xref: /freebsd/sys/geom/part/g_part.c (revision 830940567b49bb0c08dfaed40418999e76616909)
1 /*-
2  * Copyright (c) 2002, 2005-2009 Marcel Moolenaar
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/bio.h>
32 #include <sys/diskmbr.h>
33 #include <sys/endian.h>
34 #include <sys/kernel.h>
35 #include <sys/kobj.h>
36 #include <sys/limits.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/mutex.h>
40 #include <sys/queue.h>
41 #include <sys/sbuf.h>
42 #include <sys/systm.h>
43 #include <sys/uuid.h>
44 #include <geom/geom.h>
45 #include <geom/geom_ctl.h>
46 #include <geom/geom_int.h>
47 #include <geom/part/g_part.h>
48 
49 #include "g_part_if.h"
50 
51 #ifndef _PATH_DEV
52 #define _PATH_DEV "/dev/"
53 #endif
54 
55 static kobj_method_t g_part_null_methods[] = {
56 	{ 0, 0 }
57 };
58 
59 static struct g_part_scheme g_part_null_scheme = {
60 	"(none)",
61 	g_part_null_methods,
62 	sizeof(struct g_part_table),
63 };
64 
65 TAILQ_HEAD(, g_part_scheme) g_part_schemes =
66     TAILQ_HEAD_INITIALIZER(g_part_schemes);
67 
68 struct g_part_alias_list {
69 	const char *lexeme;
70 	enum g_part_alias alias;
71 } g_part_alias_list[G_PART_ALIAS_COUNT] = {
72 	{ "apple-hfs", G_PART_ALIAS_APPLE_HFS },
73 	{ "efi", G_PART_ALIAS_EFI },
74 	{ "freebsd", G_PART_ALIAS_FREEBSD },
75 	{ "freebsd-boot", G_PART_ALIAS_FREEBSD_BOOT },
76 	{ "freebsd-swap", G_PART_ALIAS_FREEBSD_SWAP },
77 	{ "freebsd-ufs", G_PART_ALIAS_FREEBSD_UFS },
78 	{ "freebsd-vinum", G_PART_ALIAS_FREEBSD_VINUM },
79 	{ "freebsd-zfs", G_PART_ALIAS_FREEBSD_ZFS },
80 	{ "mbr", G_PART_ALIAS_MBR }
81 };
82 
83 /*
84  * The GEOM partitioning class.
85  */
86 static g_ctl_req_t g_part_ctlreq;
87 static g_ctl_destroy_geom_t g_part_destroy_geom;
88 static g_fini_t g_part_fini;
89 static g_init_t g_part_init;
90 static g_taste_t g_part_taste;
91 
92 static g_access_t g_part_access;
93 static g_dumpconf_t g_part_dumpconf;
94 static g_orphan_t g_part_orphan;
95 static g_spoiled_t g_part_spoiled;
96 static g_start_t g_part_start;
97 
98 static struct g_class g_part_class = {
99 	.name = "PART",
100 	.version = G_VERSION,
101 	/* Class methods. */
102 	.ctlreq = g_part_ctlreq,
103 	.destroy_geom = g_part_destroy_geom,
104 	.fini = g_part_fini,
105 	.init = g_part_init,
106 	.taste = g_part_taste,
107 	/* Geom methods. */
108 	.access = g_part_access,
109 	.dumpconf = g_part_dumpconf,
110 	.orphan = g_part_orphan,
111 	.spoiled = g_part_spoiled,
112 	.start = g_part_start,
113 };
114 
115 DECLARE_GEOM_CLASS(g_part_class, g_part);
116 
117 /*
118  * Support functions.
119  */
120 
121 static void g_part_wither(struct g_geom *, int);
122 
123 const char *
124 g_part_alias_name(enum g_part_alias alias)
125 {
126 	int i;
127 
128 	for (i = 0; i < G_PART_ALIAS_COUNT; i++) {
129 		if (g_part_alias_list[i].alias != alias)
130 			continue;
131 		return (g_part_alias_list[i].lexeme);
132 	}
133 
134 	return (NULL);
135 }
136 
137 void
138 g_part_geometry_heads(off_t blocks, u_int sectors, off_t *bestchs,
139     u_int *bestheads)
140 {
141 	static u_int candidate_heads[] = { 1, 2, 16, 32, 64, 128, 255, 0 };
142 	off_t chs, cylinders;
143 	u_int heads;
144 	int idx;
145 
146 	*bestchs = 0;
147 	*bestheads = 0;
148 	for (idx = 0; candidate_heads[idx] != 0; idx++) {
149 		heads = candidate_heads[idx];
150 		cylinders = blocks / heads / sectors;
151 		if (cylinders < heads || cylinders < sectors)
152 			break;
153 		if (cylinders > 1023)
154 			continue;
155 		chs = cylinders * heads * sectors;
156 		if (chs > *bestchs || (chs == *bestchs && *bestheads == 1)) {
157 			*bestchs = chs;
158 			*bestheads = heads;
159 		}
160 	}
161 }
162 
163 static void
164 g_part_geometry(struct g_part_table *table, struct g_consumer *cp,
165     off_t blocks)
166 {
167 	static u_int candidate_sectors[] = { 1, 9, 17, 33, 63, 0 };
168 	off_t chs, bestchs;
169 	u_int heads, sectors;
170 	int idx;
171 
172 	if (g_getattr("GEOM::fwsectors", cp, &sectors) != 0 || sectors == 0 ||
173 	    g_getattr("GEOM::fwheads", cp, &heads) != 0 || heads == 0) {
174 		table->gpt_fixgeom = 0;
175 		table->gpt_heads = 0;
176 		table->gpt_sectors = 0;
177 		bestchs = 0;
178 		for (idx = 0; candidate_sectors[idx] != 0; idx++) {
179 			sectors = candidate_sectors[idx];
180 			g_part_geometry_heads(blocks, sectors, &chs, &heads);
181 			if (chs == 0)
182 				continue;
183 			/*
184 			 * Prefer a geometry with sectors > 1, but only if
185 			 * it doesn't bump down the numbver of heads to 1.
186 			 */
187 			if (chs > bestchs || (chs == bestchs && heads > 1 &&
188 			    table->gpt_sectors == 1)) {
189 				bestchs = chs;
190 				table->gpt_heads = heads;
191 				table->gpt_sectors = sectors;
192 			}
193 		}
194 		/*
195 		 * If we didn't find a geometry at all, then the disk is
196 		 * too big. This means we can use the maximum number of
197 		 * heads and sectors.
