xref: /freebsd/sys/geom/uzip/g_uzip.c (revision e3d7ead7)
1 /*-
2  * Copyright (c) 2004 Max Khon
3  * Copyright (c) 2014 Juniper Networks, Inc.
4  * Copyright (c) 2006-2016 Maxim Sobolev <sobomax@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 AUTHOR 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 AUTHOR 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/param.h>
33 #include <sys/bio.h>
34 #include <sys/endian.h>
35 #include <sys/errno.h>
36 #include <sys/kernel.h>
37 #include <sys/lock.h>
38 #include <sys/mutex.h>
39 #include <sys/malloc.h>
40 #include <sys/sysctl.h>
41 #include <sys/systm.h>
42 #include <sys/kthread.h>
43 
44 #include <geom/geom.h>
45 
46 #include <geom/uzip/g_uzip.h>
47 #include <geom/uzip/g_uzip_cloop.h>
48 #include <geom/uzip/g_uzip_softc.h>
49 #include <geom/uzip/g_uzip_dapi.h>
50 #include <geom/uzip/g_uzip_zlib.h>
51 #include <geom/uzip/g_uzip_lzma.h>
52 #include <geom/uzip/g_uzip_wrkthr.h>
53 
54 #include "opt_geom.h"
55 
56 MALLOC_DEFINE(M_GEOM_UZIP, "geom_uzip", "GEOM UZIP data structures");
57 
58 FEATURE(geom_uzip, "GEOM read-only compressed disks support");
59 
60 struct g_uzip_blk {
61         uint64_t offset;
62         uint32_t blen;
63 #define BLEN_UNDEF      UINT32_MAX
64 };
65 
66 #ifndef ABS
67 #define	ABS(a)			((a) < 0 ? -(a) : (a))
68 #endif
69 
70 #define BLK_IN_RANGE(mcn, bcn, ilen)	\
71     (((bcn) != BLEN_UNDEF) && ( \
72 	((ilen) >= 0 && (mcn >= bcn) && (mcn <= ((intmax_t)(bcn) + (ilen)))) || \
73 	((ilen) < 0 && (mcn <= bcn) && (mcn >= ((intmax_t)(bcn) + (ilen)))) \
74     ))
75 
76 #ifdef GEOM_UZIP_DEBUG
77 # define GEOM_UZIP_DBG_DEFAULT	3
78 #else
79 # define GEOM_UZIP_DBG_DEFAULT	0
80 #endif
81 
82 #define	GUZ_DBG_ERR	1
83 #define	GUZ_DBG_INFO	2
84 #define	GUZ_DBG_IO	3
85 #define	GUZ_DBG_TOC	4
86 
87 SYSCTL_DECL(_kern_geom);
88 SYSCTL_NODE(_kern_geom, OID_AUTO, uzip, CTLFLAG_RW, 0, "GEOM_UZIP stuff");
89 static u_int g_uzip_debug = GEOM_UZIP_DBG_DEFAULT;
90 SYSCTL_UINT(_kern_geom_uzip, OID_AUTO, debug, CTLFLAG_RWTUN, &g_uzip_debug, 0,
91     "Debug level (0-4)");
92 static u_int g_uzip_debug_block = BLEN_UNDEF;
93 SYSCTL_UINT(_kern_geom_uzip, OID_AUTO, debug_block, CTLFLAG_RWTUN,
94     &g_uzip_debug_block, 0, "Debug operations around specific cluster#");
95 
96 #define	DPRINTF(lvl, a)		\
97 	if ((lvl) <= g_uzip_debug) { \
98 		printf a; \
99 	}
100 #define	DPRINTF_BLK(lvl, cn, a)	\
101 	if ((lvl) <= g_uzip_debug || \
102 	    BLK_IN_RANGE(cn, g_uzip_debug_block, 8) || \
103 	    BLK_IN_RANGE(cn, g_uzip_debug_block, -8)) { \
104 		printf a; \
105 	}
106 #define	DPRINTF_BRNG(lvl, bcn, ecn, a) \
107 	KASSERT(bcn < ecn, ("DPRINTF_BRNG: invalid range (%ju, %ju)", \
108 	    (uintmax_t)bcn, (uintmax_t)ecn)); \
109 	if (((lvl) <= g_uzip_debug) || \
110 	    BLK_IN_RANGE(g_uzip_debug_block, bcn, \
111 	     (intmax_t)ecn - (intmax_t)bcn)) { \
112 		printf a; \
113 	}
114 
115 #define	UZIP_CLASS_NAME	"UZIP"
116 
117 /*
118  * Maximum allowed valid block size (to prevent foot-shooting)
119  */
