xref: /freebsd/sys/geom/linux_lvm/g_linux_lvm.c (revision 1d386b48a555f61cb7325543adbbb5c3f3407a66)
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 *, int);
71 static int	llvm_md_decode(const u_char *, struct g_llvm_metadata *,
72 		    struct g_llvm_label *);
73 static int	llvm_textconf_decode(u_char *, int,
74 		    struct g_llvm_metadata *);
75 static int	llvm_textconf_decode_pv(char **, char *, struct g_llvm_vg *);
76 static int	llvm_textconf_decode_lv(char **, char *, struct g_llvm_vg *);
77 static int	llvm_textconf_decode_sg(char **, char *, struct g_llvm_lv *);
78 
79 SYSCTL_DECL(_kern_geom);
80 SYSCTL_NODE(_kern_geom, OID_AUTO, linux_lvm, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
81     "GEOM_LINUX_LVM stuff");
82 static u_int g_llvm_debug = 0;
83 SYSCTL_UINT(_kern_geom_linux_lvm, OID_AUTO, debug, CTLFLAG_RWTUN, &g_llvm_debug, 0,
84     "Debug level");
85 
86 LIST_HEAD(, g_llvm_vg) vg_list;
87 
88 /*
89  * Called to notify geom when it's been opened, and for what intent
90  */
91 static int
92 g_llvm_access(struct g_provider *pp, int dr, int dw, int de)
93 {
94 	struct g_consumer *c;
95 	struct g_llvm_vg *vg;
96 	struct g_geom *gp;
97 	int error;
98 
99 	KASSERT(pp != NULL, ("%s: NULL provider", __func__));
100 	gp = pp->geom;
101 	KASSERT(gp != NULL, ("%s: NULL geom", __func__));
102 	vg = gp->softc;
103 
104 	if (vg == NULL) {
105 		/* It seems that .access can be called with negative dr,dw,dx
106 		 * in this case but I want to check for myself */
107 		G_LLVM_DEBUG(0, "access(%d, %d, %d) for %s",
108 		    dr, dw, de, pp->name);
109 
110 		/* This should only happen when geom is withered so
111 		 * allow only negative requests */
112 		KASSERT(dr <= 0 && dw <= 0 && de <= 0,
113 		    ("%s: Positive access for %s", __func__, pp->name));
114 		if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0)
115 			G_LLVM_DEBUG(0,
116 			    "Device %s definitely destroyed", pp->name);
117 		return (0);
118 	}
119 
120 	/* Grab an exclusive bit to propagate on our consumers on first open */
121 	if (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)
122 		de++;
123 	/* ... drop it on close */
124 	if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0)
125 		de--;
126 
127 	error = ENXIO;
128 	LIST_FOREACH(c, &gp->consumer, consumer) {
129 		KASSERT(c != NULL, ("%s: consumer is NULL", __func__));
130 		error = g_access(c, dr, dw, de);
131 		if (error != 0) {
132 			struct g_consumer *c2;
133 
134 			/* Backout earlier changes */
135 			LIST_FOREACH(c2, &gp->consumer, consumer) {
136 				if (c2 == c) /* all eariler components fixed */
137 					return (error);
138 				g_access(c2, -dr, -dw, -de);
139 			}
140 		}
141 	}
142 
143 	return (error);
144 }
145 
146 /*
147  * Dismantle bio_queue and destroy its components
148  */
149 static void
150 bioq_dismantle(struct bio_queue_head *bq)
151 {
152 	struct bio *b;
153 
154 	for (b = bioq_first(bq); b != NULL; b = bioq_first(bq)) {
155 		bioq_remove(bq, b);
156 		g_destroy_bio(b);
157 	}
158 }
159 
160 /*
161  * GEOM .done handler
162  * Can't use standard handler because one requested IO may
163  * fork into additional data IOs
164  */
165 static void
166 g_llvm_done(struct bio *b)
167 {
168 	struct bio *parent_b;
169 
170 	parent_b = b->bio_parent;
171 
172 	if (b->bio_error != 0) {
173 		G_LLVM_DEBUG(0, "Error %d for offset=%ju, length=%ju on %s",
174 		    b->bio_error, b->bio_offset, b->bio_length,
175 		    b->bio_to->name);
176 		if (parent_b->bio_error == 0)
177 			parent_b->bio_error = b->bio_error;
178 	}
179 
180 	parent_b->bio_inbed++;
181 	parent_b->bio_completed += b->bio_completed;
182 
183 	if (parent_b->bio_children == parent_b->bio_inbed) {
184 		parent_b->bio_completed = parent_b->bio_length;
185 		g_io_deliver(parent_b, parent_b->bio_error);
186 	}
187 	g_destroy_bio(b);
188 }
189 
190 static void
191 g_llvm_start(struct bio *bp)
192 {
193 	struct g_provider *pp;
194 	struct g_llvm_vg *vg;
195 	struct g_llvm_pv *pv;
196 	struct g_llvm_lv *lv;
197 	struct g_llvm_segment *sg;
198 	struct bio *cb;
199 	struct bio_queue_head bq;
200 	size_t chunk_size;
201 	off_t offset, length;
202 	char *addr;
203 	u_int count;
204 
205 	pp = bp->bio_to;
206 	lv = pp->private;
207 	vg = pp->geom->softc;
208 
209 	switch (bp->bio_cmd) {
210 	case BIO_READ:
211 	case BIO_WRITE:
212 	case BIO_DELETE:
213 	/* XXX BIO_GETATTR allowed? */
214 		break;
215 	default:
216 		/*
217 		 * BIO_SPEEDUP and BIO_FLUSH should pass through to all sg
218 		 * elements, but aren't.