198 		 */
199 		if (bestchs == 0) {
200 			table->gpt_heads = 255;
201 			table->gpt_sectors = 63;
202 		}
203 	} else {
204 		table->gpt_fixgeom = 1;
205 		table->gpt_heads = heads;
206 		table->gpt_sectors = sectors;
207 	}
208 }
209 
210 struct g_part_entry *
211 g_part_new_entry(struct g_part_table *table, int index, quad_t start,
212     quad_t end)
213 {
214 	struct g_part_entry *entry, *last;
215 
216 	last = NULL;
217 	LIST_FOREACH(entry, &table->gpt_entry, gpe_entry) {
218 		if (entry->gpe_index == index)
219 			break;
220 		if (entry->gpe_index > index) {
221 			entry = NULL;
222 			break;
223 		}
224 		last = entry;
225 	}
226 	if (entry == NULL) {
227 		entry = g_malloc(table->gpt_scheme->gps_entrysz,
228 		    M_WAITOK | M_ZERO);
229 		entry->gpe_index = index;
230 		if (last == NULL)
231 			LIST_INSERT_HEAD(&table->gpt_entry, entry, gpe_entry);
232 		else
233 			LIST_INSERT_AFTER(last, entry, gpe_entry);
234 	} else
235 		entry->gpe_offset = 0;
236 	entry->gpe_start = start;
237 	entry->gpe_end = end;
238 	return (entry);
239 }
240 
241 static void
242 g_part_new_provider(struct g_geom *gp, struct g_part_table *table,
243     struct g_part_entry *entry)
244 {
245 	struct g_consumer *cp;
246 	struct g_provider *pp;
247 	struct sbuf *sb;
248 	off_t offset;
249 
250 	cp = LIST_FIRST(&gp->consumer);
251 	pp = cp->provider;
252 
253 	offset = entry->gpe_start * pp->sectorsize;
254 	if (entry->gpe_offset < offset)
255 		entry->gpe_offset = offset;
256 
257 	if (entry->gpe_pp == NULL) {
258 		sb = sbuf_new_auto();
259 		G_PART_FULLNAME(table, entry, sb, gp->name);
260 		sbuf_finish(sb);
261 		entry->gpe_pp = g_new_providerf(gp, "%s", sbuf_data(sb));
262 		sbuf_delete(sb);
263 		entry->gpe_pp->private = entry;		/* Close the circle. */
264 	}
265 	entry->gpe_pp->index = entry->gpe_index - 1;	/* index is 1-based. */
266 	entry->gpe_pp->mediasize = (entry->gpe_end - entry->gpe_start + 1) *
267 	    pp->sectorsize;
268 	entry->gpe_pp->mediasize -= entry->gpe_offset - offset;
269 	entry->gpe_pp->sectorsize = pp->sectorsize;
270 	entry->gpe_pp->flags = pp->flags & G_PF_CANDELETE;
271 	if (pp->stripesize > 0) {
272 		entry->gpe_pp->stripesize = pp->stripesize;
273 		entry->gpe_pp->stripeoffset = (pp->stripeoffset +
274 		    entry->gpe_offset) % pp->stripesize;
275 	}
276 	g_error_provider(entry->gpe_pp, 0);
277 }
278 
279 static int
280 g_part_parm_geom(const char *rawname, struct g_geom **v)
281 {
282 	struct g_geom *gp;
283 	const char *pname;
284 
285 	if (strncmp(rawname, _PATH_DEV, strlen(_PATH_DEV)) == 0)
286 		pname = rawname + strlen(_PATH_DEV);
287 	else
288 		pname = rawname;
289 	LIST_FOREACH(gp, &g_part_class.geom, geom) {
290 		if (!strcmp(pname, gp->name))
291 			break;
292 	}
293 	if (gp == NULL)
294 		return (EINVAL);
295 	*v = gp;
296 	return (0);
297 }
298 
299 static int
300 g_part_parm_provider(const char *pname, struct g_provider **v)
301 {
302 	struct g_provider *pp;
303 
304 	if (strncmp(pname, _PATH_DEV, strlen(_PATH_DEV)) == 0)
305 		pp = g_provider_by_name(pname + strlen(_PATH_DEV));
306 	else
307 		pp = g_provider_by_name(pname);
308 	if (pp == NULL)
309 		return (EINVAL);
310 	*v = pp;
311 	return (0);
312 }
313 
314 static int
315 g_part_parm_quad(const char *p, quad_t *v)
316 {
317 	char *x;
318 	quad_t q;
319 
320 	q = strtoq(p, &x, 0);
321 	if (*x != '\0' || q < 0)
322 		return (EINVAL);
323 	*v = q;
324 	return (0);
325 }
326 
327 static int
328 g_part_parm_scheme(const char *p, struct g_part_scheme **v)
329 {
330 	struct g_part_scheme *s;
331 
332 	TAILQ_FOREACH(s, &g_part_schemes, scheme_list) {
333 		if (s == &g_part_null_scheme)
334 			continue;
335 		if (!strcasecmp(s->name, p))
336 			break;
337 	}
338 	if (s == NULL)
339 		return (EINVAL);
340 	*v = s;
341 	return (0);
342 }
343 
344 static int
345 g_part_parm_str(const char *p, const char **v)
346 {
347 
348 	if (p[0] == '\0')
349 		return (EINVAL);
350 	*v = p;
351 	return (0);
352 }
353 
354 static int
355 g_part_parm_uint(const char *p, u_int *v)
356 {
357 	char *x;
358 	long l;
359 
360 	l = strtol(p, &x, 0);
361 	if (*x != '\0' || l < 0 || l > INT_MAX)
362 		return (EINVAL);
363 	*v = (unsigned int)l;
364 	return (0);
365 }
366 
367 static int
368 g_part_probe(struct g_geom *gp, struct g_consumer *cp, int depth)
369 {
370 	struct g_part_scheme *iter, *scheme;
371 	struct g_part_table *table;
372 	int pri, probe;
373 
374 	table = gp->softc;
375 	scheme = (table != NULL) ? table->gpt_scheme : NULL;
376 	pri = (scheme != NULL) ? G_PART_PROBE(table, cp) : INT_MIN;
377 	if (pri == 0)
378 		goto done;
379 	if (pri > 0) {	/* error */
380 		scheme = NULL;
381 		pri = INT_MIN;
382 	}
383 
384 	TAILQ_FOREACH(iter, &g_part_schemes, scheme_list) {
385 		if (iter == &g_part_null_scheme)
386 			continue;
387 		table = (void *)kobj_create((kobj_class_t)iter, M_GEOM,
388 		    M_WAITOK);
389 		table->gpt_gp = gp;
390 		table->gpt_scheme = iter;
391 		table->gpt_depth = depth;
392 		probe = G_PART_PROBE(table, cp);
393 		if (probe <= 0 && probe > pri) {
394 			pri = probe;
395 			scheme = iter;
396 			if (gp->softc != NULL)
397 				kobj_delete((kobj_t)gp->softc, M_GEOM);
398 			gp->softc = table;
399 			if (pri == 0)
400 				goto done;
401 		} else
402 			kobj_delete((kobj_t)table, M_GEOM);
403 	}
404 
405 done:
406 	return ((scheme == NULL) ? ENXIO : 0);
407 }
408 
409 /*
410  * Control request functions.
411  */
412 
413 static int
414 g_part_ctl_add(struct gctl_req *req, struct g_part_parms *gpp)
415 {
416 	struct g_geom *gp;
417 	struct g_provider *pp;
418 	struct g_part_entry *delent, *last, *entry;
419 	struct g_part_table *table;
420 	struct sbuf *sb;
421 	quad_t end;
422 	unsigned int index;
423 	int error;
424 
425 	gp = gpp->gpp_geom;
426 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, gp->name));
427 	g_topology_assert();
428 
429 	pp = LIST_FIRST(&gp->consumer)->provider;
430 	table = gp->softc;
431 	end = gpp->gpp_start + gpp->gpp_size - 1;
432 
433 	if (gpp->gpp_start < table->gpt_first ||
434 	    gpp->gpp_start > table->gpt_last) {
435 		gctl_error(req, "%d start '%jd'", EINVAL,
436 		    (intmax_t)gpp->gpp_start);
437 		return (EINVAL);
438 	}
439 	if (end < gpp->gpp_start || end > table->gpt_last) {
440 		gctl_error(req, "%d size '%jd'", EINVAL,
441 		    (intmax_t)gpp->gpp_size);
442 		return (EINVAL);
443 	}
444 	if (gpp->gpp_index > table->gpt_entries) {
445 		gctl_error(req, "%d index '%d'", EINVAL, gpp->gpp_index);
446 		return (EINVAL);
447 	}
448 
449 	delent = last = NULL;
450 	index = (gpp->gpp_index > 0) ? gpp->gpp_index : 1;
451 	LIST_FOREACH(entry, &table->gpt_entry, gpe_entry) {
452 		if (entry->gpe_deleted) {
453 			if (entry->gpe_index == index)
454 				delent = entry;
455 			continue;
456 		}
457 		if (entry->gpe_index == index)
458 			index = entry->gpe_index + 1;
459 		if (entry->gpe_index < index)
460 			last = entry;
461 		if (entry->gpe_internal)
462 			continue;
463 		if (gpp->gpp_start >= entry->gpe_start &&
464 		    gpp->gpp_start <= entry->gpe_end) {
465 			gctl_error(req, "%d start '%jd'", ENOSPC,
466 			    (intmax_t)gpp->gpp_start);
467 			return (ENOSPC);
468 		}
469 		if (end >= entry->gpe_start && end <= entry->gpe_end) {
470 			gctl_error(req, "%d end '%jd'", ENOSPC, (intmax_t)end);