120 #define	MAX_BLKSZ	(MAXPHYS)
121 
122 static char CLOOP_MAGIC_START[] = "#!/bin/sh\n";
123 
124 static void g_uzip_read_done(struct bio *bp);
125 static void g_uzip_do(struct g_uzip_softc *, struct bio *bp);
126 
127 static void
128 g_uzip_softc_free(struct g_uzip_softc *sc, struct g_geom *gp)
129 {
130 
131 	if (gp != NULL) {
132 		DPRINTF(GUZ_DBG_INFO, ("%s: %d requests, %d cached\n",
133 		    gp->name, sc->req_total, sc->req_cached));
134 	}
135 
136 	mtx_lock(&sc->queue_mtx);
137 	sc->wrkthr_flags |= GUZ_SHUTDOWN;
138 	wakeup(sc);
139 	while (!(sc->wrkthr_flags & GUZ_EXITING)) {
140 		msleep(sc->procp, &sc->queue_mtx, PRIBIO, "guzfree",
141 		    hz / 10);
142 	}
143 	mtx_unlock(&sc->queue_mtx);
144 
145 	sc->dcp->free(sc->dcp);
146 	free(sc->toc, M_GEOM_UZIP);
147 	mtx_destroy(&sc->queue_mtx);
148 	mtx_destroy(&sc->last_mtx);
149 	free(sc->last_buf, M_GEOM_UZIP);
150 	free(sc, M_GEOM_UZIP);
151 }
152 
153 static int
154 g_uzip_cached(struct g_geom *gp, struct bio *bp)
155 {
156 	struct g_uzip_softc *sc;
157 	off_t ofs;
158 	size_t blk, blkofs, usz;
159 
160 	sc = gp->softc;
161 	ofs = bp->bio_offset + bp->bio_completed;
162 	blk = ofs / sc->blksz;
163 	mtx_lock(&sc->last_mtx);
164 	if (blk == sc->last_blk) {
165 		blkofs = ofs % sc->blksz;
166 		usz = sc->blksz - blkofs;
167 		if (bp->bio_resid < usz)
168 			usz = bp->bio_resid;
169 		memcpy(bp->bio_data + bp->bio_completed, sc->last_buf + blkofs,
170 		    usz);
171 		sc->req_cached++;
172 		mtx_unlock(&sc->last_mtx);
173 
174 		DPRINTF(GUZ_DBG_IO, ("%s/%s: %p: offset=%jd: got %jd bytes "
175 		    "from cache\n", __func__, gp->name, bp, (intmax_t)ofs,
176 		    (intmax_t)usz));
177 
178 		bp->bio_completed += usz;
179 		bp->bio_resid -= usz;
180 
181 		if (bp->bio_resid == 0) {
182 			g_io_deliver(bp, 0);
183 			return (1);
184 		}
185 	} else
186 		mtx_unlock(&sc->last_mtx);
187 
188 	return (0);
189 }
190 
191 #define BLK_ENDS(sc, bi)	((sc)->toc[(bi)].offset + \
192     (sc)->toc[(bi)].blen)
193 
194 #define BLK_IS_CONT(sc, bi)	(BLK_ENDS((sc), (bi) - 1) == \
195     (sc)->toc[(bi)].offset)
196 #define	BLK_IS_NIL(sc, bi)	((sc)->toc[(bi)].blen == 0)
197 
198 #define TOFF_2_BOFF(sc, pp, bi)	    ((sc)->toc[(bi)].offset - \
199     (sc)->toc[(bi)].offset % (pp)->sectorsize)
200 #define	TLEN_2_BLEN(sc, pp, bp, ei) roundup(BLK_ENDS((sc), (ei)) - \
201     (bp)->bio_offset, (pp)->sectorsize)
202 
203 static int
204 g_uzip_request(struct g_geom *gp, struct bio *bp)
205 {
206 	struct g_uzip_softc *sc;
207 	struct bio *bp2;
208 	struct g_consumer *cp;
209 	struct g_provider *pp;
210 	off_t ofs, start_blk_ofs;
211 	size_t i, start_blk, end_blk, zsize;
212 
213 	if (g_uzip_cached(gp, bp) != 0)
214 		return (1);
215 
216 	sc = gp->softc;
217 
218 	cp = LIST_FIRST(&gp->consumer);
219 	pp = cp->provider;
220 
221 	ofs = bp->bio_offset + bp->bio_completed;
222 	start_blk = ofs / sc->blksz;
223 	KASSERT(start_blk < sc->nblocks, ("start_blk out of range"));
224 	end_blk = howmany(ofs + bp->bio_resid, sc->blksz);
