xref: /freebsd/sys/geom/linux_lvm/g_linux_lvm.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2008 Andrew Thompson <thompsa@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 #include <sys/ctype.h>
31 #include <sys/param.h>
32 #include <sys/bio.h>
33 #include <sys/kernel.h>
34 #include <sys/limits.h>
35 #include <sys/malloc.h>
36 #include <sys/queue.h>
37 #include <sys/sysctl.h>
38 #include <sys/systm.h>
39 
40 #include <geom/geom.h>
41 #include <geom/geom_dbg.h>
42 #include <sys/endian.h>
43 
44 #include <geom/linux_lvm/g_linux_lvm.h>
45 
46 FEATURE(geom_linux_lvm, "GEOM Linux LVM partitioning support");
47 
48 /* Declare malloc(9) label */
49 static MALLOC_DEFINE(M_GLLVM, "gllvm", "GEOM_LINUX_LVM Data");
50 
51 /* GEOM class methods */
52 static g_access_t g_llvm_access;
53 static g_init_t g_llvm_init;
54 static g_orphan_t g_llvm_orphan;
55 static g_orphan_t g_llvm_taste_orphan;
56 static g_start_t g_llvm_start;
57 static g_taste_t g_llvm_taste;
58 static g_ctl_destroy_geom_t g_llvm_destroy_geom;
59 
60 static void	g_llvm_done(struct bio *);
61 static void	g_llvm_remove_disk(struct g_llvm_vg *, struct g_consumer *);
62 static int	g_llvm_activate_lv(struct g_llvm_vg *, struct g_llvm_lv *);
63 static int	g_llvm_add_disk(struct g_llvm_vg *, struct g_provider *, char *);
64 static void	g_llvm_free_vg(struct g_llvm_vg *);
65 static int	g_llvm_destroy(struct g_llvm_vg *, int);
66 static int	g_llvm_read_label(struct g_consumer *, struct g_llvm_label *);
67 static int	g_llvm_read_md(struct g_consumer *, struct g_llvm_metadata *,
68 		    struct g_llvm_label *);
69 
70 static int	llvm_label_decode(const u_char *, struct g_llvm_label *,
71 		    int, u_int);
72 static int	llvm_md_decode(const u_char *, struct g_llvm_metadata *,
73 		    struct g_llvm_label *);
74 static int	llvm_textconf_decode(u_char *, int,
75 		    struct g_llvm_metadata *);
76 static int	llvm_textconf_decode_pv(char **, char *, struct g_llvm_vg *);
77 static int	llvm_textconf_decode_lv(char **, char *, struct g_llvm_vg *);
78 static int	llvm_textconf_decode_sg(char **, char *, struct g_llvm_lv *);
79 
80 SYSCTL_DECL(_kern_geom);
81 SYSCTL_NODE(_kern_geom, OID_AUTO, linux_lvm, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
82     "GEOM_LINUX_LVM stuff");
83 static u_int g_llvm_debug = 0;
84 SYSCTL_UINT(_kern_geom_linux_lvm, OID_AUTO, debug, CTLFLAG_RWTUN, &g_llvm_debug, 0,
85     "Debug level");
86 
87 LIST_HEAD(, g_llvm_vg) vg_list;
88 
89 /*
90  * Called to notify geom when it's been opened, and for what intent
91  */
92 static int
93 g_llvm_access(struct g_provider *pp, int dr, int dw, int de)
94 {
95 	struct g_consumer *c;
96 	struct g_llvm_vg *vg;
97 	struct g_geom *gp;
98 	int error;
99 
100 	KASSERT(pp != NULL, ("%s: NULL provider", __func__));
101 	gp = pp->geom;
102 	KASSERT(gp != NULL, ("%s: NULL geom", __func__));
103 	vg = gp->softc;
104 
105 	if (vg == NULL) {
106 		/* It seems that .access can be called with negative dr,dw,dx
107 		 * in this case but I want to check for myself */
108 		G_LLVM_DEBUG(0, "access(%d, %d, %d) for %s",
109 		    dr, dw, de, pp->name);
110 
111 		/* This should only happen when geom is withered so
112 		 * allow only negative requests */
113 		KASSERT(dr <= 0 && dw <= 0 && de <= 0,
114 		    ("%s: Positive access for %s", __func__, pp->name));
115 		if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0)
116 			G_LLVM_DEBUG(0,
117 			    "Device %s definitely destroyed", pp->name);
118 		return (0);
119 	}
120 
121 	/* Grab an exclusive bit to propagate on our consumers on first open */
122 	if (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)
123 		de++;
124 	/* ... drop it on close */
125 	if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0)
126 		de--;
127 
128 	error = ENXIO;
129 	LIST_FOREACH(c, &gp->consumer, consumer) {
130 		KASSERT(c != NULL, ("%s: consumer is NULL", __func__));
131 		error = g_access(c, dr, dw, de);
132 		if (error != 0) {
133 			struct g_consumer *c2;
134 
135 			/* Backout earlier changes */
136 			LIST_FOREACH(c2, &gp->consumer, consumer) {
137 				if (c2 == c) /* all eariler components fixed */