219 		 */
220 		g_io_deliver(bp, EOPNOTSUPP);
221 		return;
222 	}
223 
224 	bioq_init(&bq);
225 
226 	chunk_size = vg->vg_extentsize;
227 	addr = bp->bio_data;
228 	offset = bp->bio_offset;	/* virtual offset and length */
229 	length = bp->bio_length;
230 
231 	while (length > 0) {
232 		size_t chunk_index, in_chunk_offset, in_chunk_length;
233 
234 		pv = NULL;
235 		cb = g_clone_bio(bp);
236 		if (cb == NULL) {
237 			bioq_dismantle(&bq);
238 			if (bp->bio_error == 0)
239 				bp->bio_error = ENOMEM;
240 			g_io_deliver(bp, bp->bio_error);
241 			return;
242 		}
243 
244 		/* get the segment and the pv */
245 		if (lv->lv_sgcount == 1) {
246 			/* skip much of the calculations for a single sg */
247 			chunk_index = 0;
248 			in_chunk_offset = 0;
249 			in_chunk_length = length;
250 			sg = lv->lv_firstsg;
251 			pv = sg->sg_pv;
252 			cb->bio_offset = offset + sg->sg_pvoffset;
253 		} else {
254 			chunk_index = offset / chunk_size; /* round downwards */
255 			in_chunk_offset = offset % chunk_size;
256 			in_chunk_length =
257 			    min(length, chunk_size - in_chunk_offset);
258 
259 			/* XXX could be faster */
260 			LIST_FOREACH(sg, &lv->lv_segs, sg_next) {
261 				if (chunk_index >= sg->sg_start &&
262 				    chunk_index <= sg->sg_end) {
263 					/* adjust chunk index for sg start */
264 					chunk_index -= sg->sg_start;
265 					pv = sg->sg_pv;
266 					break;
267 				}
268 			}
269 			cb->bio_offset =
270 			    (off_t)chunk_index * (off_t)chunk_size
271 			    + in_chunk_offset + sg->sg_pvoffset;
272 		}
273 
274 		KASSERT(pv != NULL, ("Can't find PV for chunk %zu",
275 		    chunk_index));
276 
277 		cb->bio_to = pv->pv_gprov;
278 		cb->bio_done = g_llvm_done;
279 		cb->bio_length = in_chunk_length;
280 		cb->bio_data = addr;
281 		cb->bio_caller1 = pv;
282 		bioq_disksort(&bq, cb);
283 
284 		G_LLVM_DEBUG(5,
285 		    "Mapped %s(%ju, %ju) on %s to %zu(%zu,%zu) @ %s:%ju",
286 		    bp->bio_cmd == BIO_READ ? "R" : "W",
287 		    offset, length, lv->lv_name,
288 		    chunk_index, in_chunk_offset, in_chunk_length,
289 		    pv->pv_name, cb->bio_offset);
290 
291 		addr += in_chunk_length;
292 		length -= in_chunk_length;
293 		offset += in_chunk_length;
294 	}
295 
296 	/* Fire off bio's here */
297 	count = 0;
298 	for (cb = bioq_first(&bq); cb != NULL; cb = bioq_first(&bq)) {
299 		bioq_remove(&bq, cb);
300 		pv = cb->bio_caller1;
301 		cb->bio_caller1 = NULL;
302 		G_LLVM_DEBUG(6, "firing bio to %s, offset=%ju, length=%ju",
303 		    cb->bio_to->name, cb->bio_offset, cb->bio_length);
304 		g_io_request(cb, pv->pv_gcons);
305 		count++;
306 	}
307 	if (count == 0) { /* We handled everything locally */
308 		bp->bio_completed = bp->bio_length;
309 		g_io_deliver(bp, 0);
310 	}
311 }
312 
313 static void
314 g_llvm_remove_disk(struct g_llvm_vg *vg, struct g_consumer *cp)
315 {
316 	struct g_llvm_pv *pv;
317 	struct g_llvm_lv *lv;
318 	struct g_llvm_segment *sg;
319 	int found;
320 
321 	KASSERT(cp != NULL, ("Non-valid disk in %s.", __func__));
322 	pv = (struct g_llvm_pv *)cp->private;
323 
324 	G_LLVM_DEBUG(0, "Disk %s removed from %s.", cp->provider->name,
325 	    pv->pv_name);
326 
327 	LIST_FOREACH(lv, &vg->vg_lvs, lv_next) {
328 		/* Find segments that map to this disk */
329 		found = 0;
330 		LIST_FOREACH(sg, &lv->lv_segs, sg_next) {
331 			if (sg->sg_pv == pv) {
332 				sg->sg_pv = NULL;
333 				lv->lv_sgactive--;
334 				found = 1;
335 				break;
336 			}
337 		}
338 		if (found) {
339 			G_LLVM_DEBUG(0, "Device %s removed.",
340 			    lv->lv_gprov->name);
341 			g_wither_provider(lv->lv_gprov, ENXIO);
342 			lv->lv_gprov = NULL;
343 		}
344 	}
345 
346 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
347 		g_access(cp, -cp->acr, -cp->acw, -cp->ace);
348 	g_detach(cp);
349 	g_destroy_consumer(cp);
350 }
351 
