun);
163 
164 	disk_common(minor, node, disk, RM_STALE);
165 
166 	return (DEVFSADM_CONTINUE);
167 }
168 
169 static int
170 disk_callback_fabric(di_minor_t minor, di_node_t node)
171 {
172 	char disk[DISK_SUBPATH_MAX];
173 	int lun;
174 	int count;
175 	int *intp;
176 	uchar_t *str;
177 	uchar_t *wwn;
178 	uchar_t ascii_wwn[ASCIIWWNSIZE];
179 
180 	if (di_prop_lookup_strings(DDI_DEV_T_ANY, node,
181 	    "client-guid", (char **)&wwn) > 0) {
182 		if (strlcpy((char *)ascii_wwn, (char *)wwn,
183 		    sizeof (ascii_wwn)) >= sizeof (ascii_wwn)) {
184 			devfsadm_errprint("SUNW_disk_link: GUID too long:%d",
185 			    strlen((char *)wwn));
186 			return (DEVFSADM_CONTINUE);
187 		}
188 		lun = 0;
189 	} else if (di_prop_lookup_bytes(DDI_DEV_T_ANY, node,
190 	    "port-wwn", &wwn) > 0) {
191 		if (di_prop_lookup_ints(DDI_DEV_T_ANY, node,
192 		    "lun", &intp) > 0) {
193 			lun = *intp;
194 		} else {
195 			lun = 0;
196 		}
197 
198 		for (count = 0, str = ascii_wwn; count < 8; count++, str += 2) {
199 			(void) sprintf((caddr_t)str, "%02x", wwn[count]);
200 		}
201 		*str = '\0';
202 	} else {
203 		return (DEVFSADM_CONTINUE);
204 	}
205 
206 	for (str = ascii_wwn; *str != '\0'; str++) {
207 		*str = DISK_LINK_TO_UPPER(*str);
208 	}
209 
210 	(void) snprintf(disk, DISK_SUBPATH_MAX, "t%sd%d", ascii_wwn, lun);
211 
212 	disk_common(minor, node, disk, RM_STALE);
213 
214 	return (DEVFSADM_CONTINUE);
215 }
216 
217 /*
218  * This function is called for every disk minor node.
219  * Calls enumerate to assign a logical controller number, and
220  * then devfsadm_mklink to make the link.
221  */
222 static void
223 disk_common(di_minor_t minor, di_node_t node, char *disk, int flags)
224 {
225 	char l_path[PATH_MAX + 1];
226 	char sec_path[PATH_MAX + 1];
227 	char stale_re[DISK_SUBPATH_MAX];
228 	char *dir;
229 	char slice[4];
230 	char *mn;
231 	char *ctrl;
232 	char *nt = NULL;
233 	int *int_prop;
234 	int  nflags = 0;
235 
236 	if (strstr(mn = di_minor_name(minor), ",raw")) {
237 		dir = "rdsk";
238 	} else {
239 		dir = "dsk";
240 	}
241 
242 	if (mn[0] < 113) {
243 		(void) sprintf(slice, "s%d", mn[0] - 'a');
244 	} else if (strncmp(mn, MN_EFI, 2) != 0) {
245 		(void) sprintf(slice, "p%d", mn[0] - 'q');
246 	} else {
247 		/* For EFI label */
248 		(void) sprintf(slice, SLICE_EFI);
249 	}
250 
251 	nflags = 0;
252 	if (system_labeled) {
253 		nt = di_minor_nodetype(minor);
254 		if ((nt != NULL) &&
255 		    ((strcmp(nt, DDI_NT_CD) == 0) ||
256 		    (strcmp(nt, DDI_NT_CD_CHAN) == 0) ||
257 		    (strcmp(nt, DDI_NT_BLOCK_CHAN) == 0))) {
258 			nflags = DA_ADD|DA_CD;
259 		}
260 	}
261 
262 	if (reserved_links_exist(node, minor, nflags) == DEVFSADM_SUCCESS) {
263 		devfsadm_print(disk_mid, "Reserved link exists. Not "
264 		    "creating links for slice %s\n", slice);
265 		return;
266 	}
267 
268 	if (NULL == (ctrl = diskctrl(node, minor)))
269 		return;
270 
271 	(void) strcpy(l_path, dir);
272 	(void) strcat(l_path, "/c");
273 	(void) strcat(l_path, ctrl);
274 	(void) strcat(l_path, disk);
275 
276 	/*
277 	 * If switching between SMI and EFI label or vice versa
278 	 * cleanup the previous label's devlinks.