471 			return (ENOSPC);
472 		}
473 		if (gpp->gpp_start < entry->gpe_start && end > entry->gpe_end) {
474 			gctl_error(req, "%d size '%jd'", ENOSPC,
475 			    (intmax_t)gpp->gpp_size);
476 			return (ENOSPC);
477 		}
478 	}
479 	if (gpp->gpp_index > 0 && index != gpp->gpp_index) {
480 		gctl_error(req, "%d index '%d'", EEXIST, gpp->gpp_index);
481 		return (EEXIST);
482 	}
483 
484 	entry = (delent == NULL) ? g_malloc(table->gpt_scheme->gps_entrysz,
485 	    M_WAITOK | M_ZERO) : delent;
486 	entry->gpe_index = index;
487 	entry->gpe_start = gpp->gpp_start;
488 	entry->gpe_end = end;
489 	error = G_PART_ADD(table, entry, gpp);
490 	if (error) {
491 		gctl_error(req, "%d", error);
492 		if (delent == NULL)
493 			g_free(entry);
494 		return (error);
495 	}
496 	if (delent == NULL) {
497 		if (last == NULL)
498 			LIST_INSERT_HEAD(&table->gpt_entry, entry, gpe_entry);
499 		else
500 			LIST_INSERT_AFTER(last, entry, gpe_entry);
501 		entry->gpe_created = 1;
502 	} else {
503 		entry->gpe_deleted = 0;
504 		entry->gpe_modified = 1;
505 	}
506 	g_part_new_provider(gp, table, entry);
507 
508 	/* Provide feedback if so requested. */
509 	if (gpp->gpp_parms & G_PART_PARM_OUTPUT) {
510 		sb = sbuf_new_auto();
511 		G_PART_FULLNAME(table, entry, sb, gp->name);
512 		sbuf_cat(sb, " added\n");
513 		sbuf_finish(sb);
514 		gctl_set_param(req, "output", sbuf_data(sb), sbuf_len(sb) + 1);
515 		sbuf_delete(sb);
516 	}
517 	return (0);
518 }
519 
520 static int
521 g_part_ctl_bootcode(struct gctl_req *req, struct g_part_parms *gpp)
522 {
523 	struct g_geom *gp;
524 	struct g_part_table *table;
525 	struct sbuf *sb;
526 	int error, sz;
527 
528 	gp = gpp->gpp_geom;
529 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, gp->name));
530 	g_topology_assert();
531 
532 	table = gp->softc;
533 	sz = table->gpt_scheme->gps_bootcodesz;
534 	if (sz == 0) {
535 		error = ENODEV;
536 		goto fail;
537 	}
538 	if (gpp->gpp_codesize > sz) {
539 		error = EFBIG;
540 		goto fail;
541 	}
542 
543 	error = G_PART_BOOTCODE(table, gpp);
544 	if (error)
545 		goto fail;
546 
547 	/* Provide feedback if so requested. */
548 	if (gpp->gpp_parms & G_PART_PARM_OUTPUT) {
549 		sb = sbuf_new_auto();
550 		sbuf_printf(sb, "%s has bootcode\n", gp->name);
551 		sbuf_finish(sb);
552 		gctl_set_param(req, "output", sbuf_data(sb), sbuf_len(sb) + 1);
553 		sbuf_delete(sb);
554 	}
555 	return (0);
556 
557  fail:
558 	gctl_error(req, "%d", error);
559 	return (error);
560 }
561 
562 static int
563 g_part_ctl_commit(struct gctl_req *req, struct g_part_parms *gpp)
564 {
565 	struct g_consumer *cp;
566 	struct g_geom *gp;
567 	struct g_provider *pp;
568 	struct g_part_entry *entry, *tmp;
569 	struct g_part_table *table;
570 	char *buf;
571 	int error, i;
572 
573 	gp = gpp->gpp_geom;
574 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, gp->name));
575 	g_topology_assert();
576 
577 	table = gp->softc;
578 	if (!table->gpt_opened) {
579 		gctl_error(req, "%d", EPERM);
580 		return (EPERM);
581 	}
582 
583 	g_topology_unlock();
584 
585 	cp = LIST_FIRST(&gp->consumer);
586 	if ((table->gpt_smhead | table->gpt_smtail) != 0) {
587 		pp = cp->provider;
588 		buf = g_malloc(pp->sectorsize, M_WAITOK | M_ZERO);
589 		while (table->gpt_smhead != 0) {
590 			i = ffs(table->gpt_smhead) - 1;
591 			error = g_write_data(cp, i * pp->sectorsize, buf,
592 			    pp->sectorsize);
593 			if (error) {
594 				g_free(buf);
595 				goto fail;
596 			}
597 			table->gpt_smhead &= ~(1 << i);
598 		}
599 		while (table->gpt_smtail != 0) {
600 			i = ffs(table->gpt_smtail) - 1;
601 			error = g_write_data(cp, pp->mediasize - (i + 1) *
602 			    pp->sectorsize, buf, pp->sectorsize);
603 			if (error) {
604 				g_free(buf);
605 				goto fail;
606 			}
607 			table->gpt_smtail &= ~(1 << i);
608 		}
609 		g_free(buf);
610 	}
611 
612 	if (table->gpt_scheme == &g_part_null_scheme) {
613 		g_topology_lock();
614 		g_access(cp, -1, -1, -1);
615 		g_part_wither(gp, ENXIO);
616 		return (0);
617 	}
618 
619 	error = G_PART_WRITE(table, cp);
620 	if (error)
621 		goto fail;
622 
623 	LIST_FOREACH_SAFE(entry, &table->gpt_entry, gpe_entry, tmp) {
624 		if (!entry->gpe_deleted) {
625 			entry->gpe_created = 0;
626 			entry->gpe_modified = 0;
627 			continue;
628 		}
629 		LIST_REMOVE(entry, gpe_entry);
630 		g_free(entry);
631 	}
632 	table->gpt_created = 0;
633 	table->gpt_opened = 0;
634 
635 	g_topology_lock();
636 	g_access(cp, -1, -1, -1);
637 	return (0);
638 
639 fail:
640 	g_topology_lock();
641 	gctl_error(req, "%d", error);
642 	return (error);
643 }
644 
645 static int
646 g_part_ctl_create(struct gctl_req *req, struct g_part_parms *gpp)
647 {
648 	struct g_consumer *cp;
649 	struct g_geom *gp;
650 	struct g_provider *pp;
651 	struct g_part_scheme *scheme;
652 	struct g_part_table *null, *table;
653 	struct sbuf *sb;
654 	int attr, error;
655 
656 	pp = gpp->gpp_provider;
657 	scheme = gpp->gpp_scheme;
658 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, pp->name));
659 	g_topology_assert();
660 
661 	/* Check that there isn't already a g_part geom on the provider. */
662 	error = g_part_parm_geom(pp->name, &gp);
663 	if (!error) {
664 		null = gp->softc;
665 		if (null->gpt_scheme != &g_part_null_scheme) {
666 			gctl_error(req, "%d geom '%s'", EEXIST, pp->name);
667 			return (EEXIST);
668 		}
669 	} else
670 		null = NULL;
671 
672 	if ((gpp->gpp_parms & G_PART_PARM_ENTRIES) &&
673 	    (gpp->gpp_entries < scheme->gps_minent ||
674 	     gpp->gpp_entries > scheme->gps_maxent)) {
675 		gctl_error(req, "%d entries '%d'", EINVAL, gpp->gpp_entries);
676 		return (EINVAL);
677 	}
678 
679 	if (null == NULL)
680 		gp = g_new_geomf(&g_part_class, "%s", pp->name);
681 	gp->softc = kobj_create((kobj_class_t)gpp->gpp_scheme, M_GEOM,
682 	    M_WAITOK);
683 	table = gp->softc;
684 	table->gpt_gp = gp;
685 	table->gpt_scheme = gpp->gpp_scheme;
686 	table->gpt_entries = (gpp->gpp_parms & G_PART_PARM_ENTRIES) ?
687 	    gpp->gpp_entries : scheme->gps_minent;
688 	LIST_INIT(&table->gpt_entry);
689 	if (null == NULL) {
690 		cp = g_new_consumer(gp);
691 		error = g_attach(cp, pp);
692 		if (error == 0)
693 			error = g_access(cp, 1, 1, 1);
694 		if (error != 0) {
695 			g_part_wither(gp, error);
696 			gctl_error(req, "%d geom '%s'", error, pp->name);
697 			return (error);
698 		}
699 		table->gpt_opened = 1;
700 	} else {
701 		cp = LIST_FIRST(&gp->consumer);
702 		table->gpt_opened = null->gpt_opened;
703 		table->gpt_smhead = null->gpt_smhead;
704 		table->gpt_smtail = null->gpt_smtail;
705 	}
706 
707 	g_topology_unlock();
708 
709 	/* Make sure the provider has media. */
710 	if (pp->mediasize == 0 || pp->sectorsize == 0) {
711 		error = ENODEV;
712 		goto fail;
713 	}
714 
715 	/* Make sure we can nest and if so, determine our depth. */
716 	error = g_getattr("PART::isleaf", cp, &attr);
717 	if (!error && attr) {
718 		error = ENODEV;
719 		goto fail;
720 	}
721 	error = g_getattr("PART::depth", cp, &attr);
722 	table->gpt_depth = (!error) ? attr + 1 : 0;
723 
724 	/*
725 	 * Synthesize a disk geometry. Some partitioning schemes
726 	 * depend on it and since some file systems need it even
727 	 * when the partitition scheme doesn't, we do it here in
728 	 * scheme-independent code.