352 static void
353 g_llvm_orphan(struct g_consumer *cp)
354 {
355 	struct g_llvm_vg *vg;
356 	struct g_geom *gp;
357 
358 	g_topology_assert();
359 	gp = cp->geom;
360 	vg = gp->softc;
361 	if (vg == NULL)
362 		return;
363 
364 	g_llvm_remove_disk(vg, cp);
365 	g_llvm_destroy(vg, 1);
366 }
367 
368 static int
369 g_llvm_activate_lv(struct g_llvm_vg *vg, struct g_llvm_lv *lv)
370 {
371 	struct g_geom *gp;
372 	struct g_provider *pp;
373 
374 	g_topology_assert();
375 
376 	KASSERT(lv->lv_sgactive == lv->lv_sgcount, ("segment missing"));
377 
378 	gp = vg->vg_geom;
379 	pp = g_new_providerf(gp, "linux_lvm/%s-%s", vg->vg_name, lv->lv_name);
380 	pp->mediasize = vg->vg_extentsize * (off_t)lv->lv_extentcount;
381 	pp->sectorsize = vg->vg_sectorsize;
382 	g_error_provider(pp, 0);
383 	lv->lv_gprov = pp;
384 	pp->private = lv;
385 
386 	G_LLVM_DEBUG(1, "Created %s, %juM", pp->name,
387 	    pp->mediasize / (1024*1024));
388 
389 	return (0);
390 }
391 
392 static int
393 g_llvm_add_disk(struct g_llvm_vg *vg, struct g_provider *pp, char *uuid)
394 {
395 	struct g_geom *gp;
396 	struct g_consumer *cp, *fcp;
397 	struct g_llvm_pv *pv;
398 	struct g_llvm_lv *lv;
399 	struct g_llvm_segment *sg;
400 	int error;
401 
402 	g_topology_assert();
403 
404 	LIST_FOREACH(pv, &vg->vg_pvs, pv_next) {
405 		if (strcmp(pv->pv_uuid, uuid) == 0)
406 			break;	/* found it */
407 	}
408 	if (pv == NULL) {
409 		G_LLVM_DEBUG(3, "uuid %s not found in pv list", uuid);
410 		return (ENOENT);
411 	}
412 	if (pv->pv_gprov != NULL) {
413 		G_LLVM_DEBUG(0, "disk %s already initialised in %s",
414 		    pv->pv_name, vg->vg_name);
415 		return (EEXIST);
416 	}
417 
418 	pv->pv_start *= vg->vg_sectorsize;
419 	gp = vg->vg_geom;
420 	fcp = LIST_FIRST(&gp->consumer);
421 
422 	cp = g_new_consumer(gp);
423 	error = g_attach(cp, pp);
424 	G_LLVM_DEBUG(1, "Attached %s to %s at offset %ju",
425 	    pp->name, pv->pv_name, pv->pv_start);
426 
427 	if (error != 0) {
428 		G_LLVM_DEBUG(0, "cannot attach %s to %s",
429 		    pp->name, vg->vg_name);
430 		g_destroy_consumer(cp);
431 		return (error);
432 	}
433 
434 	if (fcp != NULL) {
435 		if (fcp->provider->sectorsize != pp->sectorsize) {
436 			G_LLVM_DEBUG(0, "Provider %s of %s has invalid "
437 			    "sector size (%d)", pp->name, vg->vg_name,
438 			    pp->sectorsize);
439 			return (EINVAL);
440 		}
441 		if (fcp->acr > 0 || fcp->acw || fcp->ace > 0) {
442 			/* Replicate access permissions from first "live"
443 			 * consumer to the new one */
444 			error = g_access(cp, fcp->acr, fcp->acw, fcp->ace);
445 			if (error != 0) {
446 				g_detach(cp);
447 				g_destroy_consumer(cp);
448 				return (error);
449 			}
450 		}
451 	}
452 
453 	cp->private = pv;
454 	pv->pv_gcons = cp;
455 	pv->pv_gprov = pp;
456 
457 	LIST_FOREACH(lv, &vg->vg_lvs, lv_next) {
458 		/* Find segments that map to this disk */
459 		LIST_FOREACH(sg, &lv->lv_segs, sg_next) {
460 			if (strcmp(sg->sg_pvname, pv->pv_name) == 0) {
461 				/* avtivate the segment */
462 				KASSERT(sg->sg_pv == NULL,
463 				    ("segment already mapped"));
464 				sg->sg_pvoffset =
465 				    (off_t)sg->sg_pvstart * vg->vg_extentsize
466 				    + pv->pv_start;
467 				sg->sg_pv = pv;
468 				lv->lv_sgactive++;
469 
470 				G_LLVM_DEBUG(2, "%s: %d to %d @ %s:%d"
471 				    " offset %ju sector %ju",
472 				    lv->lv_name, sg->sg_start, sg->sg_end,
473 				    sg->sg_pvname, sg->sg_pvstart,
474 				    sg->sg_pvoffset,
475 				    sg->sg_pvoffset / vg->vg_sectorsize);
476 			}
477 		}
478 		/* Activate any lvs waiting on this disk */
479 		if (lv->lv_gprov == NULL && lv->lv_sgactive == lv->lv_sgcount) {
480 			error = g_llvm_activate_lv(vg, lv);
481 			if (error)
482 				break;
483 		}
484 	}
485 	return (error);
486 }
487 
488 static void
489 g_llvm_init(struct g_class *mp)
490 {
