xref: /freebsd/sys/geom/shsec/g_shsec.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
1 /*-
2  * Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
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  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/module.h>
34 #include <sys/lock.h>
35 #include <sys/mutex.h>
36 #include <sys/bio.h>
37 #include <sys/sysctl.h>
38 #include <sys/malloc.h>
39 #include <vm/uma.h>
40 #include <geom/geom.h>
41 #include <geom/shsec/g_shsec.h>
42 
43 
44 static MALLOC_DEFINE(M_SHSEC, "shsec_data", "GEOM_SHSEC Data");
45 
46 static uma_zone_t g_shsec_zone;
47 
48 static int g_shsec_destroy(struct g_shsec_softc *sc, boolean_t force);
49 static int g_shsec_destroy_geom(struct gctl_req *req, struct g_class *mp,
50     struct g_geom *gp);
51 
52 static g_taste_t g_shsec_taste;
53 static g_ctl_req_t g_shsec_config;
54 static g_dumpconf_t g_shsec_dumpconf;
55 static g_init_t g_shsec_init;
56 static g_fini_t g_shsec_fini;
57 
58 struct g_class g_shsec_class = {
59 	.name = G_SHSEC_CLASS_NAME,
60 	.version = G_VERSION,
61 	.ctlreq = g_shsec_config,
62 	.taste = g_shsec_taste,
63 	.destroy_geom = g_shsec_destroy_geom,
64 	.init = g_shsec_init,
65 	.fini = g_shsec_fini
66 };
67 
68 SYSCTL_DECL(_kern_geom);
69 SYSCTL_NODE(_kern_geom, OID_AUTO, shsec, CTLFLAG_RW, 0, "GEOM_SHSEC stuff");
70 static u_int g_shsec_debug = 0;
71 TUNABLE_INT("kern.geom.shsec.debug", &g_shsec_debug);
72 SYSCTL_UINT(_kern_geom_shsec, OID_AUTO, debug, CTLFLAG_RW, &g_shsec_debug, 0,
73     "Debug level");
74 static u_int g_shsec_maxmem = MAXPHYS * 100;
75 TUNABLE_INT("kern.geom.shsec.maxmem", &g_shsec_maxmem);
76 SYSCTL_UINT(_kern_geom_shsec, OID_AUTO, maxmem, CTLFLAG_RD, &g_shsec_maxmem,
77     0, "Maximum memory that can be allocated for I/O (in bytes)");
78 static u_int g_shsec_alloc_failed = 0;
79 SYSCTL_UINT(_kern_geom_shsec, OID_AUTO, alloc_failed, CTLFLAG_RD,
80     &g_shsec_alloc_failed, 0, "How many times I/O allocation failed");
81 
82 /*
83  * Greatest Common Divisor.
84  */
85 static u_int
86 gcd(u_int a, u_int b)
87 {
88 	u_int c;
89 
90 	while (b != 0) {
91 		c = a;
92 		a = b;
93 		b = (c % b);
94 	}
95 	return (a);
96 }
97 
98 /*
99  * Least Common Multiple.
100  */
101 static u_int
102 lcm(u_int a, u_int b)
103 {
104 
105 	return ((a * b) / gcd(a, b));
106 }
107 
108 static void
109 g_shsec_init(struct g_class *mp __unused)
110 {
111 
112 	g_shsec_zone = uma_zcreate("g_shsec_zone", MAXPHYS, NULL, NULL, NULL,
113 	    NULL, 0, 0);
114 	g_shsec_maxmem -= g_shsec_maxmem % MAXPHYS;
115 	uma_zone_set_max(g_shsec_zone, g_shsec_maxmem / MAXPHYS);
116 }
117 
118 static void
119 g_shsec_fini(struct g_class *mp __unused)
120 {
121 
122 	uma_zdestroy(g_shsec_zone);
123 }
124 
125 /*
126  * Return the number of valid disks.
