xref: /freebsd/sys/geom/linux_lvm/g_linux_lvm.c (revision 0edc114ac0b998b06235da32bec24d55c10206cd)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 __FBSDID("$FreeBSD$");
31 
32 #include <sys/ctype.h>
33 #include <sys/param.h>
34 #include <sys/bio.h>
35 #include <sys/kernel.h>
36 #include <sys/limits.h>
37 #include <sys/malloc.h>
38 #include <sys/queue.h>
39 #include <sys/sysctl.h>
40 #include <sys/systm.h>
41 
42 #include <geom/geom.h>
43 #include <geom/geom_dbg.h>
44 #include <sys/endian.h>
45 
46 #include <geom/linux_lvm/g_linux_lvm.h>
47 
48 FEATURE(geom_linux_lvm, "GEOM Linux LVM partitioning support");
49 
50 /* Declare malloc(9) label */
51 static MALLOC_DEFINE(M_GLLVM, "gllvm", "GEOM_LINUX_LVM Data");
52 
53 /* GEOM class methods */
54 static g_access_t g_llvm_access;
55 static g_init_t g_llvm_init;
56 static g_orphan_t g_llvm_orphan;
57 static g_orphan_t g_llvm_taste_orphan;
58 static g_start_t g_llvm_start;
59 static g_taste_t g_llvm_taste;
60 static g_ctl_destroy_geom_t g_llvm_destroy_geom;
61 
62 static void	g_llvm_done(struct bio *);
63 static void	g_llvm_remove_disk(struct g_llvm_vg *, struct g_consumer *);
64 static int	g_llvm_activate_lv(struct g_llvm_vg *, struct g_llvm_lv *);
65 static int	g_llvm_add_disk(struct g_llvm_vg *, struct g_provider *, char *);
66 static void	g_llvm_free_vg(struct g_llvm_vg *);
67 static int	g_llvm_destroy(struct g_llvm_vg *, int);
68 static int	g_llvm_read_label(struct g_consumer *, struct g_llvm_label *);
69 static int	g_llvm_read_md(struct g_consumer *, struct g_llvm_metadata *,
70 		    struct g_llvm_label *);
71 
72 static int	llvm_label_decode(const u_char *, struct g_llvm_label *, int);
73 static int	llvm_md_decode(const u_char *, struct g_llvm_metadata *,
74 		    struct g_llvm_label *);
75 static int	llvm_textconf_decode(u_char *, int,
76 		    struct g_llvm_metadata *);
77 static int	llvm_textconf_decode_pv(char **, char *, struct g_llvm_vg *);
78 static int	llvm_textconf_decode_lv(char **, char *, struct g_llvm_vg *);
79 static int	llvm_textconf_decode_sg(char **, char *, struct g_llvm_lv *);
80 
81 SYSCTL_DECL(_kern_geom);
82 SYSCTL_NODE(_kern_geom, OID_AUTO, linux_lvm, CTLFLAG_RW, 0,
83     "GEOM_LINUX_LVM stuff");
84 static u_int g_llvm_debug = 0;
85 SYSCTL_UINT(_kern_geom_linux_lvm, OID_AUTO, debug, CTLFLAG_RWTUN, &g_llvm_debug, 0,
86     "Debug level");
87 
88 LIST_HEAD(, g_llvm_vg) vg_list;
89 
90 /*
91  * Called to notify geom when it's been opened, and for what intent
92  */
93 static int
94 g_llvm_access(struct g_provider *pp, int dr, int dw, int de)
95 {
96 	struct g_consumer *c;
97 	struct g_llvm_vg *vg;
98 	struct g_geom *gp;
99 	int error;
100 
101 	KASSERT(pp != NULL, ("%s: NULL provider", __func__));
102 	gp = pp->geom;
103 	KASSERT(gp != NULL, ("%s: NULL geom", __func__));
104 	vg = gp->softc;
105 
106 	if (vg == NULL) {
107 		/* It seems that .access can be called with negative dr,dw,dx
108 		 * in this case but I want to check for myself */
109 		G_LLVM_DEBUG(0, "access(%d, %d, %d) for %s",
110 		    dr, dw, de, pp->name);
111 
112 		/* This should only happen when geom is withered so
113 		 * allow only negative requests */
114 		KASSERT(dr <= 0 && dw <= 0 && de <= 0,
115 		    ("%s: Positive access for %s", __func__, pp->name));
116 		if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0)
117 			G_LLVM_DEBUG(0,
118 			    "Device %s definitely destroyed", pp->name);
119 		return (0);
120 	}
121 
122 	/* Grab an exclusive bit to propagate on our consumers on first open */
123 	if (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)
124 		de++;
125 	/* ... drop it on close */
126 	if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0)
127 		de--;
128 
129 	error = ENXIO;
130 	LIST_FOREACH(c, &gp->consumer, consumer) {
131 		KASSERT(c != NULL, ("%s: consumer is NULL", __func__));
132 		error = g_access(c, dr, dw, de);
133 		if (error != 0) {
134 			struct g_consumer *c2;
135 
136 			/* Backout earlier changes */
137 			LIST_FOREACH(c2, &gp->consumer, consumer) {
138 				if (c2 == c) /* all eariler components fixed */