225 	KASSERT(end_blk <= sc->nblocks, ("end_blk out of range"));
226 
227 	for (; BLK_IS_NIL(sc, start_blk) && start_blk < end_blk; start_blk++) {
228 		/* Fill in any leading Nil blocks */
229 		start_blk_ofs = ofs % sc->blksz;
230 		zsize = MIN(sc->blksz - start_blk_ofs, bp->bio_resid);
231 		DPRINTF_BLK(GUZ_DBG_IO, start_blk, ("%s/%s: %p/%ju: "
232 		    "filling %ju zero bytes\n", __func__, gp->name, gp,
233 		    (uintmax_t)bp->bio_completed, (uintmax_t)zsize));
234 		bzero(bp->bio_data + bp->bio_completed, zsize);
235 		bp->bio_completed += zsize;
236 		bp->bio_resid -= zsize;
237 		ofs += zsize;
238 	}
239 
240 	if (start_blk == end_blk) {
241 		KASSERT(bp->bio_resid == 0, ("bp->bio_resid is invalid"));
242 		/*
243 		 * No non-Nil data is left, complete request immediately.
244 		 */
245 		DPRINTF(GUZ_DBG_IO, ("%s/%s: %p: all done returning %ju "
246 		    "bytes\n", __func__, gp->name, gp,
247 		    (uintmax_t)bp->bio_completed));
248 		g_io_deliver(bp, 0);
249 		return (1);
250 	}
251 
252 	for (i = start_blk + 1; i < end_blk; i++) {
253 		/* Trim discontinuous areas if any */
254 		if (!BLK_IS_CONT(sc, i)) {
255 			end_blk = i;
256 			break;
257 		}
258 	}
259 
260 	DPRINTF_BRNG(GUZ_DBG_IO, start_blk, end_blk, ("%s/%s: %p: "
261 	    "start=%u (%ju), end=%u (%ju)\n", __func__, gp->name, bp,
262 	    (u_int)start_blk, (uintmax_t)sc->toc[start_blk].offset,
263 	    (u_int)end_blk, (uintmax_t)BLK_ENDS(sc, end_blk - 1)));
264 
265 	bp2 = g_clone_bio(bp);
266 	if (bp2 == NULL) {
267 		g_io_deliver(bp, ENOMEM);
268 		return (1);
269 	}
270 	bp2->bio_done = g_uzip_read_done;
271 
272 	bp2->bio_offset = TOFF_2_BOFF(sc, pp, start_blk);
273 	while (1) {
274 		bp2->bio_length = TLEN_2_BLEN(sc, pp, bp2, end_blk - 1);
275 		if (bp2->bio_length <= MAXPHYS)
276 			break;
277 		if (end_blk == (start_blk + 1)) {
278 			break;
279 		}
280 		end_blk--;
281 	}
282 
283 	DPRINTF(GUZ_DBG_IO, ("%s/%s: bp2->bio_length = %jd\n",
284 	    __func__, gp->name, (intmax_t)bp2->bio_length));
285 
286 	bp2->bio_data = malloc(bp2->bio_length, M_GEOM_UZIP, M_NOWAIT);
287 	if (bp2->bio_data == NULL) {
288 		g_destroy_bio(bp2);
289 		g_io_deliver(bp, ENOMEM);
290 		return (1);
291 	}
292 
293 	DPRINTF_BRNG(GUZ_DBG_IO, start_blk, end_blk, ("%s/%s: %p: "
294 	    "reading %jd bytes from offset %jd\n", __func__, gp->name, bp,
295 	    (intmax_t)bp2->bio_length, (intmax_t)bp2->bio_offset));
296 
297 	g_io_request(bp2, cp);
298 	return (0);
299 }
300 
301 static void
302 g_uzip_read_done(struct bio *bp)
303 {
304 	struct bio *bp2;
305 	struct g_geom *gp;
306 	struct g_uzip_softc *sc;
307 
308 	bp2 = bp->bio_parent;
309 	gp = bp2->bio_to->geom;
310 	sc = gp->softc;
311 
312 	mtx_lock(&sc->queue_mtx);
313 	bioq_disksort(&sc->bio_queue, bp);
314 	mtx_unlock(&sc->queue_mtx);
315 	wakeup(sc);
316 }
317 
318 static void
319 g_uzip_do(struct g_uzip_softc *sc, struct bio *bp)
320 {
321 	struct bio *bp2;
322 	struct g_provider *pp;
323 	struct g_consumer *cp;
324 	struct g_geom *gp;
