xref: /illumos-gate/usr/src/uts/common/os/modsubr.c (revision 6f25ad7f)
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 (c) 1990, 2010, Oracle and/or its affiliates. All rights reserved.
23  */
24 
25 #include <sys/param.h>
26 #include <sys/modctl.h>
27 #include <sys/modhash.h>
28 #include <sys/open.h>
29 #include <sys/conf.h>
30 #include <sys/errno.h>
31 #include <sys/sysmacros.h>
32 #include <sys/kmem.h>
33 #include <sys/cmn_err.h>
34 #include <sys/stat.h>
35 #include <sys/mode.h>
36 #include <sys/pathname.h>
37 #include <sys/vnode.h>
38 #include <sys/ddi_impldefs.h>
39 #include <sys/ddi_implfuncs.h>
40 #include <sys/esunddi.h>
41 #include <sys/sunddi.h>
42 #include <sys/sunndi.h>
43 #include <sys/systeminfo.h>
44 #include <sys/hwconf.h>
45 #include <sys/file.h>
46 #include <sys/varargs.h>
47 #include <sys/thread.h>
48 #include <sys/cred.h>
49 #include <sys/autoconf.h>
50 #include <sys/kobj.h>
51 #include <sys/consdev.h>
52 #include <sys/systm.h>
53 #include <sys/debug.h>
54 #include <sys/atomic.h>
55 
56 extern struct dev_ops nodev_ops;
57 extern struct dev_ops mod_nodev_ops;
58 
59 struct mod_noload {
60 	struct mod_noload *mn_next;
61 	char *mn_name;
62 };
63 
64 /*
65  * Function prototypes
66  */
67 static int init_stubs(struct modctl *, struct mod_modinfo *);
68 static int nm_hash(char *);
69 static void make_syscallname(char *, int);
70 static void hwc_hash_init();
71 static void hwc_hash(struct hwc_spec *, major_t);
72 static void hwc_unhash(struct hwc_spec *);
73 
74 int
major_valid(major_t major)75 major_valid(major_t major)
76 {
77 	return (major != DDI_MAJOR_T_NONE &&
78 	    (major >= 0 && major < devcnt));
79 }
80 
81 int
driver_installed(major_t major)82 driver_installed(major_t major)
83 {
84 	return (major_valid(major) && devnamesp[major].dn_name != NULL);
85 }
86 
87 int
driver_active(major_t major)88 driver_active(major_t major)
89 {
90 	return (driver_installed(major) && !(devnamesp[major].dn_flags &
91 	    (DN_DRIVER_REMOVED|DN_DRIVER_INACTIVE)));
92 }
93 
94 struct dev_ops *
mod_hold_dev_by_major(major_t major)95 mod_hold_dev_by_major(major_t major)
96 {
97 	struct dev_ops **devopspp, *ops;
98 	int loaded;
99 	char *drvname;
100 
101 	if (!driver_active(major))
102 		return (NULL);
103 
104 	LOCK_DEV_OPS(&(devnamesp[major].dn_lock));
105 	devopspp = &devopsp[major];
106 	loaded = 1;
107 	while (loaded && !CB_DRV_INSTALLED(*devopspp)) {
108 		UNLOCK_DEV_OPS(&(devnamesp[major].dn_lock));
109 		drvname = mod_major_to_name(major);
110 		if (drvname == NULL)
111 			return (NULL);
112 		loaded = (modload("drv", drvname) != -1);
113 		LOCK_DEV_OPS(&(devnamesp[major].dn_lock));
114 	}
115 	if (loaded) {
116 		INCR_DEV_OPS_REF(*devopspp);
117 		ops = *devopspp;
118 	} else {
119 		ops = NULL;
120 	}
121 	UNLOCK_DEV_OPS(&(devnamesp[major].dn_lock));
122 	return (ops);
123 }
124 
125 #ifdef	DEBUG_RELE
126 static int mod_rele_pause = DEBUG_RELE;
127 #endif	/* DEBUG_RELE */
128 
129 void
mod_rele_dev_by_major(major_t major)130 mod_rele_dev_by_major(major_t major)
131 {
132 	struct dev_ops *ops;
133 	struct devnames *dnp;
134 
135 	if (!driver_active(major))
136 		return;
137 
138 	dnp = &devnamesp[major];
139 	LOCK_DEV_OPS(&dnp->dn_lock);
140 	ops = devopsp[major];
141 	ASSERT(CB_DRV_INSTALLED(ops));
142 
143 #ifdef	DEBUG_RELE
144 	if (!DEV_OPS_HELD(ops))  {
145 		char *s;
146 		static char *msg = "mod_rele_dev_by_major: unheld driver!";
147 
148 		printf("mod_rele_dev_by_major: Major dev <%u>, name <%s>\n",
149 		    (uint_t)major,
150 		    (s = mod_major_to_name(major)) ? s : "unknown");
151 		if (mod_rele_pause)
152 			debug_enter(msg);
153 		else
154 			printf("%s\n", msg);
155 		UNLOCK_DEV_OPS(&dnp->dn_lock);
156 		return;			/* XXX: Note changed behavior */
157 	}
158 
159 #endif	/* DEBUG_RELE */
160 
161 	if (!DEV_OPS_HELD(ops)) {
162 		cmn_err(CE_PANIC,
163 		    "mod_rele_dev_by_major: Unheld driver: major number <%u>",
164 		    (uint_t)major);
165 	}
166 	DECR_DEV_OPS_REF(ops);
167 	UNLOCK_DEV_OPS(&dnp->dn_lock);
168 }
169 
170 struct dev_ops *
mod_hold_dev_by_devi(dev_info_t * devi)171 mod_hold_dev_by_devi(dev_info_t *devi)
172 {
173 	major_t major;
174 	char *name;
175 
176 	name = ddi_get_name(devi);
177 	if ((major = mod_name_to_major(name)) == DDI_MAJOR_T_NONE)
178 		return (NULL);
179 	return (mod_hold_dev_by_major(major));
180 }
181 
182 void
mod_rele_dev_by_devi(dev_info_t * devi)183 mod_rele_dev_by_devi(dev_info_t *devi)
184 {
185 	major_t major;
186 	char *name;
187 
188 	name = ddi_get_name(devi);
189 	if ((major = mod_name_to_major(name)) == DDI_MAJOR_T_NONE)
190 		return;
191 	mod_rele_dev_by_major(major);
192 }
193 
194 int
nomod_zero()195 nomod_zero()
196 {
197 	return (0);
198 }
199 
200 int
nomod_minus_one()201 nomod_minus_one()
202 {
203 	return (-1);
204 }
205 
206 int
nomod_einval()207 nomod_einval()
208 {
209 	return (EINVAL);
210 }
211 
212 void
nomod_void()213 nomod_void()
214 {
215 	/* nothing */
216 }
217 
218 /*
219  * Install all the stubs for a module.