491 	LIST_INIT(&vg_list);
492 }
493 
494 static void
495 g_llvm_free_vg(struct g_llvm_vg *vg)
496 {
497 	struct g_llvm_pv *pv;
498 	struct g_llvm_lv *lv;
499 	struct g_llvm_segment *sg;
500 
501 	/* Free all the structures */
502 	while ((pv = LIST_FIRST(&vg->vg_pvs)) != NULL) {
503 		LIST_REMOVE(pv, pv_next);
504 		free(pv, M_GLLVM);
505 	}
506 	while ((lv = LIST_FIRST(&vg->vg_lvs)) != NULL) {
507 		while ((sg = LIST_FIRST(&lv->lv_segs)) != NULL) {
508 			LIST_REMOVE(sg, sg_next);
509 			free(sg, M_GLLVM);
510 		}
511 		LIST_REMOVE(lv, lv_next);
512 		free(lv, M_GLLVM);
513 	}
514 	LIST_REMOVE(vg, vg_next);
515 	free(vg, M_GLLVM);
516 }
517 
518 static void
519 g_llvm_taste_orphan(struct g_consumer *cp)
520 {
521 
522 	KASSERT(1 == 0, ("%s called while tasting %s.", __func__,
523 	    cp->provider->name));
524 }
525 
526 static struct g_geom *
527 g_llvm_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
528 {
529 	struct g_consumer *cp;
530 	struct g_geom *gp;
531 	struct g_llvm_label ll;
532 	struct g_llvm_metadata md;
533 	struct g_llvm_vg *vg;
534 	int error;
535 
536 	bzero(&md, sizeof(md));
537 
538 	g_topology_assert();
539 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
540 	gp = g_new_geomf(mp, "linux_lvm:taste");
541 	/* This orphan function should be never called. */
542 	gp->orphan = g_llvm_taste_orphan;
543 	cp = g_new_consumer(gp);
544 	cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
545 	error = g_attach(cp, pp);
546 	if (error == 0) {
547 		error = g_llvm_read_label(cp, &ll);
548 		if (error == 0)
549 			error = g_llvm_read_md(cp, &md, &ll);
550 		g_detach(cp);
551 	}
552 	g_destroy_consumer(cp);
553 	g_destroy_geom(gp);
554 	if (error != 0)
555 		return (NULL);
556 
557 	vg = md.md_vg;
558 	if (vg->vg_geom == NULL) {
559 		/* new volume group */
560 		gp = g_new_geomf(mp, "%s", vg->vg_name);
561 		gp->start = g_llvm_start;
562 		gp->spoiled = g_llvm_orphan;
563 		gp->orphan = g_llvm_orphan;
564 		gp->access = g_llvm_access;
565 		vg->vg_sectorsize = pp->sectorsize;
566 		vg->vg_extentsize *= vg->vg_sectorsize;
567 		vg->vg_geom = gp;
568 		gp->softc = vg;
569 		G_LLVM_DEBUG(1, "Created volume %s, extent size %zuK",
570 		    vg->vg_name, vg->vg_extentsize / 1024);
571 	}
572 
573 	/* initialise this disk in the volume group */
574 	g_llvm_add_disk(vg, pp, ll.ll_uuid);
575 	return (vg->vg_geom);
576 }
577 
578 static int
579 g_llvm_destroy(struct g_llvm_vg *vg, int force)
580 {
581 	struct g_provider *pp;
582 	struct g_geom *gp;
583 
584 	g_topology_assert();
585 	if (vg == NULL)
586 		return (ENXIO);
587 	gp = vg->vg_geom;
588 
589 	LIST_FOREACH(pp, &gp->provider, provider) {
590 		if (pp->acr != 0 || pp->acw != 0 || pp->ace != 0) {
591 			G_LLVM_DEBUG(1, "Device %s is still open (r%dw%de%d)",
592 			    pp->name, pp->acr, pp->acw, pp->ace);
593 			if (!force)
594 				return (EBUSY);
595 		}
596 	}
597 
598 	g_llvm_free_vg(gp->softc);
599 	gp->softc = NULL;
600 	g_wither_geom(gp, ENXIO);
601 	return (0);
602 }
603 
604 static int
605 g_llvm_destroy_geom(struct gctl_req *req __unused, struct g_class *mp __unused,
606     struct g_geom *gp)
607 {
608 	struct g_llvm_vg *vg;
609 
610 	vg = gp->softc;
611 	return (g_llvm_destroy(vg, 0));
612 }
613 
614 int
615 g_llvm_read_label(struct g_consumer *cp, struct g_llvm_label *ll)
616 {
617 	struct g_provider *pp;
618 	u_char *buf;
619 	int i, error = 0;
620 
621 	g_topology_assert();
622 
623 	/* The LVM label is stored on the first four sectors */
624 	error = g_access(cp, 1, 0, 0);
625 	if (error != 0)
626 		return (error);
627 	pp = cp->provider;
628 	g_topology_unlock();
629 	buf = g_read_data(cp, 0, pp->sectorsize * 4, &error);
630 	g_topology_lock();
631 	g_access(cp, -1, 0, 0);
632 	if (buf == NULL) {
633 		G_LLVM_DEBUG(1, "Cannot read metadata from %s (error=%d)",