139 					return (error);
140 				g_access(c2, -dr, -dw, -de);
141 			}
142 		}
143 	}
144 
145 	return (error);
146 }
147 
148 /*
149  * Dismantle bio_queue and destroy its components
150  */
151 static void
152 bioq_dismantle(struct bio_queue_head *bq)
153 {
154 	struct bio *b;
155 
156 	for (b = bioq_first(bq); b != NULL; b = bioq_first(bq)) {
157 		bioq_remove(bq, b);
158 		g_destroy_bio(b);
159 	}
160 }
161 
162 /*
163  * GEOM .done handler
164  * Can't use standard handler because one requested IO may
165  * fork into additional data IOs
166  */
167 static void
168 g_llvm_done(struct bio *b)
169 {
170 	struct bio *parent_b;
171 
172 	parent_b = b->bio_parent;
173 
174 	if (b->bio_error != 0) {
175 		G_LLVM_DEBUG(0, "Error %d for offset=%ju, length=%ju on %s",
176 		    b->bio_error, b->bio_offset, b->bio_length,
177 		    b->bio_to->name);
178 		if (parent_b->bio_error == 0)
179 			parent_b->bio_error = b->bio_error;
180 	}
181 
182 	parent_b->bio_inbed++;
183 	parent_b->bio_completed += b->bio_completed;
184 
185 	if (parent_b->bio_children == parent_b->bio_inbed) {
186 		parent_b->bio_completed = parent_b->bio_length;
187 		g_io_deliver(parent_b, parent_b->bio_error);
188 	}
189 	g_destroy_bio(b);
190 }
191 
192 static void
193 g_llvm_start(struct bio *bp)
194 {
195 	struct g_provider *pp;
196 	struct g_llvm_vg *vg;
197 	struct g_llvm_pv *pv;
198 	struct g_llvm_lv *lv;
199 	struct g_llvm_segment *sg;
200 	struct bio *cb;
201 	struct bio_queue_head bq;
202 	size_t chunk_size;
203 	off_t offset, length;
204 	char *addr;
205 	u_int count;
206 
207 	pp = bp->bio_to;
208 	lv = pp->private;
209 	vg = pp->geom->softc;
210 
211 	switch (bp->bio_cmd) {
212 	case BIO_READ:
213 	case BIO_WRITE:
214 	case BIO_DELETE:
215 	/* XXX BIO_GETATTR allowed? */
216 		break;
217 	default:
218 		g_io_deliver(bp, EOPNOTSUPP);
219 		return;
220 	}
221 
222 	bioq_init(&bq);
223 
224 	chunk_size = vg->vg_extentsize;
225 	addr = bp->bio_data;
226 	offset = bp->bio_offset;	/* virtual offset and length */
227 	length = bp->bio_length;
228 
229 	while (length > 0) {
230 		size_t chunk_index, in_chunk_offset, in_chunk_length;
231 
232 		pv = NULL;
233 		cb = g_clone_bio(bp);
234 		if (cb == NULL) {
235 			bioq_dismantle(&bq);
236 			if (bp->bio_error == 0)
237 				bp->bio_error = ENOMEM;
238 			g_io_deliver(bp, bp->bio_error);
239 			return;
240 		}
241 
242 		/* get the segment and the pv */
243 		if (lv->lv_sgcount == 1) {
244 			/* skip much of the calculations for a single sg */
245 			chunk_index = 0;
246 			in_chunk_offset = 0;
247 			in_chunk_length = length;
248 			sg = lv->lv_firstsg;
249 			pv = sg->sg_pv;
250 			cb->bio_offset = offset + sg->sg_pvoffset;
251 		} else {
252 			chunk_index = offset / chunk_size; /* round downwards */
253 			in_chunk_offset = offset % chunk_size;
254 			in_chunk_length =
255 			    min(length, chunk_size - in_chunk_offset);
256 
257 			/* XXX could be faster */
258 			LIST_FOREACH(sg, &lv->lv_segs, sg_next) {
259 				if (chunk_index >= sg->sg_start &&
260 				    chunk_index <= sg->sg_end) {
261 					/* adjust chunk index for sg start */
262 					chunk_index -= sg->sg_start;
263 					pv = sg->sg_pv;
264 					break;
265 				}
266 			}
267 			cb->bio_offset =
268 			    (off_t)chunk_index * (off_t)chunk_size
269 			    + in_chunk_offset + sg->sg_pvoffset;
270 		}
271 
272 		KASSERT(pv != NULL, ("Can't find PV for chunk %zu",
273 		    chunk_index));
274 
275 		cb->bio_to = pv->pv_gprov;
276 		cb->bio_done = g_llvm_done;
277 		cb->bio_length = in_chunk_length;
278 		cb->bio_data = addr;
279 		cb->bio_caller1 = pv;
280 		bioq_disksort(&bq, cb);
281 
282 		G_LLVM_DEBUG(5,
283 		    "Mapped %s(%ju, %ju) on %s to %zu(%zu,%zu) @ %s:%ju",
284 		    bp->bio_cmd == BIO_READ ? "R" : "W",
285 		    offset, length, lv->lv_name,
286 		    chunk_index, in_chunk_offset, in_chunk_length,
287 		    pv->pv_name, cb->bio_offset);
288 
289 		addr += in_chunk_length;
290 		length -= in_chunk_length;
291 		offset += in_chunk_length;
292 	}
293 
294 	/* Fire off bio's here */