220  * Return zero if there were no errors or an errno value.
221  */
222 int
install_stubs_by_name(struct modctl * modp,char * name)223 install_stubs_by_name(struct modctl *modp, char *name)
224 {
225 	char *p;
226 	char *filenamep;
227 	char namebuf[MODMAXNAMELEN + 12];
228 	struct mod_modinfo *mp;
229 
230 	p = name;
231 	filenamep = name;
232 
233 	while (*p)
234 		if (*p++ == '/')
235 			filenamep = p;
236 
237 	/*
238 	 * Concatenate "name" with "_modname" then look up this symbol
239 	 * in the kernel.  If not found, we're done.
240 	 * If found, then find the "mod" info structure and call init_stubs().
241 	 */
242 	p = namebuf;
243 
244 	while (*filenamep && *filenamep != '.')
245 		*p++ = *filenamep++;
246 
247 	(void) strcpy(p, "_modinfo");
248 
249 	if ((mp = (struct mod_modinfo *)modgetsymvalue(namebuf, 1)) != 0)
250 		return (init_stubs(modp, mp));
251 	else
252 		return (0);
253 }
254 
255 static int
init_stubs(struct modctl * modp,struct mod_modinfo * mp)256 init_stubs(struct modctl *modp, struct mod_modinfo *mp)
257 {
258 	struct mod_stub_info *sp;
259 	int i;
260 	ulong_t offset;
261 	uintptr_t funcadr;
262 	char *funcname;
263 
264 	modp->mod_modinfo = mp;
265 
266 	/*
267 	 * Fill in all stubs for this module.  We can't be lazy, since
268 	 * some calls could come in from interrupt level, and we
269 	 * can't modlookup then (symbols may be paged out).
270 	 */
271 	sp = mp->modm_stubs;
272 	for (i = 0; sp->mods_func_adr; i++, sp++) {
273 		funcname = modgetsymname(sp->mods_stub_adr, &offset);
274 		if (funcname == NULL) {
275 			printf("init_stubs: couldn't find symbol "
276 			    "in module %s\n", mp->modm_module_name);
277 			return (EFAULT);
278 		}
279 		funcadr = kobj_lookup(modp->mod_mp, funcname);
280 
281 		if (kobj_addrcheck(modp->mod_mp, (caddr_t)funcadr)) {
282 			printf("%s:%s() not defined properly\n",
283 			    mp->modm_module_name, funcname);
284 			return (EFAULT);
285 		}
286 		sp->mods_func_adr = funcadr;
287 	}
288 	mp->mp = modp;
289 	return (0);
290 }
291 
292 /*
293  * modp->mod_modinfo has to be checked in these functions before
294  * mod_stub_info is accessed because it's not guranteed that all
295  * modules define mod_stub_info structures.