634 		    pp->name, error);
635 		return (error);
636 	}
637 
638 	/* Search the four sectors for the LVM label. */
639 	for (i = 0; i < 4; i++) {
640 		error = llvm_label_decode(&buf[i * pp->sectorsize], ll, i);
641 		if (error == 0)
642 			break;	/* found it */
643 	}
644 	g_free(buf);
645 	return (error);
646 }
647 
648 int
649 g_llvm_read_md(struct g_consumer *cp, struct g_llvm_metadata *md,
650     struct g_llvm_label *ll)
651 {
652 	struct g_provider *pp;
653 	u_char *buf;
654 	int error;
655 	int size;
656 
657 	g_topology_assert();
658 
659 	error = g_access(cp, 1, 0, 0);
660 	if (error != 0)
661 		return (error);
662 	pp = cp->provider;
663 	g_topology_unlock();
664 	buf = g_read_data(cp, ll->ll_md_offset, pp->sectorsize, &error);
665 	g_topology_lock();
666 	g_access(cp, -1, 0, 0);
667 	if (buf == NULL) {
668 		G_LLVM_DEBUG(0, "Cannot read metadata from %s (error=%d)",
669 		    cp->provider->name, error);
670 		return (error);
671 	}
672 
673 	error = llvm_md_decode(buf, md, ll);
674 	g_free(buf);
675 	if (error != 0) {
676 		return (error);
677 	}
678 
679 	G_LLVM_DEBUG(1, "reading LVM2 config @ %s:%ju", pp->name,
680 		    ll->ll_md_offset + md->md_reloffset);
681 	error = g_access(cp, 1, 0, 0);
682 	if (error != 0)
683 		return (error);
684 	pp = cp->provider;
685 	g_topology_unlock();
686 	/* round up to the nearest sector */
687 	size = md->md_relsize +
688 	    (pp->sectorsize - md->md_relsize % pp->sectorsize);
689 	buf = g_read_data(cp, ll->ll_md_offset + md->md_reloffset, size, &error);
690 	g_topology_lock();
691 	g_access(cp, -1, 0, 0);
692 	if (buf == NULL) {
693 		G_LLVM_DEBUG(0, "Cannot read LVM2 config from %s (error=%d)",
694 		    pp->name, error);
695 		return (error);
696 	}
697 	buf[md->md_relsize] = '\0';
698 	G_LLVM_DEBUG(10, "LVM config:\n%s\n", buf);
699 	error = llvm_textconf_decode(buf, md->md_relsize, md);
700 	g_free(buf);
701 
702 	return (error);
703 }
704 
705 static int
706 llvm_label_decode(const u_char *data, struct g_llvm_label *ll, int sector)
707 {
708 	uint64_t off;
709 	char *uuid;
710 
711 	/* Magic string */
712 	if (bcmp("LABELONE", data , 8) != 0)
713 		return (EINVAL);
714 
715 	/* We only support LVM2 text format */
716 	if (bcmp("LVM2 001", data + 24, 8) != 0) {
717 		G_LLVM_DEBUG(0, "Unsupported LVM format");
718 		return (EINVAL);
719 	}
720 
721 	ll->ll_sector = le64dec(data + 8);
722 	ll->ll_crc = le32dec(data + 16);
723 	ll->ll_offset = le32dec(data + 20);
724 
725 	if (ll->ll_sector != sector) {
726 		G_LLVM_DEBUG(0, "Expected sector %ju, found at %d",
727 		    ll->ll_sector, sector);
728 		return (EINVAL);
729 	}
730 
731 	off = ll->ll_offset;
732 	/*
733 	 * convert the binary uuid to string format, the format is
734 	 * xxxxxx-xxxx-xxxx-xxxx-xxxx-xxxx-xxxxxx (6-4-4-4-4-4-6)
735 	 */
736 	uuid = ll->ll_uuid;
737 	bcopy(data + off, uuid, 6);
738 	off += 6;
739 	uuid += 6;
740 	*uuid++ = '-';
741 	for (int i = 0; i < 5; i++) {
742 		bcopy(data + off, uuid, 4);
743 		off += 4;
744 		uuid += 4;
745 		*uuid++ = '-';
746 	}
747 	bcopy(data + off, uuid, 6);
748 	off += 6;
749 	uuid += 6;
750 	*uuid++ = '\0';
751 
752 	ll->ll_size = le64dec(data + off);
753 	off += 8;
754 	ll->ll_pestart = le64dec(data + off);
755 	off += 16;
756 
757 	/* Only one data section is supported */
758 	if (le64dec(data + off) != 0) {
759 		G_LLVM_DEBUG(0, "Only one data section supported");
760 		return (EINVAL);
761 	}
762 
763 	off += 16;
764 	ll->ll_md_offset = le64dec(data + off);
765 	off += 8;
766 	ll->ll_md_size = le64dec(data + off);
767 	off += 8;
768 
769 	G_LLVM_DEBUG(1, "LVM metadata: offset=%ju, size=%ju", ll->ll_md_offset,
770 	    ll->ll_md_size);
771 
772 	/* Only one data section is supported */
773 	if (le64dec(data + off) != 0) {
774 		G_LLVM_DEBUG(0, "Only one metadata section supported");