295 	count = 0;
296 	for (cb = bioq_first(&bq); cb != NULL; cb = bioq_first(&bq)) {
297 		bioq_remove(&bq, cb);
298 		pv = cb->bio_caller1;
299 		cb->bio_caller1 = NULL;
300 		G_LLVM_DEBUG(6, "firing bio to %s, offset=%ju, length=%ju",
301 		    cb->bio_to->name, cb->bio_offset, cb->bio_length);
302 		g_io_request(cb, pv->pv_gcons);
303 		count++;
304 	}
305 	if (count == 0) { /* We handled everything locally */
306 		bp->bio_completed = bp->bio_length;
307 		g_io_deliver(bp, 0);
308 	}
309 }
310 
311 static void
312 g_llvm_remove_disk(struct g_llvm_vg *vg, struct g_consumer *cp)
313 {
314 	struct g_llvm_pv *pv;
315 	struct g_llvm_lv *lv;
316 	struct g_llvm_segment *sg;
317 	int found;
318 
319 	KASSERT(cp != NULL, ("Non-valid disk in %s.", __func__));
320 	pv = (struct g_llvm_pv *)cp->private;
321 
322 	G_LLVM_DEBUG(0, "Disk %s removed from %s.", cp->provider->name,
323 	    pv->pv_name);
324 
325 	LIST_FOREACH(lv, &vg->vg_lvs, lv_next) {
326 		/* Find segments that map to this disk */
327 		found = 0;
328 		LIST_FOREACH(sg, &lv->lv_segs, sg_next) {
329 			if (sg->sg_pv == pv) {
330 				sg->sg_pv = NULL;
331 				lv->lv_sgactive--;
332 				found = 1;
333 				break;
334 			}
335 		}
336 		if (found) {
337 			G_LLVM_DEBUG(0, "Device %s removed.",
338 			    lv->lv_gprov->name);
339 			g_wither_provider(lv->lv_gprov, ENXIO);
340 			lv->lv_gprov = NULL;
341 		}
342 	}
343 
344 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
345 		g_access(cp, -cp->acr, -cp->acw, -cp->ace);
346 	g_detach(cp);
347 	g_destroy_consumer(cp);
348 }
349 
350 static void
351 g_llvm_orphan(struct g_consumer *cp)
352 {
353 	struct g_llvm_vg *vg;
354 	struct g_geom *gp;
355 
356 	g_topology_assert();
357 	gp = cp->geom;
358 	vg = gp->softc;
359 	if (vg == NULL)
360 		return;
361 
362 	g_llvm_remove_disk(vg, cp);
363 	g_llvm_destroy(vg, 1);
364 }
365 
366 static int
367 g_llvm_activate_lv(struct g_llvm_vg *vg, struct g_llvm_lv *lv)
368 {
369 	struct g_geom *gp;
370 	struct g_provider *pp;
371 
372 	g_topology_assert();
373 
374 	KASSERT(lv->lv_sgactive == lv->lv_sgcount, ("segment missing"));
375 
376 	gp = vg->vg_geom;
377 	pp = g_new_providerf(gp, "linux_lvm/%s-%s", vg->vg_name, lv->lv_name);
378 	pp->mediasize = vg->vg_extentsize * (off_t)lv->lv_extentcount;
379 	pp->sectorsize = vg->vg_sectorsize;
380 	g_error_provider(pp, 0);
381 	lv->lv_gprov = pp;
382 	pp->private = lv;
383 
384 	G_LLVM_DEBUG(1, "Created %s, %juM", pp->name,
385 	    pp->mediasize / (1024*1024));
386 
387 	return (0);
388 }
389 
390 static int
391 g_llvm_add_disk(struct g_llvm_vg *vg, struct g_provider *pp, char *uuid)
392 {
393 	struct g_geom *gp;
394 	struct g_consumer *cp, *fcp;
395 	struct g_llvm_pv *pv;
396 	struct g_llvm_lv *lv;
397 	struct g_llvm_segment *sg;
398 	int error;
399 
400 	g_topology_assert();
401 
402 	LIST_FOREACH(pv, &vg->vg_pvs, pv_next) {
403 		if (strcmp(pv->pv_uuid, uuid) == 0)
404 			break;	/* found it */
405 	}
406 	if (pv == NULL) {
407 		G_LLVM_DEBUG(3, "uuid %s not found in pv list", uuid);
408 		return (ENOENT);
409 	}
410 	if (pv->pv_gprov != NULL) {
411 		G_LLVM_DEBUG(0, "disk %s already initialised in %s",
412 		    pv->pv_name, vg->vg_name);
413 		return (EEXIST);
414 	}
415 
416 	pv->pv_start *= vg->vg_sectorsize;
417 	gp = vg->vg_geom;
418 	fcp = LIST_FIRST(&gp->consumer);
419 
420 	cp = g_new_consumer(gp);
421 	error = g_attach(cp, pp);
422 	G_LLVM_DEBUG(1, "Attached %s to %s at offset %ju",
423 	    pp->name, pv->pv_name, pv->pv_start);
424 
425 	if (error != 0) {
426 		G_LLVM_DEBUG(0, "cannot attach %s to %s",
427 		    pp->name, vg->vg_name);
428 		g_destroy_consumer(cp);
429 		return (error);
430 	}
431 
432 	if (fcp != NULL) {
433 		if (fcp->provider->sectorsize != pp->sectorsize) {
434 			G_LLVM_DEBUG(0, "Provider %s of %s has invalid "
435 			    "sector size (%d)", pp->name, vg->vg_name,
436 			    pp->sectorsize);
437 			return (EINVAL);
438 		}
439 		if (fcp->acr > 0 || fcp->acw || fcp->ace > 0) {
440 			/* Replicate access permissions from first "live"
441 			 * consumer to the new one */