279 	 */
280 	if (*mn == *(MN_SMI) || (strncmp(mn, MN_EFI, 2) == 0)) {
281 		char *s, tpath[PATH_MAX + 1];
282 		struct stat sb;
283 
284 		s = l_path + strlen(l_path);
285 		(void) strcat(l_path, (*mn == *(MN_SMI))
286 		    ? SLICE_EFI : SLICE_SMI);
287 		/*
288 		 * Attempt the remove only if the stale link exists
289 		 */
290 		(void) snprintf(tpath, sizeof (tpath), "%s/dev/%s",
291 		    devfsadm_root_path(), l_path);
292 		if (lstat(tpath, &sb) != -1)
293 			devfsadm_rm_all(l_path);
294 		*s = '\0';
295 	}
296 	(void) strcat(l_path, slice);
297 
298 	(void) devfsadm_mklink(l_path, node, minor, nflags);
299 
300 	/* secondary links for removable and hotpluggable devices */
301 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "removable-media",
302 	    &int_prop) >= 0) {
303 		(void) strcpy(sec_path, "removable-media/");
304 		(void) strcat(sec_path, l_path);
305 		(void) devfsadm_secondary_link(sec_path, l_path, 0);
306 	}
307 	if (di_prop_lookup_ints(DDI_DEV_T_ANY, node, "hotpluggable",
308 	    &int_prop) >= 0) {
309 		(void) strcpy(sec_path, "hotpluggable/");
310 		(void) strcat(sec_path, l_path);
311 		(void) devfsadm_secondary_link(sec_path, l_path, 0);
312 	}
313 
314 	if ((flags & RM_STALE) == RM_STALE) {
315 		(void) strcpy(stale_re, "^");
316 		(void) strcat(stale_re, dir);
317 		(void) strcat(stale_re, "/c");
318 		(void) strcat(stale_re, ctrl);
319 		(void) strcat(stale_re, "t[0-9A-F]+d[0-9]+(s[0-9]+)?$");
320 		/*
321 		 * optimizations are made inside of devfsadm_rm_stale_links
322 		 * instead of before calling the function, as it always
323 		 * needs to add the valid link to the cache.
324 		 */
325 		devfsadm_rm_stale_links(stale_re, l_path, node, minor);
326 	}
327 
328 	free(ctrl);
329 }
330 
331 
332 /* index of enumeration rule applicable to this module */
333 #define	RULE_INDEX	0
334 
335 static char *
336 diskctrl(di_node_t node, di_minor_t minor)
337 {
338 	char path[PATH_MAX + 1];
339 	char *devfspath;
340 	char *buf, *mn;
341 
342 	devfsadm_enumerate_t rules[3] = {
343 	    {"^r?dsk$/^c([0-9]+)", 1, MATCH_PARENT},
344 	    {"^cfg$/^c([0-9]+)$", 1, MATCH_ADDR},
345 	    {"^scsi$/^.+$/^c([0-9]+)", 1, MATCH_PARENT}
346 	};
347 
348 	mn = di_minor_name(minor);
349 
350 	if ((devfspath = di_devfs_path(node)) == NULL) {
351 		return (NULL);
352 	}
353 	(void) strcpy(path, devfspath);
354 	(void) strcat(path, ":");
355 	(void) strcat(path, mn);
356 	di_devfs_path_free(devfspath);
357 
358 	/*
359 	 * Use controller component of disk path
360 	 */
361 	if (disk_enumerate_int(path, RULE_INDEX, &buf, rules, 3) ==
362 	    DEVFSADM_MULTIPLE) {
363 
364 		/*
365 		 * We failed because there are multiple logical controller
366 		 * numbers for a single physical controller.  If we use node
367 		 * name also in the match it should fix this and only find one
368 		 * logical controller. (See 4045879).
369 		 * NOTE: Rules for controllers are not changed, as there is
370 		 * no unique controller number for them in this case.