296  */
297 void
install_stubs(struct modctl * modp)298 install_stubs(struct modctl *modp)
299 {
300 	struct mod_stub_info *stub;
301 
302 	if (modp->mod_modinfo) {
303 		membar_producer();
304 		for (stub = modp->mod_modinfo->modm_stubs;
305 		    stub->mods_func_adr; stub++) {
306 			stub->mods_flag |= MODS_INSTALLED;
307 		}
308 		membar_producer();
309 	}
310 }
311 
312 void
uninstall_stubs(struct modctl * modp)313 uninstall_stubs(struct modctl *modp)
314 {
315 	struct mod_stub_info *stub;
316 
317 	if (modp->mod_modinfo) {
318 		membar_producer();
319 		for (stub = modp->mod_modinfo->modm_stubs;
320 		    stub->mods_func_adr; stub++) {
321 			stub->mods_flag &= ~MODS_INSTALLED;
322 		}
323 		membar_producer();
324 	}
325 }
326 
327 void
reset_stubs(struct modctl * modp)328 reset_stubs(struct modctl *modp)
329 {
330 	struct mod_stub_info *stub;
331 
332 	if (modp->mod_modinfo) {
333 		for (stub = modp->mod_modinfo->modm_stubs;
334 		    stub->mods_func_adr; stub++) {
335 			if (stub->mods_flag & (MODS_WEAK | MODS_NOUNLOAD))
336 				stub->mods_func_adr =
337 				    (uintptr_t)stub->mods_errfcn;
338 			else
339 				stub->mods_func_adr =
340 				    (uintptr_t)mod_hold_stub;
341 		}
342 		modp->mod_modinfo->mp = NULL;
343 	}
344 }
345 
346 struct modctl *
mod_getctl(struct modlinkage * modlp)347 mod_getctl(struct modlinkage *modlp)
348 {
349 	struct modctl	*modp;
350 
351 	mutex_enter(&mod_lock);
352 	modp = &modules;
353 	do {
354 		if (modp->mod_linkage == modlp) {
355 			mutex_exit(&mod_lock);
356 			return (modp);
357 		}
358 	} while ((modp = modp->mod_next) != &modules);
359 	mutex_exit(&mod_lock);
360 	return (NULL);
361 }
362 
363 
364 /*
365  * Attach driver.conf info to devnames for a driver
366  */
367 struct par_list *
impl_make_parlist(major_t major)368 impl_make_parlist(major_t major)
369 {
370 	int err;
371 	struct par_list *pl = NULL, *tmp;
372 	ddi_prop_t *props = NULL;
373 	char *confname, *drvname;
374 	struct devnames *dnp;
375 
376 	dnp = &devnamesp[major];
377 
378 	ASSERT(mutex_owned(&dnp->dn_lock));
379 
380 	/*
381 	 * If .conf file already parsed or driver removed, just return.
382 	 * May return NULL.
383 	 */
384 	if (dnp->dn_flags & (DN_CONF_PARSED | DN_DRIVER_REMOVED))
385 		return (dnp->dn_pl);
386 
387 	drvname = mod_major_to_name(major);
388 	if (drvname == NULL)
389 		return (NULL);
390 
391 	confname = kmem_alloc(MAXNAMELEN, KM_SLEEP);
392 	(void) snprintf(confname, MAXNAMELEN, "drv/%s.conf", drvname);
393 	err = hwc_parse(confname, &pl, &props);
394 	kmem_free(confname, MAXNAMELEN);
395 	if (err)	/* file doesn't exist */
396 		return (NULL);
397 
398 	/*
399 	 * If there are global properties, reference it from dnp.
400 	 */
401 	if (props)
402 		dnp->dn_global_prop_ptr = i_ddi_prop_list_create(props);
403 
404 	/*
405 	 * Hash specs to be looked up by nexus drivers
406 	 */
407 	tmp = pl;
408 	while (tmp) {
409 		(void) hwc_hash(tmp->par_specs, major);
410 		tmp = tmp->par_next;
411 	}
412 
413 	if (!i_ddi_io_initialized()) {
414 		if (i_ddi_prop_search(DDI_DEV_T_ANY, DDI_FORCEATTACH,
415 		    DDI_PROP_TYPE_INT, &props))
416 			dnp->dn_flags |= DN_FORCE_ATTACH;
417 		if (i_ddi_prop_search(DDI_DEV_T_ANY, DDI_OPEN_RETURNS_EINTR,
418 		    DDI_PROP_TYPE_INT, &props))
419 			dnp->dn_flags |= DN_OPEN_RETURNS_EINTR;
420 		if (i_ddi_prop_search(DDI_DEV_T_ANY, "scsi-size-clean",
421 		    DDI_PROP_TYPE_INT, &props))
422 			dnp->dn_flags |= DN_SCSI_SIZE_CLEAN;
423 	}
424 
425 	if (i_ddi_prop_search(DDI_DEV_T_ANY, DDI_VHCI_CLASS,
426 	    DDI_PROP_TYPE_STRING, &props))
427 		dnp->dn_flags |= DN_PHCI_DRIVER;
428 
429 	if (i_ddi_prop_search(DDI_DEV_T_ANY, DDI_DEVID_REGISTRANT,
430 	    DDI_PROP_TYPE_INT, &props)) {
431 		dnp->dn_flags |= DN_DEVID_REGISTRANT;
432 	}
433 
434 	dnp->dn_flags |= DN_CONF_PARSED;
435 	dnp->dn_pl = pl;
436 	return (pl);
437 }
438 
439 /*
440  * Destroy driver.conf info in devnames array for a driver
441  */
442 int
impl_free_parlist(major_t major)443 impl_free_parlist(major_t major)
444 {
445 	struct par_list *pl;
446 	struct devnames *dnp = &devnamesp[major];
447 
448 	/*
449 	 * Unref driver global property list. Don't destroy it
450 	 * because some instances may still be referencing it.
451 	 * The property list will be freed when the last ref
452 	 * goes away.