325 	char *data, *data2;
326 	off_t ofs;
327 	size_t blk, blkofs, len, ulen, firstblk;
328 	int err;
329 
330 	bp2 = bp->bio_parent;
331 	gp = bp2->bio_to->geom;
332 
333 	cp = LIST_FIRST(&gp->consumer);
334 	pp = cp->provider;
335 
336 	bp2->bio_error = bp->bio_error;
337 	if (bp2->bio_error != 0)
338 		goto done;
339 
340 	/* Make sure there's forward progress. */
341 	if (bp->bio_completed == 0) {
342 		bp2->bio_error = ECANCELED;
343 		goto done;
344 	}
345 
346 	ofs = bp2->bio_offset + bp2->bio_completed;
347 	firstblk = blk = ofs / sc->blksz;
348 	blkofs = ofs % sc->blksz;
349 	data = bp->bio_data + sc->toc[blk].offset % pp->sectorsize;
350 	data2 = bp2->bio_data + bp2->bio_completed;
351 	while (bp->bio_completed && bp2->bio_resid) {
352 		if (blk > firstblk && !BLK_IS_CONT(sc, blk)) {
353 			DPRINTF_BLK(GUZ_DBG_IO, blk, ("%s/%s: %p: backref'ed "
354 			    "cluster #%u requested, looping around\n",
355 			    __func__, gp->name, bp2, (u_int)blk));
356 			goto done;
357 		}
358 		ulen = MIN(sc->blksz - blkofs, bp2->bio_resid);
359 		len = sc->toc[blk].blen;
360 		DPRINTF(GUZ_DBG_IO, ("%s/%s: %p/%ju: data2=%p, ulen=%u, "
361 		    "data=%p, len=%u\n", __func__, gp->name, gp,
362 		    bp->bio_completed, data2, (u_int)ulen, data, (u_int)len));
363 		if (len == 0) {
364 			/* All zero block: no cache update */
365 			bzero(data2, ulen);
366 		} else if (len <= bp->bio_completed) {
367 			mtx_lock(&sc->last_mtx);
368 			err = sc->dcp->decompress(sc->dcp, gp->name, data,
369 			    len, sc->last_buf);
370 			if (err != 0) {
371 				sc->last_blk = -1;
372 				mtx_unlock(&sc->last_mtx);
373 				bp2->bio_error = EILSEQ;
374 				DPRINTF(GUZ_DBG_ERR, ("%s/%s: decompress"
375 				    "(%p) failed\n", __func__, gp->name,
376 				    sc->dcp));
377 				goto done;
378 			}
379 			sc->last_blk = blk;
380 			memcpy(data2, sc->last_buf + blkofs, ulen);
381 			mtx_unlock(&sc->last_mtx);
382 			err = sc->dcp->rewind(sc->dcp, gp->name);
383 			if (err != 0) {
384 				bp2->bio_error = EILSEQ;
385 				DPRINTF(GUZ_DBG_ERR, ("%s/%s: rewind(%p) "
386 				    "failed\n", __func__, gp->name, sc->dcp));
387 				goto done;
388 			}
389 			data += len;
390 		} else
391 			break;
392 
393 		data2 += ulen;
394 		bp2->bio_completed += ulen;
395 		bp2->bio_resid -= ulen;
396 		bp->bio_completed -= len;
397 		blkofs = 0;
398 		blk++;
399 	}
400 
401 done:
402 	/* Finish processing the request. */
403 	free(bp->bio_data, M_GEOM_UZIP);
404 	g_destroy_bio(bp);
405 	if (bp2->bio_error != 0 || bp2->bio_resid == 0)
406 		g_io_deliver(bp2, bp2->bio_error);
407 	else
408 		g_uzip_request(gp, bp2);
409 }
410 
411 static void
412 g_uzip_start(struct bio *bp)
413 {
414 	struct g_provider *pp;
415 	struct g_geom *gp;
416 	struct g_uzip_softc *sc;
417 
418 	pp = bp->bio_to;
419 	gp = pp->geom;
420 
421 	DPRINTF(GUZ_DBG_IO, ("%s/%s: %p: cmd=%d, offset=%jd, length=%jd, "
422 	    "buffer=%p\n", __func__, gp->name, bp, bp->bio_cmd,
423 	    (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length, bp->bio_data));
