xref: /freebsd/sys/geom/uzip/g_uzip.c (revision 443a0f85)
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 MALLOC_DEFINE(M_GEOM_UZIP, "geom_uzip", "GEOM UZIP data structures");
55 
56 FEATURE(geom_uzip, "GEOM read-only compressed disks support");
57 
58 struct g_uzip_blk {
59         uint64_t offset;
60         uint32_t blen;
61 #define BLEN_UNDEF      UINT32_MAX
62 };
63 
64 #ifndef ABS
65 #define	ABS(a)			((a) < 0 ? -(a) : (a))
66 #endif
67 
68 #define BLK_IN_RANGE(mcn, bcn, ilen)	\
69     (((bcn) != BLEN_UNDEF) && ( \
70 	((ilen) >= 0 && (mcn >= bcn) && (mcn <= ((intmax_t)(bcn) + (ilen)))) || \
71 	((ilen) < 0 && (mcn <= bcn) && (mcn >= ((intmax_t)(bcn) + (ilen)))) \
72     ))
73 
74 #ifdef GEOM_UZIP_DEBUG
75 # define GEOM_UZIP_DBG_DEFAULT	3
76 #else
77 # define GEOM_UZIP_DBG_DEFAULT	0
78 #endif
79 
80 #define	GUZ_DBG_ERR	1
81 #define	GUZ_DBG_INFO	2
82 #define	GUZ_DBG_IO	3
83 #define	GUZ_DBG_TOC	4
84 
85 SYSCTL_DECL(_kern_geom);
86 SYSCTL_NODE(_kern_geom, OID_AUTO, uzip, CTLFLAG_RW, 0, "GEOM_UZIP stuff");
87 static u_int g_uzip_debug = GEOM_UZIP_DBG_DEFAULT;
88 SYSCTL_UINT(_kern_geom_uzip, OID_AUTO, debug, CTLFLAG_RWTUN, &g_uzip_debug, 0,
89     "Debug level (0-4)");
90 static u_int g_uzip_debug_block = BLEN_UNDEF;
91 SYSCTL_UINT(_kern_geom_uzip, OID_AUTO, debug_block, CTLFLAG_RWTUN,
92     &g_uzip_debug_block, 0, "Debug operations around specific cluster#");
93 
94 #define	DPRINTF(lvl, a)		\
95 	if ((lvl) <= g_uzip_debug) { \
96 		printf a; \
97 	}
98 #define	DPRINTF_BLK(lvl, cn, a)	\
99 	if ((lvl) <= g_uzip_debug || \
100 	    BLK_IN_RANGE(cn, g_uzip_debug_block, 8) || \
101 	    BLK_IN_RANGE(cn, g_uzip_debug_block, -8)) { \
102 		printf a; \
103 	}
104 #define	DPRINTF_BRNG(lvl, bcn, ecn, a) \
105 	if (bcn >= ecn) { \
106 		printf("DPRINTF_BRNG: invalid range (%ju, %ju), BUG BUG " \
107 		    "BUG!\n", (uintmax_t)bcn, (uintmax_t)ecn); \
108 	} else if (((lvl) <= g_uzip_debug) || \
109 	    BLK_IN_RANGE(g_uzip_debug_block, bcn, \
110 	     (intmax_t)ecn - (intmax_t)bcn)) { \
111 		printf a; \
112 	}
113 
114 #define	UZIP_CLASS_NAME	"UZIP"
115 
116 /*
117  * Maximum allowed valid block size (to prevent foot-shooting)
118  */
119 #define	MAX_BLKSZ	(MAXPHYS)
120 
121 static char CLOOP_MAGIC_START[] = "#!/bin/sh\n";
122 
123 static void g_uzip_read_done(struct bio *bp);
124 static void g_uzip_do(struct g_uzip_softc *, struct bio *bp);
125 
126 static void
127 g_uzip_softc_free(struct g_uzip_softc *sc, struct g_geom *gp)
128 {
129 
130 	if (gp != NULL) {
131 		DPRINTF(GUZ_DBG_INFO, ("%s: %d requests, %d cached\n",
132 		    gp->name, sc->req_total, sc->req_cached));
133 	}
134 
135 	mtx_lock(&sc->queue_mtx);
136 	sc->wrkthr_flags |= GUZ_SHUTDOWN;
137 	wakeup(sc);
138 	while (!(sc->wrkthr_flags & GUZ_EXITING)) {
139 		msleep(sc->procp, &sc->queue_mtx, PRIBIO, "guzfree",
140 		    hz / 10);
141 	}
142 	mtx_unlock(&sc->queue_mtx);
143 
144 	sc->dcp->free(sc->dcp);
145 	free(sc->toc, M_GEOM_UZIP);