127  */
128 static u_int
129 g_shsec_nvalid(struct g_shsec_softc *sc)
130 {
131 	u_int i, no;
132 
133 	no = 0;
134 	for (i = 0; i < sc->sc_ndisks; i++) {
135 		if (sc->sc_disks[i] != NULL)
136 			no++;
137 	}
138 
139 	return (no);
140 }
141 
142 static void
143 g_shsec_remove_disk(struct g_consumer *cp)
144 {
145 	struct g_shsec_softc *sc;
146 	u_int no;
147 
148 	KASSERT(cp != NULL, ("Non-valid disk in %s.", __func__));
149 	sc = (struct g_shsec_softc *)cp->private;
150 	KASSERT(sc != NULL, ("NULL sc in %s.", __func__));
151 	no = cp->index;
152 
153 	G_SHSEC_DEBUG(0, "Disk %s removed from %s.", cp->provider->name,
154 	    sc->sc_name);
155 
156 	sc->sc_disks[no] = NULL;
157 	if (sc->sc_provider != NULL) {
158 		g_orphan_provider(sc->sc_provider, ENXIO);
159 		sc->sc_provider = NULL;
160 		G_SHSEC_DEBUG(0, "Device %s removed.", sc->sc_name);
161 	}
162 
163 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
164 		g_access(cp, -cp->acr, -cp->acw, -cp->ace);
165 	g_detach(cp);
166 	g_destroy_consumer(cp);
167 }
168 
169 static void
170 g_shsec_orphan(struct g_consumer *cp)
171 {
172 	struct g_shsec_softc *sc;
173 	struct g_geom *gp;
174 
175 	g_topology_assert();
176 	gp = cp->geom;
177 	sc = gp->softc;
178 	if (sc == NULL)
179 		return;
180 
181 	g_shsec_remove_disk(cp);
182 	/* If there are no valid disks anymore, remove device. */
183 	if (g_shsec_nvalid(sc) == 0)
184 		g_shsec_destroy(sc, 1);
185 }
186 
187 static int
188 g_shsec_access(struct g_provider *pp, int dr, int dw, int de)
189 {
190 	struct g_consumer *cp1, *cp2;
191 	struct g_shsec_softc *sc;
192 	struct g_geom *gp;
193 	int error;
194 
195 	gp = pp->geom;
196 	sc = gp->softc;
197 
198 	if (sc == NULL) {
199 		/*
200 		 * It looks like geom is being withered.
201 		 * In that case we allow only negative requests.
202 		 */
203 		KASSERT(dr <= 0 && dw <= 0 && de <= 0,
204 		    ("Positive access request (device=%s).", pp->name));
205 		if ((pp->acr + dr) == 0 && (pp->acw + dw) == 0 &&
206 		    (pp->ace + de) == 0) {
207 			G_SHSEC_DEBUG(0, "Device %s definitely destroyed.",
208 			    gp->name);
209 		}
210 		return (0);
211 	}
212 
213 	/* On first open, grab an extra "exclusive" bit */
214 	if (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)
215 		de++;
216 	/* ... and let go of it on last close */
217 	if ((pp->acr + dr) == 0 && (pp->acw + dw) == 0 && (pp->ace + de) == 0)
218 		de--;
219 
220 	error = ENXIO;
221 	LIST_FOREACH(cp1, &gp->consumer, consumer) {
222 		error = g_access(cp1, dr, dw, de);
223 		if (error == 0)
224 			continue;
225 		/*
226 		 * If we fail here, backout all previous changes.