775 		return (EINVAL);
776 	}
777 
778 	G_LLVM_DEBUG(2, "label uuid=%s", ll->ll_uuid);
779 	G_LLVM_DEBUG(2, "sector=%ju, crc=%u, offset=%u, size=%ju, pestart=%ju",
780 	    ll->ll_sector, ll->ll_crc, ll->ll_offset, ll->ll_size,
781 	    ll->ll_pestart);
782 
783 	return (0);
784 }
785 
786 static int
787 llvm_md_decode(const u_char *data, struct g_llvm_metadata *md,
788     struct g_llvm_label *ll)
789 {
790 	uint64_t off;
791 	char magic[16];
792 
793 	off = 0;
794 	md->md_csum = le32dec(data + off);
795 	off += 4;
796 	bcopy(data + off, magic, 16);
797 	off += 16;
798 	md->md_version = le32dec(data + off);
799 	off += 4;
800 	md->md_start = le64dec(data + off);
801 	off += 8;
802 	md->md_size = le64dec(data + off);
803 	off += 8;
804 
805 	if (bcmp(G_LLVM_MAGIC, magic, 16) != 0) {
806 		G_LLVM_DEBUG(0, "Incorrect md magic number");
807 		return (EINVAL);
808 	}
809 	if (md->md_version != 1) {
810 		G_LLVM_DEBUG(0, "Incorrect md version number (%u)",
811 		    md->md_version);
812 		return (EINVAL);
813 	}
814 	if (md->md_start != ll->ll_md_offset) {
815 		G_LLVM_DEBUG(0, "Incorrect md offset (%ju)", md->md_start);
816 		return (EINVAL);
817 	}
818 
819 	/* Aparently only one is ever returned */
820 	md->md_reloffset = le64dec(data + off);
821 	off += 8;
822 	md->md_relsize = le64dec(data + off);
823 	off += 16;	/* XXX skipped checksum */
824 
825 	if (le64dec(data + off) != 0) {
826 		G_LLVM_DEBUG(0, "Only one reloc supported");
827 		return (EINVAL);
828 	}
829 
830 	G_LLVM_DEBUG(3, "reloc: offset=%ju, size=%ju",
831 	    md->md_reloffset, md->md_relsize);
832 	G_LLVM_DEBUG(3, "md: version=%u, start=%ju, size=%ju",
833 	    md->md_version, md->md_start, md->md_size);
834 
835 	return (0);
836 }
837 
838 #define	GRAB_INT(key, tok1, tok2, v)					\
839 	if (tok1 && tok2 && strncmp(tok1, key, sizeof(key)) == 0) {	\
840 		v = strtol(tok2, &tok1, 10);				\
841 		if (tok1 == tok2)					\
842 			/* strtol did not eat any of the buffer */	\
843 			goto bad;					\
844 		continue;						\
845 	}
846 
847 #define	GRAB_STR(key, tok1, tok2, v, len)				\
848 	if (tok1 && tok2 && strncmp(tok1, key, sizeof(key)) == 0) {	\
849 		strsep(&tok2, "\"");					\
850 		if (tok2 == NULL)					\
851 			continue;					\
852 		tok1 = strsep(&tok2, "\"");				\
853 		if (tok2 == NULL)					\
854 			continue;					\
855 		strncpy(v, tok1, len);					\
856 		continue;						\
857 	}
858 
859 #define	SPLIT(key, value, str)						\
860 	key = strsep(&value, str);					\
861 	/* strip trailing whitespace on the key */			\
862 	for (char *t = key; *t != '\0'; t++)				\
863 		if (isspace(*t)) {					\
864 			*t = '\0';					\
865 			break;						\
866 		}
867 
868 static size_t
869 llvm_grab_name(char *name, const char *tok)
870 {
871 	size_t len;
872 
873 	len = 0;
874 	if (tok == NULL)
875 		return (0);
876 	if (tok[0] == '-')
877 		return (0);
878 	if (strcmp(tok, ".") == 0 || strcmp(tok, "..") == 0)
879 		return (0);
880 	while (tok[len] && (isalpha(tok[len]) || isdigit(tok[len]) ||
881 	    tok[len] == '.' || tok[len] == '_' || tok[len] == '-' ||
882 	    tok[len] == '+') && len < G_LLVM_NAMELEN - 1)
883 		len++;
884 	bcopy(tok, name, len);
885 	name[len] = '\0';
886 	return (len);
887 }
888 
889 static int
890 llvm_textconf_decode(u_char *data, int buflen, struct g_llvm_metadata *md)
891 {
892 	struct g_llvm_vg	*vg;
893 	char *buf = data;
894 	char *tok, *v;
895 	char name[G_LLVM_NAMELEN];
896 	char uuid[G_LLVM_UUIDLEN];
897 	size_t len;
898 
899 	if (buf == NULL || *buf == '\0')
900 		return (EINVAL);
901 
902 	tok = strsep(&buf, "\n");
903 	if (tok == NULL)
904 		return (EINVAL);
905 	len = llvm_grab_name(name, tok);
906 	if (len == 0)
907 		return (EINVAL);
908 
909 	/* check too see if the vg has already been loaded off another disk */
910 	LIST_FOREACH(vg, &vg_list, vg_next) {