146 	mtx_destroy(&sc->queue_mtx);
147 	mtx_destroy(&sc->last_mtx);
148 	free(sc->last_buf, M_GEOM_UZIP);
149 	free(sc, M_GEOM_UZIP);
150 }
151 
152 static int
153 g_uzip_cached(struct g_geom *gp, struct bio *bp)
154 {
155 	struct g_uzip_softc *sc;
156 	off_t ofs;
157 	size_t blk, blkofs, usz;
158 
159 	sc = gp->softc;
160 	ofs = bp->bio_offset + bp->bio_completed;
161 	blk = ofs / sc->blksz;
162 	mtx_lock(&sc->last_mtx);
163 	if (blk == sc->last_blk) {
164 		blkofs = ofs % sc->blksz;
165 		usz = sc->blksz - blkofs;
166 		if (bp->bio_resid < usz)
167 			usz = bp->bio_resid;
168 		memcpy(bp->bio_data + bp->bio_completed, sc->last_buf + blkofs,
169 		    usz);
170 		sc->req_cached++;
171 		mtx_unlock(&sc->last_mtx);
172 
173 		DPRINTF(GUZ_DBG_IO, ("%s/%s: %p: offset=%jd: got %jd bytes "
174 		    "from cache\n", __func__, gp->name, bp, (intmax_t)ofs,
175 		    (intmax_t)usz));
176 
177 		bp->bio_completed += usz;
178 		bp->bio_resid -= usz;
179 
180 		if (bp->bio_resid == 0) {
181 			g_io_deliver(bp, 0);
182 			return (1);
183 		}
184 	} else
185 		mtx_unlock(&sc->last_mtx);
186 
187 	return (0);
188 }
189 
190 #define BLK_ENDS(sc, bi)	((sc)->toc[(bi)].offset + \
191     (sc)->toc[(bi)].blen)
192 
193 #define BLK_IS_CONT(sc, bi)	(BLK_ENDS((sc), (bi) - 1) == \
194     (sc)->toc[(bi)].offset)
195 #define	BLK_IS_NIL(sc, bi)	((sc)->toc[(bi)].blen == 0)
196 
197 #define TOFF_2_BOFF(sc, pp, bi)	    ((sc)->toc[(bi)].offset - \
198     (sc)->toc[(bi)].offset % (pp)->sectorsize)
199 #define TLEN_2_BLEN(sc, pp, bp, ei) ((BLK_ENDS((sc), (ei)) - \
200     (bp)->bio_offset + (pp)->sectorsize - 1) / \
201     (pp)->sectorsize * (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 = (ofs + bp->bio_resid + sc->blksz - 1) / 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 
278 		end_blk--;
279 	}
280 
281 	bp2->bio_data = malloc(bp2->bio_length, M_GEOM_UZIP, M_NOWAIT);
282 	if (bp2->bio_data == NULL) {
283 		g_destroy_bio(bp2);
284 		g_io_deliver(bp, ENOMEM);
285 		return (1);
286 	}
287 
288 	DPRINTF_BRNG(GUZ_DBG_IO, start_blk, end_blk, ("%s/%s: %p: "
289 	    "reading %jd bytes from offset %jd\n", __func__, gp->name, bp,
290 	    (intmax_t)bp2->bio_length, (intmax_t)bp2->bio_offset));
291 
292 	g_io_request(bp2, cp);
293 	return (0);
294 }
295 
296 static void
297 g_uzip_read_done(struct bio *bp)
298 {
299 	struct bio *bp2;
300 	struct g_geom *gp;
301 	struct g_uzip_softc *sc;
302 
303 	bp2 = bp->bio_parent;
304 	gp = bp2->bio_to->geom;
305 	sc = gp->softc;
306 
307 	mtx_lock(&sc->queue_mtx);
308 	bioq_disksort(&sc->bio_queue, bp);
309 	mtx_unlock(&sc->queue_mtx);
310 	wakeup(sc);
311 }
312 
313 static void
314 g_uzip_do(struct g_uzip_softc *sc, struct bio *bp)
315 {
316 	struct bio *bp2;
317 	struct g_provider *pp;
318 	struct g_consumer *cp;
319 	struct g_geom *gp;
320 	char *data, *data2;
321 	off_t ofs;
322 	size_t blk, blkofs, len, ulen, firstblk;
323 	int err;
324 
325 	bp2 = bp->bio_parent;