227 		 */
228 		LIST_FOREACH(cp2, &gp->consumer, consumer) {
229 			if (cp1 == cp2)
230 				return (error);
231 			g_access(cp2, -dr, -dw, -de);
232 		}
233 		/* NOTREACHED */
234 	}
235 
236 	return (error);
237 }
238 
239 static void
240 g_shsec_xor1(uint32_t *src, uint32_t *dst, ssize_t len)
241 {
242 
243 	for (; len > 0; len -= sizeof(uint32_t), dst++)
244 		*dst = *dst ^ *src++;
245 	KASSERT(len == 0, ("len != 0 (len=%zd)", len));
246 }
247 
248 static void
249 g_shsec_done(struct bio *bp)
250 {
251 	struct g_shsec_softc *sc;
252 	struct bio *pbp;
253 
254 	pbp = bp->bio_parent;
255 	sc = pbp->bio_to->geom->softc;
256 	if (bp->bio_error == 0)
257 		G_SHSEC_LOGREQ(2, bp, "Request done.");
258 	else {
259 		G_SHSEC_LOGREQ(0, bp, "Request failed (error=%d).",
260 		    bp->bio_error);
261 		if (pbp->bio_error == 0)
262 			pbp->bio_error = bp->bio_error;
263 	}
264 	if (pbp->bio_cmd == BIO_READ) {
265 		if ((pbp->bio_pflags & G_SHSEC_BFLAG_FIRST) != 0) {
266 			bcopy(bp->bio_data, pbp->bio_data, pbp->bio_length);
267 			pbp->bio_pflags = 0;
268 		} else {
269 			g_shsec_xor1((uint32_t *)bp->bio_data,
270 			    (uint32_t *)pbp->bio_data,
271 			    (ssize_t)pbp->bio_length);
272 		}
273 	}
274 	bzero(bp->bio_data, bp->bio_length);
275 	uma_zfree(g_shsec_zone, bp->bio_data);
276 	g_destroy_bio(bp);
277 	pbp->bio_inbed++;
278 	if (pbp->bio_children == pbp->bio_inbed) {
279 		pbp->bio_completed = pbp->bio_length;
280 		g_io_deliver(pbp, pbp->bio_error);
281 	}
282 }
283 
284 static void
285 g_shsec_xor2(uint32_t *rand, uint32_t *dst, ssize_t len)
286 {
287 
288 	for (; len > 0; len -= sizeof(uint32_t), dst++) {
289 		*rand = arc4random();
290 		*dst = *dst ^ *rand++;
291 	}
292 	KASSERT(len == 0, ("len != 0 (len=%zd)", len));
293 }
294 
295 static void
296 g_shsec_start(struct bio *bp)
297 {
298 	TAILQ_HEAD(, bio) queue = TAILQ_HEAD_INITIALIZER(queue);
299 	struct g_shsec_softc *sc;
300 	struct bio *cbp;
301 	uint32_t *dst;
302 	ssize_t len;
303 	u_int no;
304 	int error;
305 
306 	sc = bp->bio_to->geom->softc;
307 	/*
308 	 * If sc == NULL, provider's error should be set and g_shsec_start()
309 	 * should not be called at all.
310 	 */
311 	KASSERT(sc != NULL,
312 	    ("Provider's error should be set (error=%d)(device=%s).",
313 	    bp->bio_to->error, bp->bio_to->name));
314 
315 	G_SHSEC_LOGREQ(2, bp, "Request received.");
316 
317 	switch (bp->bio_cmd) {
318 	case BIO_READ:
319 	case BIO_WRITE:
320 	case BIO_FLUSH:
321 		/*
322 		 * Only those requests are supported.
323 		 */
324 		break;
325 	case BIO_DELETE:
326 	case BIO_GETATTR:
327 		/* To which provider it should be delivered? */
328 	default:
329 		g_io_deliver(bp, EOPNOTSUPP);
330 		return;
331 	}
332 
333 	/*
334 	 * Allocate all bios first and calculate XOR.
335 	 */
336 	dst = NULL;
337 	len = bp->bio_length;
338 	if (bp->bio_cmd == BIO_READ)
339 		bp->bio_pflags = G_SHSEC_BFLAG_FIRST;
340 	for (no = 0; no < sc->sc_ndisks; no++) {
341 		cbp = g_clone_bio(bp);
342 		if (cbp == NULL) {
343 			error = ENOMEM;
344 			goto failure;
345 		}
346 		TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
347 
348 		/*
349 		 * Fill in the component buf structure.
350 		 */
351 		cbp->bio_done = g_shsec_done;
352 		cbp->bio_data = uma_zalloc(g_shsec_zone, M_NOWAIT);
353 		if (cbp->bio_data == NULL) {
354 			g_shsec_alloc_failed++;
355 			error = ENOMEM;
356 			goto failure;
357 		}
358 		cbp->bio_caller2 = sc->sc_disks[no];
359 		if (bp->bio_cmd == BIO_WRITE) {
360 			if (no == 0) {
361 				dst = (uint32_t *)cbp->bio_data;
362 				bcopy(bp->bio_data, dst, len);
363 			} else {
364 				g_shsec_xor2((uint32_t *)cbp->bio_data, dst,
365 				    len);
366 			}
367 		}
368 	}
369 	/*
370 	 * Fire off all allocated requests!
