xref: /illumos-gate/usr/src/uts/common/io/lofi.c (revision 2e974cb249348d85504bcae1531077d628af4c2d)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
23  *
24  * Copyright 2013 Nexenta Systems, Inc. All rights reserved.
25  * Copyright (c) 2016 Andrey Sokolov
26  * Copyright 2016 Toomas Soome <tsoome@me.com>
27  * Copyright 2019 Joyent, Inc.
28  */
29 
30 /*
31  * lofi (loopback file) driver - allows you to attach a file to a device,
32  * which can then be accessed through that device. The simple model is that
33  * you tell lofi to open a file, and then use the block device you get as
34  * you would any block device. lofi translates access to the block device
35  * into I/O on the underlying file. This is mostly useful for
36  * mounting images of filesystems.
37  *
38  * lofi is controlled through /dev/lofictl - this is the only device exported
39  * during attach, and is instance number 0. lofiadm communicates with lofi
40  * through ioctls on this device. When a file is attached to lofi, block and
41  * character devices are exported in /dev/lofi and /dev/rlofi. These devices
42  * are identified by lofi instance number, and the instance number is also used
43  * as the name in /dev/lofi.
44  *
45  * Virtual disks, or, labeled lofi, implements virtual disk support to
46  * support partition table and related tools. Such mappings will cause
47  * block and character devices to be exported in /dev/dsk and /dev/rdsk
48  * directories.
49  *
50  * To support virtual disks, the instance number space is divided to two
51  * parts, upper part for instance number and lower part for minor number
52  * space to identify partitions and slices. The virtual disk support is
53  * implemented by stacking cmlb module. For virtual disks, the partition
54  * related ioctl calls are routed to cmlb module. Compression and encryption
55  * is not supported for virtual disks.
56  *
57  * Mapped devices are tracked with state structures handled with
58  * ddi_soft_state(9F) for simplicity.
59  *
60  * A file attached to lofi is opened when attached and not closed until
61  * explicitly detached from lofi. This seems more sensible than deferring
62  * the open until the /dev/lofi device is opened, for a number of reasons.
63  * One is that any failure is likely to be noticed by the person (or script)
64  * running lofiadm. Another is that it would be a security problem if the
65  * file was replaced by another one after being added but before being opened.
66  *
67  * The only hard part about lofi is the ioctls. In order to support things
68  * like 'newfs' on a lofi device, it needs to support certain disk ioctls.
69  * So it has to fake disk geometry and partition information. More may need
70  * to be faked if your favorite utility doesn't work and you think it should
71  * (fdformat doesn't work because it really wants to know the type of floppy
72  * controller to talk to, and that didn't seem easy to fake. Or possibly even
73  * necessary, since we have mkfs_pcfs now).
74  *
75  * Normally, a lofi device cannot be detached if it is open (i.e. busy).  To
76  * support simulation of hotplug events, an optional force flag is provided.
77  * If a lofi device is open when a force detach is requested, then the
78  * underlying file is closed and any subsequent operations return EIO.  When the
79  * device is closed for the last time, it will be cleaned up at that time.  In
80  * addition, the DKIOCSTATE ioctl will return DKIO_DEV_GONE when the device is
81  * detached but not removed.
82  *
83  * If detach was requested and lofi device is not open, we will perform
84  * unmap and remove the lofi instance.
85  *
86  * If the lofi device is open and the li_cleanup is set on ioctl request,
87  * we set ls_cleanup flag to notify the cleanup is requested, and the
88  * last lofi_close will perform the unmapping and this lofi instance will be
89  * removed.
90  *
91  * If the lofi device is open and the li_force is set on ioctl request,
92  * we set ls_cleanup flag to notify the cleanup is requested,
93  * we also set ls_vp_closereq to notify IO tasks to return EIO on new
94  * IO requests and wait in process IO count to become 0, indicating there
95  * are no more IO requests. Since ls_cleanup is set, the last lofi_close
96  * will perform unmap and this lofi instance will be removed.
97  * See also lofi_unmap_file() for details.
98  *
99  * Once ls_cleanup is set for the instance, we do not allow lofi_open()
100  * calls to succeed and can have last lofi_close() to remove the instance.
101  *
102  * Known problems:
103  *
104  *	UFS logging. Mounting a UFS filesystem image "logging"
105  *	works for basic copy testing but wedges during a build of ON through
106  *	that image. Some deadlock in lufs holding the log mutex and then
107  *	getting stuck on a buf. So for now, don't do that.
108  *
109  *	Direct I/O. Since the filesystem data is being cached in the buffer
110  *	cache, _and_ again in the underlying filesystem, it's tempting to
111  *	enable direct I/O on the underlying file. Don't, because that deadlocks.
112  *	I think to fix the cache-twice problem we might need filesystem support.
113  *
114  * Interesting things to do:
115  *
116  *	Allow multiple files for each device. A poor-man's metadisk, basically.
117  *
118  *	Pass-through ioctls on block devices. You can (though it's not
119  *	documented), give lofi a block device as a file name. Then we shouldn't
120  *	need to fake a geometry, however, it may be relevant if you're replacing
121  *	metadisk, or using lofi to get crypto.
122  *	It makes sense to do lofiadm -c aes -a /dev/dsk/c0t0d0s4 /dev/lofi/1
123  *	and then in /etc/vfstab have an entry for /dev/lofi/1 as /export/home.
124  *	In fact this even makes sense if you have lofi "above" metadisk.
125  *
126  * Encryption:
127  *	Each lofi device can have its own symmetric key and cipher.
128  *	They are passed to us by lofiadm(1m) in the correct format for use
129  *	with the misc/kcf crypto_* routines.
130  *
131  *	Each block has its own IV, that is calculated in lofi_blk_mech(), based
132  *	on the "master" key held in the lsp and the block number of the buffer.
133  */
134 
135 #include <sys/types.h>
136 #include <netinet/in.h>
137 #include <sys/sysmacros.h>
138 #include <sys/uio.h>
139 #include <sys/kmem.h>
140 #include <sys/cred.h>
141 #include <sys/mman.h>
142 #include <sys/errno.h>
143 #include <sys/aio_req.h>
144 #include <sys/stat.h>
145 #include <sys/file.h>
146 #include <sys/modctl.h>
147 #include <sys/conf.h>
148 #include <sys/debug.h>
149 #include <sys/vnode.h>
150 #include <sys/lofi.h>
151 #include <sys/lofi_impl.h>	/* for cache structure */
152 #include <sys/fcntl.h>
153 #include <sys/pathname.h>
154 #include <sys/filio.h>
155 #include <sys/fdio.h>
156 #include <sys/open.h>
157 #include <sys/disp.h>
158 #include <vm/seg_map.h>
159 #include <sys/ddi.h>
160 #include <sys/sunddi.h>
161 #include <sys/zmod.h>
162 #include <sys/id_space.h>
163 #include <sys/mkdev.h>
164 #include <sys/crypto/common.h>
165 #include <sys/crypto/api.h>
166 #include <sys/rctl.h>
167 #include <sys/vtoc.h>
168 #include <sys/scsi/scsi.h>	/* for DTYPE_DIRECT */
169 #include <sys/scsi/impl/uscsi.h>
170 #include <sys/sysevent/dev.h>
171 #include <LzmaDec.h>
172 
173 #define	NBLOCKS_PROP_NAME	"Nblocks"
174 #define	SIZE_PROP_NAME		"Size"
175 #define	ZONE_PROP_NAME		"zone"
176 
177 #define	SETUP_C_DATA(cd, buf, len)		\
178 	(cd).cd_format = CRYPTO_DATA_RAW;	\
179 	(cd).cd_offset = 0;			\
180 	(cd).cd_miscdata = NULL;		\
181 	(cd).cd_length = (len);			\
182 	(cd).cd_raw.iov_base = (buf);		\
183 	(cd).cd_raw.iov_len = (len);
184 
185 #define	UIO_CHECK(uio)	\
186 	if (((uio)->uio_loffset % DEV_BSIZE) != 0 || \
187 	    ((uio)->uio_resid % DEV_BSIZE) != 0) { \
188 		return (EINVAL); \
189 	}
190 
191 #define	LOFI_TIMEOUT	30
192 
193 static void *lofi_statep;
194 static kmutex_t lofi_lock;		/* state lock */
195 static id_space_t *lofi_id;		/* lofi ID values */
196 static list_t lofi_list;
197 static zone_key_t lofi_zone_key;
198 
199 /*
200  * Because lofi_taskq_nthreads limits the actual swamping of the device, the
201  * maxalloc parameter (lofi_taskq_maxalloc) should be tuned conservatively
202  * high.  If we want to be assured that the underlying device is always busy,
203  * we must be sure that the number of bytes enqueued when the number of
204  * enqueued tasks exceeds maxalloc is sufficient to keep the device busy for
205  * the duration of the sleep time in taskq_ent_alloc().  That is, lofi should
206  * set maxalloc to be the maximum throughput (in bytes per second) of the
207  * underlying device divided by the minimum I/O size.  We assume a realistic
208  * maximum throughput of one hundred megabytes per second; we set maxalloc on
209  * the lofi task queue to be 104857600 divided by DEV_BSIZE.
210  */
211 static int lofi_taskq_maxalloc = 104857600 / DEV_BSIZE;
212 static int lofi_taskq_nthreads = 4;	/* # of taskq threads per device */
213 
214 const char lofi_crypto_magic[6] = LOFI_CRYPTO_MAGIC;
215 
216 /*
217  * To avoid decompressing data in a compressed segment multiple times
218  * when accessing small parts of a segment's data, we cache and reuse
219  * the uncompressed segment's data.
220  *
221  * A single cached segment is sufficient to avoid lots of duplicate
222  * segment decompress operations. A small cache size also reduces the
223  * memory footprint.
224  *
225  * lofi_max_comp_cache is the maximum number of decompressed data segments
226  * cached for each compressed lofi image. It can be set to 0 to disable
227  * caching.