326 	gp = bp2->bio_to->geom;
327 
328 	cp = LIST_FIRST(&gp->consumer);
329 	pp = cp->provider;
330 
331 	bp2->bio_error = bp->bio_error;
332 	if (bp2->bio_error != 0)
333 		goto done;
334 
335 	/* Make sure there's forward progress. */
336 	if (bp->bio_completed == 0) {
337 		bp2->bio_error = ECANCELED;
338 		goto done;
339 	}
340 
341 	ofs = bp2->bio_offset + bp2->bio_completed;
342 	firstblk = blk = ofs / sc->blksz;
343 	blkofs = ofs % sc->blksz;
344 	data = bp->bio_data + sc->toc[blk].offset % pp->sectorsize;
345 	data2 = bp2->bio_data + bp2->bio_completed;
346 	while (bp->bio_completed && bp2->bio_resid) {
347 		if (blk > firstblk && !BLK_IS_CONT(sc, blk)) {
348 			DPRINTF_BLK(GUZ_DBG_IO, blk, ("%s/%s: %p: backref'ed "
349 			    "cluster #%u requested, looping around\n",
350 			    __func__, gp->name, bp2, (u_int)blk));
351 			goto done;
352 		}
353 		ulen = MIN(sc->blksz - blkofs, bp2->bio_resid);
354 		len = sc->toc[blk].blen;
355 		DPRINTF(GUZ_DBG_IO, ("%s/%s: %p/%ju: data2=%p, ulen=%u, "
356 		    "data=%p, len=%u\n", __func__, gp->name, gp,
357 		    bp->bio_completed, data2, (u_int)ulen, data, (u_int)len));
358 		if (len == 0) {
359 			/* All zero block: no cache update */
360 			bzero(data2, ulen);
361 		} else if (len <= bp->bio_completed) {
362 			mtx_lock(&sc->last_mtx);
363 			err = sc->dcp->decompress(sc->dcp, gp->name, data,
364 			    len, sc->last_buf);
365 			if (err != 0) {
366 				sc->last_blk = -1;
367 				mtx_unlock(&sc->last_mtx);
368 				bp2->bio_error = EILSEQ;
369 				DPRINTF(GUZ_DBG_ERR, ("%s/%s: decompress"
370 				    "(%p) failed\n", __func__, gp->name,
371 				    sc->dcp));
372 				goto done;
373 			}
374 			sc->last_blk = blk;
375 			memcpy(data2, sc->last_buf + blkofs, ulen);
376 			mtx_unlock(&sc->last_mtx);
377 			err = sc->dcp->rewind(sc->dcp, gp->name);
378 			if (err != 0) {
379 				bp2->bio_error = EILSEQ;
380 				DPRINTF(GUZ_DBG_ERR, ("%s/%s: rewind(%p) "
381 				    "failed\n", __func__, gp->name, sc->dcp));
382 				goto done;
383 			}
384 			data += len;
385 		} else
386 			break;
387 
388 		data2 += ulen;
389 		bp2->bio_completed += ulen;
390 		bp2->bio_resid -= ulen;
391 		bp->bio_completed -= len;
392 		blkofs = 0;
393 		blk++;
394 	}
395 
396 done:
397 	/* Finish processing the request. */
398 	free(bp->bio_data, M_GEOM_UZIP);
399 	g_destroy_bio(bp);
400 	if (bp2->bio_error != 0 || bp2->bio_resid == 0)
401 		g_io_deliver(bp2, bp2->bio_error);
402 	else
403 		g_uzip_request(gp, bp2);
404 }
405 
406 static void
407 g_uzip_start(struct bio *bp)
408 {
409 	struct g_provider *pp;
410 	struct g_geom *gp;
411 	struct g_uzip_softc *sc;
412 
413 	pp = bp->bio_to;
414 	gp = pp->geom;
415 
416 	DPRINTF(GUZ_DBG_IO, ("%s/%s: %p: cmd=%d, offset=%jd, length=%jd, "
417 	    "buffer=%p\n", __func__, gp->name, bp, bp->bio_cmd,
418 	    (intmax_t)bp->bio_offset, (intmax_t)bp->bio_length, bp->bio_data));
419 
420 	sc = gp->softc;
421 	sc->req_total++;