138 					return (error);
139 				g_access(c2, -dr, -dw, -de);
140 			}
141 		}
142 	}
143 
144 	return (error);
145 }
146 
147 /*
148  * Dismantle bio_queue and destroy its components
149  */
150 static void
151 bioq_dismantle(struct bio_queue_head *bq)
152 {
153 	struct bio *b;
154 
155 	for (b = bioq_first(bq); b != NULL; b = bioq_first(bq)) {
156 		bioq_remove(bq, b);
157 		g_destroy_bio(b);
158 	}
159 }
160 
161 /*
162  * GEOM .done handler
163  * Can't use standard handler because one requested IO may
164  * fork into additional data IOs
165  */
166 static void
167 g_llvm_done(struct bio *b)
168 {
169 	struct bio *parent_b;
170 
171 	parent_b = b->bio_parent;
172 
173 	if (b->bio_error != 0) {
174 		G_LLVM_DEBUG(0, "Error %d for offset=%ju, length=%ju on %s",
175 		    b->bio_error, b->bio_offset, b->bio_length,
176 		    b->bio_to->name);
177 		if (parent_b->bio_error == 0)
178 			parent_b->bio_error = b->bio_error;
179 	}
180 
181 	parent_b->bio_inbed++;
182 	parent_b->bio_completed += b->bio_completed;
183 
184 	if (parent_b->bio_children == parent_b->bio_inbed) {
185 		parent_b->bio_completed = parent_b->bio_length;
186 		g_io_deliver(parent_b, parent_b->bio_error);
187 	}
188 	g_destroy_bio(b);
189 }
190 
191 static void
192 g_llvm_start(struct bio *bp)
193 {
194 	struct g_provider *pp;
195 	struct g_llvm_vg *vg;
196 	struct g_llvm_pv *pv;
197 	struct g_llvm_lv *lv;
198 	struct g_llvm_segment *sg;
199 	struct bio *cb;
200 	struct bio_queue_head bq;
201 	size_t chunk_size;
202 	off_t offset, length;
203 	char *addr;
204 	u_int count;
205 
206 	pp = bp->bio_to;
207 	lv = pp->private;
208 	vg = pp->geom->softc;
209 
210 	switch (bp->bio_cmd) {
211 	case BIO_READ:
212 	case BIO_WRITE:
213 	case BIO_DELETE:
214 	/* XXX BIO_GETATTR allowed? */
215 		break;
216 	default:
217 		/*
218 		 * BIO_SPEEDUP and BIO_FLUSH should pass through to all sg
219 		 * elements, but aren't.
220 		 */
221 		g_io_deliver(bp, EOPNOTSUPP);
222 		return;
223 	}
224 
225 	bioq_init(&bq);
226 
227 	chunk_size = vg->vg_extentsize;
228 	addr = bp->bio_data;
229 	offset = bp->bio_offset;	/* virtual offset and length */
230 	length = bp->bio_length;
231 
232 	while (length > 0) {
233 		size_t chunk_index, in_chunk_offset, in_chunk_length;
234 
235 		pv = NULL;
236 		cb = g_clone_bio(bp);
237 		if (cb == NULL) {
238 			bioq_dismantle(&bq);
239 			if (bp->bio_error == 0)
240 				bp->bio_error = ENOMEM;
241 			g_io_deliver(bp, bp->bio_error);
242 			return;
243 		}
244 
245 		/* get the segment and the pv */
246 		if (lv->lv_sgcount == 1) {
247 			/* skip much of the calculations for a single sg */
248 			chunk_index = 0;
249 			in_chunk_offset = 0;
250 			in_chunk_length = length;
251 			sg = lv->lv_firstsg;
252 			pv = sg->sg_pv;
253 			cb->bio_offset = offset + sg->sg_pvoffset;
254 		} else {
255 			chunk_index = offset / chunk_size; /* round downwards */
256 			in_chunk_offset = offset % chunk_size;
257 			in_chunk_length =
258 			    min(length, chunk_size - in_chunk_offset);
259 
260 			/* XXX could be faster */
261 			LIST_FOREACH(sg, &lv->lv_segs, sg_next) {
262 				if (chunk_index >= sg->sg_start &&
263 				    chunk_index <= sg->sg_end) {
264 					/* adjust chunk index for sg start */
265 					chunk_index -= sg->sg_start;
266 					pv = sg->sg_pv;
267 					break;
268 				}
269 			}
270 			cb->bio_offset =
271 			    (off_t)chunk_index * (off_t)chunk_size
272 			    + in_chunk_offset + sg->sg_pvoffset;
273 		}
274 
275 		KASSERT(pv != NULL, ("Can't find PV for chunk %zu",
276 		    chunk_index));
277 
278 		cb->bio_to = pv->pv_gprov;
279 		cb->bio_done = g_llvm_done;
280 		cb->bio_length = in_chunk_length;
281 		cb->bio_data = addr;
282 		cb->bio_caller1 = pv;
283 		bioq_disksort(&bq, cb);
284 
285 		G_LLVM_DEBUG(5,
286 		    "Mapped %s(%ju, %ju) on %s to %zu(%zu,%zu) @ %s:%ju",
287 		    bp->bio_cmd == BIO_READ ? "R" : "W",
288 		    offset, length, lv->lv_name,
289 		    chunk_index, in_chunk_offset, in_chunk_length,
290 		    pv->pv_name, cb->bio_offset);
291 
292 		addr += in_chunk_length;
293 		length -= in_chunk_length;
294 		offset += in_chunk_length;
295 	}
296 