228  */
229 
230 uint32_t lofi_max_comp_cache = 1;
231 
232 static int gzip_decompress(void *src, size_t srclen, void *dst,
233 	size_t *destlen, int level);
234 
235 static int lzma_decompress(void *src, size_t srclen, void *dst,
236 	size_t *dstlen, int level);
237 
238 lofi_compress_info_t lofi_compress_table[LOFI_COMPRESS_FUNCTIONS] = {
239 	{gzip_decompress,	NULL,	6,	"gzip"}, /* default */
240 	{gzip_decompress,	NULL,	6,	"gzip-6"},
241 	{gzip_decompress,	NULL,	9,	"gzip-9"},
242 	{lzma_decompress,	NULL,	0,	"lzma"}
243 };
244 
245 static void lofi_strategy_task(void *);
246 static int lofi_tg_rdwr(dev_info_t *, uchar_t, void *, diskaddr_t,
247     size_t, void *);
248 static int lofi_tg_getinfo(dev_info_t *, int, void *, void *);
249 
250 struct cmlb_tg_ops lofi_tg_ops = {
251 	TG_DK_OPS_VERSION_1,
252 	lofi_tg_rdwr,
253 	lofi_tg_getinfo
254 };
255 
256 /*ARGSUSED*/
257 static void
258 *SzAlloc(void *p, size_t size)
259 {
260 	return (kmem_alloc(size, KM_SLEEP));
261 }
262 
263 /*ARGSUSED*/
264 static void
265 SzFree(void *p, void *address, size_t size)
266 {
267 	kmem_free(address, size);
268 }
269 
270 static ISzAlloc g_Alloc = { SzAlloc, SzFree };
271 
272 /*
273  * Free data referenced by the linked list of cached uncompressed
274  * segments.
275  */
276 static void
277 lofi_free_comp_cache(struct lofi_state *lsp)
278 {
279 	struct lofi_comp_cache *lc;
280 
281 	while ((lc = list_remove_head(&lsp->ls_comp_cache)) != NULL) {
282 		kmem_free(lc->lc_data, lsp->ls_uncomp_seg_sz);
283 		kmem_free(lc, sizeof (struct lofi_comp_cache));
284 		lsp->ls_comp_cache_count--;
285 	}
286 	ASSERT(lsp->ls_comp_cache_count == 0);
287 }
288 
289 static int
290 is_opened(struct lofi_state *lsp)
291 {
292 	int i;
293 	boolean_t last = B_TRUE;
294 
295 	ASSERT(MUTEX_HELD(&lofi_lock));
296 	for (i = 0; i < LOFI_PART_MAX; i++) {
297 		if (lsp->ls_open_lyr[i]) {
298 			last = B_FALSE;
299 			break;
300 		}
301 	}
302 
303 	for (i = 0; last && (i < OTYP_LYR); i++) {
304 		if (lsp->ls_open_reg[i]) {
305 			last = B_FALSE;
306 		}
307 	}
308 
309 	return (!last);
310 }
311 
312 static void
313 lofi_set_cleanup(struct lofi_state *lsp)
314 {
315 	ASSERT(MUTEX_HELD(&lofi_lock));
316 
317 	lsp->ls_cleanup = B_TRUE;
318 
319 	/* wake up any threads waiting on dkiocstate */
320 	cv_broadcast(&lsp->ls_vp_cv);
321 }
322 
323 static void
324 lofi_free_crypto(struct lofi_state *lsp)
325 {
326 	ASSERT(MUTEX_HELD(&lofi_lock));
327 
328 	if (lsp->ls_crypto_enabled) {
329 		/*
330 		 * Clean up the crypto state so that it doesn't hang around
331 		 * in memory after we are done with it.
332 		 */
333 		if (lsp->ls_key.ck_data != NULL) {
334 			bzero(lsp->ls_key.ck_data,
335 			    CRYPTO_BITS2BYTES(lsp->ls_key.ck_length));
336 			kmem_free(lsp->ls_key.ck_data,
337 			    CRYPTO_BITS2BYTES(lsp->ls_key.ck_length));
338 			lsp->ls_key.ck_data = NULL;
339 			lsp->ls_key.ck_length = 0;
340 		}
341 
342 		if (lsp->ls_mech.cm_param != NULL) {
343 			kmem_free(lsp->ls_mech.cm_param,
344 			    lsp->ls_mech.cm_param_len);
345 			lsp->ls_mech.cm_param = NULL;
346 			lsp->ls_mech.cm_param_len = 0;
347 		}
348 
349 		if (lsp->ls_iv_mech.cm_param != NULL) {
350 			kmem_free(lsp->ls_iv_mech.cm_param,
351 			    lsp->ls_iv_mech.cm_param_len);
352 			lsp->ls_iv_mech.cm_param = NULL;
353 			lsp->ls_iv_mech.cm_param_len = 0;
354 		}
355 
356 		mutex_destroy(&lsp->ls_crypto_lock);
357 	}
358 }
359 
360 /* ARGSUSED */
361 static int
362 lofi_tg_rdwr(dev_info_t *dip, uchar_t cmd, void *bufaddr, diskaddr_t start,
363     size_t length, void *tg_cookie)
364 {
365 	struct lofi_state *lsp;
366 	buf_t	*bp;
367 	int	instance;
368 	int	rv = 0;
369 
370 	instance = ddi_get_instance(dip);
371 	if (instance == 0)	/* control node does not have disk */
372 		return (ENXIO);
373 
374 	lsp = ddi_get_soft_state(lofi_statep, instance);
375 
376 	if (lsp == NULL)
377 		return (ENXIO);
378 
379 	if (cmd != TG_READ && cmd != TG_WRITE)
380 		return (EINVAL);
381 
382 	/*
383 	 * Make sure the mapping is set up by checking lsp->ls_vp_ready.
384 	 */
385 	mutex_enter(&lsp->ls_vp_lock);
386 	while (lsp->ls_vp_ready == B_FALSE)
387 		cv_wait(&lsp->ls_vp_cv, &lsp->ls_vp_lock);
388 	mutex_exit(&lsp->ls_vp_lock);
389 
390 	if (P2PHASE(length, (1U << lsp->ls_lbshift)) != 0) {
391 		/* We can only transfer whole blocks at a time! */
392 		return (EINVAL);
393 	}
394 
395 	bp = getrbuf(KM_SLEEP);
396 
397 	if (cmd == TG_READ) {
398 		bp->b_flags = B_READ;
399 	} else {
400 		if (lsp->ls_readonly == B_TRUE) {
401 			freerbuf(bp);
402 			return (EROFS);
403 		}
404 		bp->b_flags = B_WRITE;
405 	}
406 
407 	bp->b_un.b_addr = bufaddr;
408 	bp->b_bcount = length;
409 	bp->b_lblkno = start;
410 	bp->b_private = NULL;
411 	bp->b_edev = lsp->ls_dev;
412 
413 	if (lsp->ls_kstat) {
414 		mutex_enter(lsp->ls_kstat->ks_lock);
415 		kstat_waitq_enter(KSTAT_IO_PTR(lsp->ls_kstat));
416 		mutex_exit(lsp->ls_kstat->ks_lock);
417 	}
418 	(void) taskq_dispatch(lsp->ls_taskq, lofi_strategy_task, bp, KM_SLEEP);
419 	(void) biowait(bp);
420 
421 	rv = geterror(bp);
422 	freerbuf(bp);
423 	return (rv);
424 }
425 
426 /*
427  * Get device geometry info for cmlb.
428  *
429  * We have mapped disk image as virtual block device and have to report
430  * physical/virtual geometry to cmlb.
431  *
432  * So we have two principal cases:
433  * 1. Uninitialised image without any existing labels,
434  *    for this case we fabricate the data based on mapped image.
435  * 2. Image with existing label information.
436  *    Since we have no information how the image was created (it may be
437  *    dump from some physical device), we need to rely on label information
438  *    from image, or we get "corrupted label" errors.
439  *    NOTE: label can be MBR, MBR+SMI, GPT
440  */
441 static int
442 lofi_tg_getinfo(dev_info_t *dip, int cmd, void *arg, void *tg_cookie)
443 {
444 	struct lofi_state *lsp;
445 	int instance;
446 	int ashift;
447 
448 	_NOTE(ARGUNUSED(tg_cookie));
449 	instance = ddi_get_instance(dip);
450 	if (instance == 0)		/* control device has no storage */
451 		return (ENXIO);
452 
453 	lsp = ddi_get_soft_state(lofi_statep, instance);
454 
455 	if (lsp == NULL)
456 		return (ENXIO);
457 
458 	/*
459 	 * Make sure the mapping is set up by checking lsp->ls_vp_ready.
460 	 *
461 	 * When mapping is created, new lofi instance is created and
462 	 * lofi_attach() will call cmlb_attach() as part of the procedure
463 	 * to set the mapping up. This chain of events will happen in
464 	 * the same thread.
465 	 * Since cmlb_attach() will call lofi_tg_getinfo to get
466 	 * capacity, we return error on that call if cookie is set,
467 	 * otherwise lofi_attach will be stuck as the mapping is not yet
468 	 * finalized and lofi is not yet ready.
469 	 * Note, such error is not fatal for cmlb, as the label setup
470 	 * will be finalized when cmlb_validate() is called.