422 
423 	if (bp->bio_cmd != BIO_READ) {
424 		g_io_deliver(bp, EOPNOTSUPP);
425 		return;
426 	}
427 
428 	bp->bio_resid = bp->bio_length;
429 	bp->bio_completed = 0;
430 
431 	g_uzip_request(gp, bp);
432 }
433 
434 static void
435 g_uzip_orphan(struct g_consumer *cp)
436 {
437 	struct g_geom *gp;
438 
439 	g_trace(G_T_TOPOLOGY, "%s(%p/%s)", __func__, cp, cp->provider->name);
440 	g_topology_assert();
441 
442 	gp = cp->geom;
443 	g_uzip_softc_free(gp->softc, gp);
444 	gp->softc = NULL;
445 	g_wither_geom(gp, ENXIO);
446 }
447 
448 static int
449 g_uzip_access(struct g_provider *pp, int dr, int dw, int de)
450 {
451 	struct g_geom *gp;
452 	struct g_consumer *cp;
453 
454 	gp = pp->geom;
455 	cp = LIST_FIRST(&gp->consumer);
456 	KASSERT (cp != NULL, ("g_uzip_access but no consumer"));
457 
458 	if (cp->acw + dw > 0)
459 		return (EROFS);
460 
461 	return (g_access(cp, dr, dw, de));
462 }
463 
464 static void
465 g_uzip_spoiled(struct g_consumer *cp)
466 {
467 	struct g_geom *gp;
468 
469 	gp = cp->geom;
470 	g_trace(G_T_TOPOLOGY, "%s(%p/%s)", __func__, cp, gp->name);
471 	g_topology_assert();
472 
473 	g_uzip_softc_free(gp->softc, gp);
474 	gp->softc = NULL;
475 	g_wither_geom(gp, ENXIO);
476 }
477 
478 static int
479 g_uzip_parse_toc(struct g_uzip_softc *sc, struct g_provider *pp,
480     struct g_geom *gp)
481 {
482 	uint32_t i, j, backref_to;
483 	uint64_t max_offset, min_offset;
484 
485 	min_offset = sizeof(struct cloop_header) +
486 	    (sc->nblocks + 1) * sizeof(uint64_t);
487 	max_offset = sc->toc[0].offset - 1;
488 	for (i = 0; i < sc->nblocks; i++) {
489 		/* First do some bounds checking */
490 		if ((sc->toc[i].offset < min_offset) ||
491 		    (sc->toc[i].offset >= pp->mediasize)) {
492 			goto error_offset;
493 		}
494 		DPRINTF_BLK(GUZ_DBG_IO, i, ("%s: cluster #%u "
495 		    "sc->toc[i].offset=%ju max_offset=%ju\n", gp->name,
496 		    (u_int)i, (uintmax_t)sc->toc[i].offset,
497 		    (uintmax_t)max_offset));
498 		backref_to = BLEN_UNDEF;
499 		if (sc->toc[i].offset < max_offset) {
500 			/*
501 			 * For the backref'ed blocks search already parsed
502 			 * TOC entries for the matching offset and copy the
503 			 * size from matched entry.
504 			 */
505 			for (j = 0; j <= i; j++) {
506                                 if (sc->toc[j].offset == sc->toc[i].offset &&
507 				    !BLK_IS_NIL(sc, j)) {
508                                         break;
509                                 }
510                                 if (j != i) {
511 					continue;
512 				}
513 				DPRINTF(GUZ_DBG_ERR, ("%s: cannot match "
514 				    "backref'ed offset at cluster #%u\n",
515 				    gp->name, i));
516 				return (-1);
517 			}
518 			sc->toc[i].blen = sc->toc[j].blen;
519 			backref_to = j;
520 		} else {
521 			/*
522 			 * For the "normal blocks" seek forward until we hit
523 			 * block whose offset is larger than ours and assume
524 			 * it's going to be the next one.