297 	/* Fire off bio's here */
298 	count = 0;
299 	for (cb = bioq_first(&bq); cb != NULL; cb = bioq_first(&bq)) {
300 		bioq_remove(&bq, cb);
301 		pv = cb->bio_caller1;
302 		cb->bio_caller1 = NULL;
303 		G_LLVM_DEBUG(6, "firing bio to %s, offset=%ju, length=%ju",
304 		    cb->bio_to->name, cb->bio_offset, cb->bio_length);
305 		g_io_request(cb, pv->pv_gcons);
306 		count++;
307 	}
308 	if (count == 0) { /* We handled everything locally */
309 		bp->bio_completed = bp->bio_length;
310 		g_io_deliver(bp, 0);
311 	}
312 }
313 
314 static void
315 g_llvm_remove_disk(struct g_llvm_vg *vg, struct g_consumer *cp)
316 {
317 	struct g_llvm_pv *pv;
318 	struct g_llvm_lv *lv;
319 	struct g_llvm_segment *sg;
320 	int found;
321 
322 	KASSERT(cp != NULL, ("Non-valid disk in %s.", __func__));
323 	pv = (struct g_llvm_pv *)cp->private;
324 
325 	G_LLVM_DEBUG(0, "Disk %s removed from %s.", cp->provider->name,
326 	    pv->pv_name);
327 
328 	LIST_FOREACH(lv, &vg->vg_lvs, lv_next) {
329 		/* Find segments that map to this disk */
330 		found = 0;
331 		LIST_FOREACH(sg, &lv->lv_segs, sg_next) {
332 			if (sg->sg_pv == pv) {
333 				sg->sg_pv = NULL;
334 				lv->lv_sgactive--;
335 				found = 1;
336 				break;
337 			}
338 		}
339 		if (found) {
340 			G_LLVM_DEBUG(0, "Device %s removed.",
341 			    lv->lv_gprov->name);
342 			g_wither_provider(lv->lv_gprov, ENXIO);
343 			lv->lv_gprov = NULL;
344 		}
345 	}
346 
347 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
348 		g_access(cp, -cp->acr, -cp->acw, -cp->ace);
349 	g_detach(cp);
350 	g_destroy_consumer(cp);
351 }
352 
353 static void
354 g_llvm_orphan(struct g_consumer *cp)
355 {
356 	struct g_llvm_vg *vg;
357 	struct g_geom *gp;
358 
359 	g_topology_assert();
360 	gp = cp->geom;
361 	vg = gp->softc;
362 	if (vg == NULL)
363 		return;
364 
365 	g_llvm_remove_disk(vg, cp);
366 	g_llvm_destroy(vg, 1);
367 }
368 
369 static int
370 g_llvm_activate_lv(struct g_llvm_vg *vg, struct g_llvm_lv *lv)
371 {
372 	struct g_geom *gp;
373 	struct g_provider *pp;
374 
375 	g_topology_assert();
376 
377 	KASSERT(lv->lv_sgactive == lv->lv_sgcount, ("segment missing"));
378 
379 	gp = vg->vg_geom;
380 	pp = g_new_providerf(gp, "linux_lvm/%s-%s", vg->vg_name, lv->lv_name);
381 	pp->mediasize = vg->vg_extentsize * (off_t)lv->lv_extentcount;
382 	pp->sectorsize = vg->vg_sectorsize;
383 	g_error_provider(pp, 0);
384 	lv->lv_gprov = pp;
385 	pp->private = lv;
386 
387 	G_LLVM_DEBUG(1, "Created %s, %juM", pp->name,
388 	    pp->mediasize / (1024*1024));
389 
390 	return (0);
391 }
392 
393 static int
394 g_llvm_add_disk(struct g_llvm_vg *vg, struct g_provider *pp, char *uuid)
395 {
396 	struct g_geom *gp;
397 	struct g_consumer *cp, *fcp;
398 	struct g_llvm_pv *pv;
399 	struct g_llvm_lv *lv;
400 	struct g_llvm_segment *sg;
401 	int error;
402 
403 	g_topology_assert();
404 
405 	LIST_FOREACH(pv, &vg->vg_pvs, pv_next) {
406 		if (strcmp(pv->pv_uuid, uuid) == 0)
407 			break;	/* found it */
408 	}
409 	if (pv == NULL) {
410 		G_LLVM_DEBUG(3, "uuid %s not found in pv list", uuid);
411 		return (ENOENT);
412 	}
413 	if (pv->pv_gprov != NULL) {
414 		G_LLVM_DEBUG(0, "disk %s already initialised in %s",
415 		    pv->pv_name, vg->vg_name);
416 		return (EEXIST);
417 	}
418 
419 	pv->pv_start *= vg->vg_sectorsize;
420 	gp = vg->vg_geom;
421 	fcp = LIST_FIRST(&gp->consumer);
422 
423 	cp = g_new_consumer(gp);
424 	error = g_attach(cp, pp);
425 	G_LLVM_DEBUG(1, "Attached %s to %s at offset %ju",
426 	    pp->name, pv->pv_name, pv->pv_start);
427 
428 	if (error != 0) {
429 		G_LLVM_DEBUG(0, "cannot attach %s to %s",
430 		    pp->name, vg->vg_name);
431 		g_destroy_consumer(cp);
432 		return (error);
433 	}
434 
435 	if (fcp != NULL) {
436 		if (fcp->provider->sectorsize != pp->sectorsize) {
437 			G_LLVM_DEBUG(0, "Provider %s of %s has invalid "
438 			    "sector size (%d)", pp->name, vg->vg_name,
439 			    pp->sectorsize);
440 			return (EINVAL);
441 		}
442 		if (fcp->acr > 0 || fcp->acw || fcp->ace > 0) {
443 			/* Replicate access permissions from first "live"
444 			 * consumer to the new one */
445 			error = g_access(cp, fcp->acr, fcp->acw, fcp->ace);