471 	 */
472 	mutex_enter(&lsp->ls_vp_lock);
473 	if (tg_cookie != NULL && lsp->ls_vp_ready == B_FALSE) {
474 		mutex_exit(&lsp->ls_vp_lock);
475 		return (ENXIO);
476 	}
477 	while (lsp->ls_vp_ready == B_FALSE)
478 		cv_wait(&lsp->ls_vp_cv, &lsp->ls_vp_lock);
479 	mutex_exit(&lsp->ls_vp_lock);
480 
481 	ashift = lsp->ls_lbshift;
482 
483 	switch (cmd) {
484 	case TG_GETPHYGEOM: {
485 		cmlb_geom_t *geomp = arg;
486 
487 		geomp->g_capacity	=
488 		    (lsp->ls_vp_size - lsp->ls_crypto_offset) >> ashift;
489 		geomp->g_nsect		= lsp->ls_dkg.dkg_nsect;
490 		geomp->g_nhead		= lsp->ls_dkg.dkg_nhead;
491 		geomp->g_acyl		= lsp->ls_dkg.dkg_acyl;
492 		geomp->g_ncyl		= lsp->ls_dkg.dkg_ncyl;
493 		geomp->g_secsize	= (1U << ashift);
494 		geomp->g_intrlv		= lsp->ls_dkg.dkg_intrlv;
495 		geomp->g_rpm		= lsp->ls_dkg.dkg_rpm;
496 		return (0);
497 	}
498 
499 	case TG_GETCAPACITY:
500 		*(diskaddr_t *)arg =
501 		    (lsp->ls_vp_size - lsp->ls_crypto_offset) >> ashift;
502 		return (0);
503 
504 	case TG_GETBLOCKSIZE:
505 		*(uint32_t *)arg = (1U << ashift);
506 		return (0);
507 
508 	case TG_GETATTR: {
509 		tg_attribute_t *tgattr = arg;
510 
511 		tgattr->media_is_writable = !lsp->ls_readonly;
512 		tgattr->media_is_solid_state = B_FALSE;
513 		tgattr->media_is_rotational = B_FALSE;
514 		return (0);
515 	}
516 
517 	default:
518 		return (EINVAL);
519 	}
520 }
521 
522 static void
523 lofi_destroy(struct lofi_state *lsp, cred_t *credp)
524 {
525 	int id = LOFI_MINOR2ID(getminor(lsp->ls_dev));
526 	int i;
527 
528 	ASSERT(MUTEX_HELD(&lofi_lock));
529 
530 	/*
531 	 * Before we can start to release the other resources,
532 	 * make sure we have all tasks completed and taskq removed.
533 	 */
534 	if (lsp->ls_taskq != NULL) {
535 		taskq_destroy(lsp->ls_taskq);
536 		lsp->ls_taskq = NULL;
537 	}
538 
539 	list_remove(&lofi_list, lsp);
540 
541 	lofi_free_crypto(lsp);
542 
543 	/*
544 	 * Free pre-allocated compressed buffers
545 	 */
546 	if (lsp->ls_comp_bufs != NULL) {
547 		for (i = 0; i < lofi_taskq_nthreads; i++) {
548 			if (lsp->ls_comp_bufs[i].bufsize > 0)
549 				kmem_free(lsp->ls_comp_bufs[i].buf,
550 				    lsp->ls_comp_bufs[i].bufsize);
551 		}
552 		kmem_free(lsp->ls_comp_bufs,
553 		    sizeof (struct compbuf) * lofi_taskq_nthreads);
554 	}
555 
556 	if (lsp->ls_vp != NULL) {
557 		(void) VOP_PUTPAGE(lsp->ls_vp, 0, 0, B_FREE, credp, NULL);
558 		(void) VOP_CLOSE(lsp->ls_vp, lsp->ls_openflag,
559 		    1, 0, credp, NULL);
560 		VN_RELE(lsp->ls_vp);
561 	}
562 	if (lsp->ls_stacked_vp != lsp->ls_vp)
563 		VN_RELE(lsp->ls_stacked_vp);
564 	lsp->ls_vp = lsp->ls_stacked_vp = NULL;
565 
566 	if (lsp->ls_kstat != NULL) {
567 		kstat_delete(lsp->ls_kstat);
568 		lsp->ls_kstat = NULL;
569 	}
570 
571 	/*
572 	 * Free cached decompressed segment data
573 	 */
574 	lofi_free_comp_cache(lsp);
575 	list_destroy(&lsp->ls_comp_cache);
576 
577 	if (lsp->ls_uncomp_seg_sz > 0) {
578 		kmem_free(lsp->ls_comp_index_data, lsp->ls_comp_index_data_sz);
579 		lsp->ls_uncomp_seg_sz = 0;
580 	}
581 
582 	rctl_decr_lofi(lsp->ls_zone.zref_zone, 1);
583 	zone_rele_ref(&lsp->ls_zone, ZONE_REF_LOFI);
584 
585 	mutex_destroy(&lsp->ls_comp_cache_lock);
586 	mutex_destroy(&lsp->ls_comp_bufs_lock);
587 	mutex_destroy(&lsp->ls_kstat_lock);
588 	mutex_destroy(&lsp->ls_vp_lock);
589 	cv_destroy(&lsp->ls_vp_cv);
590 	lsp->ls_vp_ready = B_FALSE;
591 	lsp->ls_vp_closereq = B_FALSE;
592 
593 	ASSERT(ddi_get_soft_state(lofi_statep, id) == lsp);
594 	(void) ndi_devi_offline(lsp->ls_dip, NDI_DEVI_REMOVE);
595 	id_free(lofi_id, id);
596 }
597 
598 static void
599 lofi_free_dev(struct lofi_state *lsp)
600 {
601 	ASSERT(MUTEX_HELD(&lofi_lock));
602 
603 	if (lsp->ls_cmlbhandle != NULL) {
604 		cmlb_invalidate(lsp->ls_cmlbhandle, 0);
605 		cmlb_detach(lsp->ls_cmlbhandle, 0);
606 		cmlb_free_handle(&lsp->ls_cmlbhandle);
607 		lsp->ls_cmlbhandle = NULL;
608 	}
609 	(void) ddi_prop_remove_all(lsp->ls_dip);
610 	ddi_remove_minor_node(lsp->ls_dip, NULL);
611 }
612 
613 /*ARGSUSED*/
614 static void
615 lofi_zone_shutdown(zoneid_t zoneid, void *arg)
616 {
617 	struct lofi_state *lsp;
618 	struct lofi_state *next;
619 
620 	mutex_enter(&lofi_lock);
621 
622 	for (lsp = list_head(&lofi_list); lsp != NULL; lsp = next) {
623 
624 		/* lofi_destroy() frees lsp */
625 		next = list_next(&lofi_list, lsp);
626 
627 		if (lsp->ls_zone.zref_zone->zone_id != zoneid)
628 			continue;
629 
630 		/*
631 		 * No in-zone processes are running, but something has this
632 		 * open.  It's either a global zone process, or a lofi
633 		 * mount.  In either case we set ls_cleanup so the last
634 		 * user destroys the device.
635 		 */
636 		if (is_opened(lsp)) {
637 			lofi_set_cleanup(lsp);
638 		} else {
639 			lofi_free_dev(lsp);
640 			lofi_destroy(lsp, kcred);
641 		}
642 	}
643 
644 	mutex_exit(&lofi_lock);
645 }
646 
647 /*ARGSUSED*/
648 static int
649 lofi_open(dev_t *devp, int flag, int otyp, struct cred *credp)
650 {
651 	int id;
652 	minor_t	part;
653 	uint64_t mask;
654 	diskaddr_t nblks;
655 	diskaddr_t lba;
656 	boolean_t ndelay;
657 
658 	struct lofi_state *lsp;
659 
660 	if (otyp >= OTYPCNT)
661 		return (EINVAL);
662 
663 	ndelay = (flag & (FNDELAY | FNONBLOCK)) ? B_TRUE : B_FALSE;
664 
665 	/*
666 	 * lofiadm -a /dev/lofi/1 gets us here.
667 	 */
668 	if (mutex_owner(&lofi_lock) == curthread)
669 		return (EINVAL);
670 
671 	mutex_enter(&lofi_lock);
672 
673 	id = LOFI_MINOR2ID(getminor(*devp));
674 	part = LOFI_PART(getminor(*devp));
675 	mask = (1U << part);
676 
677 	/* master control device */
678 	if (id == 0) {
679 		mutex_exit(&lofi_lock);
680 		return (0);
681 	}
682 
683 	/* otherwise, the mapping should already exist */
684 	lsp = ddi_get_soft_state(lofi_statep, id);
685 	if (lsp == NULL) {
686 		mutex_exit(&lofi_lock);
687 		return (EINVAL);
688 	}
689 
690 	if (lsp->ls_cleanup == B_TRUE) {
691 		mutex_exit(&lofi_lock);
692 		return (ENXIO);
693 	}
694 
695 	if (lsp->ls_vp == NULL) {
696 		mutex_exit(&lofi_lock);
697 		return (ENXIO);
698 	}
699 
700 	if (lsp->ls_readonly && (flag & FWRITE)) {
701 		mutex_exit(&lofi_lock);
702 		return (EROFS);
703 	}
704 
705 	if ((lsp->ls_open_excl) & (mask)) {
706 		mutex_exit(&lofi_lock);
707 		return (EBUSY);
708 	}
709 
710 	if (flag & FEXCL) {
711 		if (lsp->ls_open_lyr[part]) {
712 			mutex_exit(&lofi_lock);
713 			return (EBUSY);
714 		}
715 		for (int i = 0; i < OTYP_LYR; i++) {
716 			if (lsp->ls_open_reg[i] & mask) {
717 				mutex_exit(&lofi_lock);
718 				return (EBUSY);
719 			}
720 		}
721 	}
722 
723 	if (lsp->ls_cmlbhandle != NULL) {
724 		if (cmlb_validate(lsp->ls_cmlbhandle, 0, 0) != 0) {
725 			/*
726 			 * non-blocking opens are allowed to succeed to
727 			 * support format and fdisk to create partitioning.