729 	 */
730 	g_part_geometry(table, cp, pp->mediasize / pp->sectorsize);
731 
732 	error = G_PART_CREATE(table, gpp);
733 	if (error)
734 		goto fail;
735 
736 	g_topology_lock();
737 
738 	table->gpt_created = 1;
739 	if (null != NULL)
740 		kobj_delete((kobj_t)null, M_GEOM);
741 
742 	/*
743 	 * Support automatic commit by filling in the gpp_geom
744 	 * parameter.
745 	 */
746 	gpp->gpp_parms |= G_PART_PARM_GEOM;
747 	gpp->gpp_geom = gp;
748 
749 	/* Provide feedback if so requested. */
750 	if (gpp->gpp_parms & G_PART_PARM_OUTPUT) {
751 		sb = sbuf_new_auto();
752 		sbuf_printf(sb, "%s created\n", gp->name);
753 		sbuf_finish(sb);
754 		gctl_set_param(req, "output", sbuf_data(sb), sbuf_len(sb) + 1);
755 		sbuf_delete(sb);
756 	}
757 	return (0);
758 
759 fail:
760 	g_topology_lock();
761 	if (null == NULL) {
762 		g_access(cp, -1, -1, -1);
763 		g_part_wither(gp, error);
764 	} else {
765 		kobj_delete((kobj_t)gp->softc, M_GEOM);
766 		gp->softc = null;
767 	}
768 	gctl_error(req, "%d provider", error);
769 	return (error);
770 }
771 
772 static int
773 g_part_ctl_delete(struct gctl_req *req, struct g_part_parms *gpp)
774 {
775 	struct g_geom *gp;
776 	struct g_provider *pp;
777 	struct g_part_entry *entry;
778 	struct g_part_table *table;
779 	struct sbuf *sb;
780 
781 	gp = gpp->gpp_geom;
782 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, gp->name));
783 	g_topology_assert();
784 
785 	table = gp->softc;
786 
787 	LIST_FOREACH(entry, &table->gpt_entry, gpe_entry) {
788 		if (entry->gpe_deleted || entry->gpe_internal)
789 			continue;
790 		if (entry->gpe_index == gpp->gpp_index)
791 			break;
792 	}
793 	if (entry == NULL) {
794 		gctl_error(req, "%d index '%d'", ENOENT, gpp->gpp_index);
795 		return (ENOENT);
796 	}
797 
798 	pp = entry->gpe_pp;
799 	if (pp != NULL) {
800 		if (pp->acr > 0 || pp->acw > 0 || pp->ace > 0) {
801 			gctl_error(req, "%d", EBUSY);
802 			return (EBUSY);
803 		}
804 
805 		pp->private = NULL;
806 		entry->gpe_pp = NULL;
807 	}
808 
809 	if (entry->gpe_created) {
810 		LIST_REMOVE(entry, gpe_entry);
811 		g_free(entry);
812 	} else {
813 		entry->gpe_modified = 0;
814 		entry->gpe_deleted = 1;
815 	}
816 
817 	if (pp != NULL)
818 		g_wither_provider(pp, ENXIO);
819 
820 	/* Provide feedback if so requested. */
821 	if (gpp->gpp_parms & G_PART_PARM_OUTPUT) {
822 		sb = sbuf_new_auto();
823 		G_PART_FULLNAME(table, entry, sb, gp->name);
824 		sbuf_cat(sb, " deleted\n");
825 		sbuf_finish(sb);
826 		gctl_set_param(req, "output", sbuf_data(sb), sbuf_len(sb) + 1);
827 		sbuf_delete(sb);
828 	}
829 	return (0);
830 }
831 
832 static int
833 g_part_ctl_destroy(struct gctl_req *req, struct g_part_parms *gpp)
834 {
835 	struct g_geom *gp;
836 	struct g_part_entry *entry;
837 	struct g_part_table *null, *table;
838 	struct sbuf *sb;
839 	int error;
840 
841 	gp = gpp->gpp_geom;
842 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, gp->name));
843 	g_topology_assert();
844 
845 	table = gp->softc;
846 	LIST_FOREACH(entry, &table->gpt_entry, gpe_entry) {
847 		if (entry->gpe_deleted || entry->gpe_internal)
848 			continue;
849 		gctl_error(req, "%d", EBUSY);
850 		return (EBUSY);
851 	}
852 
853 	error = G_PART_DESTROY(table, gpp);
854 	if (error) {
855 		gctl_error(req, "%d", error);
856 		return (error);
857 	}
858 
859 	gp->softc = kobj_create((kobj_class_t)&g_part_null_scheme, M_GEOM,
860 	    M_WAITOK);
861 	null = gp->softc;
862 	null->gpt_gp = gp;
863 	null->gpt_scheme = &g_part_null_scheme;
864 	LIST_INIT(&null->gpt_entry);
865 	null->gpt_depth = table->gpt_depth;
866 	null->gpt_opened = table->gpt_opened;
867 	null->gpt_smhead = table->gpt_smhead;
868 	null->gpt_smtail = table->gpt_smtail;
869 
870 	while ((entry = LIST_FIRST(&table->gpt_entry)) != NULL) {
871 		LIST_REMOVE(entry, gpe_entry);
872 		g_free(entry);
873 	}
874 	kobj_delete((kobj_t)table, M_GEOM);
875 
876 	/* Provide feedback if so requested. */
877 	if (gpp->gpp_parms & G_PART_PARM_OUTPUT) {
878 		sb = sbuf_new_auto();
879 		sbuf_printf(sb, "%s destroyed\n", gp->name);
880 		sbuf_finish(sb);
881 		gctl_set_param(req, "output", sbuf_data(sb), sbuf_len(sb) + 1);
882 		sbuf_delete(sb);
883 	}
884 	return (0);
885 }
886 
887 static int
888 g_part_ctl_modify(struct gctl_req *req, struct g_part_parms *gpp)
889 {
890 	struct g_geom *gp;
891 	struct g_part_entry *entry;
892 	struct g_part_table *table;
893 	struct sbuf *sb;
894 	int error;
895 
896 	gp = gpp->gpp_geom;
897 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, gp->name));
898 	g_topology_assert();
899 
900 	table = gp->softc;
901 
902 	LIST_FOREACH(entry, &table->gpt_entry, gpe_entry) {
903 		if (entry->gpe_deleted || entry->gpe_internal)
904 			continue;
905 		if (entry->gpe_index == gpp->gpp_index)
906 			break;
907 	}
908 	if (entry == NULL) {
909 		gctl_error(req, "%d index '%d'", ENOENT, gpp->gpp_index);
910 		return (ENOENT);
911 	}
912 
913 	error = G_PART_MODIFY(table, entry, gpp);
914 	if (error) {
915 		gctl_error(req, "%d", error);
916 		return (error);
917 	}
918 
919 	if (!entry->gpe_created)
920 		entry->gpe_modified = 1;
921 
922 	/* Provide feedback if so requested. */
923 	if (gpp->gpp_parms & G_PART_PARM_OUTPUT) {
924 		sb = sbuf_new_auto();
925 		G_PART_FULLNAME(table, entry, sb, gp->name);
926 		sbuf_cat(sb, " modified\n");
927 		sbuf_finish(sb);
928 		gctl_set_param(req, "output", sbuf_data(sb), sbuf_len(sb) + 1);
929 		sbuf_delete(sb);
930 	}
931 	return (0);
932 }
933 
934 static int
935 g_part_ctl_move(struct gctl_req *req, struct g_part_parms *gpp)
936 {
937 	gctl_error(req, "%d verb 'move'", ENOSYS);
938 	return (ENOSYS);
939 }
940 
941 static int
942 g_part_ctl_recover(struct gctl_req *req, struct g_part_parms *gpp)
943 {
944 	gctl_error(req, "%d verb 'recover'", ENOSYS);
945 	return (ENOSYS);
946 }
947 
948 static int
949 g_part_ctl_resize(struct gctl_req *req, struct g_part_parms *gpp)
950 {