442 			error = g_access(cp, fcp->acr, fcp->acw, fcp->ace);
443 			if (error != 0) {
444 				g_detach(cp);
445 				g_destroy_consumer(cp);
446 				return (error);
447 			}
448 		}
449 	}
450 
451 	cp->private = pv;
452 	pv->pv_gcons = cp;
453 	pv->pv_gprov = pp;
454 
455 	LIST_FOREACH(lv, &vg->vg_lvs, lv_next) {
456 		/* Find segments that map to this disk */
457 		LIST_FOREACH(sg, &lv->lv_segs, sg_next) {
458 			if (strcmp(sg->sg_pvname, pv->pv_name) == 0) {
459 				/* avtivate the segment */
460 				KASSERT(sg->sg_pv == NULL,
461 				    ("segment already mapped"));
462 				sg->sg_pvoffset =
463 				    (off_t)sg->sg_pvstart * vg->vg_extentsize
464 				    + pv->pv_start;
465 				sg->sg_pv = pv;
466 				lv->lv_sgactive++;
467 
468 				G_LLVM_DEBUG(2, "%s: %d to %d @ %s:%d"
469 				    " offset %ju sector %ju",
470 				    lv->lv_name, sg->sg_start, sg->sg_end,
471 				    sg->sg_pvname, sg->sg_pvstart,
472 				    sg->sg_pvoffset,
473 				    sg->sg_pvoffset / vg->vg_sectorsize);
474 			}
475 		}
476 		/* Activate any lvs waiting on this disk */
477 		if (lv->lv_gprov == NULL && lv->lv_sgactive == lv->lv_sgcount) {
478 			error = g_llvm_activate_lv(vg, lv);
479 			if (error)
480 				break;
481 		}
482 	}
483 	return (error);
484 }
485 
486 static void
487 g_llvm_init(struct g_class *mp)
488 {
489 	LIST_INIT(&vg_list);
490 }
491 
492 static void
493 g_llvm_free_vg(struct g_llvm_vg *vg)
494 {
495 	struct g_llvm_pv *pv;
496 	struct g_llvm_lv *lv;
497 	struct g_llvm_segment *sg;
498 
499 	/* Free all the structures */
500 	while ((pv = LIST_FIRST(&vg->vg_pvs)) != NULL) {
501 		LIST_REMOVE(pv, pv_next);
502 		free(pv, M_GLLVM);
503 	}
504 	while ((lv = LIST_FIRST(&vg->vg_lvs)) != NULL) {
505 		while ((sg = LIST_FIRST(&lv->lv_segs)) != NULL) {
506 			LIST_REMOVE(sg, sg_next);
507 			free(sg, M_GLLVM);
508 		}
509 		LIST_REMOVE(lv, lv_next);
510 		free(lv, M_GLLVM);
511 	}
512 	LIST_REMOVE(vg, vg_next);
513 	free(vg, M_GLLVM);
514 }
515 
516 static void
517 g_llvm_taste_orphan(struct g_consumer *cp)
518 {
519 
520 	KASSERT(1 == 0, ("%s called while tasting %s.", __func__,
521 	    cp->provider->name));
522 }
523 
524 static struct g_geom *
525 g_llvm_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
526 {
527 	struct g_consumer *cp;
528 	struct g_geom *gp;
529 	struct g_llvm_label ll;
530 	struct g_llvm_metadata md;
531 	struct g_llvm_vg *vg;
532 	int error;
533 
534 	bzero(&md, sizeof(md));
535 
536 	g_topology_assert();
537 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
538 	gp = g_new_geomf(mp, "linux_lvm:taste");
539 	/* This orphan function should be never called. */
540 	gp->orphan = g_llvm_taste_orphan;
541 	cp = g_new_consumer(gp);
542 	g_attach(cp, pp);
543 	error = g_llvm_read_label(cp, &ll);
544 	if (!error)
545 		error = g_llvm_read_md(cp, &md, &ll);
546 	g_detach(cp);
547 	g_destroy_consumer(cp);
548 	g_destroy_geom(gp);
549 	if (error != 0)
550 		return (NULL);
551 
552 	vg = md.md_vg;
553 	if (vg->vg_geom == NULL) {
554 		/* new volume group */
555 		gp = g_new_geomf(mp, "%s", vg->vg_name);
556 		gp->start = g_llvm_start;
557 		gp->spoiled = g_llvm_orphan;
558 		gp->orphan = g_llvm_orphan;
559 		gp->access = g_llvm_access;
560 		vg->vg_sectorsize = pp->sectorsize;
561 		vg->vg_extentsize *= vg->vg_sectorsize;
562 		vg->vg_geom = gp;
563 		gp->softc = vg;
564 		G_LLVM_DEBUG(1, "Created volume %s, extent size %zuK",
565 		    vg->vg_name, vg->vg_extentsize / 1024);
566 	}
567 
568 	/* initialise this disk in the volume group */
569 	g_llvm_add_disk(vg, pp, ll.ll_uuid);
570 	return (vg->vg_geom);
571 }
572 
573 static int
574 g_llvm_destroy(struct g_llvm_vg *vg, int force)
575 {
576 	struct g_provider *pp;
577 	struct g_geom *gp;
578 
579 	g_topology_assert();
580 	if (vg == NULL)
581 		return (ENXIO);
582 	gp = vg->vg_geom;
583 
584 	LIST_FOREACH(pp, &gp->provider, provider) {
585 		if (pp->acr != 0 || pp->acw != 0 || pp->ace != 0) {
586 			G_LLVM_DEBUG(1, "Device %s is still open (r%dw%de%d)",
587 			    pp->name, pp->acr, pp->acw, pp->ace);