446 			if (error != 0) {
447 				g_detach(cp);
448 				g_destroy_consumer(cp);
449 				return (error);
450 			}
451 		}
452 	}
453 
454 	cp->private = pv;
455 	pv->pv_gcons = cp;
456 	pv->pv_gprov = pp;
457 
458 	LIST_FOREACH(lv, &vg->vg_lvs, lv_next) {
459 		/* Find segments that map to this disk */
460 		LIST_FOREACH(sg, &lv->lv_segs, sg_next) {
461 			if (strcmp(sg->sg_pvname, pv->pv_name) == 0) {
462 				/* avtivate the segment */
463 				KASSERT(sg->sg_pv == NULL,
464 				    ("segment already mapped"));
465 				sg->sg_pvoffset =
466 				    (off_t)sg->sg_pvstart * vg->vg_extentsize
467 				    + pv->pv_start;
468 				sg->sg_pv = pv;
469 				lv->lv_sgactive++;
470 
471 				G_LLVM_DEBUG(2, "%s: %d to %d @ %s:%d"
472 				    " offset %ju sector %ju",
473 				    lv->lv_name, sg->sg_start, sg->sg_end,
474 				    sg->sg_pvname, sg->sg_pvstart,
475 				    sg->sg_pvoffset,
476 				    sg->sg_pvoffset / vg->vg_sectorsize);
477 			}
478 		}
479 		/* Activate any lvs waiting on this disk */
480 		if (lv->lv_gprov == NULL && lv->lv_sgactive == lv->lv_sgcount) {
481 			error = g_llvm_activate_lv(vg, lv);
482 			if (error)
483 				break;
484 		}
485 	}
486 	return (error);
487 }
488 
489 static void
490 g_llvm_init(struct g_class *mp)
491 {
492 	LIST_INIT(&vg_list);
493 }
494 
495 static void
496 g_llvm_free_vg(struct g_llvm_vg *vg)
497 {
498 	struct g_llvm_pv *pv;
499 	struct g_llvm_lv *lv;
500 	struct g_llvm_segment *sg;
501 
502 	/* Free all the structures */
503 	while ((pv = LIST_FIRST(&vg->vg_pvs)) != NULL) {
504 		LIST_REMOVE(pv, pv_next);
505 		free(pv, M_GLLVM);
506 	}
507 	while ((lv = LIST_FIRST(&vg->vg_lvs)) != NULL) {
508 		while ((sg = LIST_FIRST(&lv->lv_segs)) != NULL) {
509 			LIST_REMOVE(sg, sg_next);
510 			free(sg, M_GLLVM);
511 		}
512 		LIST_REMOVE(lv, lv_next);
513 		free(lv, M_GLLVM);
514 	}
515 	LIST_REMOVE(vg, vg_next);
516 	free(vg, M_GLLVM);
517 }
518 
519 static void
520 g_llvm_taste_orphan(struct g_consumer *cp)
521 {
522 
523 	KASSERT(1 == 0, ("%s called while tasting %s.", __func__,
524 	    cp->provider->name));
525 }
526 
527 static struct g_geom *
528 g_llvm_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
529 {
530 	struct g_consumer *cp;
531 	struct g_geom *gp;
532 	struct g_llvm_label ll;
533 	struct g_llvm_metadata md;
534 	struct g_llvm_vg *vg;
535 	int error;
536 
537 	bzero(&md, sizeof(md));
538 
539 	g_topology_assert();
540 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
541 	gp = g_new_geomf(mp, "linux_lvm:taste");
542 	/* This orphan function should be never called. */
543 	gp->orphan = g_llvm_taste_orphan;
544 	cp = g_new_consumer(gp);
545 	cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
546 	error = g_attach(cp, pp);
547 	if (error == 0) {
548 		error = g_llvm_read_label(cp, &ll);
549 		if (error == 0)
550 			error = g_llvm_read_md(cp, &md, &ll);
551 		g_detach(cp);
552 	}
553 	g_destroy_consumer(cp);
554 	g_destroy_geom(gp);
555 	if (error != 0)
556 		return (NULL);
557 
558 	vg = md.md_vg;
559 	if (vg->vg_geom == NULL) {
560 		/* new volume group */
561 		gp = g_new_geomf(mp, "%s", vg->vg_name);
562 		gp->start = g_llvm_start;
563 		gp->spoiled = g_llvm_orphan;
564 		gp->orphan = g_llvm_orphan;
565 		gp->access = g_llvm_access;
566 		vg->vg_sectorsize = pp->sectorsize;
567 		vg->vg_extentsize *= vg->vg_sectorsize;
568 		vg->vg_geom = gp;
569 		gp->softc = vg;
570 		G_LLVM_DEBUG(1, "Created volume %s, extent size %zuK",
571 		    vg->vg_name, vg->vg_extentsize / 1024);
572 	}
573 
574 	/* initialise this disk in the volume group */
575 	g_llvm_add_disk(vg, pp, ll.ll_uuid);
576 	return (vg->vg_geom);
577 }
578 
579 static int
580 g_llvm_destroy(struct g_llvm_vg *vg, int force)
581 {
582 	struct g_provider *pp;
583 	struct g_geom *gp;
584 
585 	g_topology_assert();
586 	if (vg == NULL)
587 		return (ENXIO);
588 	gp = vg->vg_geom;
589 
590 	LIST_FOREACH(pp, &gp->provider, provider) {
591 		if (pp->acr != 0 || pp->acw != 0 || pp->ace != 0) {
592 			G_LLVM_DEBUG(1, "Device %s is still open (r%dw%de%d)",
593 			    pp->name, pp->acr, pp->acw, pp->ace);
594 			if (!force)
595 				return (EBUSY);