424 
425 	sc = gp->softc;
426 	sc->req_total++;
427 
428 	if (bp->bio_cmd != BIO_READ) {
429 		g_io_deliver(bp, EOPNOTSUPP);
430 		return;
431 	}
432 
433 	bp->bio_resid = bp->bio_length;
434 	bp->bio_completed = 0;
435 
436 	g_uzip_request(gp, bp);
437 }
438 
439 static void
440 g_uzip_orphan(struct g_consumer *cp)
441 {
442 	struct g_geom *gp;
443 
444 	g_trace(G_T_TOPOLOGY, "%s(%p/%s)", __func__, cp, cp->provider->name);
445 	g_topology_assert();
446 
447 	gp = cp->geom;
448 	g_uzip_softc_free(gp->softc, gp);
449 	gp->softc = NULL;
450 	g_wither_geom(gp, ENXIO);
451 }
452 
453 static int
454 g_uzip_access(struct g_provider *pp, int dr, int dw, int de)
455 {
456 	struct g_geom *gp;
457 	struct g_consumer *cp;
458 
459 	gp = pp->geom;
460 	cp = LIST_FIRST(&gp->consumer);
461 	KASSERT (cp != NULL, ("g_uzip_access but no consumer"));
462 
463 	if (cp->acw + dw > 0)
464 		return (EROFS);
465 
466 	return (g_access(cp, dr, dw, de));
467 }
468 
469 static void
470 g_uzip_spoiled(struct g_consumer *cp)
471 {
472 	struct g_geom *gp;
473 
474 	gp = cp->geom;
475 	g_trace(G_T_TOPOLOGY, "%s(%p/%s)", __func__, cp, gp->name);
476 	g_topology_assert();
477 
478 	g_uzip_softc_free(gp->softc, gp);
479 	gp->softc = NULL;
480 	g_wither_geom(gp, ENXIO);
481 }
482 
483 static int
484 g_uzip_parse_toc(struct g_uzip_softc *sc, struct g_provider *pp,
485     struct g_geom *gp)
486 {
487 	uint32_t i, j, backref_to;
488 	uint64_t max_offset, min_offset;
489 
490 	min_offset = sizeof(struct cloop_header) +
491 	    (sc->nblocks + 1) * sizeof(uint64_t);
492 	max_offset = sc->toc[0].offset - 1;
493 	for (i = 0; i < sc->nblocks; i++) {
494 		/* First do some bounds checking */
495 		if ((sc->toc[i].offset < min_offset) ||
496 		    (sc->toc[i].offset > pp->mediasize)) {
497 			goto error_offset;
498 		}
499 		DPRINTF_BLK(GUZ_DBG_IO, i, ("%s: cluster #%u "
500 		    "sc->toc[i].offset=%ju max_offset=%ju\n", gp->name,
501 		    (u_int)i, (uintmax_t)sc->toc[i].offset,
502 		    (uintmax_t)max_offset));
503 		backref_to = BLEN_UNDEF;
504 		if (sc->toc[i].offset < max_offset) {
505 			/*
506 			 * For the backref'ed blocks search already parsed
507 			 * TOC entries for the matching offset and copy the
508 			 * size from matched entry.
509 			 */
510 			for (j = 0; j <= i; j++) {
511                                 if (sc->toc[j].offset == sc->toc[i].offset &&
512 				    !BLK_IS_NIL(sc, j)) {
513                                         break;
514                                 }
515                                 if (j != i) {
516 					continue;
517 				}
518 				DPRINTF(GUZ_DBG_ERR, ("%s: cannot match "
519 				    "backref'ed offset at cluster #%u\n",
520 				    gp->name, i));
521 				return (-1);
522 			}
523 			sc->toc[i].blen = sc->toc[j].blen;
524 			backref_to = j;
525 		} else {
526 			/*
527 			 * For the "normal blocks" seek forward until we hit
528 			 * block whose offset is larger than ours and assume
529 			 * it's going to be the next one.