525 			 */
526 			for (j = i + 1; j < sc->nblocks; j++) {
527 				if (sc->toc[j].offset > max_offset) {
528 					break;
529 				}
530 			}
531 			sc->toc[i].blen = sc->toc[j].offset -
532 			    sc->toc[i].offset;
533 			if (BLK_ENDS(sc, i) > pp->mediasize) {
534 				DPRINTF(GUZ_DBG_ERR, ("%s: cluster #%u "
535 				    "extends past media boundary (%ju > %ju)\n",
536 				    gp->name, (u_int)i,
537 				    (uintmax_t)BLK_ENDS(sc, i),
538 				    (intmax_t)pp->mediasize));
539 				return (-1);
540 			}
541 			KASSERT(max_offset <= sc->toc[i].offset, (
542 			    "%s: max_offset is incorrect: %ju",
543 			    gp->name, (uintmax_t)max_offset));
544 			max_offset = BLK_ENDS(sc, i) - 1;
545 		}
546 		DPRINTF_BLK(GUZ_DBG_TOC, i, ("%s: cluster #%u, original %u "
547 		    "bytes, in %u bytes", gp->name, i, sc->blksz,
548 		    sc->toc[i].blen));
549 		if (backref_to != BLEN_UNDEF) {
550 			DPRINTF_BLK(GUZ_DBG_TOC, i, (" (->#%u)",
551 			    (u_int)backref_to));
552 		}
553 		DPRINTF_BLK(GUZ_DBG_TOC, i, ("\n"));
554 	}
555 	return (0);
556 
557 error_offset:
558 	DPRINTF(GUZ_DBG_ERR, ("%s: cluster #%u: invalid offset %ju, "
559 	    "min_offset=%ju mediasize=%jd\n", gp->name, (u_int)i,
560 	    sc->toc[i].offset, min_offset, pp->mediasize));
561 	return (-1);
562 }
563 
564 static struct g_geom *
565 g_uzip_taste(struct g_class *mp, struct g_provider *pp, int flags)
566 {
567 	int error;
568 	uint32_t i, total_offsets, offsets_read, blk;
569 	void *buf;
570 	struct cloop_header *header;
571 	struct g_consumer *cp;
572 	struct g_geom *gp;
573 	struct g_provider *pp2;
574 	struct g_uzip_softc *sc;
575 	enum {
576 		GEOM_UZIP = 1,
577 		GEOM_ULZMA
578 	} type;
579 
580 	g_trace(G_T_TOPOLOGY, "%s(%s,%s)", __func__, mp->name, pp->name);
581 	g_topology_assert();
582 
583 	/* Skip providers that are already open for writing. */
584 	if (pp->acw > 0)
585 		return (NULL);
586 
587 	buf = NULL;
588 
589 	/*
590 	 * Create geom instance.
591 	 */
592 	gp = g_new_geomf(mp, "%s.uzip", pp->name);
593 	cp = g_new_consumer(gp);
594 	error = g_attach(cp, pp);
595 	if (error == 0)
596 		error = g_access(cp, 1, 0, 0);
597 	if (error) {
598 		goto e1;
599 	}
600 	g_topology_unlock();
601 
602 	/*
603 	 * Read cloop header, look for CLOOP magic, perform
604 	 * other validity checks.
605 	 */
606 	DPRINTF(GUZ_DBG_INFO, ("%s: media sectorsize %u, mediasize %jd\n",
607 	    gp->name, pp->sectorsize, (intmax_t)pp->mediasize));
608 	buf = g_read_data(cp, 0, pp->sectorsize, NULL);
609 	if (buf == NULL)
610 		goto e2;
611 	header = (struct cloop_header *) buf;
612 	if (strncmp(header->magic, CLOOP_MAGIC_START,
613 	    sizeof(CLOOP_MAGIC_START) - 1) != 0) {
614 		DPRINTF(GUZ_DBG_ERR, ("%s: no CLOOP magic\n", gp->name));
615 		goto e3;
616 	}
617 
618 	switch (header->magic[CLOOP_OFS_COMPR]) {
619 	case CLOOP_COMP_LZMA:
620 	case CLOOP_COMP_LZMA_DDP:
621 		type = GEOM_ULZMA;
622 		if (header->magic[CLOOP_OFS_VERSN] < CLOOP_MINVER_LZMA) {
623 			DPRINTF(GUZ_DBG_ERR, ("%s: image version too old\n",
624 			    gp->name));
625 			goto e3;
626 		}
627 		DPRINTF(GUZ_DBG_INFO, ("%s: GEOM_UZIP_LZMA image found\n",
628 		    gp->name));
629 		break;
630 	case CLOOP_COMP_LIBZ:
631 	case CLOOP_COMP_LIBZ_DDP:
632 		type = GEOM_UZIP;
633 		if (header->magic[CLOOP_OFS_VERSN] < CLOOP_MINVER_ZLIB) {
634 			DPRINTF(GUZ_DBG_ERR, ("%s: image version too old\n",
635 			    gp->name));
636 			goto e3;
637 		}
638 		DPRINTF(GUZ_DBG_INFO, ("%s: GEOM_UZIP_ZLIB image found\n",
639 		    gp->name));
640 		break;
641 	default:
642 		DPRINTF(GUZ_DBG_ERR, ("%s: unsupported image type\n",
643 		    gp->name));
644                 goto e3;
645         }
646 
647 	/*
648 	 * Initialize softc and read offsets.