371 	 */
372 	while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
373 		struct g_consumer *cp;
374 
375 		TAILQ_REMOVE(&queue, cbp, bio_queue);
376 		cp = cbp->bio_caller2;
377 		cbp->bio_caller2 = NULL;
378 		cbp->bio_to = cp->provider;
379 		G_SHSEC_LOGREQ(2, cbp, "Sending request.");
380 		g_io_request(cbp, cp);
381 	}
382 	return;
383 failure:
384 	while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
385 		TAILQ_REMOVE(&queue, cbp, bio_queue);
386 		bp->bio_children--;
387 		if (cbp->bio_data != NULL) {
388 			bzero(cbp->bio_data, cbp->bio_length);
389 			uma_zfree(g_shsec_zone, cbp->bio_data);
390 		}
391 		g_destroy_bio(cbp);
392 	}
393 	if (bp->bio_error == 0)
394 		bp->bio_error = error;
395 	g_io_deliver(bp, bp->bio_error);
396 }
397 
398 static void
399 g_shsec_check_and_run(struct g_shsec_softc *sc)
400 {
401 	off_t mediasize, ms;
402 	u_int no, sectorsize = 0;
403 
404 	if (g_shsec_nvalid(sc) != sc->sc_ndisks)
405 		return;
406 
407 	sc->sc_provider = g_new_providerf(sc->sc_geom, "shsec/%s", sc->sc_name);
408 	/*
409 	 * Find the smallest disk.
410 	 */
411 	mediasize = sc->sc_disks[0]->provider->mediasize;
412 	mediasize -= sc->sc_disks[0]->provider->sectorsize;
413 	sectorsize = sc->sc_disks[0]->provider->sectorsize;
414 	for (no = 1; no < sc->sc_ndisks; no++) {
415 		ms = sc->sc_disks[no]->provider->mediasize;
416 		ms -= sc->sc_disks[no]->provider->sectorsize;
417 		if (ms < mediasize)
418 			mediasize = ms;
419 		sectorsize = lcm(sectorsize,
420 		    sc->sc_disks[no]->provider->sectorsize);
421 	}
422 	sc->sc_provider->sectorsize = sectorsize;
423 	sc->sc_provider->mediasize = mediasize;
424 	g_error_provider(sc->sc_provider, 0);
425 
426 	G_SHSEC_DEBUG(0, "Device %s activated.", sc->sc_name);
427 }
428 
429 static int
430 g_shsec_read_metadata(struct g_consumer *cp, struct g_shsec_metadata *md)
431 {
432 	struct g_provider *pp;
433 	u_char *buf;
434 	int error;
435 
436 	g_topology_assert();
437 
438 	error = g_access(cp, 1, 0, 0);
439 	if (error != 0)
440 		return (error);
441 	pp = cp->provider;
442 	g_topology_unlock();
443 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
444 	    &error);
445 	g_topology_lock();
446 	g_access(cp, -1, 0, 0);
447 	if (buf == NULL)
448 		return (error);
449 
450 	/* Decode metadata. */
451 	shsec_metadata_decode(buf, md);
452 	g_free(buf);
453 
454 	return (0);
455 }
456 
457 /*
458  * Add disk to given device.