911 		if (strcmp(vg->vg_name, name) == 0) {
912 			uuid[0] = '\0';
913 			/* grab the volume group uuid */
914 			while ((tok = strsep(&buf, "\n")) != NULL) {
915 				if (strstr(tok, "{"))
916 					break;
917 				if (strstr(tok, "=")) {
918 					SPLIT(v, tok, "=");
919 					GRAB_STR("id", v, tok, uuid,
920 					    sizeof(uuid));
921 				}
922 			}
923 			if (strcmp(vg->vg_uuid, uuid) == 0) {
924 				/* existing vg */
925 				md->md_vg = vg;
926 				return (0);
927 			}
928 			/* XXX different volume group with name clash! */
929 			G_LLVM_DEBUG(0,
930 			    "%s already exists, volume group not loaded", name);
931 			return (EINVAL);
932 		}
933 	}
934 
935 	vg = malloc(sizeof(*vg), M_GLLVM, M_NOWAIT|M_ZERO);
936 	if (vg == NULL)
937 		return (ENOMEM);
938 
939 	strncpy(vg->vg_name, name, sizeof(vg->vg_name));
940 	LIST_INIT(&vg->vg_pvs);
941 	LIST_INIT(&vg->vg_lvs);
942 
943 #define	VOL_FOREACH(func, tok, buf, p)					\
944 	while ((tok = strsep(buf, "\n")) != NULL) {			\
945 		if (strstr(tok, "{")) {					\
946 			func(buf, tok, p);				\
947 			continue;					\
948 		}							\
949 		if (strstr(tok, "}"))					\
950 			break;						\
951 	}
952 
953 	while ((tok = strsep(&buf, "\n")) != NULL) {
954 		if (strcmp(tok, "physical_volumes {") == 0) {
955 			VOL_FOREACH(llvm_textconf_decode_pv, tok, &buf, vg);
956 			continue;
957 		}
958 		if (strcmp(tok, "logical_volumes {") == 0) {
959 			VOL_FOREACH(llvm_textconf_decode_lv, tok, &buf, vg);
960 			continue;
961 		}
962 		if (strstr(tok, "{")) {
963 			G_LLVM_DEBUG(2, "unknown section %s", tok);
964 			continue;
965 		}
966 
967 		/* parse 'key = value' lines */
968 		if (strstr(tok, "=")) {
969 			SPLIT(v, tok, "=");
970 			GRAB_STR("id", v, tok, vg->vg_uuid, sizeof(vg->vg_uuid));
971 			GRAB_INT("extent_size", v, tok, vg->vg_extentsize);
972 			continue;
973 		}
974 	}
975 	/* basic checking */
976 	if (vg->vg_extentsize == 0)
977 		goto bad;
978 
979 	md->md_vg = vg;
980 	LIST_INSERT_HEAD(&vg_list, vg, vg_next);
981 	G_LLVM_DEBUG(3, "vg: name=%s uuid=%s", vg->vg_name, vg->vg_uuid);
982 	return(0);
983 
984 bad:
985 	g_llvm_free_vg(vg);
986 	return (-1);
987 }
988 #undef	VOL_FOREACH
989 
990 static int
991 llvm_textconf_decode_pv(char **buf, char *tok, struct g_llvm_vg *vg)
992 {
993 	struct g_llvm_pv	*pv;
994 	char *v;
995 	size_t len;
996 
997 	if (*buf == NULL || **buf == '\0')
998 		return (EINVAL);
999 
1000 	pv = malloc(sizeof(*pv), M_GLLVM, M_NOWAIT|M_ZERO);
1001 	if (pv == NULL)
1002 		return (ENOMEM);
1003 
1004 	pv->pv_vg = vg;
1005 	len = 0;
1006 	if (tok == NULL)
1007 		goto bad;
1008 	len = llvm_grab_name(pv->pv_name, tok);
1009 	if (len == 0)
1010 		goto bad;
1011 
1012 	while ((tok = strsep(buf, "\n")) != NULL) {
1013 		if (strstr(tok, "{"))
1014 			goto bad;
1015 
1016 		if (strstr(tok, "}"))
1017 			break;
1018 
1019 		/* parse 'key = value' lines */
1020 		if (strstr(tok, "=")) {
1021 			SPLIT(v, tok, "=");
1022 			GRAB_STR("id", v, tok, pv->pv_uuid, sizeof(pv->pv_uuid));
1023 			GRAB_INT("pe_start", v, tok, pv->pv_start);
1024 			GRAB_INT("pe_count", v, tok, pv->pv_count);
1025 			continue;
1026 		}
1027 	}
1028 	if (tok == NULL)
1029 		goto bad;
1030 	/* basic checking */
1031 	if (pv->pv_count == 0)
1032 		goto bad;
1033 
1034 	LIST_INSERT_HEAD(&vg->vg_pvs, pv, pv_next);
1035 	G_LLVM_DEBUG(3, "pv: name=%s uuid=%s", pv->pv_name, pv->pv_uuid);
1036 
1037 	return (0);
1038 bad:
1039 	free(pv, M_GLLVM);
1040 	return (-1);
1041 }
1042 
1043 static int
1044 llvm_textconf_decode_lv(char **buf, char *tok, struct g_llvm_vg *vg)
1045 {
1046 	struct g_llvm_lv	*lv;
1047 	struct g_llvm_segment *sg;
1048 	char *v;
1049 	size_t len;
1050 
1051 	if (*buf == NULL || **buf == '\0')
1052 		return (EINVAL);
1053 
1054 	lv = malloc(sizeof(*lv), M_GLLVM, M_NOWAIT|M_ZERO);
1055 	if (lv == NULL)