530 			 */
531 			for (j = i + 1; j < sc->nblocks; j++) {
532 				if (sc->toc[j].offset > max_offset) {
533 					break;
534 				}
535 			}
536 			sc->toc[i].blen = sc->toc[j].offset -
537 			    sc->toc[i].offset;
538 			if (BLK_ENDS(sc, i) > pp->mediasize) {
539 				DPRINTF(GUZ_DBG_ERR, ("%s: cluster #%u "
540 				    "extends past media boundary (%ju > %ju)\n",
541 				    gp->name, (u_int)i,
542 				    (uintmax_t)BLK_ENDS(sc, i),
543 				    (intmax_t)pp->mediasize));
544 				return (-1);
545 			}
546 			KASSERT(max_offset <= sc->toc[i].offset, (
547 			    "%s: max_offset is incorrect: %ju",
548 			    gp->name, (uintmax_t)max_offset));
549 			max_offset = BLK_ENDS(sc, i) - 1;
550 		}
551 		DPRINTF_BLK(GUZ_DBG_TOC, i, ("%s: cluster #%u, original %u "
552 		    "bytes, in %u bytes", gp->name, i, sc->blksz,
553 		    sc->toc[i].blen));
554 		if (backref_to != BLEN_UNDEF) {
555 			DPRINTF_BLK(GUZ_DBG_TOC, i, (" (->#%u)",
556 			    (u_int)backref_to));
557 		}
558 		DPRINTF_BLK(GUZ_DBG_TOC, i, ("\n"));
559 	}
560 	return (0);
561 
562 error_offset:
563 	DPRINTF(GUZ_DBG_ERR, ("%s: cluster #%u: invalid offset %ju, "
564 	    "min_offset=%ju mediasize=%jd\n", gp->name, (u_int)i,
565 	    sc->toc[i].offset, min_offset, pp->mediasize));
566 	return (-1);
567 }
568 
569 static struct g_geom *
570 g_uzip_taste(struct g_class *mp, struct g_provider *pp, int flags)
571 {
572 	int error;
573 	uint32_t i, total_offsets, offsets_read, blk;
574 	void *buf;
575 	struct cloop_header *header;
576 	struct g_consumer *cp;
577 	struct g_geom *gp;
578 	struct g_provider *pp2;
579 	struct g_uzip_softc *sc;
580 	enum {
581 		G_UZIP = 1,
582 		G_ULZMA
583 	} type;
584 
585 	g_trace(G_T_TOPOLOGY, "%s(%s,%s)", __func__, mp->name, pp->name);
586 	g_topology_assert();
587 
588 	/* Skip providers that are already open for writing. */
589 	if (pp->acw > 0)
590 		return (NULL);
591 
592 	buf = NULL;
593 
594 	/*
595 	 * Create geom instance.
596 	 */
597 	gp = g_new_geomf(mp, "%s.uzip", pp->name);
598 	cp = g_new_consumer(gp);
599 	error = g_attach(cp, pp);
600 	if (error == 0)
601 		error = g_access(cp, 1, 0, 0);
602 	if (error) {
603 		goto e1;
604 	}
605 	g_topology_unlock();
606 
607 	/*
608 	 * Read cloop header, look for CLOOP magic, perform
609 	 * other validity checks.
610 	 */
611 	DPRINTF(GUZ_DBG_INFO, ("%s: media sectorsize %u, mediasize %jd\n",
612 	    gp->name, pp->sectorsize, (intmax_t)pp->mediasize));
613 	buf = g_read_data(cp, 0, pp->sectorsize, NULL);
614 	if (buf == NULL)
615 		goto e2;
616 	header = (struct cloop_header *) buf;
617 	if (strncmp(header->magic, CLOOP_MAGIC_START,
618 	    sizeof(CLOOP_MAGIC_START) - 1) != 0) {
619 		DPRINTF(GUZ_DBG_ERR, ("%s: no CLOOP magic\n", gp->name));
620 		goto e3;
621 	}
622 
623 	switch (header->magic[CLOOP_OFS_COMPR]) {
624 	case CLOOP_COMP_LZMA:
625 	case CLOOP_COMP_LZMA_DDP:
626 		type = G_ULZMA;
627 		if (header->magic[CLOOP_OFS_VERSN] < CLOOP_MINVER_LZMA) {
628 			DPRINTF(GUZ_DBG_ERR, ("%s: image version too old\n",
629 			    gp->name));
630 			goto e3;
631 		}
632 		DPRINTF(GUZ_DBG_INFO, ("%s: GEOM_UZIP_LZMA image found\n",
633 		    gp->name));
634 		break;
635 	case CLOOP_COMP_LIBZ:
636 	case CLOOP_COMP_LIBZ_DDP:
637 		type = G_UZIP;
638 		if (header->magic[CLOOP_OFS_VERSN] < CLOOP_MINVER_ZLIB) {
639 			DPRINTF(GUZ_DBG_ERR, ("%s: image version too old\n",
640 			    gp->name));
641 			goto e3;
642 		}
643 		DPRINTF(GUZ_DBG_INFO, ("%s: GEOM_UZIP_ZLIB image found\n",
644 		    gp->name));
645 		break;
646 	default:
647 		DPRINTF(GUZ_DBG_ERR, ("%s: unsupported image type\n",
648 		    gp->name));
649                 goto e3;
650         }
651 
652 	/*
653 	 * Initialize softc and read offsets.