649 	 */
650 	sc = malloc(sizeof(*sc), M_GEOM_UZIP, M_WAITOK | M_ZERO);
651 	gp->softc = sc;
652 	sc->blksz = ntohl(header->blksz);
653 	sc->nblocks = ntohl(header->nblocks);
654 	if (sc->blksz % 512 != 0) {
655 		printf("%s: block size (%u) should be multiple of 512.\n",
656 		    gp->name, sc->blksz);
657 		goto e4;
658 	}
659 	if (sc->blksz > MAX_BLKSZ) {
660 		printf("%s: block size (%u) should not be larger than %d.\n",
661 		    gp->name, sc->blksz, MAX_BLKSZ);
662 	}
663 	total_offsets = sc->nblocks + 1;
664 	if (sizeof(struct cloop_header) +
665 	    total_offsets * sizeof(uint64_t) > pp->mediasize) {
666 		printf("%s: media too small for %u blocks\n",
667 		    gp->name, sc->nblocks);
668 		goto e4;
669 	}
670 	sc->toc = malloc(total_offsets * sizeof(struct g_uzip_blk),
671 	    M_GEOM_UZIP, M_WAITOK | M_ZERO);
672 	offsets_read = MIN(total_offsets,
673 	    (pp->sectorsize - sizeof(*header)) / sizeof(uint64_t));
674 	for (i = 0; i < offsets_read; i++) {
675 		sc->toc[i].offset = be64toh(((uint64_t *) (header + 1))[i]);
676 		sc->toc[i].blen = BLEN_UNDEF;
677 	}
678 	DPRINTF(GUZ_DBG_INFO, ("%s: %u offsets in the first sector\n",
679 	       gp->name, offsets_read));
680 	for (blk = 1; offsets_read < total_offsets; blk++) {
681 		uint32_t nread;
682 
683 		free(buf, M_GEOM);
684 		buf = g_read_data(
685 		    cp, blk * pp->sectorsize, pp->sectorsize, NULL);
686 		if (buf == NULL)
687 			goto e5;
688 		nread = MIN(total_offsets - offsets_read,
689 		     pp->sectorsize / sizeof(uint64_t));
690 		DPRINTF(GUZ_DBG_TOC, ("%s: %u offsets read from sector %d\n",
691 		    gp->name, nread, blk));
692 		for (i = 0; i < nread; i++) {
693 			sc->toc[offsets_read + i].offset =
694 			    be64toh(((uint64_t *) buf)[i]);
695 			sc->toc[offsets_read + i].blen = BLEN_UNDEF;
696 		}
697 		offsets_read += nread;
698 	}
699 	free(buf, M_GEOM);
700 	buf = NULL;
701 	offsets_read -= 1;
702 	DPRINTF(GUZ_DBG_INFO, ("%s: done reading %u block offsets from %u "
703 	    "sectors\n", gp->name, offsets_read, blk));
704 	if (sc->nblocks != offsets_read) {
705 		DPRINTF(GUZ_DBG_ERR, ("%s: read %s offsets than expected "
706 		    "blocks\n", gp->name,
707 		    sc->nblocks < offsets_read ? "more" : "less"));
708 		goto e5;
709 	}
710 	/* Massage TOC (table of contents), make sure it is sound */
711 	if (g_uzip_parse_toc(sc, pp, gp) != 0) {
712 		DPRINTF(GUZ_DBG_ERR, ("%s: TOC error\n", gp->name));
713 		goto e5;
714 	}
715 	mtx_init(&sc->last_mtx, "geom_uzip cache", NULL, MTX_DEF);
716 	mtx_init(&sc->queue_mtx, "geom_uzip wrkthread", NULL, MTX_DEF);
717 	bioq_init(&sc->bio_queue);
718 	sc->last_blk = -1;