459  */
460 static int
461 g_shsec_add_disk(struct g_shsec_softc *sc, struct g_provider *pp, u_int no)
462 {
463 	struct g_consumer *cp, *fcp;
464 	struct g_geom *gp;
465 	struct g_shsec_metadata md;
466 	int error;
467 
468 	/* Metadata corrupted? */
469 	if (no >= sc->sc_ndisks)
470 		return (EINVAL);
471 
472 	/* Check if disk is not already attached. */
473 	if (sc->sc_disks[no] != NULL)
474 		return (EEXIST);
475 
476 	gp = sc->sc_geom;
477 	fcp = LIST_FIRST(&gp->consumer);
478 
479 	cp = g_new_consumer(gp);
480 	error = g_attach(cp, pp);
481 	if (error != 0) {
482 		g_destroy_consumer(cp);
483 		return (error);
484 	}
485 
486 	if (fcp != NULL && (fcp->acr > 0 || fcp->acw > 0 || fcp->ace > 0)) {
487 		error = g_access(cp, fcp->acr, fcp->acw, fcp->ace);
488 		if (error != 0) {
489 			g_detach(cp);
490 			g_destroy_consumer(cp);
491 			return (error);
492 		}
493 	}
494 
495 	/* Reread metadata. */
496 	error = g_shsec_read_metadata(cp, &md);
497 	if (error != 0)
498 		goto fail;
499 
500 	if (strcmp(md.md_magic, G_SHSEC_MAGIC) != 0 ||
501 	    strcmp(md.md_name, sc->sc_name) != 0 || md.md_id != sc->sc_id) {
502 		G_SHSEC_DEBUG(0, "Metadata on %s changed.", pp->name);
503 		goto fail;
504 	}
505 
506 	cp->private = sc;
507 	cp->index = no;
508 	sc->sc_disks[no] = cp;
509 
510 	G_SHSEC_DEBUG(0, "Disk %s attached to %s.", pp->name, sc->sc_name);
511 
512 	g_shsec_check_and_run(sc);
513 
514 	return (0);
515 fail:
516 	if (fcp != NULL && (fcp->acr > 0 || fcp->acw > 0 || fcp->ace > 0))
517 		g_access(cp, -fcp->acr, -fcp->acw, -fcp->ace);
518 	g_detach(cp);
519 	g_destroy_consumer(cp);
520 	return (error);
521 }
522 
523 static struct g_geom *
524 g_shsec_create(struct g_class *mp, const struct g_shsec_metadata *md)
525 {
526 	struct g_shsec_softc *sc;
527 	struct g_geom *gp;
528 	u_int no;
529 
530 	G_SHSEC_DEBUG(1, "Creating device %s (id=%u).", md->md_name, md->md_id);
531 
532 	/* Two disks is minimum. */
533 	if (md->md_all < 2) {
534 		G_SHSEC_DEBUG(0, "Too few disks defined for %s.", md->md_name);
535 		return (NULL);
536 	}
537 
538 	/* Check for duplicate unit */
539 	LIST_FOREACH(gp, &mp->geom, geom) {
540 		sc = gp->softc;
541 		if (sc != NULL && strcmp(sc->sc_name, md->md_name) == 0) {
542 			G_SHSEC_DEBUG(0, "Device %s already configured.",
543 			    sc->sc_name);
544 			return (NULL);
545 		}
546 	}
547 	gp = g_new_geomf(mp, "%s", md->md_name);
548 	gp->softc = NULL;	/* for a moment */
549 
550 	sc = malloc(sizeof(*sc), M_SHSEC, M_WAITOK | M_ZERO);
551 	gp->start = g_shsec_start;
552 	gp->spoiled = g_shsec_orphan;
553 	gp->orphan = g_shsec_orphan;
554 	gp->access = g_shsec_access;
555 	gp->dumpconf = g_shsec_dumpconf;
556 
557 	sc->sc_id = md->md_id;
558 	sc->sc_ndisks = md->md_all;
559 	sc->sc_disks = malloc(sizeof(struct g_consumer *) * sc->sc_ndisks,
560 	    M_SHSEC, M_WAITOK | M_ZERO);
561 	for (no = 0; no < sc->sc_ndisks; no++)
562 		sc->sc_disks[no] = NULL;
563 
564 	gp->softc = sc;
565 	sc->sc_geom = gp;
566 	sc->sc_provider = NULL;
567 
568 	G_SHSEC_DEBUG(0, "Device %s created (id=%u).", sc->sc_name, sc->sc_id);
569 
570 	return (gp);
571 }
572 
573 static int
574 g_shsec_destroy(struct g_shsec_softc *sc, boolean_t force)
575 {
576 	struct g_provider *pp;
577 	struct g_geom *gp;
578 	u_int no;
579 
580 	g_topology_assert();
581 
582 	if (sc == NULL)
583 		return (ENXIO);
584 
585 	pp = sc->sc_provider;