654 	 */
655 	sc = malloc(sizeof(*sc), M_GEOM_UZIP, M_WAITOK | M_ZERO);
656 	gp->softc = sc;
657 	sc->blksz = ntohl(header->blksz);
658 	sc->nblocks = ntohl(header->nblocks);
659 	if (sc->blksz % 512 != 0) {
660 		printf("%s: block size (%u) should be multiple of 512.\n",
661 		    gp->name, sc->blksz);
662 		goto e4;
663 	}
664 	if (sc->blksz > MAX_BLKSZ) {
665 		printf("%s: block size (%u) should not be larger than %d.\n",
666 		    gp->name, sc->blksz, MAX_BLKSZ);
667 	}
668 	total_offsets = sc->nblocks + 1;
669 	if (sizeof(struct cloop_header) +
670 	    total_offsets * sizeof(uint64_t) > pp->mediasize) {
671 		printf("%s: media too small for %u blocks\n",
672 		    gp->name, sc->nblocks);
673 		goto e4;
674 	}
675 	sc->toc = malloc(total_offsets * sizeof(struct g_uzip_blk),
676 	    M_GEOM_UZIP, M_WAITOK | M_ZERO);
677 	offsets_read = MIN(total_offsets,
678 	    (pp->sectorsize - sizeof(*header)) / sizeof(uint64_t));
679 	for (i = 0; i < offsets_read; i++) {
680 		sc->toc[i].offset = be64toh(((uint64_t *) (header + 1))[i]);
681 		sc->toc[i].blen = BLEN_UNDEF;
682 	}
683 	DPRINTF(GUZ_DBG_INFO, ("%s: %u offsets in the first sector\n",
684 	       gp->name, offsets_read));
685 	for (blk = 1; offsets_read < total_offsets; blk++) {
686 		uint32_t nread;
687 
688 		free(buf, M_GEOM);
689 		buf = g_read_data(
690 		    cp, blk * pp->sectorsize, pp->sectorsize, NULL);
691 		if (buf == NULL)
692 			goto e5;
693 		nread = MIN(total_offsets - offsets_read,
694 		     pp->sectorsize / sizeof(uint64_t));
695 		DPRINTF(GUZ_DBG_TOC, ("%s: %u offsets read from sector %d\n",
696 		    gp->name, nread, blk));
697 		for (i = 0; i < nread; i++) {
698 			sc->toc[offsets_read + i].offset =
699 			    be64toh(((uint64_t *) buf)[i]);
700 			sc->toc[offsets_read + i].blen = BLEN_UNDEF;
701 		}
702 		offsets_read += nread;
703 	}
704 	free(buf, M_GEOM);
705 	buf = NULL;
706 	offsets_read -= 1;
707 	DPRINTF(GUZ_DBG_INFO, ("%s: done reading %u block offsets from %u "
708 	    "sectors\n", gp->name, offsets_read, blk));
709 	if (sc->nblocks != offsets_read) {
710 		DPRINTF(GUZ_DBG_ERR, ("%s: read %s offsets than expected "
711 		    "blocks\n", gp->name,
712 		    sc->nblocks < offsets_read ? "more" : "less"));
713 		goto e5;
714 	}
715 	/*
716 	 * "Fake" last+1 block, to make it easier for the TOC parser to
717 	 * iterate without making the last element a special case.