453 	 */
454 	if (dnp->dn_global_prop_ptr) {
455 		i_ddi_prop_list_rele(dnp->dn_global_prop_ptr, dnp);
456 		dnp->dn_global_prop_ptr = NULL;
457 	}
458 
459 	/*
460 	 * remove specs from hash table
461 	 */
462 	for (pl = dnp->dn_pl; pl; pl = pl->par_next)
463 		hwc_unhash(pl->par_specs);
464 
465 	impl_delete_par_list(dnp->dn_pl);
466 	dnp->dn_pl = NULL;
467 	dnp->dn_flags &= ~DN_CONF_PARSED;
468 	return (0);
469 }
470 
471 struct bind *mb_hashtab[MOD_BIND_HASHSIZE];
472 struct bind *sb_hashtab[MOD_BIND_HASHSIZE];
473 
474 static int
nm_hash(char * name)475 nm_hash(char *name)
476 {
477 	char c;
478 	int hash = 0;
479 
480 	for (c = *name++; c; c = *name++)
481 		hash ^= c;
482 
483 	return (hash & MOD_BIND_HASHMASK);
484 }
485 
486 void
clear_binding_hash(struct bind ** bhash)487 clear_binding_hash(struct bind **bhash)
488 {
489 	int i;
490 	struct bind *bp, *bp1;
491 
492 	for (i = 0; i < MOD_BIND_HASHSIZE; i++) {
493 		bp = bhash[i];
494 		while (bp != NULL) {
495 			kmem_free(bp->b_name, strlen(bp->b_name) + 1);
496 			if (bp->b_bind_name) {
497 				kmem_free(bp->b_bind_name,
498 				    strlen(bp->b_bind_name) + 1);
499 			}
500 			bp1 = bp;
501 			bp = bp->b_next;
502 			kmem_free(bp1, sizeof (struct bind));
503 		}
504 		bhash[i] = NULL;
505 	}
506 }
507 
508 /* Find an mbind by name match (caller can ask for deleted match) */
509 static struct bind *
find_mbind(char * name,struct bind ** hashtab,int deleted)510 find_mbind(char *name, struct bind **hashtab, int deleted)
511 {
512 	struct bind	*mb;
513 
514 	for (mb = hashtab[nm_hash(name)]; mb; mb = mb->b_next) {
515 		if (deleted && (mb->b_num >= 0))
516 			continue;			/* skip active */
517 		if (!deleted && (mb->b_num < 0))
518 			continue;			/* skip deleted */
519 
520 		/* return if name matches */
521 		if (strcmp(name, mb->b_name) == 0) {
522 			break;
523 		}
524 	}
525 	return (mb);
526 }
527 
528 /*
529  * Create an entry for the given (name, major, bind_name) tuple in the
530  * hash table supplied.  Reject the attempt to do so if 'name' is already
531  * in the hash table.
532  *
533  * Does not provide synchronization, so use only during boot or with
534  * externally provided locking.
535  */
536 int
make_mbind(char * name,int num,char * bind_name,struct bind ** hashtab)537 make_mbind(char *name, int num, char *bind_name, struct bind **hashtab)
538 {
539 	struct bind	*mb;
540 	struct bind	**pmb;
541 
542 	ASSERT(hashtab != NULL);
543 	ASSERT(num >= 0);
544 
545 	/* Fail if the key being added is already established */
546 	if (find_mbind(name, hashtab, 0) != NULL)
547 		return (-1);
548 
549 	/* Allocate new mbind */
550 	mb = kmem_zalloc(sizeof (struct bind), KM_SLEEP);
551 	mb->b_name = i_ddi_strdup(name, KM_SLEEP);
552 	mb->b_num = num;
553 	if (bind_name != NULL)
554 		mb->b_bind_name = i_ddi_strdup(bind_name, KM_SLEEP);
555 
556 	/* Insert at head of hash */
557 	pmb = &hashtab[nm_hash(name)];
558 	mb->b_next = *pmb;
559 	*pmb = mb;
560 	return (0);
561 }
562 
563 /*
564  * Delete a binding from a binding-hash. Since there is no locking we
565  * delete an mbind by making its b_num negative. We also support find_mbind
566  * of deleted entries, so we still need deleted items on the list.
567  */
568 void
delete_mbind(char * name,struct bind ** hashtab)569 delete_mbind(char *name, struct bind **hashtab)
570 {
571 	struct bind	*mb;
572 
573 	for (mb = hashtab[nm_hash(name)]; mb; mb = mb->b_next) {
574 		if ((mb->b_num >= 0) && (strcmp(name, mb->b_name) == 0)) {
575 			/* delete by making b_num negative */
576 			if (moddebug & MODDEBUG_BINDING) {
577 				cmn_err(CE_CONT, "mbind: %s %d deleted\n",
578 				    name, mb->b_num);
579 			}
580 			mb->b_num = -mb->b_num;
581 			break;
582 		}
583 	}
584 }
585 
586 /*
587  * Delete all items in an mbind associated with specified num.
588  * An example would be rem_drv deleting all aliases associated with a
589  * driver major number.
590  */
591 void
purge_mbind(int num,struct bind ** hashtab)592 purge_mbind(int num, struct bind **hashtab)
593 {
594 	int		i;
595 	struct bind	*mb;
596 
597 	/* search all hash lists for items that associated with 'num' */
598 	for (i = 0; i < MOD_BIND_HASHSIZE; i++) {
599 		for (mb = hashtab[i]; mb; mb = mb->b_next) {
600 			if (mb->b_num == num) {
601 				if (moddebug & MODDEBUG_BINDING)
602 					cmn_err(CE_CONT,
603 					    "mbind: %s %d purged\n",
604 					    mb->b_name, num);
605 				/* purge by changing the sign */
606 				mb->b_num = -num;
607 			}
608 		}
609 	}
610 }
611 
612 major_t
mod_name_to_major(char * name)613 mod_name_to_major(char *name)
614 {
615 	struct bind	*mbind;
616 	major_t		maj;
617 
618 	/* Search for non-deleted match. */
619 	if ((mbind = find_mbind(name, mb_hashtab, 0)) != NULL) {
620 		if (moddebug & MODDEBUG_BINDING) {
621 			if (find_mbind(name, mb_hashtab, 1))
622 				cmn_err(CE_CONT,
623 				    "'%s' has deleted match too\n", name);
624 		}
625 		return ((major_t)mbind->b_num);
626 	}
627 
628 	/*
629 	 * Search for deleted match: We may find that we have dependencies
630 	 * on drivers that have been deleted (but the old driver may still
631 	 * be bound to a node). These callers should be converted to use
632 	 * ddi_driver_major(i.e. devi_major).