586 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
587 		if (force) {
588 			G_SHSEC_DEBUG(0, "Device %s is still open, so it "
589 			    "can't be definitely removed.", pp->name);
590 		} else {
591 			G_SHSEC_DEBUG(1,
592 			    "Device %s is still open (r%dw%de%d).", pp->name,
593 			    pp->acr, pp->acw, pp->ace);
594 			return (EBUSY);
595 		}
596 	}
597 
598 	for (no = 0; no < sc->sc_ndisks; no++) {
599 		if (sc->sc_disks[no] != NULL)
600 			g_shsec_remove_disk(sc->sc_disks[no]);
601 	}
602 
603 	gp = sc->sc_geom;
604 	gp->softc = NULL;
605 	KASSERT(sc->sc_provider == NULL, ("Provider still exists? (device=%s)",
606 	    gp->name));
607 	free(sc->sc_disks, M_SHSEC);
608 	free(sc, M_SHSEC);
609 
610 	pp = LIST_FIRST(&gp->provider);
611 	if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0))
612 		G_SHSEC_DEBUG(0, "Device %s destroyed.", gp->name);
613 
614 	g_wither_geom(gp, ENXIO);
615 
616 	return (0);
617 }
618 
619 static int
620 g_shsec_destroy_geom(struct gctl_req *req __unused, struct g_class *mp __unused,
621     struct g_geom *gp)
622 {
623 	struct g_shsec_softc *sc;
624 
625 	sc = gp->softc;
626 	return (g_shsec_destroy(sc, 0));
627 }
628 
629 static struct g_geom *
630 g_shsec_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
631 {
632 	struct g_shsec_metadata md;
633 	struct g_shsec_softc *sc;
634 	struct g_consumer *cp;
635 	struct g_geom *gp;
636 	int error;
637 
638 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
639 	g_topology_assert();
640 
641 	G_SHSEC_DEBUG(3, "Tasting %s.", pp->name);
642 
643 	gp = g_new_geomf(mp, "shsec:taste");
644 	gp->start = g_shsec_start;
645 	gp->access = g_shsec_access;
646 	gp->orphan = g_shsec_orphan;
647 	cp = g_new_consumer(gp);
648 	g_attach(cp, pp);
649 	error = g_shsec_read_metadata(cp, &md);
650 	g_detach(cp);
651 	g_destroy_consumer(cp);
652 	g_destroy_geom(gp);
653 	if (error != 0)
654 		return (NULL);
655 	gp = NULL;
656 
657 	if (strcmp(md.md_magic, G_SHSEC_MAGIC) != 0)
658 		return (NULL);
659 	if (md.md_version > G_SHSEC_VERSION) {
660 		G_SHSEC_DEBUG(0, "Kernel module is too old to handle %s.\n",
661 		    pp->name);
662 		return (NULL);
663 	}
664 	/*
665 	 * Backward compatibility:
666 	 */
667 	/* There was no md_provsize field in earlier versions of metadata. */
668 	if (md.md_version < 1)
669 		md.md_provsize = pp->mediasize;
670 
671 	if (md.md_provider[0] != '\0' && strcmp(md.md_provider, pp->name) != 0)
672 		return (NULL);
673 	if (md.md_provsize != pp->mediasize)
674 		return (NULL);
675 
676 	/*
677 	 * Let's check if device already exists.
678 	 */
679 	sc = NULL;
680 	LIST_FOREACH(gp, &mp->geom, geom) {
681 		sc = gp->softc;
682 		if (sc == NULL)
683 			continue;
684 		if (strcmp(md.md_name, sc->sc_name) != 0)
685 			continue;
686 		if (md.md_id != sc->sc_id)
687 			continue;
688 		break;
689 	}
690 	if (gp != NULL) {
691 		G_SHSEC_DEBUG(1, "Adding disk %s to %s.", pp->name, gp->name);
692 		error = g_shsec_add_disk(sc, pp, md.md_no);
693 		if (error != 0) {
694 			G_SHSEC_DEBUG(0, "Cannot add disk %s to %s (error=%d).",
695 			    pp->name, gp->name, error);
696 			return (NULL);
697 		}
698 	} else {
699 		gp = g_shsec_create(mp, &md);
700 		if (gp == NULL) {
701 			G_SHSEC_DEBUG(0, "Cannot create device %s.", md.md_name);
702 			return (NULL);
703 		}
704 		sc = gp->softc;
705 		G_SHSEC_DEBUG(1, "Adding disk %s to %s.", pp->name, gp->name);