719 	sc->last_buf = malloc(sc->blksz, M_GEOM_UZIP, M_WAITOK);
720 	sc->req_total = 0;
721 	sc->req_cached = 0;
722 
723 	if (type == GEOM_UZIP) {
724 		sc->dcp = g_uzip_zlib_ctor(sc->blksz);
725 	} else {
726 		sc->dcp = g_uzip_lzma_ctor(sc->blksz);
727 	}
728 	if (sc->dcp == NULL) {
729 		goto e6;
730 	}
731 
732 	sc->uzip_do = &g_uzip_do;
733 
734 	error = kproc_create(g_uzip_wrkthr, sc, &sc->procp, 0, 0, "%s",
735 	    gp->name);
736 	if (error != 0) {
737 		goto e7;
738 	}
739 
740 	g_topology_lock();
741 	pp2 = g_new_providerf(gp, "%s", gp->name);
742 	pp2->sectorsize = 512;
743 	pp2->mediasize = (off_t)sc->nblocks * sc->blksz;
744 	pp2->stripesize = pp->stripesize;
745 	pp2->stripeoffset = pp->stripeoffset;
746 	g_error_provider(pp2, 0);
747 	g_access(cp, -1, 0, 0);
748 
749 	DPRINTF(GUZ_DBG_INFO, ("%s: taste ok (%d, %jd), (%d, %d), %x\n",
750 	    gp->name, pp2->sectorsize, (intmax_t)pp2->mediasize,
751 	    pp2->stripeoffset, pp2->stripesize, pp2->flags));
752 	DPRINTF(GUZ_DBG_INFO, ("%s: %u x %u blocks\n", gp->name, sc->nblocks,
753 	    sc->blksz));
754 	return (gp);
755 
756 e7:
757 	sc->dcp->free(sc->dcp);
758 e6:
759 	free(sc->last_buf, M_GEOM);
760 	mtx_destroy(&sc->queue_mtx);
761 	mtx_destroy(&sc->last_mtx);
762 e5:
763 	free(sc->toc, M_GEOM);
764 e4:
765 	free(gp->softc, M_GEOM_UZIP);
766 e3:
767 	if (buf != NULL) {
768 		free(buf, M_GEOM);
769 	}
770 e2:
771 	g_topology_lock();
772 	g_access(cp, -1, 0, 0);
773 e1:
774 	g_detach(cp);
775 	g_destroy_consumer(cp);
776 	g_destroy_geom(gp);
777 
778 	return (NULL);
779 }
780 
781 static int
782 g_uzip_destroy_geom(struct gctl_req *req, struct g_class *mp, struct g_geom *gp)
783 {
784 	struct g_provider *pp;
785 
786 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, gp->name);
787 	g_topology_assert();
788 
789 	if (gp->softc == NULL) {
790 		DPRINTF(GUZ_DBG_ERR, ("%s(%s): gp->softc == NULL\n", __func__,
791 		    gp->name));
792 		return (ENXIO);
793 	}
794 
795 	KASSERT(gp != NULL, ("NULL geom"));
796 	pp = LIST_FIRST(&gp->provider);
797 	KASSERT(pp != NULL, ("NULL provider"));
798 	if (pp->acr > 0 || pp->acw > 0 || pp->ace > 0)
799 		return (EBUSY);
800 
801 	g_uzip_softc_free(gp->softc, gp);
802 	gp->softc = NULL;
803 	g_wither_geom(gp, ENXIO);
804 
805 	return (0);
806 }
807 
808 static struct g_class g_uzip_class = {
809 	.name = UZIP_CLASS_NAME,
810 	.version = G_VERSION,
811 	.taste = g_uzip_taste,
812 	.destroy_geom = g_uzip_destroy_geom,
813 
814 	.start = g_uzip_start,
815 	.orphan = g_uzip_orphan,
816 	.access = g_uzip_access,
817 	.spoiled = g_uzip_spoiled,
818 };
819 
820 DECLARE_GEOM_CLASS(g_uzip_class, g_uzip);
821 MODULE_DEPEND(g_uzip, zlib, 1, 1, 1);
822