596 		}
597 	}
598 
599 	g_llvm_free_vg(gp->softc);
600 	gp->softc = NULL;
601 	g_wither_geom(gp, ENXIO);
602 	return (0);
603 }
604 
605 static int
606 g_llvm_destroy_geom(struct gctl_req *req __unused, struct g_class *mp __unused,
607     struct g_geom *gp)
608 {
609 	struct g_llvm_vg *vg;
610 
611 	vg = gp->softc;
612 	return (g_llvm_destroy(vg, 0));
613 }
614 
615 int
616 g_llvm_read_label(struct g_consumer *cp, struct g_llvm_label *ll)
617 {
618 	struct g_provider *pp;
619 	u_char *buf;
620 	int i, error = 0;
621 
622 	g_topology_assert();
623 
624 	/* The LVM label is stored on the first four sectors */
625 	error = g_access(cp, 1, 0, 0);
626 	if (error != 0)
627 		return (error);
628 	pp = cp->provider;
629 	g_topology_unlock();
630 	buf = g_read_data(cp, 0, pp->sectorsize * 4, &error);
631 	g_topology_lock();
632 	g_access(cp, -1, 0, 0);
633 	if (buf == NULL) {
634 		G_LLVM_DEBUG(1, "Cannot read metadata from %s (error=%d)",
635 		    pp->name, error);
636 		return (error);
637 	}
638 
639 	/* Search the four sectors for the LVM label. */
640 	for (i = 0; i < 4; i++) {
641 		error = llvm_label_decode(&buf[i * pp->sectorsize], ll, i,
642 			    pp->sectorsize);
643 		if (error == 0)
644 			break;	/* found it */
645 	}
646 	g_free(buf);
647 	return (error);
648 }
649 
650 int
651 g_llvm_read_md(struct g_consumer *cp, struct g_llvm_metadata *md,
652     struct g_llvm_label *ll)
653 {
654 	struct g_provider *pp;
655 	u_char *buf;
656 	int error;
657 	int size;
658 
659 	g_topology_assert();
660 
661 	error = g_access(cp, 1, 0, 0);
662 	if (error != 0)
663 		return (error);
664 	pp = cp->provider;
665 	g_topology_unlock();
666 	buf = g_read_data(cp, ll->ll_md_offset, pp->sectorsize, &error);
667 	g_topology_lock();
668 	g_access(cp, -1, 0, 0);
669 	if (buf == NULL) {
670 		G_LLVM_DEBUG(0, "Cannot read metadata from %s (error=%d)",
671 		    cp->provider->name, error);
672 		return (error);
673 	}
674 
675 	error = llvm_md_decode(buf, md, ll);
676 	g_free(buf);
677 	if (error != 0) {
678 		return (error);
679 	}
680 
681 	G_LLVM_DEBUG(1, "reading LVM2 config @ %s:%ju", pp->name,
682 		    ll->ll_md_offset + md->md_reloffset);
683 	error = g_access(cp, 1, 0, 0);
684 	if (error != 0)
685 		return (error);
686 	pp = cp->provider;
687 	g_topology_unlock();
688 	/* round up to the nearest sector */
689 	size = md->md_relsize +
690 	    (pp->sectorsize - md->md_relsize % pp->sectorsize);
691 	buf = g_read_data(cp, ll->ll_md_offset + md->md_reloffset, size, &error);
692 	g_topology_lock();
693 	g_access(cp, -1, 0, 0);
694 	if (buf == NULL) {
695 		G_LLVM_DEBUG(0, "Cannot read LVM2 config from %s (error=%d)",
696 		    pp->name, error);
697 		return (error);
698 	}
699 	buf[md->md_relsize] = '\0';
700 	G_LLVM_DEBUG(10, "LVM config:\n%s\n", buf);
701 	error = llvm_textconf_decode(buf, md->md_relsize, md);
702 	g_free(buf);
703 
704 	return (error);
705 }
706 
707 static int
708 llvm_label_decode(const u_char *data, struct g_llvm_label *ll, int sector,
709     u_int sectorsize)
710 {
711 	uint64_t off;
712 	char *uuid;
713 
714 	/* Magic string */
715 	if (bcmp("LABELONE", data , 8) != 0)
716 		return (EINVAL);
717 
718 	/* We only support LVM2 text format */
719 	if (bcmp("LVM2 001", data + 24, 8) != 0) {
720 		G_LLVM_DEBUG(0, "Unsupported LVM format");
721 		return (EINVAL);
722 	}
723 
724 	ll->ll_sector = le64dec(data + 8);
725 	ll->ll_crc = le32dec(data + 16);
726 	ll->ll_offset = le32dec(data + 20);
727 
728 	if (ll->ll_sector != sector) {
729 		G_LLVM_DEBUG(0, "Expected sector %ju, found at %d",
730 		    ll->ll_sector, sector);
731 		return (EINVAL);
732 	}
733 
734 	/* XXX The minimal possible size of physical volume header is 88 */
735 	if (ll->ll_offset < 32 || ll->ll_offset > sectorsize - 88) {
736 		G_LLVM_DEBUG(0, "Invalid physical volume header offset %u",
737 		    ll->ll_offset);
738 		return (EINVAL);
739 	}
740 
741 	off = ll->ll_offset;
742 	/*
743 	 * convert the binary uuid to string format, the format is
744 	 * xxxxxx-xxxx-xxxx-xxxx-xxxx-xxxx-xxxxxx (6-4-4-4-4-4-6)
745 	 */
746 	uuid = ll->ll_uuid;
747 	bcopy(data + off, uuid, 6);