706 		error = g_shsec_add_disk(sc, pp, md.md_no);
707 		if (error != 0) {
708 			G_SHSEC_DEBUG(0, "Cannot add disk %s to %s (error=%d).",
709 			    pp->name, gp->name, error);
710 			g_shsec_destroy(sc, 1);
711 			return (NULL);
712 		}
713 	}
714 	return (gp);
715 }
716 
717 static struct g_shsec_softc *
718 g_shsec_find_device(struct g_class *mp, const char *name)
719 {
720 	struct g_shsec_softc *sc;
721 	struct g_geom *gp;
722 
723 	LIST_FOREACH(gp, &mp->geom, geom) {
724 		sc = gp->softc;
725 		if (sc == NULL)
726 			continue;
727 		if (strcmp(sc->sc_name, name) == 0)
728 			return (sc);
729 	}
730 	return (NULL);
731 }
732 
733 static void
734 g_shsec_ctl_destroy(struct gctl_req *req, struct g_class *mp)
735 {
736 	struct g_shsec_softc *sc;
737 	int *force, *nargs, error;
738 	const char *name;
739 	char param[16];
740 	u_int i;
741 
742 	g_topology_assert();
743 
744 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
745 	if (nargs == NULL) {
746 		gctl_error(req, "No '%s' argument.", "nargs");
747 		return;
748 	}
749 	if (*nargs <= 0) {
750 		gctl_error(req, "Missing device(s).");
751 		return;
752 	}
753 	force = gctl_get_paraml(req, "force", sizeof(*force));
754 	if (force == NULL) {
755 		gctl_error(req, "No '%s' argument.", "force");
756 		return;
757 	}
758 
759 	for (i = 0; i < (u_int)*nargs; i++) {
760 		snprintf(param, sizeof(param), "arg%u", i);
761 		name = gctl_get_asciiparam(req, param);
762 		if (name == NULL) {
763 			gctl_error(req, "No 'arg%u' argument.", i);
764 			return;
765 		}
766 		sc = g_shsec_find_device(mp, name);
767 		if (sc == NULL) {
768 			gctl_error(req, "No such device: %s.", name);
769 			return;
770 		}
771 		error = g_shsec_destroy(sc, *force);
772 		if (error != 0) {
773 			gctl_error(req, "Cannot destroy device %s (error=%d).",
774 			    sc->sc_name, error);
775 			return;
776 		}
777 	}
778 }
779 
780 static void
781 g_shsec_config(struct gctl_req *req, struct g_class *mp, const char *verb)
782 {
783 	uint32_t *version;
784 
785 	g_topology_assert();
786 
787 	version = gctl_get_paraml(req, "version", sizeof(*version));
788 	if (version == NULL) {
789 		gctl_error(req, "No '%s' argument.", "version");
790 		return;
791 	}
792 	if (*version != G_SHSEC_VERSION) {
793 		gctl_error(req, "Userland and kernel parts are out of sync.");
794 		return;
795 	}
796 
797 	if (strcmp(verb, "stop") == 0) {
798 		g_shsec_ctl_destroy(req, mp);
799 		return;
800 	}
801 
802 	gctl_error(req, "Unknown verb.");
803 }
804 
805 static void
806 g_shsec_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
807     struct g_consumer *cp, struct g_provider *pp)
808 {
809 	struct g_shsec_softc *sc;
810 
811 	sc = gp->softc;
812 	if (sc == NULL)
813 		return;
814 	if (pp != NULL) {
815 		/* Nothing here. */
816 	} else if (cp != NULL) {
817 		sbuf_printf(sb, "%s<Number>%u</Number>\n", indent,
818 		    (u_int)cp->index);
819 	} else {
820 		sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)sc->sc_id);
821 		sbuf_printf(sb, "%s<Status>Total=%u, Online=%u</Status>\n",
822 		    indent, sc->sc_ndisks, g_shsec_nvalid(sc));
823 		sbuf_printf(sb, "%s<State>", indent);
824 		if (sc->sc_provider != NULL && sc->sc_provider->error == 0)
825 			sbuf_printf(sb, "UP");
826 		else
827 			sbuf_printf(sb, "DOWN");
828 		sbuf_printf(sb, "</State>\n");
829 	}
830 }
831 
832 DECLARE_GEOM_CLASS(g_shsec_class, g_shsec);
833