728 			 */
729 			if (!ndelay) {
730 				mutex_exit(&lofi_lock);
731 				return (ENXIO);
732 			}
733 		} else if (cmlb_partinfo(lsp->ls_cmlbhandle, part, &nblks, &lba,
734 		    NULL, NULL, 0) == 0) {
735 			if ((!nblks) && ((!ndelay) || (otyp != OTYP_CHR))) {
736 				mutex_exit(&lofi_lock);
737 				return (ENXIO);
738 			}
739 		} else if (!ndelay) {
740 			mutex_exit(&lofi_lock);
741 			return (ENXIO);
742 		}
743 	}
744 
745 	if (otyp == OTYP_LYR) {
746 		lsp->ls_open_lyr[part]++;
747 	} else {
748 		lsp->ls_open_reg[otyp] |= mask;
749 	}
750 	if (flag & FEXCL) {
751 		lsp->ls_open_excl |= mask;
752 	}
753 
754 	mutex_exit(&lofi_lock);
755 	return (0);
756 }
757 
758 /*ARGSUSED*/
759 static int
760 lofi_close(dev_t dev, int flag, int otyp, struct cred *credp)
761 {
762 	minor_t	part;
763 	int id;
764 	uint64_t mask;
765 	struct lofi_state *lsp;
766 
767 	id = LOFI_MINOR2ID(getminor(dev));
768 	part = LOFI_PART(getminor(dev));
769 	mask = (1U << part);
770 
771 	mutex_enter(&lofi_lock);
772 	lsp = ddi_get_soft_state(lofi_statep, id);
773 	if (lsp == NULL) {
774 		mutex_exit(&lofi_lock);
775 		return (EINVAL);
776 	}
777 
778 	if (id == 0) {
779 		mutex_exit(&lofi_lock);
780 		return (0);
781 	}
782 
783 	if (lsp->ls_open_excl & mask)
784 		lsp->ls_open_excl &= ~mask;
785 
786 	if (otyp == OTYP_LYR) {
787 		lsp->ls_open_lyr[part]--;
788 	} else {
789 		lsp->ls_open_reg[otyp] &= ~mask;
790 	}
791 
792 	/*
793 	 * If we forcibly closed the underlying device (li_force), or
794 	 * asked for cleanup (li_cleanup), finish up if we're the last
795 	 * out of the door.
796 	 */
797 	if (!is_opened(lsp) &&
798 	    (lsp->ls_cleanup == B_TRUE || lsp->ls_vp == NULL)) {
799 		lofi_free_dev(lsp);
800 		lofi_destroy(lsp, credp);
801 	}
802 
803 	mutex_exit(&lofi_lock);
804 	return (0);
805 }
806 
807 /*
808  * Sets the mechanism's initialization vector (IV) if one is needed.
809  * The IV is computed from the data block number.  lsp->ls_mech is
810  * altered so that:
811  *	lsp->ls_mech.cm_param_len is set to the IV len.
812  *	lsp->ls_mech.cm_param is set to the IV.
813  */
814 static int
815 lofi_blk_mech(struct lofi_state *lsp, longlong_t lblkno)
816 {
817 	int	ret;
818 	crypto_data_t cdata;
819 	char	*iv;
820 	size_t	iv_len;
821 	size_t	min;
822 	void	*data;
823 	size_t	datasz;
824 
825 	ASSERT(MUTEX_HELD(&lsp->ls_crypto_lock));
826 
827 	if (lsp == NULL)
828 		return (CRYPTO_DEVICE_ERROR);
829 
830 	/* lsp->ls_mech.cm_param{_len} has already been set for static iv */
831 	if (lsp->ls_iv_type == IVM_NONE) {
832 		return (CRYPTO_SUCCESS);
833 	}
834 
835 	/*
836 	 * if kmem already alloced from previous call and it's the same size
837 	 * we need now, just recycle it; allocate new kmem only if we have to
838 	 */
839 	if (lsp->ls_mech.cm_param == NULL ||
840 	    lsp->ls_mech.cm_param_len != lsp->ls_iv_len) {
841 		iv_len = lsp->ls_iv_len;
842 		iv = kmem_zalloc(iv_len, KM_SLEEP);
843 	} else {
844 		iv_len = lsp->ls_mech.cm_param_len;
845 		iv = lsp->ls_mech.cm_param;
846 		bzero(iv, iv_len);
847 	}
848 
849 	switch (lsp->ls_iv_type) {
850 	case IVM_ENC_BLKNO:
851 		/* iv is not static, lblkno changes each time */
852 		data = &lblkno;
853 		datasz = sizeof (lblkno);
854 		break;
855 	default:
856 		data = 0;
857 		datasz = 0;
858 		break;
859 	}
860 
861 	/*
862 	 * write blkno into the iv buffer padded on the left in case
863 	 * blkno ever grows bigger than its current longlong_t size
864 	 * or a variation other than blkno is used for the iv data
865 	 */
866 	min = MIN(datasz, iv_len);
867 	bcopy(data, iv + (iv_len - min), min);
868 
869 	/* encrypt the data in-place to get the IV */
870 	SETUP_C_DATA(cdata, iv, iv_len);
871 
872 	ret = crypto_encrypt(&lsp->ls_iv_mech, &cdata, &lsp->ls_key,
873 	    NULL, NULL, NULL);
874 	if (ret != CRYPTO_SUCCESS) {
875 		cmn_err(CE_WARN, "failed to create iv for block %lld: (0x%x)",
876 		    lblkno, ret);
877 		if (lsp->ls_mech.cm_param != iv)
878 			kmem_free(iv, iv_len);
879 
880 		return (ret);
881 	}
882 
883 	/* clean up the iv from the last computation */
884 	if (lsp->ls_mech.cm_param != NULL && lsp->ls_mech.cm_param != iv)
885 		kmem_free(lsp->ls_mech.cm_param, lsp->ls_mech.cm_param_len);
886 
887 	lsp->ls_mech.cm_param_len = iv_len;
888 	lsp->ls_mech.cm_param = iv;
889 
890 	return (CRYPTO_SUCCESS);
891 }
892 
893 /*
894  * Performs encryption and decryption of a chunk of data of size "len",
895  * one DEV_BSIZE block at a time.  "len" is assumed to be a multiple of
896  * DEV_BSIZE.
897  */
898 static int
899 lofi_crypto(struct lofi_state *lsp, struct buf *bp, caddr_t plaintext,
900     caddr_t ciphertext, size_t len, boolean_t op_encrypt)
901 {
902 	crypto_data_t cdata;
903 	crypto_data_t wdata;
904 	int ret;
905 	longlong_t lblkno = bp->b_lblkno;
906 
907 	mutex_enter(&lsp->ls_crypto_lock);
908 
909 	/*
910 	 * though we could encrypt/decrypt entire "len" chunk of data, we need
911 	 * to break it into DEV_BSIZE pieces to capture blkno incrementing
912 	 */
913 	SETUP_C_DATA(cdata, plaintext, len);
914 	cdata.cd_length = DEV_BSIZE;
915 	if (ciphertext != NULL) {		/* not in-place crypto */
916 		SETUP_C_DATA(wdata, ciphertext, len);
917 		wdata.cd_length = DEV_BSIZE;
918 	}
919 
920 	do {
921 		ret = lofi_blk_mech(lsp, lblkno);
922 		if (ret != CRYPTO_SUCCESS)
923 			continue;
924 
925 		if (op_encrypt) {
926 			ret = crypto_encrypt(&lsp->ls_mech, &cdata,
927 			    &lsp->ls_key, NULL,
928 			    ((ciphertext != NULL) ? &wdata : NULL), NULL);
929 		} else {
930 			ret = crypto_decrypt(&lsp->ls_mech, &cdata,
931 			    &lsp->ls_key, NULL,
932 			    ((ciphertext != NULL) ? &wdata : NULL), NULL);
933 		}
934 
935 		cdata.cd_offset += DEV_BSIZE;
936 		if (ciphertext != NULL)
937 			wdata.cd_offset += DEV_BSIZE;
938 		lblkno++;
939 	} while (ret == CRYPTO_SUCCESS && cdata.cd_offset < len);
940 
941 	mutex_exit(&lsp->ls_crypto_lock);
942 
943 	if (ret != CRYPTO_SUCCESS) {
944 		cmn_err(CE_WARN, "%s failed for block %lld:  (0x%x)",
945 		    op_encrypt ? "crypto_encrypt()" : "crypto_decrypt()",
946 		    lblkno, ret);
947 	}
948 
949 	return (ret);
950 }
951 
952 #define	RDWR_RAW	1
953 #define	RDWR_BCOPY	2
954 
955 static int
956 lofi_rdwr(caddr_t bufaddr, offset_t offset, struct buf *bp,
957     struct lofi_state *lsp, size_t len, int method, caddr_t bcopy_locn)
958 {
959 	ssize_t resid;
960 	int isread;
961 	int error;
962 
963 	/*
964 	 * Handles reads/writes for both plain and encrypted lofi
965 	 * Note:  offset is already shifted by lsp->ls_crypto_offset
966 	 * when it gets here.