371 		 *
372 		 * MATCH_UNCACHED flag is private to the "disks" and "sgen"
373 		 * modules. NOT to be used by other modules.
374 		 */
375 
376 		rules[0].flags = MATCH_NODE | MATCH_UNCACHED; /* disks */
377 		rules[2].flags = MATCH_NODE | MATCH_UNCACHED; /* generic scsi */
378 		if (devfsadm_enumerate_int(path, RULE_INDEX, &buf, rules, 3)) {
379 			return (NULL);
380 		}
381 	}
382 
383 	return (buf);
384 }
385 
386 typedef struct dvlist {
387 	char *dv_link;
388 	struct dvlist *dv_next;
389 } dvlist_t;
390 
391 static void
392 free_dvlist(dvlist_t **pp)
393 {
394 	dvlist_t *entry;
395 
396 	while (*pp) {
397 		entry = *pp;
398 		*pp = entry->dv_next;
399 		assert(entry->dv_link);
400 		free(entry->dv_link);
401 		free(entry);
402 	}
403 }
404 static int
405 dvlink_cb(di_devlink_t devlink, void *arg)
406 {
407 	char *path;
408 	char *can_path;
409 	dvlist_t **pp = (dvlist_t **)arg;
410 	dvlist_t *entry = NULL;
411 
412 	entry = calloc(1, sizeof (dvlist_t));
413 	if (entry == NULL) {
414 		devfsadm_errprint("%s: calloc failed\n", modname);
415 		goto error;
416 	}
417 
418 	path = (char *)di_devlink_path(devlink);
419 	assert(path);
420 	if (path == NULL) {
421 		devfsadm_errprint("%s: di_devlink_path() returned NULL\n",
422 		    modname);
423 		goto error;
424 	}
425 
426 	devfsadm_print(disk_mid, "%s: found link %s in reverse link cache\n",
427 	    modname, path);
428 
429 	/*
430 	 * Return linkname in canonical form i.e. without the
431 	 * "/dev/" prefix
432 	 */
433 	can_path = strstr(path, "/dev/");
434 	if (can_path == NULL) {
435 		devfsadm_errprint("%s: devlink path %s has no /dev/\n",
436 		    modname, path);
437 		goto error;
438 	}
439 
440 	entry->dv_link = s_strdup(can_path + strlen("/dev/"));
441 	entry->dv_next = *pp;
442 	*pp = entry;
443 
444 	return (DI_WALK_CONTINUE);
445 
446 error:
447 	free(entry);
448 	free_dvlist(pp);
449 	*pp = NULL;
450 	return (DI_WALK_TERMINATE);
451 }
452 
453 /*
454  * Returns success only if all goes well. If there is no matching reserved link
455  * or if there is an error, we assume no match. It is better to err on the side
456  * of caution by creating extra links than to miss out creating a required link.
457  */
458 static int
459 reserved_links_exist(di_node_t node, di_minor_t minor, int nflags)
460 {
461 	di_devlink_handle_t dvlink_cache = devfsadm_devlink_cache();
462 	char phys_path[PATH_MAX];
463 	char *minor_path;
464 	dvlist_t *head;
465 	dvlist_t *entry;
466 	char *s;
467 	char l[PATH_MAX];
468 	int switch_link = 0;
469 	char *mn = di_minor_name(minor);
470 
471 	if (dvlink_cache == NULL || mn == NULL) {
472 		devfsadm_errprint("%s: No minor or devlink cache\n", modname);
473 		return (DEVFSADM_FAILURE);
474 	}
475 
476 	if (!devfsadm_have_reserved()) {
477 		devfsadm_print(disk_mid, "%s: No reserved links\n", modname);
478 		return (DEVFSADM_FAILURE);
479 	}
480 
481 	minor_path = di_devfs_minor_path(minor);
482 	if (minor_path == NULL) {
483 		devfsadm_errprint("%s: di_devfs_minor_path failed\n", modname);
484 		return (DEVFSADM_FAILURE);
485 	}
486 
487 	(void) strlcpy(phys_path, minor_path, sizeof (phys_path));
488 
489 	di_devfs_path_free(minor_path);
490 
491 	head = NULL;
492 	(void) di_devlink_cache_walk(dvlink_cache, DISK_LINK_RE, phys_path,
493 	    DI_PRIMARY_LINK, &head, dvlink_cb);
494 
495 	/*
496 	 * We may be switching between EFI label and SMI label in which case
497 	 * we only have minors of the other type.