951 	gctl_error(req, "%d verb 'resize'", ENOSYS);
952 	return (ENOSYS);
953 }
954 
955 static int
956 g_part_ctl_setunset(struct gctl_req *req, struct g_part_parms *gpp,
957     unsigned int set)
958 {
959 	struct g_geom *gp;
960 	struct g_part_entry *entry;
961 	struct g_part_table *table;
962 	struct sbuf *sb;
963 	int error;
964 
965 	gp = gpp->gpp_geom;
966 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, gp->name));
967 	g_topology_assert();
968 
969 	table = gp->softc;
970 
971 	LIST_FOREACH(entry, &table->gpt_entry, gpe_entry) {
972 		if (entry->gpe_deleted || entry->gpe_internal)
973 			continue;
974 		if (entry->gpe_index == gpp->gpp_index)
975 			break;
976 	}
977 	if (entry == NULL) {
978 		gctl_error(req, "%d index '%d'", ENOENT, gpp->gpp_index);
979 		return (ENOENT);
980 	}
981 
982 	error = G_PART_SETUNSET(table, entry, gpp->gpp_attrib, set);
983 	if (error) {
984 		gctl_error(req, "%d attrib '%s'", error, gpp->gpp_attrib);
985 		return (error);
986 	}
987 
988 	/* Provide feedback if so requested. */
989 	if (gpp->gpp_parms & G_PART_PARM_OUTPUT) {
990 		sb = sbuf_new_auto();
991 		G_PART_FULLNAME(table, entry, sb, gp->name);
992 		sbuf_printf(sb, " has %s %sset\n", gpp->gpp_attrib,
993 		    (set) ? "" : "un");
994 		sbuf_finish(sb);
995 		gctl_set_param(req, "output", sbuf_data(sb), sbuf_len(sb) + 1);
996 		sbuf_delete(sb);
997 	}
998 	return (0);
999 }
1000 
1001 static int
1002 g_part_ctl_undo(struct gctl_req *req, struct g_part_parms *gpp)
1003 {
1004 	struct g_consumer *cp;
1005 	struct g_provider *pp;
1006 	struct g_geom *gp;
1007 	struct g_part_entry *entry, *tmp;
1008 	struct g_part_table *table;
1009 	int error, reprobe;
1010 
1011 	gp = gpp->gpp_geom;
1012 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, gp->name));
1013 	g_topology_assert();
1014 
1015 	table = gp->softc;
1016 	if (!table->gpt_opened) {
1017 		gctl_error(req, "%d", EPERM);
1018 		return (EPERM);
1019 	}
1020 
1021 	cp = LIST_FIRST(&gp->consumer);
1022 	LIST_FOREACH_SAFE(entry, &table->gpt_entry, gpe_entry, tmp) {
1023 		entry->gpe_modified = 0;
1024 		if (entry->gpe_created) {
1025 			pp = entry->gpe_pp;
1026 			if (pp != NULL) {
1027 				pp->private = NULL;
1028 				entry->gpe_pp = NULL;
1029 				g_wither_provider(pp, ENXIO);
1030 			}
1031 			entry->gpe_deleted = 1;
1032 		}
1033 		if (entry->gpe_deleted) {
1034 			LIST_REMOVE(entry, gpe_entry);
1035 			g_free(entry);
1036 		}
1037 	}
1038 
1039 	g_topology_unlock();
1040 
1041 	reprobe = (table->gpt_scheme == &g_part_null_scheme ||
1042 	    table->gpt_created) ? 1 : 0;
1043 
1044 	if (reprobe) {
1045 		if (!LIST_EMPTY(&table->gpt_entry)) {
1046 			error = EBUSY;
1047 			goto fail;
1048 		}
1049 		error = g_part_probe(gp, cp, table->gpt_depth);
1050 		if (error) {
1051 			g_topology_lock();
1052 			g_access(cp, -1, -1, -1);
1053 			g_part_wither(gp, error);
1054 			return (0);
1055 		}
1056 		table = gp->softc;
1057 	}
1058 
1059 	error = G_PART_READ(table, cp);
1060 	if (error)
1061 		goto fail;
1062 
1063 	g_topology_lock();
1064 
1065 	LIST_FOREACH(entry, &table->gpt_entry, gpe_entry) {
1066 		if (!entry->gpe_internal)
1067 			g_part_new_provider(gp, table, entry);
1068 	}
1069 
1070 	table->gpt_opened = 0;
1071 	g_access(cp, -1, -1, -1);
1072 	return (0);
1073 
1074 fail:
1075 	g_topology_lock();
1076 	gctl_error(req, "%d", error);
1077 	return (error);
1078 }
1079 
1080 static void
1081 g_part_wither(struct g_geom *gp, int error)
1082 {
1083 	struct g_part_entry *entry;
1084 	struct g_part_table *table;
1085 
1086 	table = gp->softc;
1087 	if (table != NULL) {
1088 		while ((entry = LIST_FIRST(&table->gpt_entry)) != NULL) {
1089 			LIST_REMOVE(entry, gpe_entry);
1090 			g_free(entry);
1091 		}
1092 		if (gp->softc != NULL) {
1093 			kobj_delete((kobj_t)gp->softc, M_GEOM);
1094 			gp->softc = NULL;
1095 		}
1096 	}
1097 	g_wither_geom(gp, error);
1098 }
1099 
1100 /*
1101  * Class methods.
1102  */
1103 
1104 static void
1105 g_part_ctlreq(struct gctl_req *req, struct g_class *mp, const char *verb)
1106 {
1107 	struct g_part_parms gpp;
1108 	struct g_part_table *table;
1109 	struct gctl_req_arg *ap;
1110 	const char *p;
1111 	enum g_part_ctl ctlreq;
1112 	unsigned int i, mparms, oparms, parm;
1113 	int auto_commit, close_on_error;
1114 	int error, len, modifies;
1115 
1116 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s,%s)", __func__, mp->name, verb));
1117 	g_topology_assert();
1118 
1119 	ctlreq = G_PART_CTL_NONE;
1120 	modifies = 1;
1121 	mparms = 0;
1122 	oparms = G_PART_PARM_FLAGS | G_PART_PARM_OUTPUT | G_PART_PARM_VERSION;
1123 	switch (*verb) {
1124 	case 'a':
1125 		if (!strcmp(verb, "add")) {
1126 			ctlreq = G_PART_CTL_ADD;
1127 			mparms |= G_PART_PARM_GEOM | G_PART_PARM_SIZE |
1128 			    G_PART_PARM_START | G_PART_PARM_TYPE;
1129 			oparms |= G_PART_PARM_INDEX | G_PART_PARM_LABEL;
1130 		}
1131 		break;
1132 	case 'b':
1133 		if (!strcmp(verb, "bootcode")) {
1134 			ctlreq = G_PART_CTL_BOOTCODE;
1135 			mparms |= G_PART_PARM_GEOM | G_PART_PARM_BOOTCODE;
1136 		}
1137 		break;
1138 	case 'c':
1139 		if (!strcmp(verb, "commit")) {
1140 			ctlreq = G_PART_CTL_COMMIT;
1141 			mparms |= G_PART_PARM_GEOM;
1142 			modifies = 0;
1143 		} else if (!strcmp(verb, "create")) {
1144 			ctlreq = G_PART_CTL_CREATE;
1145 			mparms |= G_PART_PARM_PROVIDER | G_PART_PARM_SCHEME;
1146 			oparms |= G_PART_PARM_ENTRIES;
1147 		}
1148 		break;
1149 	case 'd':
1150 		if (!strcmp(verb, "delete")) {
1151 			ctlreq = G_PART_CTL_DELETE;
1152 			mparms |= G_PART_PARM_GEOM | G_PART_PARM_INDEX;
1153 		} else if (!strcmp(verb, "destroy")) {
1154 			ctlreq = G_PART_CTL_DESTROY;
1155 			mparms |= G_PART_PARM_GEOM;
1156 		}
1157 		break;
1158 	case 'm':
1159 		if (!strcmp(verb, "modify")) {
1160 			ctlreq = G_PART_CTL_MODIFY;
1161 			mparms |= G_PART_PARM_GEOM | G_PART_PARM_INDEX;
1162 			oparms |= G_PART_PARM_LABEL | G_PART_PARM_TYPE;