967 	 */
968 
969 	isread = bp->b_flags & B_READ;
970 	if (isread) {
971 		if (method == RDWR_BCOPY) {
972 			/* DO NOT update bp->b_resid for bcopy */
973 			bcopy(bcopy_locn, bufaddr, len);
974 			error = 0;
975 		} else {		/* RDWR_RAW */
976 			error = vn_rdwr(UIO_READ, lsp->ls_vp, bufaddr, len,
977 			    offset, UIO_SYSSPACE, 0, RLIM64_INFINITY, kcred,
978 			    &resid);
979 			bp->b_resid = resid;
980 		}
981 		if (lsp->ls_crypto_enabled && error == 0) {
982 			if (lofi_crypto(lsp, bp, bufaddr, NULL, len,
983 			    B_FALSE) != CRYPTO_SUCCESS) {
984 				/*
985 				 * XXX: original code didn't set residual
986 				 * back to len because no error was expected
987 				 * from bcopy() if encryption is not enabled
988 				 */
989 				if (method != RDWR_BCOPY)
990 					bp->b_resid = len;
991 				error = EIO;
992 			}
993 		}
994 		return (error);
995 	} else {
996 		void *iobuf = bufaddr;
997 
998 		if (lsp->ls_crypto_enabled) {
999 			/* don't do in-place crypto to keep bufaddr intact */
1000 			iobuf = kmem_alloc(len, KM_SLEEP);
1001 			if (lofi_crypto(lsp, bp, bufaddr, iobuf, len,
1002 			    B_TRUE) != CRYPTO_SUCCESS) {
1003 				kmem_free(iobuf, len);
1004 				if (method != RDWR_BCOPY)
1005 					bp->b_resid = len;
1006 				return (EIO);
1007 			}
1008 		}
1009 		if (method == RDWR_BCOPY) {
1010 			/* DO NOT update bp->b_resid for bcopy */
1011 			bcopy(iobuf, bcopy_locn, len);
1012 			error = 0;
1013 		} else {		/* RDWR_RAW */
1014 			error = vn_rdwr(UIO_WRITE, lsp->ls_vp, iobuf, len,
1015 			    offset, UIO_SYSSPACE, 0, RLIM64_INFINITY, kcred,
1016 			    &resid);
1017 			bp->b_resid = resid;
1018 		}
1019 		if (lsp->ls_crypto_enabled) {
1020 			kmem_free(iobuf, len);
1021 		}
1022 		return (error);
1023 	}
1024 }
1025 
1026 static int
1027 lofi_mapped_rdwr(caddr_t bufaddr, offset_t offset, struct buf *bp,
1028     struct lofi_state *lsp)
1029 {
1030 	int error;
1031 	offset_t alignedoffset, mapoffset;
1032 	size_t	xfersize;
1033 	int	isread;
1034 	int	smflags;
1035 	caddr_t	mapaddr;
1036 	size_t	len;
1037 	enum seg_rw srw;
1038 	int	save_error;
1039 
1040 	/*
1041 	 * Note:  offset is already shifted by lsp->ls_crypto_offset
1042 	 * when it gets here.
1043 	 */
1044 	if (lsp->ls_crypto_enabled)
1045 		ASSERT(lsp->ls_vp_comp_size == lsp->ls_vp_size);
1046 
1047 	/*
1048 	 * segmap always gives us an 8K (MAXBSIZE) chunk, aligned on
1049 	 * an 8K boundary, but the buf transfer address may not be
1050 	 * aligned on more than a 512-byte boundary (we don't enforce
1051 	 * that even though we could). This matters since the initial
1052 	 * part of the transfer may not start at offset 0 within the
1053 	 * segmap'd chunk. So we have to compensate for that with
1054 	 * 'mapoffset'. Subsequent chunks always start off at the
1055 	 * beginning, and the last is capped by b_resid
1056 	 *
1057 	 * Visually, where "|" represents page map boundaries:
1058 	 *   alignedoffset (mapaddr begins at this segmap boundary)
1059 	 *    |   offset (from beginning of file)
1060 	 *    |    |	   len
1061 	 *    v    v	    v
1062 	 * ===|====X========|====...======|========X====|====
1063 	 *	   /-------------...---------------/
1064 	 *		^ bp->b_bcount/bp->b_resid at start
1065 	 *    /----/--------/----...------/--------/
1066 	 *	^	^	^   ^		^
1067 	 *	|	|	|   |		nth xfersize (<= MAXBSIZE)
1068 	 *	|	|	2nd thru n-1st xfersize (= MAXBSIZE)
1069 	 *	|	1st xfersize (<= MAXBSIZE)
1070 	 *    mapoffset (offset into 1st segmap, non-0 1st time, 0 thereafter)
1071 	 *
1072 	 * Notes: "alignedoffset" is "offset" rounded down to nearest
1073 	 * MAXBSIZE boundary.  "len" is next page boundary of size
1074 	 * PAGESIZE after "alignedoffset".
1075 	 */
1076 	mapoffset = offset & MAXBOFFSET;
1077 	alignedoffset = offset - mapoffset;
1078 	bp->b_resid = bp->b_bcount;
1079 	isread = bp->b_flags & B_READ;
1080 	srw = isread ? S_READ : S_WRITE;
1081 	do {
1082 		xfersize = MIN(lsp->ls_vp_comp_size - offset,
1083 		    MIN(MAXBSIZE - mapoffset, bp->b_resid));
1084 		len = roundup(mapoffset + xfersize, PAGESIZE);
1085 		mapaddr = segmap_getmapflt(segkmap, lsp->ls_vp,
1086 		    alignedoffset, MAXBSIZE, 1, srw);
1087 		/*
1088 		 * Now fault in the pages. This lets us check
1089 		 * for errors before we reference mapaddr and
1090 		 * try to resolve the fault in bcopy (which would
1091 		 * panic instead). And this can easily happen,
1092 		 * particularly if you've lofi'd a file over NFS
1093 		 * and someone deletes the file on the server.
1094 		 */
1095 		error = segmap_fault(kas.a_hat, segkmap, mapaddr,
1096 		    len, F_SOFTLOCK, srw);
1097 		if (error) {
1098 			(void) segmap_release(segkmap, mapaddr, 0);
1099 			if (FC_CODE(error) == FC_OBJERR)
1100 				error = FC_ERRNO(error);
1101 			else
1102 				error = EIO;
1103 			break;
1104 		}
1105 		/* error may be non-zero for encrypted lofi */
1106 		error = lofi_rdwr(bufaddr, 0, bp, lsp, xfersize,
1107 		    RDWR_BCOPY, mapaddr + mapoffset);
1108 		if (error == 0) {
1109 			bp->b_resid -= xfersize;
1110 			bufaddr += xfersize;
1111 			offset += xfersize;
1112 		}
1113 		smflags = 0;
1114 		if (isread) {
1115 			smflags |= SM_FREE;
1116 			/*
1117 			 * If we're reading an entire page starting
1118 			 * at a page boundary, there's a good chance
1119 			 * we won't need it again. Put it on the
1120 			 * head of the freelist.
1121 			 */
1122 			if (mapoffset == 0 && xfersize == MAXBSIZE)
1123 				smflags |= SM_DONTNEED;
1124 		} else {
1125 			/*
1126 			 * Write back good pages, it is okay to
1127 			 * always release asynchronous here as we'll
1128 			 * follow with VOP_FSYNC for B_SYNC buffers.
1129 			 */
1130 			if (error == 0)
1131 				smflags |= SM_WRITE | SM_ASYNC;
1132 		}
1133 		(void) segmap_fault(kas.a_hat, segkmap, mapaddr,
1134 		    len, F_SOFTUNLOCK, srw);
1135 		save_error = segmap_release(segkmap, mapaddr, smflags);
1136 		if (error == 0)
1137 			error = save_error;
1138 		/* only the first map may start partial */
1139 		mapoffset = 0;
1140 		alignedoffset += MAXBSIZE;
1141 	} while ((error == 0) && (bp->b_resid > 0) &&
1142 	    (offset < lsp->ls_vp_comp_size));
1143 
1144 	return (error);
1145 }
1146 
1147 /*
1148  * Check if segment seg_index is present in the decompressed segment
1149  * data cache.
1150  *
1151  * Returns a pointer to the decompressed segment data cache entry if
1152  * found, and NULL when decompressed data for this segment is not yet
1153  * cached.
1154  */
1155 static struct lofi_comp_cache *
1156 lofi_find_comp_data(struct lofi_state *lsp, uint64_t seg_index)
1157 {
1158 	struct lofi_comp_cache *lc;
1159 
1160 	ASSERT(MUTEX_HELD(&lsp->ls_comp_cache_lock));
1161 
1162 	for (lc = list_head(&lsp->ls_comp_cache); lc != NULL;
1163 	    lc = list_next(&lsp->ls_comp_cache, lc)) {
1164 		if (lc->lc_index == seg_index) {
1165 			/*
1166 			 * Decompressed segment data was found in the
1167 			 * cache.
1168 			 *
1169 			 * The cache uses an LRU replacement strategy;
1170 			 * move the entry to head of list.
1171 			 */
1172 			list_remove(&lsp->ls_comp_cache, lc);
1173 			list_insert_head(&lsp->ls_comp_cache, lc);
1174 			return (lc);
1175 		}
1176 	}
1177 	return (NULL);
1178 }
1179 
1180 /*
1181  * Add the data for a decompressed segment at segment index
1182  * seg_index to the cache of the decompressed segments.
1183  *
1184  * Returns a pointer to the cache element structure in case
1185  * the data was added to the cache; returns NULL when the data
1186  * wasn't cached.
1187  */
1188 static struct lofi_comp_cache *
1189 lofi_add_comp_data(struct lofi_state *lsp, uint64_t seg_index,
1190     uchar_t *data)
1191 {
1192 	struct lofi_comp_cache *lc;
1193 
1194 	ASSERT(MUTEX_HELD(&lsp->ls_comp_cache_lock));
1195 
1196 	while (lsp->ls_comp_cache_count > lofi_max_comp_cache) {
1197 		lc = list_remove_tail(&lsp->ls_comp_cache);
1198 		ASSERT(lc != NULL);
1199 		kmem_free(lc->lc_data, lsp->ls_uncomp_seg_sz);
1200 		kmem_free(lc, sizeof (struct lofi_comp_cache));
1201 		lsp->ls_comp_cache_count--;
1202 	}
1203 
1204 	/*
1205 	 * Do not cache when disabled by tunable variable
1206 	 */
1207 	if (lofi_max_comp_cache == 0)
1208 		return (NULL);
1209 
1210 	/*
1211 	 * When the cache has not yet reached the maximum allowed
1212 	 * number of segments, allocate a new cache element.
1213 	 * Otherwise the cache is full; reuse the last list element
1214 	 * (LRU) for caching the decompressed segment data.
1215 	 *
1216 	 * The cache element for the new decompressed segment data is
1217 	 * added to the head of the list.
1218 	 */
1219 	if (lsp->ls_comp_cache_count < lofi_max_comp_cache) {
1220 		lc = kmem_alloc(sizeof (struct lofi_comp_cache), KM_SLEEP);
1221 		lc->lc_data = NULL;
1222 		list_insert_head(&lsp->ls_comp_cache, lc);
1223 		lsp->ls_comp_cache_count++;
1224 	} else {
1225 		lc = list_remove_tail(&lsp->ls_comp_cache);
1226 		if (lc == NULL)
1227 			return (NULL);
1228 		list_insert_head(&lsp->ls_comp_cache, lc);
1229 	}
1230 
1231 	/*
1232 	 * Free old uncompressed segment data when reusing a cache
1233 	 * entry.