748 	off += 6;
749 	uuid += 6;
750 	*uuid++ = '-';
751 	for (int i = 0; i < 5; i++) {
752 		bcopy(data + off, uuid, 4);
753 		off += 4;
754 		uuid += 4;
755 		*uuid++ = '-';
756 	}
757 	bcopy(data + off, uuid, 6);
758 	off += 6;
759 	uuid += 6;
760 	*uuid++ = '\0';
761 
762 	ll->ll_size = le64dec(data + off);
763 	off += 8;
764 	ll->ll_pestart = le64dec(data + off);
765 	off += 16;
766 
767 	/* Only one data section is supported */
768 	if (le64dec(data + off) != 0) {
769 		G_LLVM_DEBUG(0, "Only one data section supported");
770 		return (EINVAL);
771 	}
772 
773 	off += 16;
774 	ll->ll_md_offset = le64dec(data + off);
775 	off += 8;
776 	ll->ll_md_size = le64dec(data + off);
777 	off += 8;
778 
779 	G_LLVM_DEBUG(1, "LVM metadata: offset=%ju, size=%ju", ll->ll_md_offset,
780 	    ll->ll_md_size);
781 
782 	/* Only one data section is supported */
783 	if (le64dec(data + off) != 0) {
784 		G_LLVM_DEBUG(0, "Only one metadata section supported");
785 		return (EINVAL);
786 	}
787 
788 	G_LLVM_DEBUG(2, "label uuid=%s", ll->ll_uuid);
789 	G_LLVM_DEBUG(2, "sector=%ju, crc=%u, offset=%u, size=%ju, pestart=%ju",
790 	    ll->ll_sector, ll->ll_crc, ll->ll_offset, ll->ll_size,
791 	    ll->ll_pestart);
792 
793 	return (0);
794 }
795 
796 static int
797 llvm_md_decode(const u_char *data, struct g_llvm_metadata *md,
798     struct g_llvm_label *ll)
799 {
800 	uint64_t off;
801 	char magic[16];
802 
803 	off = 0;
804 	md->md_csum = le32dec(data + off);
805 	off += 4;
806 	bcopy(data + off, magic, 16);
807 	off += 16;
808 	md->md_version = le32dec(data + off);
809 	off += 4;
810 	md->md_start = le64dec(data + off);
811 	off += 8;
812 	md->md_size = le64dec(data + off);
813 	off += 8;
814 
815 	if (bcmp(G_LLVM_MAGIC, magic, 16) != 0) {
816 		G_LLVM_DEBUG(0, "Incorrect md magic number");
817 		return (EINVAL);
818 	}
819 	if (md->md_version != 1) {
820 		G_LLVM_DEBUG(0, "Incorrect md version number (%u)",
821 		    md->md_version);
822 		return (EINVAL);
823 	}
824 	if (md->md_start != ll->ll_md_offset) {
825 		G_LLVM_DEBUG(0, "Incorrect md offset (%ju)", md->md_start);
826 		return (EINVAL);
827 	}
828 
829 	/* Aparently only one is ever returned */
830 	md->md_reloffset = le64dec(data + off);
831 	off += 8;
832 	md->md_relsize = le64dec(data + off);
833 	off += 16;	/* XXX skipped checksum */
834 
835 	if (le64dec(data + off) != 0) {
836 		G_LLVM_DEBUG(0, "Only one reloc supported");
837 		return (EINVAL);
838 	}
839 
840 	G_LLVM_DEBUG(3, "reloc: offset=%ju, size=%ju",
841 	    md->md_reloffset, md->md_relsize);
842 	G_LLVM_DEBUG(3, "md: version=%u, start=%ju, size=%ju",
843 	    md->md_version, md->md_start, md->md_size);
844 
845 	return (0);
846 }
847 
848 #define	GRAB_INT(key, tok1, tok2, v)					\
849 	if (tok1 && tok2 && strncmp(tok1, key, sizeof(key)) == 0) {	\
850 		v = strtol(tok2, &tok1, 10);				\
851 		if (tok1 == tok2)					\
852 			/* strtol did not eat any of the buffer */	\
853 			goto bad;					\
854 		continue;						\
855 	}
856 
857 #define	GRAB_STR(key, tok1, tok2, v, len)				\
858 	if (tok1 && tok2 && strncmp(tok1, key, sizeof(key)) == 0) {	\
859 		strsep(&tok2, "\"");					\
860 		if (tok2 == NULL)					\
861 			continue;					\
862 		tok1 = strsep(&tok2, "\"");				\
863 		if (tok2 == NULL)					\
864 			continue;					\
865 		strncpy(v, tok1, len);					\
866 		continue;						\
867 	}
868 
869 #define	SPLIT(key, value, str)						\
870 	key = strsep(&value, str);					\
871 	/* strip trailing whitespace on the key */			\
872 	for (char *t = key; *t != '\0'; t++)				\
873 		if (isspace(*t)) {					\
874 			*t = '\0';					\
875 			break;						\
876 		}
877 
878 static size_t
879 llvm_grab_name(char *name, const char *tok)
880 {
881 	size_t len;
882 
883 	len = 0;
884 	if (tok == NULL)
885 		return (0);
886 	if (tok[0] == '-')
887 		return (0);
888 	if (strcmp(tok, ".") == 0 || strcmp(tok, "..") == 0)
889 		return (0);
890 	while (tok[len] && (isalpha(tok[len]) || isdigit(tok[len]) ||
891 	    tok[len] == '.' || tok[len] == '_' || tok[len] == '-' ||
892 	    tok[len] == '+') && len < G_LLVM_NAMELEN - 1)
893 		len++;
894 	bcopy(tok, name, len);
895 	name[len] = '\0';