588 			if (!force)
589 				return (EBUSY);
590 		}
591 	}
592 
593 	g_llvm_free_vg(gp->softc);
594 	gp->softc = NULL;
595 	g_wither_geom(gp, ENXIO);
596 	return (0);
597 }
598 
599 static int
600 g_llvm_destroy_geom(struct gctl_req *req __unused, struct g_class *mp __unused,
601     struct g_geom *gp)
602 {
603 	struct g_llvm_vg *vg;
604 
605 	vg = gp->softc;
606 	return (g_llvm_destroy(vg, 0));
607 }
608 
609 int
610 g_llvm_read_label(struct g_consumer *cp, struct g_llvm_label *ll)
611 {
612 	struct g_provider *pp;
613 	u_char *buf;
614 	int i, error = 0;
615 
616 	g_topology_assert();
617 
618 	/* The LVM label is stored on the first four sectors */
619 	error = g_access(cp, 1, 0, 0);
620 	if (error != 0)
621 		return (error);
622 	pp = cp->provider;
623 	g_topology_unlock();
624 	buf = g_read_data(cp, 0, pp->sectorsize * 4, &error);
625 	g_topology_lock();
626 	g_access(cp, -1, 0, 0);
627 	if (buf == NULL) {
628 		G_LLVM_DEBUG(1, "Cannot read metadata from %s (error=%d)",
629 		    pp->name, error);
630 		return (error);
631 	}
632 
633 	/* Search the four sectors for the LVM label. */
634 	for (i = 0; i < 4; i++) {
635 		error = llvm_label_decode(&buf[i * pp->sectorsize], ll, i);
636 		if (error == 0)
637 			break;	/* found it */
638 	}
639 	g_free(buf);
640 	return (error);
641 }
642 
643 int
644 g_llvm_read_md(struct g_consumer *cp, struct g_llvm_metadata *md,
645     struct g_llvm_label *ll)
646 {
647 	struct g_provider *pp;
648 	u_char *buf;
649 	int error;
650 	int size;
651 
652 	g_topology_assert();
653 
654 	error = g_access(cp, 1, 0, 0);
655 	if (error != 0)
656 		return (error);
657 	pp = cp->provider;
658 	g_topology_unlock();
659 	buf = g_read_data(cp, ll->ll_md_offset, pp->sectorsize, &error);
660 	g_topology_lock();
661 	g_access(cp, -1, 0, 0);
662 	if (buf == NULL) {
663 		G_LLVM_DEBUG(0, "Cannot read metadata from %s (error=%d)",
664 		    cp->provider->name, error);
665 		return (error);
666 	}
667 
668 	error = llvm_md_decode(buf, md, ll);
669 	g_free(buf);
670 	if (error != 0) {
671 		return (error);
672 	}
673 
674 	G_LLVM_DEBUG(1, "reading LVM2 config @ %s:%ju", pp->name,
675 		    ll->ll_md_offset + md->md_reloffset);
676 	error = g_access(cp, 1, 0, 0);
677 	if (error != 0)
678 		return (error);
679 	pp = cp->provider;
680 	g_topology_unlock();
681 	/* round up to the nearest sector */
682 	size = md->md_relsize +
683 	    (pp->sectorsize - md->md_relsize % pp->sectorsize);
684 	buf = g_read_data(cp, ll->ll_md_offset + md->md_reloffset, size, &error);
685 	g_topology_lock();
686 	g_access(cp, -1, 0, 0);
687 	if (buf == NULL) {
688 		G_LLVM_DEBUG(0, "Cannot read LVM2 config from %s (error=%d)",
689 		    pp->name, error);
690 		return (error);
691 	}
692 	buf[md->md_relsize] = '\0';
693 	G_LLVM_DEBUG(10, "LVM config:\n%s\n", buf);
694 	error = llvm_textconf_decode(buf, md->md_relsize, md);
695 	g_free(buf);
696 
697 	return (error);
698 }
699 
700 static int
701 llvm_label_decode(const u_char *data, struct g_llvm_label *ll, int sector)
702 {
703 	uint64_t off;
704 	char *uuid;
705 
706 	/* Magic string */
707 	if (bcmp("LABELONE", data , 8) != 0)
708 		return (EINVAL);
709 
710 	/* We only support LVM2 text format */
711 	if (bcmp("LVM2 001", data + 24, 8) != 0) {
712 		G_LLVM_DEBUG(0, "Unsupported LVM format");
713 		return (EINVAL);
714 	}
715 
716 	ll->ll_sector = le64dec(data + 8);
717 	ll->ll_crc = le32dec(data + 16);
718 	ll->ll_offset = le32dec(data + 20);
719 
720 	if (ll->ll_sector != sector) {
721 		G_LLVM_DEBUG(0, "Expected sector %ju, found at %d",
722 		    ll->ll_sector, sector);
723 		return (EINVAL);
724 	}
725 
726 	off = ll->ll_offset;
727 	/*
728 	 * convert the binary uuid to string format, the format is
729 	 * xxxxxx-xxxx-xxxx-xxxx-xxxx-xxxx-xxxxxx (6-4-4-4-4-4-6)
730 	 */
731 	uuid = ll->ll_uuid;
732 	bcopy(data + off, uuid, 6);
733 	off += 6;
734 	uuid += 6;
735 	*uuid++ = '-';
736 	for (int i = 0; i < 5; i++) {
737 		bcopy(data + off, uuid, 4);
738 		off += 4;
739 		uuid += 4;
740 		*uuid++ = '-';
741 	}
742 	bcopy(data + off, uuid, 6);