1234 	 */
1235 	if (lc->lc_data != NULL)
1236 		kmem_free(lc->lc_data, lsp->ls_uncomp_seg_sz);
1237 
1238 	lc->lc_data = data;
1239 	lc->lc_index = seg_index;
1240 	return (lc);
1241 }
1242 
1243 
1244 /*ARGSUSED*/
1245 static int
1246 gzip_decompress(void *src, size_t srclen, void *dst,
1247     size_t *dstlen, int level)
1248 {
1249 	ASSERT(*dstlen >= srclen);
1250 
1251 	if (z_uncompress(dst, dstlen, src, srclen) != Z_OK)
1252 		return (-1);
1253 	return (0);
1254 }
1255 
1256 #define	LZMA_HEADER_SIZE	(LZMA_PROPS_SIZE + 8)
1257 /*ARGSUSED*/
1258 static int
1259 lzma_decompress(void *src, size_t srclen, void *dst,
1260     size_t *dstlen, int level)
1261 {
1262 	size_t insizepure;
1263 	void *actual_src;
1264 	ELzmaStatus status;
1265 
1266 	insizepure = srclen - LZMA_HEADER_SIZE;
1267 	actual_src = (void *)((Byte *)src + LZMA_HEADER_SIZE);
1268 
1269 	if (LzmaDecode((Byte *)dst, (size_t *)dstlen,
1270 	    (const Byte *)actual_src, &insizepure,
1271 	    (const Byte *)src, LZMA_PROPS_SIZE, LZMA_FINISH_ANY, &status,
1272 	    &g_Alloc) != SZ_OK) {
1273 		return (-1);
1274 	}
1275 	return (0);
1276 }
1277 
1278 /*
1279  * This is basically what strategy used to be before we found we
1280  * needed task queues.
1281  */
1282 static void
1283 lofi_strategy_task(void *arg)
1284 {
1285 	struct buf *bp = (struct buf *)arg;
1286 	int error;
1287 	int syncflag = 0;
1288 	struct lofi_state *lsp;
1289 	offset_t offset;
1290 	caddr_t	bufaddr;
1291 	size_t	len;
1292 	size_t	xfersize;
1293 	boolean_t bufinited = B_FALSE;
1294 
1295 	lsp = ddi_get_soft_state(lofi_statep,
1296 	    LOFI_MINOR2ID(getminor(bp->b_edev)));
1297 
1298 	if (lsp == NULL) {
1299 		error = ENXIO;
1300 		goto errout;
1301 	}
1302 	if (lsp->ls_kstat) {
1303 		mutex_enter(lsp->ls_kstat->ks_lock);
1304 		kstat_waitq_to_runq(KSTAT_IO_PTR(lsp->ls_kstat));
1305 		mutex_exit(lsp->ls_kstat->ks_lock);
1306 	}
1307 
1308 	mutex_enter(&lsp->ls_vp_lock);
1309 	lsp->ls_vp_iocount++;
1310 	mutex_exit(&lsp->ls_vp_lock);
1311 
1312 	bp_mapin(bp);
1313 	bufaddr = bp->b_un.b_addr;
1314 	offset = (bp->b_lblkno + (diskaddr_t)(uintptr_t)bp->b_private)
1315 	    << lsp->ls_lbshift;	/* offset within file */
1316 	if (lsp->ls_crypto_enabled) {
1317 		/* encrypted data really begins after crypto header */
1318 		offset += lsp->ls_crypto_offset;
1319 	}
1320 	len = bp->b_bcount;
1321 	bufinited = B_TRUE;
1322 
1323 	if (lsp->ls_vp == NULL || lsp->ls_vp_closereq) {
1324 		error = EIO;
1325 		goto errout;
1326 	}
1327 
1328 	/*
1329 	 * If we're writing and the buffer was not B_ASYNC
1330 	 * we'll follow up with a VOP_FSYNC() to force any
1331 	 * asynchronous I/O to stable storage.
1332 	 */
1333 	if (!(bp->b_flags & B_READ) && !(bp->b_flags & B_ASYNC))
1334 		syncflag = FSYNC;
1335 
1336 	/*
1337 	 * We used to always use vn_rdwr here, but we cannot do that because
1338 	 * we might decide to read or write from the the underlying
1339 	 * file during this call, which would be a deadlock because
1340 	 * we have the rw_lock. So instead we page, unless it's not
1341 	 * mapable or it's a character device or it's an encrypted lofi.
1342 	 */
1343 	if ((lsp->ls_vp->v_flag & VNOMAP) || (lsp->ls_vp->v_type == VCHR) ||
1344 	    lsp->ls_crypto_enabled) {
1345 		error = lofi_rdwr(bufaddr, offset, bp, lsp, len, RDWR_RAW,
1346 		    NULL);
1347 	} else if (lsp->ls_uncomp_seg_sz == 0) {
1348 		error = lofi_mapped_rdwr(bufaddr, offset, bp, lsp);
1349 	} else {
1350 		uchar_t *compressed_seg = NULL, *cmpbuf;
1351 		uchar_t *uncompressed_seg = NULL;
1352 		lofi_compress_info_t *li;
1353 		size_t oblkcount;
1354 		ulong_t seglen;
1355 		uint64_t sblkno, eblkno, cmpbytes;
1356 		uint64_t uncompressed_seg_index;
1357 		struct lofi_comp_cache *lc;
1358 		offset_t sblkoff, eblkoff;
1359 		u_offset_t salign, ealign;
1360 		u_offset_t sdiff;
1361 		uint32_t comp_data_sz;
1362 		uint64_t i;
1363 		int j;
1364 
1365 		/*
1366 		 * From here on we're dealing primarily with compressed files
1367 		 */
1368 		ASSERT(!lsp->ls_crypto_enabled);
1369 
1370 		/*
1371 		 * Compressed files can only be read from and
1372 		 * not written to
1373 		 */
1374 		if (!(bp->b_flags & B_READ)) {
1375 			bp->b_resid = bp->b_bcount;
1376 			error = EROFS;
1377 			goto done;
1378 		}
1379 
1380 		ASSERT(lsp->ls_comp_algorithm_index >= 0);
1381 		li = &lofi_compress_table[lsp->ls_comp_algorithm_index];
1382 		/*
1383 		 * Compute starting and ending compressed segment numbers
1384 		 * We use only bitwise operations avoiding division and
1385 		 * modulus because we enforce the compression segment size
1386 		 * to a power of 2
1387 		 */
1388 		sblkno = offset >> lsp->ls_comp_seg_shift;
1389 		sblkoff = offset & (lsp->ls_uncomp_seg_sz - 1);
1390 		eblkno = (offset + bp->b_bcount) >> lsp->ls_comp_seg_shift;
1391 		eblkoff = (offset + bp->b_bcount) & (lsp->ls_uncomp_seg_sz - 1);
1392 
1393 		/*
1394 		 * Check the decompressed segment cache.
1395 		 *
1396 		 * The cache is used only when the requested data
1397 		 * is within a segment. Requests that cross
1398 		 * segment boundaries bypass the cache.
1399 		 */
1400 		if (sblkno == eblkno ||
1401 		    (sblkno + 1 == eblkno && eblkoff == 0)) {
1402 			/*
1403 			 * Request doesn't cross a segment boundary,
1404 			 * now check the cache.
1405 			 */
1406 			mutex_enter(&lsp->ls_comp_cache_lock);
1407 			lc = lofi_find_comp_data(lsp, sblkno);
1408 			if (lc != NULL) {
1409 				/*
1410 				 * We've found the decompressed segment
1411 				 * data in the cache; reuse it.
1412 				 */
1413 				bcopy(lc->lc_data + sblkoff, bufaddr,
1414 				    bp->b_bcount);
1415 				mutex_exit(&lsp->ls_comp_cache_lock);
1416 				bp->b_resid = 0;
1417 				error = 0;
1418 				goto done;
1419 			}
1420 			mutex_exit(&lsp->ls_comp_cache_lock);
1421 		}
1422 
1423 		/*
1424 		 * Align start offset to block boundary for segmap
1425 		 */
1426 		salign = lsp->ls_comp_seg_index[sblkno];
1427 		sdiff = salign & (DEV_BSIZE - 1);
1428 		salign -= sdiff;
1429 		if (eblkno >= (lsp->ls_comp_index_sz - 1)) {
1430 			/*
1431 			 * We're dealing with the last segment of
1432 			 * the compressed file -- the size of this
1433 			 * segment *may not* be the same as the
1434 			 * segment size for the file
1435 			 */
1436 			eblkoff = (offset + bp->b_bcount) &
1437 			    (lsp->ls_uncomp_last_seg_sz - 1);
1438 			ealign = lsp->ls_vp_comp_size;
1439 		} else {
1440 			ealign = lsp->ls_comp_seg_index[eblkno + 1];
1441 		}
1442 
1443 		/*
1444 		 * Preserve original request paramaters
1445 		 */
1446 		oblkcount = bp->b_bcount;
1447 
1448 		/*
1449 		 * Assign the calculated parameters
1450 		 */
1451 		comp_data_sz = ealign - salign;
1452 		bp->b_bcount = comp_data_sz;
1453 
1454 		/*
1455 		 * Buffers to hold compressed segments are pre-allocated
1456 		 * on a per-thread basis. Find a pre-allocated buffer
1457 		 * that is not currently in use and mark it for use.