633 	 */
634 	if (moddebug & MODDEBUG_BINDING) {
635 		if ((mbind = find_mbind(name, mb_hashtab, 1)) != NULL) {
636 			maj = (major_t)(-(mbind->b_num));
637 			cmn_err(CE_CONT, "Reference to deleted alias '%s' %d\n",
638 			    name, maj);
639 		}
640 	}
641 
642 	return (DDI_MAJOR_T_NONE);
643 }
644 
645 char *
mod_major_to_name(major_t major)646 mod_major_to_name(major_t major)
647 {
648 	if (!driver_installed(major))
649 		return (NULL);
650 	return ((&devnamesp[major])->dn_name);
651 }
652 
653 /*
654  * Set up the devnames array.  Error check for duplicate entries.
655  */
656 void
init_devnamesp(int size)657 init_devnamesp(int size)
658 {
659 	int hshndx;
660 	struct bind *bp;
661 	static char dupwarn[] =
662 	    "!Device entry \"%s %d\" conflicts with previous entry \"%s %d\" "
663 	    "in /etc/name_to_major.";
664 	static char badmaj[] = "The major number %u is invalid.";
665 
666 	ASSERT(size <= L_MAXMAJ32 && size > 0);
667 
668 	/*
669 	 * Allocate the devnames array.  All mutexes and cv's will be
670 	 * automagically initialized.
671 	 */
672 	devnamesp = kobj_zalloc(size * sizeof (struct devnames), KM_SLEEP);
673 
674 	/*
675 	 * Stick the contents of mb_hashtab into the devnames array.  Warn if
676 	 * two hash entries correspond to the same major number, or if a
677 	 * major number is out of range.
678 	 */
679 	for (hshndx = 0; hshndx < MOD_BIND_HASHSIZE; hshndx++) {
680 		for (bp = mb_hashtab[hshndx]; bp; bp = bp->b_next) {
681 			if (make_devname(bp->b_name,
682 			    (major_t)bp->b_num, 0) != 0) {
683 				/*
684 				 * If there is not an entry at b_num already,
685 				 * then this must be a bad major number.
686 				 */
687 				char *nm = mod_major_to_name(bp->b_num);
688 				if (nm == NULL) {
689 					cmn_err(CE_WARN, badmaj,
690 					    (uint_t)bp->b_num);
691 				} else {
692 					cmn_err(CE_WARN, dupwarn, bp->b_name,
693 					    bp->b_num, nm, bp->b_num);
694 				}
695 			}
696 		}
697 	}
698 
699 	/* Initialize hash table for hwc_spec's */
700 	hwc_hash_init();
701 }
702 
703 int
make_devname(char * name,major_t major,int dn_flags)704 make_devname(char *name, major_t major, int dn_flags)
705 {
706 	struct devnames *dnp;
707 	char *copy;
708 
709 	/*
710 	 * Until on-disk support for major nums > 14 bits arrives, fail
711 	 * any major numbers that are too big.
712 	 */
713 	if (major > L_MAXMAJ32)
714 		return (EINVAL);
715 
716 	dnp = &devnamesp[major];
717 	LOCK_DEV_OPS(&dnp->dn_lock);
718 	if (dnp->dn_name) {
719 		if (strcmp(dnp->dn_name, name) != 0) {
720 			/* Another driver already here */
721 			UNLOCK_DEV_OPS(&dnp->dn_lock);
722 			return (EINVAL);
723 		}
724 		/* Adding back a removed driver */
725 		dnp->dn_flags &= ~DN_DRIVER_REMOVED;
726 		dnp->dn_flags |= dn_flags;
727 		UNLOCK_DEV_OPS(&dnp->dn_lock);
728 		return (0);
729 	}
730 
731 	/*
732 	 * Check if flag is taken by getudev()
733 	 */
734 	if (dnp->dn_flags & DN_TAKEN_GETUDEV) {
735 		UNLOCK_DEV_OPS(&dnp->dn_lock);
736 		return (EINVAL);
737 	}
738 
739 	copy = kmem_alloc(strlen(name) + 1, KM_SLEEP);
740 	(void) strcpy(copy, name);
741 
742 	/* Make sure string is copied before setting dn_name */
743 	membar_producer();
744 	dnp->dn_name = copy;
745 	dnp->dn_flags = dn_flags;
746 	UNLOCK_DEV_OPS(&dnp->dn_lock);
747 	return (0);
748 }
749 
750 /*
751  * Set up the syscallnames array.