743 	off += 6;
744 	uuid += 6;
745 	*uuid++ = '\0';
746 
747 	ll->ll_size = le64dec(data + off);
748 	off += 8;
749 	ll->ll_pestart = le64dec(data + off);
750 	off += 16;
751 
752 	/* Only one data section is supported */
753 	if (le64dec(data + off) != 0) {
754 		G_LLVM_DEBUG(0, "Only one data section supported");
755 		return (EINVAL);
756 	}
757 
758 	off += 16;
759 	ll->ll_md_offset = le64dec(data + off);
760 	off += 8;
761 	ll->ll_md_size = le64dec(data + off);
762 	off += 8;
763 
764 	G_LLVM_DEBUG(1, "LVM metadata: offset=%ju, size=%ju", ll->ll_md_offset,
765 	    ll->ll_md_size);
766 
767 	/* Only one data section is supported */
768 	if (le64dec(data + off) != 0) {
769 		G_LLVM_DEBUG(0, "Only one metadata section supported");
770 		return (EINVAL);
771 	}
772 
773 	G_LLVM_DEBUG(2, "label uuid=%s", ll->ll_uuid);
774 	G_LLVM_DEBUG(2, "sector=%ju, crc=%u, offset=%u, size=%ju, pestart=%ju",
775 	    ll->ll_sector, ll->ll_crc, ll->ll_offset, ll->ll_size,
776 	    ll->ll_pestart);
777 
778 	return (0);
779 }
780 
781 static int
782 llvm_md_decode(const u_char *data, struct g_llvm_metadata *md,
783     struct g_llvm_label *ll)
784 {
785 	uint64_t off;
786 	char magic[16];
787 
788 	off = 0;
789 	md->md_csum = le32dec(data + off);
790 	off += 4;
791 	bcopy(data + off, magic, 16);
792 	off += 16;
793 	md->md_version = le32dec(data + off);
794 	off += 4;
795 	md->md_start = le64dec(data + off);
796 	off += 8;
797 	md->md_size = le64dec(data + off);
798 	off += 8;
799 
800 	if (bcmp(G_LLVM_MAGIC, magic, 16) != 0) {
801 		G_LLVM_DEBUG(0, "Incorrect md magic number");
802 		return (EINVAL);
803 	}
804 	if (md->md_version != 1) {
805 		G_LLVM_DEBUG(0, "Incorrect md version number (%u)",
806 		    md->md_version);
807 		return (EINVAL);
808 	}
809 	if (md->md_start != ll->ll_md_offset) {
810 		G_LLVM_DEBUG(0, "Incorrect md offset (%ju)", md->md_start);
811 		return (EINVAL);
812 	}
813 
814 	/* Aparently only one is ever returned */
815 	md->md_reloffset = le64dec(data + off);
816 	off += 8;
817 	md->md_relsize = le64dec(data + off);
818 	off += 16;	/* XXX skipped checksum */
819 
820 	if (le64dec(data + off) != 0) {
821 		G_LLVM_DEBUG(0, "Only one reloc supported");
822 		return (EINVAL);
823 	}
824 
825 	G_LLVM_DEBUG(3, "reloc: offset=%ju, size=%ju",
826 	    md->md_reloffset, md->md_relsize);
827 	G_LLVM_DEBUG(3, "md: version=%u, start=%ju, size=%ju",
828 	    md->md_version, md->md_start, md->md_size);
829 
830 	return (0);
831 }
832 
833 #define	GRAB_INT(key, tok1, tok2, v)					\
834 	if (tok1 && tok2 && strncmp(tok1, key, sizeof(key)) == 0) {	\
835 		v = strtol(tok2, &tok1, 10);				\
836 		if (tok1 == tok2)					\
837 			/* strtol did not eat any of the buffer */	\
838 			goto bad;					\
839 		continue;						\
840 	}
841 
842 #define	GRAB_STR(key, tok1, tok2, v, len)				\
843 	if (tok1 && tok2 && strncmp(tok1, key, sizeof(key)) == 0) {	\
844 		strsep(&tok2, "\"");					\
845 		if (tok2 == NULL)					\
846 			continue;					\
847 		tok1 = strsep(&tok2, "\"");				\
848 		if (tok2 == NULL)					\
849 			continue;					\
850 		strncpy(v, tok1, len);					\
851 		continue;						\
852 	}
853 
854 #define	SPLIT(key, value, str)						\
855 	key = strsep(&value, str);					\
856 	/* strip trailing whitespace on the key */			\
857 	for (char *t = key; *t != '\0'; t++)				\
858 		if (isspace(*t)) {					\
859 			*t = '\0';					\
860 			break;						\
861 		}
862 
863 static size_t
864 llvm_grab_name(char *name, const char *tok)
865 {
866 	size_t len;
867 
868 	len = 0;
869 	if (tok == NULL)
870 		return (0);
871 	if (tok[0] == '-')
872 		return (0);
873 	if (strcmp(tok, ".") == 0 || strcmp(tok, "..") == 0)
874 		return (0);
875 	while (tok[len] && (isalpha(tok[len]) || isdigit(tok[len]) ||
876 	    tok[len] == '.' || tok[len] == '_' || tok[len] == '-' ||
877 	    tok[len] == '+') && len < G_LLVM_NAMELEN - 1)
878 		len++;
879 	bcopy(tok, name, len);
880 	name[len] = '\0';
881 	return (len);
882 }
883 
884 static int
885 llvm_textconf_decode(u_char *data, int buflen, struct g_llvm_metadata *md)
886 {