1458 		 */
1459 		mutex_enter(&lsp->ls_comp_bufs_lock);
1460 		for (j = 0; j < lofi_taskq_nthreads; j++) {
1461 			if (lsp->ls_comp_bufs[j].inuse == 0) {
1462 				lsp->ls_comp_bufs[j].inuse = 1;
1463 				break;
1464 			}
1465 		}
1466 
1467 		mutex_exit(&lsp->ls_comp_bufs_lock);
1468 		ASSERT(j < lofi_taskq_nthreads);
1469 
1470 		/*
1471 		 * If the pre-allocated buffer size does not match
1472 		 * the size of the I/O request, re-allocate it with
1473 		 * the appropriate size
1474 		 */
1475 		if (lsp->ls_comp_bufs[j].bufsize < bp->b_bcount) {
1476 			if (lsp->ls_comp_bufs[j].bufsize > 0)
1477 				kmem_free(lsp->ls_comp_bufs[j].buf,
1478 				    lsp->ls_comp_bufs[j].bufsize);
1479 			lsp->ls_comp_bufs[j].buf = kmem_alloc(bp->b_bcount,
1480 			    KM_SLEEP);
1481 			lsp->ls_comp_bufs[j].bufsize = bp->b_bcount;
1482 		}
1483 		compressed_seg = lsp->ls_comp_bufs[j].buf;
1484 
1485 		/*
1486 		 * Map in the calculated number of blocks
1487 		 */
1488 		error = lofi_mapped_rdwr((caddr_t)compressed_seg, salign,
1489 		    bp, lsp);
1490 
1491 		bp->b_bcount = oblkcount;
1492 		bp->b_resid = oblkcount;
1493 		if (error != 0)
1494 			goto done;
1495 
1496 		/*
1497 		 * decompress compressed blocks start
1498 		 */
1499 		cmpbuf = compressed_seg + sdiff;
1500 		for (i = sblkno; i <= eblkno; i++) {
1501 			ASSERT(i < lsp->ls_comp_index_sz - 1);
1502 			uchar_t *useg;
1503 
1504 			/*
1505 			 * The last segment is special in that it is
1506 			 * most likely not going to be the same
1507 			 * (uncompressed) size as the other segments.
1508 			 */
1509 			if (i == (lsp->ls_comp_index_sz - 2)) {
1510 				seglen = lsp->ls_uncomp_last_seg_sz;
1511 			} else {
1512 				seglen = lsp->ls_uncomp_seg_sz;
1513 			}
1514 
1515 			/*
1516 			 * Each of the segment index entries contains
1517 			 * the starting block number for that segment.
1518 			 * The number of compressed bytes in a segment
1519 			 * is thus the difference between the starting
1520 			 * block number of this segment and the starting
1521 			 * block number of the next segment.
1522 			 */
1523 			cmpbytes = lsp->ls_comp_seg_index[i + 1] -
1524 			    lsp->ls_comp_seg_index[i];
1525 
1526 			/*
1527 			 * The first byte in a compressed segment is a flag
1528 			 * that indicates whether this segment is compressed
1529 			 * at all.
1530 			 *
1531 			 * The variable 'useg' is used (instead of
1532 			 * uncompressed_seg) in this loop to keep a
1533 			 * reference to the uncompressed segment.
1534 			 *
1535 			 * N.B. If 'useg' is replaced with uncompressed_seg,
1536 			 * it leads to memory leaks and heap corruption in
1537 			 * corner cases where compressed segments lie
1538 			 * adjacent to uncompressed segments.
1539 			 */
1540 			if (*cmpbuf == UNCOMPRESSED) {
1541 				useg = cmpbuf + SEGHDR;
1542 			} else {
1543 				if (uncompressed_seg == NULL)
1544 					uncompressed_seg =
1545 					    kmem_alloc(lsp->ls_uncomp_seg_sz,
1546 					    KM_SLEEP);
1547 				useg = uncompressed_seg;
1548 				uncompressed_seg_index = i;
1549 
1550 				if (li->l_decompress((cmpbuf + SEGHDR),
1551 				    (cmpbytes - SEGHDR), uncompressed_seg,
1552 				    &seglen, li->l_level) != 0) {
1553 					error = EIO;
1554 					goto done;
1555 				}
1556 			}
1557 
1558 			/*
1559 			 * Determine how much uncompressed data we
1560 			 * have to copy and copy it
1561 			 */
1562 			xfersize = lsp->ls_uncomp_seg_sz - sblkoff;
1563 			if (i == eblkno)
1564 				xfersize -= (lsp->ls_uncomp_seg_sz - eblkoff);
1565 
1566 			bcopy((useg + sblkoff), bufaddr, xfersize);
1567 
1568 			cmpbuf += cmpbytes;
1569 			bufaddr += xfersize;
1570 			bp->b_resid -= xfersize;
1571 			sblkoff = 0;
1572 
1573 			if (bp->b_resid == 0)
1574 				break;
1575 		} /* decompress compressed blocks ends */
1576 
1577 		/*
1578 		 * Skip to done if there is no uncompressed data to cache
1579 		 */
1580 		if (uncompressed_seg == NULL)
1581 			goto done;
1582 
1583 		/*
1584 		 * Add the data for the last decompressed segment to
1585 		 * the cache.
1586 		 *
1587 		 * In case the uncompressed segment data was added to (and
1588 		 * is referenced by) the cache, make sure we don't free it
1589 		 * here.
1590 		 */
1591 		mutex_enter(&lsp->ls_comp_cache_lock);
1592 		if ((lc = lofi_add_comp_data(lsp, uncompressed_seg_index,
1593 		    uncompressed_seg)) != NULL) {
1594 			uncompressed_seg = NULL;
1595 		}
1596 		mutex_exit(&lsp->ls_comp_cache_lock);
1597 
1598 done:
1599 		if (compressed_seg != NULL) {
1600 			mutex_enter(&lsp->ls_comp_bufs_lock);
1601 			lsp->ls_comp_bufs[j].inuse = 0;
1602 			mutex_exit(&lsp->ls_comp_bufs_lock);
1603 		}
1604 		if (uncompressed_seg != NULL)
1605 			kmem_free(uncompressed_seg, lsp->ls_uncomp_seg_sz);
1606 	} /* end of handling compressed files */
1607 
1608 	if ((error == 0) && (syncflag != 0))
1609 		error = VOP_FSYNC(lsp->ls_vp, syncflag, kcred, NULL);
1610 
1611 errout:
1612 	if (bufinited && lsp->ls_kstat) {
1613 		size_t n_done = bp->b_bcount - bp->b_resid;
1614 		kstat_io_t *kioptr;
1615 
1616 		mutex_enter(lsp->ls_kstat->ks_lock);
1617 		kioptr = KSTAT_IO_PTR(lsp->ls_kstat);
1618 		if (bp->b_flags & B_READ) {
1619 			kioptr->nread += n_done;
1620 			kioptr->reads++;
1621 		} else {
1622 			kioptr->nwritten += n_done;
1623 			kioptr->writes++;
1624 		}
1625 		kstat_runq_exit(kioptr);
1626 		mutex_exit(lsp->ls_kstat->ks_lock);
1627 	}
1628 
1629 	mutex_enter(&lsp->ls_vp_lock);
1630 	if (--lsp->ls_vp_iocount == 0)
1631 		cv_broadcast(&lsp->ls_vp_cv);
1632 	mutex_exit(&lsp->ls_vp_lock);
1633 
1634 	bioerror(bp, error);
1635 	biodone(bp);
1636 }
1637 
1638 static int
1639 lofi_strategy(struct buf *bp)
1640 {
1641 	struct lofi_state *lsp;
1642 	offset_t	offset;
1643 	minor_t		part;
1644 	diskaddr_t	p_lba;
1645 	diskaddr_t	p_nblks;
1646 	int		shift;
1647 
1648 	/*
1649 	 * We cannot just do I/O here, because the current thread
1650 	 * _might_ end up back in here because the underlying filesystem
1651 	 * wants a buffer, which eventually gets into bio_recycle and
1652 	 * might call into lofi to write out a delayed-write buffer.
1653 	 * This is bad if the filesystem above lofi is the same as below.
1654 	 *
1655 	 * We could come up with a complex strategy using threads to
1656 	 * do the I/O asynchronously, or we could use task queues. task
1657 	 * queues were incredibly easy so they win.