1163 		} else if (!strcmp(verb, "move")) {
1164 			ctlreq = G_PART_CTL_MOVE;
1165 			mparms |= G_PART_PARM_GEOM | G_PART_PARM_INDEX;
1166 		}
1167 		break;
1168 	case 'r':
1169 		if (!strcmp(verb, "recover")) {
1170 			ctlreq = G_PART_CTL_RECOVER;
1171 			mparms |= G_PART_PARM_GEOM;
1172 		} else if (!strcmp(verb, "resize")) {
1173 			ctlreq = G_PART_CTL_RESIZE;
1174 			mparms |= G_PART_PARM_GEOM | G_PART_PARM_INDEX;
1175 		}
1176 		break;
1177 	case 's':
1178 		if (!strcmp(verb, "set")) {
1179 			ctlreq = G_PART_CTL_SET;
1180 			mparms |= G_PART_PARM_ATTRIB | G_PART_PARM_GEOM |
1181 			    G_PART_PARM_INDEX;
1182 		}
1183 		break;
1184 	case 'u':
1185 		if (!strcmp(verb, "undo")) {
1186 			ctlreq = G_PART_CTL_UNDO;
1187 			mparms |= G_PART_PARM_GEOM;
1188 			modifies = 0;
1189 		} else if (!strcmp(verb, "unset")) {
1190 			ctlreq = G_PART_CTL_UNSET;
1191 			mparms |= G_PART_PARM_ATTRIB | G_PART_PARM_GEOM |
1192 			    G_PART_PARM_INDEX;
1193 		}
1194 		break;
1195 	}
1196 	if (ctlreq == G_PART_CTL_NONE) {
1197 		gctl_error(req, "%d verb '%s'", EINVAL, verb);
1198 		return;
1199 	}
1200 
1201 	bzero(&gpp, sizeof(gpp));
1202 	for (i = 0; i < req->narg; i++) {
1203 		ap = &req->arg[i];
1204 		parm = 0;
1205 		switch (ap->name[0]) {
1206 		case 'a':
1207 			if (!strcmp(ap->name, "attrib"))
1208 				parm = G_PART_PARM_ATTRIB;
1209 			break;
1210 		case 'b':
1211 			if (!strcmp(ap->name, "bootcode"))
1212 				parm = G_PART_PARM_BOOTCODE;
1213 			break;
1214 		case 'c':
1215 			if (!strcmp(ap->name, "class"))
1216 				continue;
1217 			break;
1218 		case 'e':
1219 			if (!strcmp(ap->name, "entries"))
1220 				parm = G_PART_PARM_ENTRIES;
1221 			break;
1222 		case 'f':
1223 			if (!strcmp(ap->name, "flags"))
1224 				parm = G_PART_PARM_FLAGS;
1225 			break;
1226 		case 'g':
1227 			if (!strcmp(ap->name, "geom"))
1228 				parm = G_PART_PARM_GEOM;
1229 			break;
1230 		case 'i':
1231 			if (!strcmp(ap->name, "index"))
1232 				parm = G_PART_PARM_INDEX;
1233 			break;
1234 		case 'l':
1235 			if (!strcmp(ap->name, "label"))
1236 				parm = G_PART_PARM_LABEL;
1237 			break;
1238 		case 'o':
1239 			if (!strcmp(ap->name, "output"))
1240 				parm = G_PART_PARM_OUTPUT;
1241 			break;
1242 		case 'p':
1243 			if (!strcmp(ap->name, "provider"))
1244 				parm = G_PART_PARM_PROVIDER;
1245 			break;
1246 		case 's':
1247 			if (!strcmp(ap->name, "scheme"))
1248 				parm = G_PART_PARM_SCHEME;
1249 			else if (!strcmp(ap->name, "size"))
1250 				parm = G_PART_PARM_SIZE;
1251 			else if (!strcmp(ap->name, "start"))
1252 				parm = G_PART_PARM_START;
1253 			break;
1254 		case 't':
1255 			if (!strcmp(ap->name, "type"))
1256 				parm = G_PART_PARM_TYPE;
1257 			break;
1258 		case 'v':
1259 			if (!strcmp(ap->name, "verb"))
1260 				continue;
1261 			else if (!strcmp(ap->name, "version"))
1262 				parm = G_PART_PARM_VERSION;
1263 			break;
1264 		}
1265 		if ((parm & (mparms | oparms)) == 0) {
1266 			gctl_error(req, "%d param '%s'", EINVAL, ap->name);
1267 			return;
1268 		}
1269 		if (parm == G_PART_PARM_BOOTCODE)
1270 			p = gctl_get_param(req, ap->name, &len);
1271 		else
1272 			p = gctl_get_asciiparam(req, ap->name);
1273 		if (p == NULL) {
1274 			gctl_error(req, "%d param '%s'", ENOATTR, ap->name);
1275 			return;
1276 		}
1277 		switch (parm) {
1278 		case G_PART_PARM_ATTRIB:
1279 			error = g_part_parm_str(p, &gpp.gpp_attrib);
1280 			break;
1281 		case G_PART_PARM_BOOTCODE:
1282 			gpp.gpp_codeptr = p;
1283 			gpp.gpp_codesize = len;
1284 			error = 0;
1285 			break;
1286 		case G_PART_PARM_ENTRIES:
1287 			error = g_part_parm_uint(p, &gpp.gpp_entries);
1288 			break;
1289 		case G_PART_PARM_FLAGS:
1290 			if (p[0] == '\0')
1291 				continue;
1292 			error = g_part_parm_str(p, &gpp.gpp_flags);
1293 			break;
1294 		case G_PART_PARM_GEOM:
1295 			error = g_part_parm_geom(p, &gpp.gpp_geom);
1296 			break;
1297 		case G_PART_PARM_INDEX:
1298 			error = g_part_parm_uint(p, &gpp.gpp_index);
1299 			break;
1300 		case G_PART_PARM_LABEL:
1301 			/* An empty label is always valid. */
1302 			gpp.gpp_label = p;
1303 			error = 0;
1304 			break;
1305 		case G_PART_PARM_OUTPUT:
1306 			error = 0;	/* Write-only parameter */
1307 			break;
1308 		case G_PART_PARM_PROVIDER:
1309 			error = g_part_parm_provider(p, &gpp.gpp_provider);
1310 			break;
1311 		case G_PART_PARM_SCHEME:
1312 			error = g_part_parm_scheme(p, &gpp.gpp_scheme);
1313 			break;
1314 		case G_PART_PARM_SIZE:
1315 			error = g_part_parm_quad(p, &gpp.gpp_size);
1316 			break;
1317 		case G_PART_PARM_START:
1318 			error = g_part_parm_quad(p, &gpp.gpp_start);
1319 			break;
1320 		case G_PART_PARM_TYPE:
1321 			error = g_part_parm_str(p, &gpp.gpp_type);
1322 			break;
1323 		case G_PART_PARM_VERSION:
1324 			error = g_part_parm_uint(p, &gpp.gpp_version);
1325 			break;
1326 		default:
1327 			error = EDOOFUS;
1328 			break;
1329 		}
1330 		if (error) {
1331 			gctl_error(req, "%d %s '%s'", error, ap->name, p);
1332 			return;
1333 		}
1334 		gpp.gpp_parms |= parm;
1335 	}
1336 	if ((gpp.gpp_parms & mparms) != mparms) {
1337 		parm = mparms - (gpp.gpp_parms & mparms);
1338 		gctl_error(req, "%d param '%x'", ENOATTR, parm);
1339 		return;
1340 	}
1341 
1342 	/* Obtain permissions if possible/necessary. */
1343 	close_on_error = 0;
1344 	table = NULL;
1345 	if (modifies && (gpp.gpp_parms & G_PART_PARM_GEOM)) {
1346 		table = gpp.gpp_geom->softc;
1347 		if (table != NULL && !table->gpt_opened) {
1348 			error = g_access(LIST_FIRST(&gpp.gpp_geom->consumer),
1349 			    1, 1, 1);
1350 			if (error) {
1351 				gctl_error(req, "%d geom '%s'", error,
1352 				    gpp.gpp_geom->name);
1353 				return;
1354 			}
1355 			table->gpt_opened = 1;
1356 			close_on_error = 1;
1357 		}
1358 	}
1359 
1360 	/* Allow the scheme to check or modify the parameters. */
1361 	if (table != NULL) {
1362 		error = G_PART_PRECHECK(table, ctlreq, &gpp);
1363 		if (error) {
1364 			gctl_error(req, "%d pre-check failed", error);