887 	struct g_llvm_vg	*vg;
888 	char *buf = data;
889 	char *tok, *v;
890 	char name[G_LLVM_NAMELEN];
891 	char uuid[G_LLVM_UUIDLEN];
892 	size_t len;
893 
894 	if (buf == NULL || *buf == '\0')
895 		return (EINVAL);
896 
897 	tok = strsep(&buf, "\n");
898 	if (tok == NULL)
899 		return (EINVAL);
900 	len = llvm_grab_name(name, tok);
901 	if (len == 0)
902 		return (EINVAL);
903 
904 	/* check too see if the vg has already been loaded off another disk */
905 	LIST_FOREACH(vg, &vg_list, vg_next) {
906 		if (strcmp(vg->vg_name, name) == 0) {
907 			uuid[0] = '\0';
908 			/* grab the volume group uuid */
909 			while ((tok = strsep(&buf, "\n")) != NULL) {
910 				if (strstr(tok, "{"))
911 					break;
912 				if (strstr(tok, "=")) {
913 					SPLIT(v, tok, "=");
914 					GRAB_STR("id", v, tok, uuid,
915 					    sizeof(uuid));
916 				}
917 			}
918 			if (strcmp(vg->vg_uuid, uuid) == 0) {
919 				/* existing vg */
920 				md->md_vg = vg;
921 				return (0);
922 			}
923 			/* XXX different volume group with name clash! */
924 			G_LLVM_DEBUG(0,
925 			    "%s already exists, volume group not loaded", name);
926 			return (EINVAL);
927 		}
928 	}
929 
930 	vg = malloc(sizeof(*vg), M_GLLVM, M_NOWAIT|M_ZERO);
931 	if (vg == NULL)
932 		return (ENOMEM);
933 
934 	strncpy(vg->vg_name, name, sizeof(vg->vg_name));
935 	LIST_INIT(&vg->vg_pvs);
936 	LIST_INIT(&vg->vg_lvs);
937 
938 #define	VOL_FOREACH(func, tok, buf, p)					\
939 	while ((tok = strsep(buf, "\n")) != NULL) {			\
940 		if (strstr(tok, "{")) {					\
941 			func(buf, tok, p);				\
942 			continue;					\
943 		}							\
944 		if (strstr(tok, "}"))					\
945 			break;						\
946 	}
947 
948 	while ((tok = strsep(&buf, "\n")) != NULL) {
949 		if (strcmp(tok, "physical_volumes {") == 0) {
950 			VOL_FOREACH(llvm_textconf_decode_pv, tok, &buf, vg);
951 			continue;
952 		}
953 		if (strcmp(tok, "logical_volumes {") == 0) {
954 			VOL_FOREACH(llvm_textconf_decode_lv, tok, &buf, vg);
955 			continue;
956 		}
957 		if (strstr(tok, "{")) {
958 			G_LLVM_DEBUG(2, "unknown section %s", tok);
959 			continue;
960 		}
961 
962 		/* parse 'key = value' lines */
963 		if (strstr(tok, "=")) {
964 			SPLIT(v, tok, "=");
965 			GRAB_STR("id", v, tok, vg->vg_uuid, sizeof(vg->vg_uuid));
966 			GRAB_INT("extent_size", v, tok, vg->vg_extentsize);
967 			continue;
968 		}
969 	}
970 	/* basic checking */
971 	if (vg->vg_extentsize == 0)
972 		goto bad;
973 
974 	md->md_vg = vg;
975 	LIST_INSERT_HEAD(&vg_list, vg, vg_next);
976 	G_LLVM_DEBUG(3, "vg: name=%s uuid=%s", vg->vg_name, vg->vg_uuid);
977 	return(0);
978 
979 bad:
980 	g_llvm_free_vg(vg);
981 	return (-1);
982 }
983 #undef	VOL_FOREACH
984 
985 static int
986 llvm_textconf_decode_pv(char **buf, char *tok, struct g_llvm_vg *vg)
987 {
988 	struct g_llvm_pv	*pv;
989 	char *v;
990 	size_t len;
991 
992 	if (*buf == NULL || **buf == '\0')
993 		return (EINVAL);
994 
995 	pv = malloc(sizeof(*pv), M_GLLVM, M_NOWAIT|M_ZERO);
996 	if (pv == NULL)
997 		return (ENOMEM);
998 
999 	pv->pv_vg = vg;
1000 	len = 0;
1001 	if (tok == NULL)
1002 		goto bad;
1003 	len = llvm_grab_name(pv->pv_name, tok);
1004 	if (len == 0)
1005 		goto bad;
1006 
1007 	while ((tok = strsep(buf, "\n")) != NULL) {
1008 		if (strstr(tok, "{"))
1009 			goto bad;
1010 
1011 		if (strstr(tok, "}"))
1012 			break;
1013 
1014 		/* parse 'key = value' lines */
1015 		if (strstr(tok, "=")) {
1016 			SPLIT(v, tok, "=");
1017 			GRAB_STR("id", v, tok, pv->pv_uuid, sizeof(pv->pv_uuid));
1018 			GRAB_INT("pe_start", v, tok, pv->pv_start);
1019 			GRAB_INT("pe_count", v, tok, pv->pv_count);
1020 			continue;
1021 		}
1022 	}
1023 	if (tok == NULL)
1024 		goto bad;
1025 	/* basic checking */
1026 	if (pv->pv_count == 0)
1027 		goto bad;
1028 
1029 	LIST_INSERT_HEAD(&vg->vg_pvs, pv, pv_next);
1030 	G_LLVM_DEBUG(3, "pv: name=%s uuid=%s", pv->pv_name, pv->pv_uuid);
1031 
1032 	return (0);
1033 bad:
1034 	free(pv, M_GLLVM);
1035 	return (-1);
1036 }
1037 
1038 static int
1039 llvm_textconf_decode_lv(char **buf, char *tok, struct g_llvm_vg *vg)
1040 {