896 	return (len);
897 }
898 
899 static int
900 llvm_textconf_decode(u_char *data, int buflen, struct g_llvm_metadata *md)
901 {
902 	struct g_llvm_vg	*vg;
903 	char *buf = data;
904 	char *tok, *v;
905 	char name[G_LLVM_NAMELEN];
906 	char uuid[G_LLVM_UUIDLEN];
907 	size_t len;
908 
909 	if (buf == NULL || *buf == '\0')
910 		return (EINVAL);
911 
912 	tok = strsep(&buf, "\n");
913 	if (tok == NULL)
914 		return (EINVAL);
915 	len = llvm_grab_name(name, tok);
916 	if (len == 0)
917 		return (EINVAL);
918 
919 	/* check too see if the vg has already been loaded off another disk */
920 	LIST_FOREACH(vg, &vg_list, vg_next) {
921 		if (strcmp(vg->vg_name, name) == 0) {
922 			uuid[0] = '\0';
923 			/* grab the volume group uuid */
924 			while ((tok = strsep(&buf, "\n")) != NULL) {
925 				if (strstr(tok, "{"))
926 					break;
927 				if (strstr(tok, "=")) {
928 					SPLIT(v, tok, "=");
929 					GRAB_STR("id", v, tok, uuid,
930 					    sizeof(uuid));
931 				}
932 			}
933 			if (strcmp(vg->vg_uuid, uuid) == 0) {
934 				/* existing vg */
935 				md->md_vg = vg;
936 				return (0);
937 			}
938 			/* XXX different volume group with name clash! */
939 			G_LLVM_DEBUG(0,
940 			    "%s already exists, volume group not loaded", name);
941 			return (EINVAL);
942 		}
943 	}
944 
945 	vg = malloc(sizeof(*vg), M_GLLVM, M_NOWAIT|M_ZERO);
946 	if (vg == NULL)
947 		return (ENOMEM);
948 
949 	strncpy(vg->vg_name, name, sizeof(vg->vg_name));
950 	LIST_INIT(&vg->vg_pvs);
951 	LIST_INIT(&vg->vg_lvs);
952 
953 #define	VOL_FOREACH(func, tok, buf, p)					\
954 	while ((tok = strsep(buf, "\n")) != NULL) {			\
955 		if (strstr(tok, "{")) {					\
956 			func(buf, tok, p);				\
957 			continue;					\
958 		}							\
959 		if (strstr(tok, "}"))					\
960 			break;						\
961 	}
962 
963 	while ((tok = strsep(&buf, "\n")) != NULL) {
964 		if (strcmp(tok, "physical_volumes {") == 0) {
965 			VOL_FOREACH(llvm_textconf_decode_pv, tok, &buf, vg);
966 			continue;
967 		}
968 		if (strcmp(tok, "logical_volumes {") == 0) {
969 			VOL_FOREACH(llvm_textconf_decode_lv, tok, &buf, vg);
970 			continue;
971 		}
972 		if (strstr(tok, "{")) {
973 			G_LLVM_DEBUG(2, "unknown section %s", tok);
974 			continue;
975 		}
976 
977 		/* parse 'key = value' lines */
978 		if (strstr(tok, "=")) {
979 			SPLIT(v, tok, "=");
980 			GRAB_STR("id", v, tok, vg->vg_uuid, sizeof(vg->vg_uuid));
981 			GRAB_INT("extent_size", v, tok, vg->vg_extentsize);
982 			continue;
983 		}
984 	}
985 	/* basic checking */
986 	if (vg->vg_extentsize == 0)
987 		goto bad;
988 
989 	md->md_vg = vg;
990 	LIST_INSERT_HEAD(&vg_list, vg, vg_next);
991 	G_LLVM_DEBUG(3, "vg: name=%s uuid=%s", vg->vg_name, vg->vg_uuid);
992 	return(0);
993 
994 bad:
995 	g_llvm_free_vg(vg);
996 	return (-1);
997 }
998 #undef	VOL_FOREACH
999 
1000 static int
1001 llvm_textconf_decode_pv(char **buf, char *tok, struct g_llvm_vg *vg)
1002 {
1003 	struct g_llvm_pv	*pv;
1004 	char *v;
1005 	size_t len;
1006 
1007 	if (*buf == NULL || **buf == '\0')
1008 		return (EINVAL);
1009 
1010 	pv = malloc(sizeof(*pv), M_GLLVM, M_NOWAIT|M_ZERO);
1011 	if (pv == NULL)
1012 		return (ENOMEM);
1013 
1014 	pv->pv_vg = vg;
1015 	len = 0;
1016 	if (tok == NULL)
1017 		goto bad;
1018 	len = llvm_grab_name(pv->pv_name, tok);
1019 	if (len == 0)
1020 		goto bad;
1021 
1022 	while ((tok = strsep(buf, "\n")) != NULL) {
1023 		if (strstr(tok, "{"))
1024 			goto bad;
1025 
1026 		if (strstr(tok, "}"))
1027 			break;
1028 
1029 		/* parse 'key = value' lines */
1030 		if (strstr(tok, "=")) {
1031 			SPLIT(v, tok, "=");
1032 			GRAB_STR("id", v, tok, pv->pv_uuid, sizeof(pv->pv_uuid));
1033 			GRAB_INT("pe_start", v, tok, pv->pv_start);
1034 			GRAB_INT("pe_count", v, tok, pv->pv_count);
1035 			continue;
1036 		}
1037 	}
1038 	if (tok == NULL)
1039 		goto bad;
1040 	/* basic checking */
1041 	if (pv->pv_count == 0)
1042 		goto bad;
1043 
1044 	LIST_INSERT_HEAD(&vg->vg_pvs, pv, pv_next);
1045 	G_LLVM_DEBUG(3, "pv: name=%s uuid=%s", pv->pv_name, pv->pv_uuid);
1046 
1047 	return (0);
1048 bad:
1049 	free(pv, M_GLLVM);
1050 	return (-1);
1051 }
1052 
1053 static int