1365 			goto out;
1366 		}
1367 	} else
1368 		error = EDOOFUS;	/* Prevent bogus uninit. warning. */
1369 
1370 	switch (ctlreq) {
1371 	case G_PART_CTL_NONE:
1372 		panic("%s", __func__);
1373 	case G_PART_CTL_ADD:
1374 		error = g_part_ctl_add(req, &gpp);
1375 		break;
1376 	case G_PART_CTL_BOOTCODE:
1377 		error = g_part_ctl_bootcode(req, &gpp);
1378 		break;
1379 	case G_PART_CTL_COMMIT:
1380 		error = g_part_ctl_commit(req, &gpp);
1381 		break;
1382 	case G_PART_CTL_CREATE:
1383 		error = g_part_ctl_create(req, &gpp);
1384 		break;
1385 	case G_PART_CTL_DELETE:
1386 		error = g_part_ctl_delete(req, &gpp);
1387 		break;
1388 	case G_PART_CTL_DESTROY:
1389 		error = g_part_ctl_destroy(req, &gpp);
1390 		break;
1391 	case G_PART_CTL_MODIFY:
1392 		error = g_part_ctl_modify(req, &gpp);
1393 		break;
1394 	case G_PART_CTL_MOVE:
1395 		error = g_part_ctl_move(req, &gpp);
1396 		break;
1397 	case G_PART_CTL_RECOVER:
1398 		error = g_part_ctl_recover(req, &gpp);
1399 		break;
1400 	case G_PART_CTL_RESIZE:
1401 		error = g_part_ctl_resize(req, &gpp);
1402 		break;
1403 	case G_PART_CTL_SET:
1404 		error = g_part_ctl_setunset(req, &gpp, 1);
1405 		break;
1406 	case G_PART_CTL_UNDO:
1407 		error = g_part_ctl_undo(req, &gpp);
1408 		break;
1409 	case G_PART_CTL_UNSET:
1410 		error = g_part_ctl_setunset(req, &gpp, 0);
1411 		break;
1412 	}
1413 
1414 	/* Implement automatic commit. */
1415 	if (!error) {
1416 		auto_commit = (modifies &&
1417 		    (gpp.gpp_parms & G_PART_PARM_FLAGS) &&
1418 		    strchr(gpp.gpp_flags, 'C') != NULL) ? 1 : 0;
1419 		if (auto_commit) {
1420 			KASSERT(gpp.gpp_parms & G_PART_PARM_GEOM, (__func__));
1421 			error = g_part_ctl_commit(req, &gpp);
1422 		}
1423 	}
1424 
1425  out:
1426 	if (error && close_on_error) {
1427 		g_access(LIST_FIRST(&gpp.gpp_geom->consumer), -1, -1, -1);
1428 		table->gpt_opened = 0;
1429 	}
1430 }
1431 
1432 static int
1433 g_part_destroy_geom(struct gctl_req *req, struct g_class *mp,
1434     struct g_geom *gp)
1435 {
1436 
1437 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s,%s)", __func__, mp->name, gp->name));
1438 	g_topology_assert();
1439 
1440 	g_part_wither(gp, EINVAL);
1441 	return (0);
1442 }
1443 
1444 static struct g_geom *
1445 g_part_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
1446 {
1447 	struct g_consumer *cp;
1448 	struct g_geom *gp;
1449 	struct g_part_entry *entry;
1450 	struct g_part_table *table;
1451 	struct root_hold_token *rht;
1452 	int attr, depth;
1453 	int error;
1454 
1455 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s,%s)", __func__, mp->name, pp->name));
1456 	g_topology_assert();
1457 
1458 	/*
1459 	 * Create a GEOM with consumer and hook it up to the provider.
1460 	 * With that we become part of the topology. Optain read access
1461 	 * to the provider.
1462 	 */
1463 	gp = g_new_geomf(mp, "%s", pp->name);
1464 	cp = g_new_consumer(gp);
1465 	error = g_attach(cp, pp);
1466 	if (error == 0)
1467 		error = g_access(cp, 1, 0, 0);
1468 	if (error != 0) {
1469 		g_part_wither(gp, error);
1470 		return (NULL);
1471 	}
1472 
1473 	rht = root_mount_hold(mp->name);
1474 	g_topology_unlock();
1475 
1476 	/*
1477 	 * Short-circuit the whole probing galore when there's no
1478 	 * media present.
1479 	 */
1480 	if (pp->mediasize == 0 || pp->sectorsize == 0) {
1481 		error = ENODEV;
1482 		goto fail;
1483 	}
1484 
1485 	/* Make sure we can nest and if so, determine our depth. */
1486 	error = g_getattr("PART::isleaf", cp, &attr);
1487 	if (!error && attr) {
1488 		error = ENODEV;
1489 		goto fail;
1490 	}
1491 	error = g_getattr("PART::depth", cp, &attr);
1492 	depth = (!error) ? attr + 1 : 0;
1493 
1494 	error = g_part_probe(gp, cp, depth);
1495 	if (error)
1496 		goto fail;
1497 
1498 	table = gp->softc;
1499 
1500 	/*
1501 	 * Synthesize a disk geometry. Some partitioning schemes
1502 	 * depend on it and since some file systems need it even
1503 	 * when the partitition scheme doesn't, we do it here in
1504 	 * scheme-independent code.
1505 	 */
1506 	g_part_geometry(table, cp, pp->mediasize / pp->sectorsize);
1507 
1508 	error = G_PART_READ(table, cp);
1509 	if (error)
1510 		goto fail;
1511 
1512 	g_topology_lock();
1513 	LIST_FOREACH(entry, &table->gpt_entry, gpe_entry) {
1514 		if (!entry->gpe_internal)
1515 			g_part_new_provider(gp, table, entry);
1516 	}
1517 
1518 	root_mount_rel(rht);
1519 	g_access(cp, -1, 0, 0);
1520 	return (gp);
1521 
1522  fail:
1523 	g_topology_lock();
1524 	root_mount_rel(rht);
1525 	g_access(cp, -1, 0, 0);
1526 	g_part_wither(gp, error);
1527 	return (NULL);
1528 }
1529 
1530 /*
1531  * Geom methods.
1532  */
1533 
1534 static int
1535 g_part_access(struct g_provider *pp, int dr, int dw, int de)
1536 {
1537 	struct g_consumer *cp;
1538 
1539 	G_PART_TRACE((G_T_ACCESS, "%s(%s,%d,%d,%d)", __func__, pp->name, dr,
1540 	    dw, de));
1541 
1542 	cp = LIST_FIRST(&pp->geom->consumer);
1543 
1544 	/* We always gain write-exclusive access. */
1545 	return (g_access(cp, dr, dw, dw + de));
1546 }
1547 
1548 static void
1549 g_part_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1550     struct g_consumer *cp, struct g_provider *pp)
1551 {
1552 	char buf[64];
1553 	struct g_part_entry *entry;
1554 	struct g_part_table *table;
1555 
1556 	KASSERT(sb != NULL && gp != NULL, (__func__));
1557 	table = gp->softc;
1558 
1559 	if (indent == NULL) {
1560 		KASSERT(cp == NULL && pp != NULL, (__func__));
1561 		entry = pp->private;
1562 		if (entry == NULL)
1563 			return;
1564 		sbuf_printf(sb, " i %u o %ju ty %s", entry->gpe_index,
1565 		    (uintmax_t)entry->gpe_offset,
1566 		    G_PART_TYPE(table, entry, buf, sizeof(buf)));
1567 		/*
1568 		 * libdisk compatibility quirk - the scheme dumps the
1569 		 * slicer name and partition type in a way that is
1570 		 * compatible with libdisk. When libdisk is not used
1571 		 * anymore, this should go away.