752  */
753 void
init_syscallnames(int size)754 init_syscallnames(int size)
755 {
756 	int hshndx;
757 	struct bind *bp;
758 
759 	syscallnames = kobj_zalloc(size * sizeof (char *), KM_SLEEP);
760 
761 	for (hshndx = 0; hshndx < MOD_BIND_HASHSIZE; hshndx++) {
762 		for (bp = sb_hashtab[hshndx]; bp; bp = bp->b_next) {
763 			if (bp->b_num < 0 || bp->b_num >= size) {
764 				cmn_err(CE_WARN,
765 				    "!Couldn't add system call \"%s %d\". "
766 				    "Value out of range (0..%d) in "
767 				    "/etc/name_to_sysnum.",
768 				    bp->b_name, bp->b_num, size - 1);
769 				continue;
770 			}
771 			make_syscallname(bp->b_name, bp->b_num);
772 		}
773 	}
774 }
775 
776 static void
make_syscallname(char * name,int sysno)777 make_syscallname(char *name, int sysno)
778 {
779 	char **cp = &syscallnames[sysno];
780 
781 	if (*cp != NULL) {
782 		cmn_err(CE_WARN, "!Couldn't add system call \"%s %d\". "
783 		    "It conflicts with \"%s %d\" in /etc/name_to_sysnum.",
784 		    name, sysno, *cp, sysno);
785 		return;
786 	}
787 	*cp = kmem_alloc(strlen(name) + 1, KM_SLEEP);
788 	(void) strcpy(*cp, name);
789 }
790 
791 /*
792  * Given a system call name, get its number.
793  */
794 int
mod_getsysnum(char * name)795 mod_getsysnum(char *name)
796 {
797 	struct bind *mbind;
798 
799 	if ((mbind = find_mbind(name, sb_hashtab, 0)) != NULL)
800 		return (mbind->b_num);
801 
802 	return (-1);
803 }
804 
805 /*
806  * Given a system call number, get the system call name.
807  */
808 char *
mod_getsysname(int sysnum)809 mod_getsysname(int sysnum)
810 {
811 	return (syscallnames[sysnum]);
812 }
813 
814 /*
815  * Find the name of the module containing the specified pc.
816  * Returns the name on success, "<unknown>" on failure.
817  * No mod_lock locking is required because things are never deleted from
818  * the &modules list.
819  */
820 char *
mod_containing_pc(caddr_t pc)821 mod_containing_pc(caddr_t pc)
822 {
823 	struct modctl	*mcp = &modules;
824 
825 	do {
826 		if (mcp->mod_mp != NULL &&
827 		    (size_t)pc - (size_t)mcp->mod_text < mcp->mod_text_size)
828 			return (mcp->mod_modname);
829 	} while ((mcp = mcp->mod_next) != &modules);
830 	return ("<unknown>");
831 }
832 
833 /*
834  * Hash tables for hwc_spec
835  *
836  * The purpose of these hash tables are to allow the framework to discover
837  * all possible .conf children for a given nexus. There are two hash tables.
838  * One is hashed based on parent name, the on the class name. Each
839  * driver.conf file translates to a list of hwc_spec's. Adding and
840  * removing the entire list is an atomic operation, protected by
841  * the hwc_hash_lock.
842  *
843  * What we get from all the hashing is the function hwc_get_child_spec().
844  */
845 #define	HWC_SPEC_HASHSIZE	(1 << 6)	/* 64 */
846 
847 static mod_hash_t *hwc_par_hash;	/* hash by parent name */
848 static mod_hash_t *hwc_class_hash;	/* hash by class name */
849 static kmutex_t hwc_hash_lock;		/* lock protecting hwc hashes */
850 
851 /*
852  * Initialize hash tables for parent and class specs
853  */
854 static void
hwc_hash_init()855 hwc_hash_init()
856 {
857 	hwc_par_hash = mod_hash_create_strhash("hwc parent spec hash",
858 	    HWC_SPEC_HASHSIZE, mod_hash_null_valdtor);
859 	hwc_class_hash = mod_hash_create_strhash("hwc class spec hash",
860 	    HWC_SPEC_HASHSIZE, mod_hash_null_valdtor);
861 }
862 
863 /*
864  * Insert a spec into hash table. hwc_hash_lock must be held
865  */
866 static void
hwc_hash_insert(struct hwc_spec * spec,char * name,mod_hash_t * hash)867 hwc_hash_insert(struct hwc_spec *spec, char *name, mod_hash_t *hash)
868 {
869 	mod_hash_key_t key;
870 	struct hwc_spec *entry = NULL;
871 
872 	ASSERT(name != NULL);
873 
874 	if (mod_hash_find(hash, (mod_hash_key_t)name,
875 	    (mod_hash_val_t)&entry) != 0) {
876 		/* Name doesn't exist, insert a new key */
877 		key = kmem_alloc(strlen(name) + 1, KM_SLEEP);
878 		(void) strcpy((char *)key, name);
879 		if (mod_hash_insert(hash, key, (mod_hash_val_t)spec) != 0) {
880 			kmem_free(key, strlen(name) + 1);
881 			cmn_err(CE_WARN, "hwc hash state inconsistent");
882 		}
883 		return;
884 	}
885 
886 	/*
887 	 * Name is already present, append spec to the list.
888 	 * This is the case when driver.conf specifies multiple
889 	 * nodes under a single parent or class.
890 	 */
891 	while (entry->hwc_hash_next)
892 		entry = entry->hwc_hash_next;
893 	entry->hwc_hash_next = spec;
894 }
895 
896 /*
897  * Remove a spec entry from spec hash table, the spec itself is
898  * destroyed external to this function.