498 	 */
499 	if (head == NULL && (*mn == *(MN_SMI) ||
500 	    (strncmp(mn, MN_EFI, 2) == 0))) {
501 		devfsadm_print(disk_mid, "%s: No links for minor %s in /dev. "
502 		    "Trying another label\n", modname, mn);
503 		s = strrchr(phys_path, ':');
504 		if (s == NULL) {
505 			devfsadm_errprint("%s: invalid minor path: %s\n",
506 			    modname, phys_path);
507 			return (DEVFSADM_FAILURE);
508 		}
509 		(void) snprintf(s+1, sizeof (phys_path) - (s + 1 - phys_path),
510 		    "%s%s", *mn == *(MN_SMI) ? MN_EFI : MN_SMI,
511 		    strstr(s, ",raw") ? ",raw" : "");
512 		(void) di_devlink_cache_walk(dvlink_cache, DISK_LINK_RE,
513 		    phys_path, DI_PRIMARY_LINK, &head, dvlink_cb);
514 	}
515 
516 	if (head == NULL) {
517 		devfsadm_print(disk_mid, "%s: minor %s has no links in /dev\n",
518 		    modname, phys_path);
519 		/* no links on disk */
520 		return (DEVFSADM_FAILURE);
521 	}
522 
523 	/*
524 	 * It suffices to use 1 link to this minor, since
525 	 * we are matching with reserved IDs on the basis of
526 	 * the controller number which will be the same for
527 	 * all links to this minor.
528 	 */
529 	if (!devfsadm_is_reserved(disks_re_array, head->dv_link)) {
530 		/* not reserved links */
531 		devfsadm_print(disk_mid, "%s: devlink %s and its minor "
532 		    "are NOT reserved\n", modname, head->dv_link);
533 		free_dvlist(&head);
534 		return (DEVFSADM_FAILURE);
535 	}
536 
537 	devfsadm_print(disk_mid, "%s: devlink %s and its minor are on "
538 	    "reserved list\n", modname, head->dv_link);
539 
540 	/*
541 	 * Switch between SMI and EFI labels if required
542 	 */
543 	switch_link = 0;
544 	if (*mn == *(MN_SMI) || (strncmp(mn, MN_EFI, 2) == 0)) {
545 		for (entry = head; entry; entry = entry->dv_next) {
546 			s = strrchr(entry->dv_link, '/');
547 			assert(s);
548 			if (s == NULL) {
549 				devfsadm_errprint("%s: disk link %s has no "
550 				    "directory\n", modname, entry->dv_link);
551 				continue;
552 			}
553 			if (*mn == *(MN_SMI) && strchr(s, 's') == NULL) {
554 				(void) snprintf(l, sizeof (l), "%s%s",
555 				    entry->dv_link, SLICE_SMI);
556 				switch_link = 1;
557 				devfsadm_print(disk_mid, "%s: switching "
558 				    "reserved link from EFI to SMI label. "
559 				    "New link is %s\n", modname, l);
560 			} else if (strncmp(mn, MN_EFI, 2) == 0 &&
561 			    (s = strchr(s, 's'))) {
562 				*s = '\0';
563 				(void) snprintf(l, sizeof (l), "%s",
564 				    entry->dv_link);
565 				*s = 's';
566 				switch_link = 1;
567 				devfsadm_print(disk_mid, "%s: switching "
568 				    "reserved link from SMI to EFI label. "
569 				    "New link is %s\n", modname, l);
570 			}
571 			if (switch_link) {
572 				devfsadm_print(disk_mid, "%s: switching "
573 				    "link: deleting %s and creating %s\n",
574 				    modname, entry->dv_link, l);
575 				devfsadm_rm_link(entry->dv_link);
576 				(void) devfsadm_mklink(l, node, minor, nflags);
577 			}
578 		}
579 	}
580 	free_dvlist(&head);
581 
582 	/*
583 	 * return SUCCESS to indicate that new links to this minor should not
584 	 * be created so that only compatibility links to this minor remain.
585 	 */
586 	return (DEVFSADM_SUCCESS);
587 }
588