1056 		return (ENOMEM);
1057 
1058 	lv->lv_vg = vg;
1059 	LIST_INIT(&lv->lv_segs);
1060 
1061 	if (tok == NULL)
1062 		goto bad;
1063 	len = llvm_grab_name(lv->lv_name, tok);
1064 	if (len == 0)
1065 		goto bad;
1066 
1067 	while ((tok = strsep(buf, "\n")) != NULL) {
1068 		if (strstr(tok, "{")) {
1069 			if (strstr(tok, "segment")) {
1070 				llvm_textconf_decode_sg(buf, tok, lv);
1071 				continue;
1072 			} else
1073 				/* unexpected section */
1074 				goto bad;
1075 		}
1076 
1077 		if (strstr(tok, "}"))
1078 			break;
1079 
1080 		/* parse 'key = value' lines */
1081 		if (strstr(tok, "=")) {
1082 			SPLIT(v, tok, "=");
1083 			GRAB_STR("id", v, tok, lv->lv_uuid, sizeof(lv->lv_uuid));
1084 			GRAB_INT("segment_count", v, tok, lv->lv_sgcount);
1085 			continue;
1086 		}
1087 	}
1088 	if (tok == NULL)
1089 		goto bad;
1090 	if (lv->lv_sgcount == 0 || lv->lv_sgcount != lv->lv_numsegs)
1091 		/* zero or incomplete segment list */
1092 		goto bad;
1093 
1094 	/* Optimize for only one segment on the pv */
1095 	lv->lv_firstsg = LIST_FIRST(&lv->lv_segs);
1096 	LIST_INSERT_HEAD(&vg->vg_lvs, lv, lv_next);
1097 	G_LLVM_DEBUG(3, "lv: name=%s uuid=%s", lv->lv_name, lv->lv_uuid);
1098 
1099 	return (0);
1100 bad:
1101 	while ((sg = LIST_FIRST(&lv->lv_segs)) != NULL) {
1102 		LIST_REMOVE(sg, sg_next);
1103 		free(sg, M_GLLVM);
1104 	}
1105 	free(lv, M_GLLVM);
1106 	return (-1);
1107 }
1108 
1109 static int
1110 llvm_textconf_decode_sg(char **buf, char *tok, struct g_llvm_lv *lv)
1111 {
1112 	struct g_llvm_segment *sg;
1113 	char *v;
1114 	int count = 0;
1115 
1116 	if (*buf == NULL || **buf == '\0')
1117 		return (EINVAL);
1118 
1119 	sg = malloc(sizeof(*sg), M_GLLVM, M_NOWAIT|M_ZERO);
1120 	if (sg == NULL)
1121 		return (ENOMEM);
1122 
1123 	while ((tok = strsep(buf, "\n")) != NULL) {
1124 		/* only a single linear stripe is supported */
1125 		if (strstr(tok, "stripe_count")) {
1126 			SPLIT(v, tok, "=");
1127 			GRAB_INT("stripe_count", v, tok, count);
1128 			if (count != 1)
1129 				goto bad;
1130 		}
1131 
1132 		if (strstr(tok, "{"))
1133 			goto bad;
1134 
1135 		if (strstr(tok, "}"))
1136 			break;
1137 
1138 		if (strcmp(tok, "stripes = [") == 0) {
1139 			tok = strsep(buf, "\n");
1140 			if (tok == NULL)
1141 				goto bad;
1142 
1143 			strsep(&tok, "\"");
1144 			if (tok == NULL)
1145 				goto bad;	/* missing open quotes */
1146 			v = strsep(&tok, "\"");
1147 			if (tok == NULL)
1148 				goto bad;	/* missing close quotes */
1149 			strncpy(sg->sg_pvname, v, sizeof(sg->sg_pvname));
1150 			if (*tok != ',')
1151 				goto bad;	/* missing comma for stripe */
1152 			tok++;
1153 
1154 			sg->sg_pvstart = strtol(tok, &v, 10);
1155 			if (v == tok)
1156 				/* strtol did not eat any of the buffer */
1157 				goto bad;
1158 
1159 			continue;
1160 		}
1161 
1162 		/* parse 'key = value' lines */
1163 		if (strstr(tok, "=")) {
1164 			SPLIT(v, tok, "=");
1165 			GRAB_INT("start_extent", v, tok, sg->sg_start);
1166 			GRAB_INT("extent_count", v, tok, sg->sg_count);
1167 			continue;
1168 		}
1169 	}
1170 	if (tok == NULL)
1171 		goto bad;
1172 	/* basic checking */
1173 	if (count != 1 || sg->sg_count == 0)
1174 		goto bad;
1175 
1176 	sg->sg_end = sg->sg_start + sg->sg_count - 1;
1177 	lv->lv_numsegs++;
1178 	lv->lv_extentcount += sg->sg_count;
1179 	LIST_INSERT_HEAD(&lv->lv_segs, sg, sg_next);
1180 
1181 	return (0);
1182 bad:
1183 	free(sg, M_GLLVM);
1184 	return (-1);
1185 }
1186 #undef	GRAB_INT
1187 #undef	GRAB_STR
1188 #undef	SPLIT
1189 
1190 static struct g_class g_llvm_class = {
1191 	.name = G_LLVM_CLASS_NAME,
1192 	.version = G_VERSION,
1193 	.init = g_llvm_init,
1194 	.taste = g_llvm_taste,
1195 	.destroy_geom = g_llvm_destroy_geom
1196 };
1197 
1198 DECLARE_GEOM_CLASS(g_llvm_class, g_linux_lvm);
1199 MODULE_VERSION(geom_linux_lvm, 0);
1200