899  */
900 static void
hwc_hash_remove(struct hwc_spec * spec,char * name,mod_hash_t * hash)901 hwc_hash_remove(struct hwc_spec *spec, char *name, mod_hash_t *hash)
902 {
903 	char *key;
904 	struct hwc_spec *entry;
905 
906 	ASSERT(name != NULL);
907 
908 	if (mod_hash_find(hash, (mod_hash_key_t)name,
909 	    (mod_hash_val_t)&entry) != 0) {
910 		return;	/* name not found in hash */
911 	}
912 
913 	/*
914 	 * If the head is the spec to be removed, either destroy the
915 	 * entry or replace it with the remaining list.
916 	 */
917 	if (entry == spec) {
918 		if (spec->hwc_hash_next == NULL) {
919 			(void) mod_hash_destroy(hash, (mod_hash_key_t)name);
920 			return;
921 		}
922 		key = kmem_alloc(strlen(name) + 1, KM_SLEEP);
923 		(void) strcpy(key, name);
924 		(void) mod_hash_replace(hash, (mod_hash_key_t)key,
925 		    (mod_hash_val_t)spec->hwc_hash_next);
926 		spec->hwc_hash_next = NULL;
927 		return;
928 	}
929 
930 	/*
931 	 * If the head is not the one, look for the spec in the
932 	 * hwc_hash_next linkage.
933 	 */
934 	while (entry->hwc_hash_next && (entry->hwc_hash_next != spec))
935 		entry = entry->hwc_hash_next;
936 
937 	if (entry->hwc_hash_next) {
938 		entry->hwc_hash_next = spec->hwc_hash_next;
939 		spec->hwc_hash_next = NULL;
940 	}
941 }
942 
943 /*
944  * Hash a list of specs based on either parent name or class name
945  */
946 static void
hwc_hash(struct hwc_spec * spec_list,major_t major)947 hwc_hash(struct hwc_spec *spec_list, major_t major)
948 {
949 	struct hwc_spec *spec = spec_list;
950 
951 	mutex_enter(&hwc_hash_lock);
952 	while (spec) {
953 		/* Put driver major here so parent can find it */
954 		spec->hwc_major = major;
955 
956 		if (spec->hwc_parent_name != NULL) {
957 			hwc_hash_insert(spec, spec->hwc_parent_name,
958 			    hwc_par_hash);
959 		} else if (spec->hwc_class_name != NULL) {
960 			hwc_hash_insert(spec, spec->hwc_class_name,
961 			    hwc_class_hash);
962 		} else {
963 			cmn_err(CE_WARN,
964 			    "hwc_hash: No class or parent specified");
965 		}
966 		spec = spec->hwc_next;
967 	}
968 	mutex_exit(&hwc_hash_lock);
969 }
970 
971 /*
972  * Remove a list of specs from hash tables. Don't destroy the specs yet.
973  */
974 static void
hwc_unhash(struct hwc_spec * spec_list)975 hwc_unhash(struct hwc_spec *spec_list)
976 {
977 	struct hwc_spec *spec = spec_list;
978 
979 	mutex_enter(&hwc_hash_lock);
980 	while (spec) {
981 		if (spec->hwc_parent_name != NULL) {
982 			hwc_hash_remove(spec, spec->hwc_parent_name,
983 			    hwc_par_hash);
984 		} else if (spec->hwc_class_name != NULL) {
985 			hwc_hash_remove(spec, spec->hwc_class_name,
986 			    hwc_class_hash);
987 		} else {
988 			cmn_err(CE_WARN,
989 			    "hwc_unhash: No class or parent specified");
990 		}
991 		spec = spec->hwc_next;
992 	}
993 	mutex_exit(&hwc_hash_lock);
994 }
995 
996 /*
997  * Make a copy of specs in a hash entry and add to the end of listp.
998  * Called by nexus to locate a list of child specs.
999  *
1000  * entry is a list of hwc_spec chained together with hwc_hash_next.
1001  * listp points to list chained together with hwc_next.
1002  */
1003 static void
hwc_spec_add(struct hwc_spec ** listp,struct hwc_spec * entry,major_t match_major)1004 hwc_spec_add(struct hwc_spec **listp, struct hwc_spec *entry,
1005     major_t match_major)
1006 {
1007 	/* Find the tail of the list */
1008 	while (*listp)
1009 		listp = &(*listp)->hwc_next;
1010 
1011 	while (entry) {
1012 		struct hwc_spec *spec;
1013 
1014 		if ((match_major != DDI_MAJOR_T_NONE) &&
1015 		    (match_major != entry->hwc_major)) {
1016 			entry = entry->hwc_hash_next;
1017 			continue;
1018 		}
1019 
1020 		/*
1021 		 * Allocate spec and copy the content of entry.
1022 		 * No need to copy class/parent name since caller
1023 		 * already knows the parent dip.
1024 		 */
1025 		spec = kmem_zalloc(sizeof (*spec), KM_SLEEP);
1026 		spec->hwc_devi_name = i_ddi_strdup(
1027 		    entry->hwc_devi_name, KM_SLEEP);
1028 		spec->hwc_major = entry->hwc_major;
1029 		spec->hwc_devi_sys_prop_ptr = i_ddi_prop_list_dup(
1030 		    entry->hwc_devi_sys_prop_ptr, KM_SLEEP);
1031 
1032 		*listp = spec;
1033 		listp = &spec->hwc_next;
1034 		entry = entry->hwc_hash_next;
1035 	}
1036 }
1037 
1038 /*
1039  * Given a dip, find the list of child .conf specs from most specific
1040  * (parent pathname) to least specific (class name).