1041 	struct g_llvm_lv	*lv;
1042 	struct g_llvm_segment *sg;
1043 	char *v;
1044 	size_t len;
1045 
1046 	if (*buf == NULL || **buf == '\0')
1047 		return (EINVAL);
1048 
1049 	lv = malloc(sizeof(*lv), M_GLLVM, M_NOWAIT|M_ZERO);
1050 	if (lv == NULL)
1051 		return (ENOMEM);
1052 
1053 	lv->lv_vg = vg;
1054 	LIST_INIT(&lv->lv_segs);
1055 
1056 	if (tok == NULL)
1057 		goto bad;
1058 	len = llvm_grab_name(lv->lv_name, tok);
1059 	if (len == 0)
1060 		goto bad;
1061 
1062 	while ((tok = strsep(buf, "\n")) != NULL) {
1063 		if (strstr(tok, "{")) {
1064 			if (strstr(tok, "segment")) {
1065 				llvm_textconf_decode_sg(buf, tok, lv);
1066 				continue;
1067 			} else
1068 				/* unexpected section */
1069 				goto bad;
1070 		}
1071 
1072 		if (strstr(tok, "}"))
1073 			break;
1074 
1075 		/* parse 'key = value' lines */
1076 		if (strstr(tok, "=")) {
1077 			SPLIT(v, tok, "=");
1078 			GRAB_STR("id", v, tok, lv->lv_uuid, sizeof(lv->lv_uuid));
1079 			GRAB_INT("segment_count", v, tok, lv->lv_sgcount);
1080 			continue;
1081 		}
1082 	}
1083 	if (tok == NULL)
1084 		goto bad;
1085 	if (lv->lv_sgcount == 0 || lv->lv_sgcount != lv->lv_numsegs)
1086 		/* zero or incomplete segment list */
1087 		goto bad;
1088 
1089 	/* Optimize for only one segment on the pv */
1090 	lv->lv_firstsg = LIST_FIRST(&lv->lv_segs);
1091 	LIST_INSERT_HEAD(&vg->vg_lvs, lv, lv_next);
1092 	G_LLVM_DEBUG(3, "lv: name=%s uuid=%s", lv->lv_name, lv->lv_uuid);
1093 
1094 	return (0);
1095 bad:
1096 	while ((sg = LIST_FIRST(&lv->lv_segs)) != NULL) {
1097 		LIST_REMOVE(sg, sg_next);
1098 		free(sg, M_GLLVM);
1099 	}
1100 	free(lv, M_GLLVM);
1101 	return (-1);
1102 }
1103 
1104 static int
1105 llvm_textconf_decode_sg(char **buf, char *tok, struct g_llvm_lv *lv)
1106 {
1107 	struct g_llvm_segment *sg;
1108 	char *v;
1109 	int count = 0;
1110 
1111 	if (*buf == NULL || **buf == '\0')
1112 		return (EINVAL);
1113 
1114 	sg = malloc(sizeof(*sg), M_GLLVM, M_NOWAIT|M_ZERO);
1115 	if (sg == NULL)
1116 		return (ENOMEM);
1117 
1118 	while ((tok = strsep(buf, "\n")) != NULL) {
1119 		/* only a single linear stripe is supported */
1120 		if (strstr(tok, "stripe_count")) {
1121 			SPLIT(v, tok, "=");
1122 			GRAB_INT("stripe_count", v, tok, count);
1123 			if (count != 1)
1124 				goto bad;
1125 		}
1126 
1127 		if (strstr(tok, "{"))
1128 			goto bad;
1129 
1130 		if (strstr(tok, "}"))
1131 			break;
1132 
1133 		if (strcmp(tok, "stripes = [") == 0) {
1134 			tok = strsep(buf, "\n");
1135 			if (tok == NULL)
1136 				goto bad;
1137 
1138 			strsep(&tok, "\"");
1139 			if (tok == NULL)
1140 				goto bad;	/* missing open quotes */
1141 			v = strsep(&tok, "\"");
1142 			if (tok == NULL)
1143 				goto bad;	/* missing close quotes */
1144 			strncpy(sg->sg_pvname, v, sizeof(sg->sg_pvname));
1145 			if (*tok != ',')
1146 				goto bad;	/* missing comma for stripe */
1147 			tok++;
1148 
1149 			sg->sg_pvstart = strtol(tok, &v, 10);
1150 			if (v == tok)
1151 				/* strtol did not eat any of the buffer */
1152 				goto bad;
1153 
1154 			continue;
1155 		}
1156 
1157 		/* parse 'key = value' lines */
1158 		if (strstr(tok, "=")) {
1159 			SPLIT(v, tok, "=");
1160 			GRAB_INT("start_extent", v, tok, sg->sg_start);
1161 			GRAB_INT("extent_count", v, tok, sg->sg_count);
1162 			continue;
1163 		}
1164 	}
1165 	if (tok == NULL)
1166 		goto bad;
1167 	/* basic checking */
1168 	if (count != 1 || sg->sg_count == 0)
1169 		goto bad;
1170 
1171 	sg->sg_end = sg->sg_start + sg->sg_count - 1;
1172 	lv->lv_numsegs++;
1173 	lv->lv_extentcount += sg->sg_count;
1174 	LIST_INSERT_HEAD(&lv->lv_segs, sg, sg_next);
1175 
1176 	return (0);
1177 bad:
1178 	free(sg, M_GLLVM);
1179 	return (-1);
1180 }
1181 #undef	GRAB_INT
1182 #undef	GRAB_STR
1183 #undef	SPLIT
1184 
1185 static struct g_class g_llvm_class = {
1186 	.name = G_LLVM_CLASS_NAME,
1187 	.version = G_VERSION,
1188 	.init = g_llvm_init,
1189 	.taste = g_llvm_taste,
1190 	.destroy_geom = g_llvm_destroy_geom
1191 };
1192 
1193 DECLARE_GEOM_CLASS(g_llvm_class, g_linux_lvm);
1194 MODULE_VERSION(geom_linux_lvm, 0);
1195