1054 llvm_textconf_decode_lv(char **buf, char *tok, struct g_llvm_vg *vg)
1055 {
1056 	struct g_llvm_lv	*lv;
1057 	struct g_llvm_segment *sg;
1058 	char *v;
1059 	size_t len;
1060 
1061 	if (*buf == NULL || **buf == '\0')
1062 		return (EINVAL);
1063 
1064 	lv = malloc(sizeof(*lv), M_GLLVM, M_NOWAIT|M_ZERO);
1065 	if (lv == NULL)
1066 		return (ENOMEM);
1067 
1068 	lv->lv_vg = vg;
1069 	LIST_INIT(&lv->lv_segs);
1070 
1071 	if (tok == NULL)
1072 		goto bad;
1073 	len = llvm_grab_name(lv->lv_name, tok);
1074 	if (len == 0)
1075 		goto bad;
1076 
1077 	while ((tok = strsep(buf, "\n")) != NULL) {
1078 		if (strstr(tok, "{")) {
1079 			if (strstr(tok, "segment")) {
1080 				llvm_textconf_decode_sg(buf, tok, lv);
1081 				continue;
1082 			} else
1083 				/* unexpected section */
1084 				goto bad;
1085 		}
1086 
1087 		if (strstr(tok, "}"))
1088 			break;
1089 
1090 		/* parse 'key = value' lines */
1091 		if (strstr(tok, "=")) {
1092 			SPLIT(v, tok, "=");
1093 			GRAB_STR("id", v, tok, lv->lv_uuid, sizeof(lv->lv_uuid));
1094 			GRAB_INT("segment_count", v, tok, lv->lv_sgcount);
1095 			continue;
1096 		}
1097 	}
1098 	if (tok == NULL)
1099 		goto bad;
1100 	if (lv->lv_sgcount == 0 || lv->lv_sgcount != lv->lv_numsegs)
1101 		/* zero or incomplete segment list */
1102 		goto bad;
1103 
1104 	/* Optimize for only one segment on the pv */
1105 	lv->lv_firstsg = LIST_FIRST(&lv->lv_segs);
1106 	LIST_INSERT_HEAD(&vg->vg_lvs, lv, lv_next);
1107 	G_LLVM_DEBUG(3, "lv: name=%s uuid=%s", lv->lv_name, lv->lv_uuid);
1108 
1109 	return (0);
1110 bad:
1111 	while ((sg = LIST_FIRST(&lv->lv_segs)) != NULL) {
1112 		LIST_REMOVE(sg, sg_next);
1113 		free(sg, M_GLLVM);
1114 	}
1115 	free(lv, M_GLLVM);
1116 	return (-1);
1117 }
1118 
1119 static int
1120 llvm_textconf_decode_sg(char **buf, char *tok, struct g_llvm_lv *lv)
1121 {
1122 	struct g_llvm_segment *sg;
1123 	char *v;
1124 	int count = 0;
1125 
1126 	if (*buf == NULL || **buf == '\0')
1127 		return (EINVAL);
1128 
1129 	sg = malloc(sizeof(*sg), M_GLLVM, M_NOWAIT|M_ZERO);
1130 	if (sg == NULL)
1131 		return (ENOMEM);
1132 
1133 	while ((tok = strsep(buf, "\n")) != NULL) {
1134 		/* only a single linear stripe is supported */
1135 		if (strstr(tok, "stripe_count")) {
1136 			SPLIT(v, tok, "=");
1137 			GRAB_INT("stripe_count", v, tok, count);
1138 			if (count != 1)
1139 				goto bad;
1140 		}
1141 
1142 		if (strstr(tok, "{"))
1143 			goto bad;
1144 
1145 		if (strstr(tok, "}"))
1146 			break;
1147 
1148 		if (strcmp(tok, "stripes = [") == 0) {
1149 			tok = strsep(buf, "\n");
1150 			if (tok == NULL)
1151 				goto bad;
1152 
1153 			strsep(&tok, "\"");
1154 			if (tok == NULL)
1155 				goto bad;	/* missing open quotes */
1156 			v = strsep(&tok, "\"");
1157 			if (tok == NULL)
1158 				goto bad;	/* missing close quotes */
1159 			strncpy(sg->sg_pvname, v, sizeof(sg->sg_pvname));
1160 			if (*tok != ',')
1161 				goto bad;	/* missing comma for stripe */
1162 			tok++;
1163 
1164 			sg->sg_pvstart = strtol(tok, &v, 10);
1165 			if (v == tok)
1166 				/* strtol did not eat any of the buffer */
1167 				goto bad;
1168 
1169 			continue;
1170 		}
1171 
1172 		/* parse 'key = value' lines */
1173 		if (strstr(tok, "=")) {
1174 			SPLIT(v, tok, "=");
1175 			GRAB_INT("start_extent", v, tok, sg->sg_start);
1176 			GRAB_INT("extent_count", v, tok, sg->sg_count);
1177 			continue;
1178 		}
1179 	}
1180 	if (tok == NULL)
1181 		goto bad;
1182 	/* basic checking */
1183 	if (count != 1 || sg->sg_count == 0)
1184 		goto bad;
1185 
1186 	sg->sg_end = sg->sg_start + sg->sg_count - 1;
1187 	lv->lv_numsegs++;
1188 	lv->lv_extentcount += sg->sg_count;
1189 	LIST_INSERT_HEAD(&lv->lv_segs, sg, sg_next);
1190 
1191 	return (0);
1192 bad:
1193 	free(sg, M_GLLVM);
1194 	return (-1);
1195 }
1196 #undef	GRAB_INT
1197 #undef	GRAB_STR
1198 #undef	SPLIT
1199 
1200 static struct g_class g_llvm_class = {
1201 	.name = G_LLVM_CLASS_NAME,
1202 	.version = G_VERSION,
1203 	.init = g_llvm_init,
1204 	.taste = g_llvm_taste,
1205 	.destroy_geom = g_llvm_destroy_geom
1206 };
1207 
1208 DECLARE_GEOM_CLASS(g_llvm_class, g_linux_lvm);
1209 MODULE_VERSION(geom_linux_lvm, 0);
1210