1041  *
1042  * This function allows top-down loading to be implemented without
1043  * changing the format of driver.conf file.
1044  */
1045 struct hwc_spec *
hwc_get_child_spec(dev_info_t * dip,major_t match_major)1046 hwc_get_child_spec(dev_info_t *dip, major_t match_major)
1047 {
1048 	extern char *i_ddi_parname(dev_info_t *, char *);
1049 	extern int i_ddi_get_exported_classes(dev_info_t *, char ***);
1050 	extern void i_ddi_free_exported_classes(char **, int);
1051 
1052 	int i, nclass;
1053 	char **classes;
1054 	struct hwc_spec *list = NULL;
1055 	mod_hash_val_t val;
1056 	char *parname, *parname_buf;
1057 	char *deviname, *deviname_buf;
1058 	char *pathname, *pathname_buf;
1059 	char *bindname;
1060 	char *drvname;
1061 
1062 	pathname_buf = kmem_alloc(3 * MAXPATHLEN, KM_SLEEP);
1063 	deviname_buf = pathname_buf + MAXPATHLEN;
1064 	parname_buf = pathname_buf + (2 * MAXPATHLEN);
1065 
1066 	mutex_enter(&hwc_hash_lock);
1067 
1068 	/*
1069 	 * Lookup based on full path.
1070 	 * In the case of root node, ddi_pathname would return
1071 	 * null string so just skip calling it.
1072 	 * As the pathname always begins with /, no simpler
1073 	 * name can duplicate it.
1074 	 */
1075 	pathname = (dip == ddi_root_node()) ? "/" :
1076 	    ddi_pathname(dip, pathname_buf);
1077 	ASSERT(pathname != NULL);
1078 	ASSERT(*pathname == '/');
1079 
1080 	if (mod_hash_find(hwc_par_hash, (mod_hash_key_t)pathname, &val) == 0) {
1081 		hwc_spec_add(&list, (struct hwc_spec *)val, match_major);
1082 	}
1083 
1084 	/*
1085 	 * Lookup nodename@address.
1086 	 * Note deviname cannot match pathname.
1087 	 */
1088 	deviname = ddi_deviname(dip, deviname_buf);
1089 	if (*deviname != '\0') {
1090 		/*
1091 		 * Skip leading / returned by ddi_deviname.
1092 		 */
1093 		ASSERT(*deviname == '/');
1094 		deviname++;
1095 		if ((*deviname != '\0') && (mod_hash_find(hwc_par_hash,
1096 		    (mod_hash_key_t)deviname, &val) == 0))
1097 			hwc_spec_add(&list,
1098 			    (struct hwc_spec *)val, match_major);
1099 	}
1100 
1101 	/*
1102 	 * Lookup bindingname@address.
1103 	 * Take care not to perform duplicate lookups.
1104 	 */
1105 	parname = i_ddi_parname(dip, parname_buf);
1106 	if (*parname != '\0') {
1107 		ASSERT(*parname != '/');
1108 		if ((strcmp(parname, deviname) != 0) &&
1109 		    (mod_hash_find(hwc_par_hash,
1110 		    (mod_hash_key_t)parname, &val) == 0)) {
1111 			hwc_spec_add(&list,
1112 			    (struct hwc_spec *)val, match_major);
1113 		}
1114 	}
1115 
1116 	/*
1117 	 * Lookup driver binding name
1118 	 */
1119 	bindname = ddi_binding_name(dip);
1120 	ASSERT(*bindname != '/');
1121 	if ((strcmp(bindname, parname) != 0) &&
1122 	    (strcmp(bindname, deviname) != 0) &&
1123 	    (mod_hash_find(hwc_par_hash, (mod_hash_key_t)bindname, &val) == 0))
1124 		hwc_spec_add(&list, (struct hwc_spec *)val, match_major);
1125 
1126 	/*
1127 	 * Lookup driver name
1128 	 */
1129 	drvname = (char *)ddi_driver_name(dip);
1130 	ASSERT(*drvname != '/');
1131 	if ((strcmp(drvname, bindname) != 0) &&
1132 	    (strcmp(drvname, parname) != 0) &&
1133 	    (strcmp(drvname, deviname) != 0) &&
1134 	    (mod_hash_find(hwc_par_hash, (mod_hash_key_t)drvname, &val) == 0))
1135 		hwc_spec_add(&list, (struct hwc_spec *)val, match_major);
1136 
1137 	kmem_free(pathname_buf, 3 * MAXPATHLEN);
1138 
1139 	/*
1140 	 * Lookup classes exported by this node and lookup the
1141 	 * class hash table for all .conf specs
1142 	 */
1143 	nclass = i_ddi_get_exported_classes(dip, &classes);
1144 	for (i = 0; i < nclass; i++) {
1145 		if (mod_hash_find(hwc_class_hash, (mod_hash_key_t)classes[i],
1146 		    &val) == 0)
1147 			hwc_spec_add(&list, (struct hwc_spec *)val,
1148 			    match_major);
1149 	}
1150 	i_ddi_free_exported_classes(classes, nclass);
1151 
1152 	mutex_exit(&hwc_hash_lock);
1153 	return (list);
1154 }
1155