1572 		 */
1573 		G_PART_DUMPCONF(table, entry, sb, indent);
1574 	} else if (cp != NULL) {	/* Consumer configuration. */
1575 		KASSERT(pp == NULL, (__func__));
1576 		/* none */
1577 	} else if (pp != NULL) {	/* Provider configuration. */
1578 		entry = pp->private;
1579 		if (entry == NULL)
1580 			return;
1581 		sbuf_printf(sb, "%s<start>%ju</start>\n", indent,
1582 		    (uintmax_t)entry->gpe_start);
1583 		sbuf_printf(sb, "%s<end>%ju</end>\n", indent,
1584 		    (uintmax_t)entry->gpe_end);
1585 		sbuf_printf(sb, "%s<index>%u</index>\n", indent,
1586 		    entry->gpe_index);
1587 		sbuf_printf(sb, "%s<type>%s</type>\n", indent,
1588 		    G_PART_TYPE(table, entry, buf, sizeof(buf)));
1589 		sbuf_printf(sb, "%s<offset>%ju</offset>\n", indent,
1590 		    (uintmax_t)entry->gpe_offset);
1591 		sbuf_printf(sb, "%s<length>%ju</length>\n", indent,
1592 		    (uintmax_t)pp->mediasize);
1593 		G_PART_DUMPCONF(table, entry, sb, indent);
1594 	} else {			/* Geom configuration. */
1595 		sbuf_printf(sb, "%s<scheme>%s</scheme>\n", indent,
1596 		    table->gpt_scheme->name);
1597 		sbuf_printf(sb, "%s<entries>%u</entries>\n", indent,
1598 		    table->gpt_entries);
1599 		sbuf_printf(sb, "%s<first>%ju</first>\n", indent,
1600 		    (uintmax_t)table->gpt_first);
1601 		sbuf_printf(sb, "%s<last>%ju</last>\n", indent,
1602 		    (uintmax_t)table->gpt_last);
1603 		sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n", indent,
1604 		    table->gpt_sectors);
1605 		sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n", indent,
1606 		    table->gpt_heads);
1607 		G_PART_DUMPCONF(table, NULL, sb, indent);
1608 	}
1609 }
1610 
1611 static void
1612 g_part_orphan(struct g_consumer *cp)
1613 {
1614 	struct g_provider *pp;
1615 
1616 	pp = cp->provider;
1617 	KASSERT(pp != NULL, (__func__));
1618 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, pp->name));
1619 	g_topology_assert();
1620 
1621 	KASSERT(pp->error != 0, (__func__));
1622 	g_part_wither(cp->geom, pp->error);
1623 }
1624 
1625 static void
1626 g_part_spoiled(struct g_consumer *cp)
1627 {
1628 
1629 	G_PART_TRACE((G_T_TOPOLOGY, "%s(%s)", __func__, cp->provider->name));
1630 	g_topology_assert();
1631 
1632 	g_part_wither(cp->geom, ENXIO);
1633 }
1634 
1635 static void
1636 g_part_start(struct bio *bp)
1637 {
1638 	struct bio *bp2;
1639 	struct g_consumer *cp;
1640 	struct g_geom *gp;
1641 	struct g_part_entry *entry;
1642 	struct g_part_table *table;
1643 	struct g_kerneldump *gkd;
1644 	struct g_provider *pp;
1645 
1646 	pp = bp->bio_to;
1647 	gp = pp->geom;
1648 	table = gp->softc;
1649 	cp = LIST_FIRST(&gp->consumer);
1650 
1651 	G_PART_TRACE((G_T_BIO, "%s: cmd=%d, provider=%s", __func__, bp->bio_cmd,
1652 	    pp->name));
1653 
1654 	entry = pp->private;
1655 	if (entry == NULL) {
1656 		g_io_deliver(bp, ENXIO);
1657 		return;
1658 	}
1659 
1660 	switch(bp->bio_cmd) {
1661 	case BIO_DELETE:
1662 	case BIO_READ:
1663 	case BIO_WRITE:
1664 		if (bp->bio_offset >= pp->mediasize) {
1665 			g_io_deliver(bp, EIO);
1666 			return;
1667 		}
1668 		bp2 = g_clone_bio(bp);
1669 		if (bp2 == NULL) {
1670 			g_io_deliver(bp, ENOMEM);
1671 			return;
1672 		}
1673 		if (bp2->bio_offset + bp2->bio_length > pp->mediasize)
1674 			bp2->bio_length = pp->mediasize - bp2->bio_offset;
1675 		bp2->bio_done = g_std_done;
1676 		bp2->bio_offset += entry->gpe_offset;
1677 		g_io_request(bp2, cp);
1678 		return;
1679 	case BIO_FLUSH:
1680 		break;
1681 	case BIO_GETATTR:
1682 		if (g_handleattr_int(bp, "GEOM::fwheads", table->gpt_heads))
1683 			return;
1684 		if (g_handleattr_int(bp, "GEOM::fwsectors", table->gpt_sectors))
1685 			return;
1686 		if (g_handleattr_int(bp, "PART::isleaf", table->gpt_isleaf))
1687 			return;
1688 		if (g_handleattr_int(bp, "PART::depth", table->gpt_depth))
1689 			return;
1690 		if (g_handleattr_str(bp, "PART::scheme",
1691 		    table->gpt_scheme->name))
1692 			return;
1693 		if (!strcmp("GEOM::kerneldump", bp->bio_attribute)) {
1694 			/*
1695 			 * Check that the partition is suitable for kernel
1696 			 * dumps. Typically only swap partitions should be
1697 			 * used.
1698 			 */
1699 			if (!G_PART_DUMPTO(table, entry)) {
1700 				g_io_deliver(bp, ENODEV);
1701 				printf("GEOM_PART: Partition '%s' not suitable"
1702 				    " for kernel dumps (wrong type?)\n",
1703 				    pp->name);
1704 				return;
1705 			}
1706 			gkd = (struct g_kerneldump *)bp->bio_data;
1707 			if (gkd->offset >= pp->mediasize) {
1708 				g_io_deliver(bp, EIO);
1709 				return;
1710 			}
1711 			if (gkd->offset + gkd->length > pp->mediasize)
1712 				gkd->length = pp->mediasize - gkd->offset;
1713 			gkd->offset += entry->gpe_offset;
1714 		}
1715 		break;
1716 	default:
1717 		g_io_deliver(bp, EOPNOTSUPP);
1718 		return;
1719 	}
1720 
1721 	bp2 = g_clone_bio(bp);
1722 	if (bp2 == NULL) {
1723 		g_io_deliver(bp, ENOMEM);
1724 		return;
1725 	}
1726 	bp2->bio_done = g_std_done;
1727 	g_io_request(bp2, cp);
1728 }
1729 
1730 static void
1731 g_part_init(struct g_class *mp)
1732 {
1733 
1734 	TAILQ_INSERT_HEAD(&g_part_schemes, &g_part_null_scheme, scheme_list);
1735 }
1736 
1737 static void
1738 g_part_fini(struct g_class *mp)
1739 {
1740 
1741 	TAILQ_REMOVE(&g_part_schemes, &g_part_null_scheme, scheme_list);
1742 }
1743 
1744 static void
1745 g_part_unload_event(void *arg, int flag)
1746 {
1747 	struct g_consumer *cp;
1748 	struct g_geom *gp;
1749 	struct g_provider *pp;
1750 	struct g_part_scheme *scheme;
1751 	struct g_part_table *table;
1752 	uintptr_t *xchg;
1753 	int acc, error;
1754 
1755 	if (flag == EV_CANCEL)
1756 		return;
1757 
1758 	xchg = arg;
1759 	error = 0;
1760 	scheme = (void *)(*xchg);
1761 
1762 	g_topology_assert();
1763 
1764 	LIST_FOREACH(gp, &g_part_class.geom, geom) {
1765 		table = gp->softc;
1766 		if (table->gpt_scheme != scheme)
1767 			continue;
1768 
1769 		acc = 0;
1770 		LIST_FOREACH(pp, &gp->provider, provider)
1771 			acc += pp->acr + pp->acw + pp->ace;
1772 		LIST_FOREACH(cp, &gp->consumer, consumer)
1773 			acc += cp->acr + cp->acw + cp->ace;
1774 
1775 		if (!acc)
1776 			g_part_wither(gp, ENOSYS);
1777 		else
1778 			error = EBUSY;
1779 	}
1780 
1781 	if (!error)
1782 		TAILQ_REMOVE(&g_part_schemes, scheme, scheme_list);
1783 
1784 	*xchg = error;
1785 }
1786 
1787 int
1788 g_part_modevent(module_t mod, int type, struct g_part_scheme *scheme)
1789 {
1790 	uintptr_t arg;
1791 	int error;
1792 
1793 	switch (type) {
1794 	case MOD_LOAD:
1795 		TAILQ_INSERT_TAIL(&g_part_schemes, scheme, scheme_list);
1796 
1797 		error = g_retaste(&g_part_class);
1798 		if (error)
1799 			TAILQ_REMOVE(&g_part_schemes, scheme, scheme_list);
1800 		break;
1801 	case MOD_UNLOAD:
1802 		arg = (uintptr_t)scheme;
1803 		error = g_waitfor_event(g_part_unload_event, &arg, M_WAITOK,
1804 		    NULL);
1805 		if (!error)
1806 			error = (arg == (uintptr_t)scheme) ? EDOOFUS : arg;
1807 		break;
1808 	default:
1809 		error = EOPNOTSUPP;
1810 		break;
1811 	}
1812 
1813 	return (error);
1814 }
1815