718 	 */
719 	sc->toc[sc->nblocks].offset = pp->mediasize;
720 	/* Massage TOC (table of contents), make sure it is sound */
721 	if (g_uzip_parse_toc(sc, pp, gp) != 0) {
722 		DPRINTF(GUZ_DBG_ERR, ("%s: TOC error\n", gp->name));
723 		goto e5;
724 	}
725 	mtx_init(&sc->last_mtx, "geom_uzip cache", NULL, MTX_DEF);
726 	mtx_init(&sc->queue_mtx, "geom_uzip wrkthread", NULL, MTX_DEF);
727 	bioq_init(&sc->bio_queue);
728 	sc->last_blk = -1;
729 	sc->last_buf = malloc(sc->blksz, M_GEOM_UZIP, M_WAITOK);
730 	sc->req_total = 0;
731 	sc->req_cached = 0;
732 
733 	if (type == G_UZIP) {
734 		sc->dcp = g_uzip_zlib_ctor(sc->blksz);
735 	} else {
736 		sc->dcp = g_uzip_lzma_ctor(sc->blksz);
737 	}
738 	if (sc->dcp == NULL) {
739 		goto e6;
740 	}
741 
742 	sc->uzip_do = &g_uzip_do;
743 
744 	error = kproc_create(g_uzip_wrkthr, sc, &sc->procp, 0, 0, "%s",
745 	    gp->name);
746 	if (error != 0) {
747 		goto e7;
748 	}
749 
750 	g_topology_lock();
751 	pp2 = g_new_providerf(gp, "%s", gp->name);
752 	pp2->sectorsize = 512;
753 	pp2->mediasize = (off_t)sc->nblocks * sc->blksz;
754 	pp2->stripesize = pp->stripesize;
755 	pp2->stripeoffset = pp->stripeoffset;
756 	g_error_provider(pp2, 0);
757 	g_access(cp, -1, 0, 0);
758 
759 	DPRINTF(GUZ_DBG_INFO, ("%s: taste ok (%d, %jd), (%d, %d), %x\n",
760 	    gp->name, pp2->sectorsize, (intmax_t)pp2->mediasize,
761 	    pp2->stripeoffset, pp2->stripesize, pp2->flags));
762 	DPRINTF(GUZ_DBG_INFO, ("%s: %u x %u blocks\n", gp->name, sc->nblocks,
763 	    sc->blksz));
764 	return (gp);
765 
766 e7:
767 	sc->dcp->free(sc->dcp);
768 e6:
769 	free(sc->last_buf, M_GEOM);
770 	mtx_destroy(&sc->queue_mtx);
771 	mtx_destroy(&sc->last_mtx);
772 e5:
773 	free(sc->toc, M_GEOM);
774 e4:
775 	free(gp->softc, M_GEOM_UZIP);
776 e3:
777 	if (buf != NULL) {
778 		free(buf, M_GEOM);
779 	}
780 e2:
781 	g_topology_lock();
782 	g_access(cp, -1, 0, 0);
783 e1:
784 	g_detach(cp);
785 	g_destroy_consumer(cp);
786 	g_destroy_geom(gp);
787 
788 	return (NULL);
789 }
790 
791 static int
792 g_uzip_destroy_geom(struct gctl_req *req, struct g_class *mp, struct g_geom *gp)
793 {
794 	struct g_provider *pp;
795 
796 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, gp->name);
797 	g_topology_assert();
798 
799 	if (gp->softc == NULL) {
800 		DPRINTF(GUZ_DBG_ERR, ("%s(%s): gp->softc == NULL\n", __func__,
801 		    gp->name));
802 		return (ENXIO);
803 	}
804 
805 	KASSERT(gp != NULL, ("NULL geom"));
806 	pp = LIST_FIRST(&gp->provider);
807 	KASSERT(pp != NULL, ("NULL provider"));
808 	if (pp->acr > 0 || pp->acw > 0 || pp->ace > 0)
809 		return (EBUSY);
810 
811 	g_uzip_softc_free(gp->softc, gp);
812 	gp->softc = NULL;
813 	g_wither_geom(gp, ENXIO);
814 
815 	return (0);
816 }
817 
818 static struct g_class g_uzip_class = {
819 	.name = UZIP_CLASS_NAME,
820 	.version = G_VERSION,
821 	.taste = g_uzip_taste,
822 	.destroy_geom = g_uzip_destroy_geom,
823 
824 	.start = g_uzip_start,
825 	.orphan = g_uzip_orphan,
826 	.access = g_uzip_access,
827 	.spoiled = g_uzip_spoiled,
828 };
829 
830 DECLARE_GEOM_CLASS(g_uzip_class, g_uzip);
831 MODULE_DEPEND(g_uzip, zlib, 1, 1, 1);
832