1658 	 */
1659 
1660 	lsp = ddi_get_soft_state(lofi_statep,
1661 	    LOFI_MINOR2ID(getminor(bp->b_edev)));
1662 	part = LOFI_PART(getminor(bp->b_edev));
1663 
1664 	if (lsp == NULL) {
1665 		bioerror(bp, ENXIO);
1666 		biodone(bp);
1667 		return (0);
1668 	}
1669 
1670 	/* Check if we are closing. */
1671 	mutex_enter(&lsp->ls_vp_lock);
1672 	if (lsp->ls_vp == NULL || lsp->ls_vp_closereq) {
1673 		mutex_exit(&lsp->ls_vp_lock);
1674 		bioerror(bp, EIO);
1675 		biodone(bp);
1676 		return (0);
1677 	}
1678 	mutex_exit(&lsp->ls_vp_lock);
1679 
1680 	shift = lsp->ls_lbshift;
1681 	p_lba = 0;
1682 	p_nblks = lsp->ls_vp_size >> shift;
1683 
1684 	if (lsp->ls_cmlbhandle != NULL) {
1685 		if (cmlb_partinfo(lsp->ls_cmlbhandle, part, &p_nblks, &p_lba,
1686 		    NULL, NULL, 0)) {
1687 			bioerror(bp, ENXIO);
1688 			biodone(bp);
1689 			return (0);
1690 		}
1691 	}
1692 
1693 	/* start block past partition end? */
1694 	if (bp->b_lblkno > p_nblks) {
1695 		bioerror(bp, ENXIO);
1696 		biodone(bp);
1697 		return (0);
1698 	}
1699 
1700 	offset = (bp->b_lblkno+p_lba) << shift;	/* offset within file */
1701 
1702 	mutex_enter(&lsp->ls_vp_lock);
1703 	if (lsp->ls_crypto_enabled) {
1704 		/* encrypted data really begins after crypto header */
1705 		offset += lsp->ls_crypto_offset;
1706 	}
1707 
1708 	/* make sure we will not pass the file or partition size */
1709 	if (offset == lsp->ls_vp_size ||
1710 	    offset == (((p_lba + p_nblks) << shift) + lsp->ls_crypto_offset)) {
1711 		/* EOF */
1712 		if ((bp->b_flags & B_READ) != 0) {
1713 			bp->b_resid = bp->b_bcount;
1714 			bioerror(bp, 0);
1715 		} else {
1716 			/* writes should fail */
1717 			bioerror(bp, ENXIO);
1718 		}
1719 		biodone(bp);
1720 		mutex_exit(&lsp->ls_vp_lock);
1721 		return (0);
1722 	}
1723 	if ((offset > lsp->ls_vp_size) ||
1724 	    (offset > (((p_lba + p_nblks) << shift) + lsp->ls_crypto_offset)) ||
1725 	    ((offset + bp->b_bcount) > ((p_lba + p_nblks) << shift))) {
1726 		bioerror(bp, ENXIO);
1727 		biodone(bp);
1728 		mutex_exit(&lsp->ls_vp_lock);
1729 		return (0);
1730 	}
1731 
1732 	mutex_exit(&lsp->ls_vp_lock);
1733 
1734 	if (lsp->ls_kstat) {
1735 		mutex_enter(lsp->ls_kstat->ks_lock);
1736 		kstat_waitq_enter(KSTAT_IO_PTR(lsp->ls_kstat));
1737 		mutex_exit(lsp->ls_kstat->ks_lock);
1738 	}
1739 	bp->b_private = (void *)(uintptr_t)p_lba;	/* partition start */
1740 	(void) taskq_dispatch(lsp->ls_taskq, lofi_strategy_task, bp, KM_SLEEP);
1741 	return (0);
1742 }
1743 
1744 /*ARGSUSED2*/
1745 static int
1746 lofi_read(dev_t dev, struct uio *uio, struct cred *credp)
1747 {
1748 	if (getminor(dev) == 0)
1749 		return (EINVAL);
1750 	UIO_CHECK(uio);
1751 	return (physio(lofi_strategy, NULL, dev, B_READ, minphys, uio));
1752 }
1753 
1754 /*ARGSUSED2*/
1755 static int
1756 lofi_write(dev_t dev, struct uio *uio, struct cred *credp)
1757 {
1758 	if (getminor(dev) == 0)
1759 		return (EINVAL);
1760 	UIO_CHECK(uio);
1761 	return (physio(lofi_strategy, NULL, dev, B_WRITE, minphys, uio));
1762 }
1763 
1764 /*ARGSUSED2*/
1765 static int
1766 lofi_aread(dev_t dev, struct aio_req *aio, struct cred *credp)
1767 {
1768 	if (getminor(dev) == 0)
1769 		return (EINVAL);
1770 	UIO_CHECK(aio->aio_uio);
1771 	return (aphysio(lofi_strategy, anocancel, dev, B_READ, minphys, aio));
1772 }
1773 
1774 /*ARGSUSED2*/
1775 static int
1776 lofi_awrite(dev_t dev, struct aio_req *aio, struct cred *credp)
1777 {
1778 	if (getminor(dev) == 0)
1779 		return (EINVAL);
1780 	UIO_CHECK(aio->aio_uio);
1781 	return (aphysio(lofi_strategy, anocancel, dev, B_WRITE, minphys, aio));
1782 }
1783 
1784 /*ARGSUSED*/
1785 static int
1786 lofi_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
1787 {
1788 	struct lofi_state *lsp;
1789 	dev_t	dev = (dev_t)arg;
1790 	int instance;
1791 
1792 	instance = LOFI_MINOR2ID(getminor(dev));
1793 	switch (infocmd) {
1794 	case DDI_INFO_DEVT2DEVINFO:
1795 		lsp = ddi_get_soft_state(lofi_statep, instance);
1796 		if (lsp == NULL)
1797 			return (DDI_FAILURE);
1798 		*result = lsp->ls_dip;
1799 		return (DDI_SUCCESS);
1800 	case DDI_INFO_DEVT2INSTANCE:
1801 		*result = (void *) (intptr_t)instance;
1802 		return (DDI_SUCCESS);
1803 	}
1804 	return (DDI_FAILURE);
1805 }
1806 
1807 static int
1808 lofi_create_minor_nodes(struct lofi_state *lsp, boolean_t labeled)
1809 {
1810 	int error = 0;
1811 	int instance = ddi_get_instance(lsp->ls_dip);
1812 
1813 	if (labeled == B_TRUE) {
1814 		cmlb_alloc_handle(&lsp->ls_cmlbhandle);
1815 		error = cmlb_attach(lsp->ls_dip, &lofi_tg_ops, DTYPE_DIRECT,
1816 		    B_FALSE, B_FALSE, DDI_NT_BLOCK_CHAN,
1817 		    CMLB_CREATE_P0_MINOR_NODE, lsp->ls_cmlbhandle, (void *)1);
1818 
1819 		if (error != DDI_SUCCESS) {
1820 			cmlb_free_handle(&lsp->ls_cmlbhandle);
1821 			lsp->ls_cmlbhandle = NULL;
1822 			error = ENXIO;
1823 		}
1824 	} else {
1825 		/* create minor nodes */
1826 		error = ddi_create_minor_node(lsp->ls_dip, LOFI_BLOCK_NODE,
1827 		    S_IFBLK, LOFI_ID2MINOR(instance), DDI_PSEUDO, 0);
1828 		if (error == DDI_SUCCESS) {
1829 			error = ddi_create_minor_node(lsp->ls_dip,
1830 			    LOFI_CHAR_NODE, S_IFCHR, LOFI_ID2MINOR(instance),
1831 			    DDI_PSEUDO, 0);
1832 			if (error != DDI_SUCCESS) {
1833 				ddi_remove_minor_node(lsp->ls_dip,
1834 				    LOFI_BLOCK_NODE);
1835 				error = ENXIO;
1836 			}
1837 		} else
1838 			error = ENXIO;
1839 	}
1840 	return (error);
1841 }
1842 
1843 static int
1844 lofi_zone_bind(struct lofi_state *lsp)
1845 {
1846 	int error = 0;
1847 
1848 	mutex_enter(&curproc->p_lock);
1849 	if ((error = rctl_incr_lofi(curproc, curproc->p_zone, 1)) != 0) {
1850 		mutex_exit(&curproc->p_lock);
1851 		return (error);
1852 	}
1853 	mutex_exit(&curproc->p_lock);
1854 
1855 	if (ddi_prop_update_string(DDI_DEV_T_NONE, lsp->ls_dip, ZONE_PROP_NAME,
1856 	    (char *)curproc->p_zone->zone_name) != DDI_PROP_SUCCESS) {
1857 		rctl_decr_lofi(curproc->p_zone, 1);
1858 		error = EINVAL;
1859 	} else {
1860 		zone_init_ref(&lsp->ls_zone);
1861 		zone_hold_ref(curzone, &lsp->ls_zone, ZONE_REF_LOFI);
1862 	}
1863 	return (error);
1864 }
1865 
1866 static void
1867 lofi_zone_unbind(struct lofi_state *lsp)
1868 {
1869 	(void) ddi_prop_remove(DDI_DEV_T_NONE, lsp->ls_dip, ZONE_PROP_NAME);
1870 	rctl_decr_lofi(curproc->p_zone, 1);
1871 	zone_rele_ref(&lsp->ls_zone, ZONE_REF_LOFI);
1872 }
1873 
1874 static int
1875 lofi_online_dev(dev_info_t *dip)
1876 {
1877 	boolean_t labeled;
1878 	int	error;
1879 	int	instance = ddi_get_instance(dip);
1880 	struct lofi_state *lsp;
1881 
1882 	labeled = B_FALSE;
1883 	if (ddi_prop_exists(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS, "labeled"))
1884 		labeled = B_TRUE;
1885 
1886 	/* lsp alloc+init, soft state is freed in lofi_detach */
1887 	error = ddi_soft_state_zalloc(lofi_statep, instance);
1888 	if (error == DDI_FAILURE) {
1889 		return (ENOMEM);
1890 	}
1891 
1892 	lsp = ddi_get_soft_state(lofi_statep, instance);
1893 	lsp->ls_dip = dip;
1894 
1895 	if ((error = lofi_zone_bind(lsp)) != 0)
1896 		goto err;
1897 
1898 	cv_init(&lsp->ls_vp_cv, NULL, CV_DRIVER, NULL);
1899 	mutex_init(&lsp->ls_comp_cache_lock, NULL, MUTEX_DRIVER, NULL);
1900 	mutex_init(&lsp->ls_comp_bufs_lock, NULL, MUTEX_DRIVER, NULL);
1901 	mutex_init(&lsp->ls_kstat_lock, NULL, MUTEX_DRIVER, NULL);
1902 	mutex_init(&lsp->ls_vp_lock, NULL, MUTEX_DRIVER, NULL);
1903 
1904 	if ((error = lofi_create_minor_nodes(lsp, labeled)) != 0) {
1905 		lofi_zone_unbind(lsp);
1906 		goto lerr;
1907 	}
1908 
1909 	/* driver handles kernel-issued IOCTLs */
1910 	if (ddi_prop_create(DDI_DEV_T_NONE, dip, DDI_PROP_CANSLEEP,
1911 	    DDI_KERNEL_IOCTL, NULL, 0) != DDI_PROP_SUCCESS) {
1912 		error = DDI_FAILURE;
1913 		goto merr;
1914 	}
1915 
1916 	lsp->ls_kstat = kstat_create_zone(LOFI_DRIVER_NAME, instance,
1917 	    NULL, "disk", KSTAT_TYPE_IO, 1, 0, getzoneid());
1918 	if (lsp->ls_kstat == NULL) {
1919 		(void) ddi_prop_remove(DDI_DEV_T_NONE, lsp->ls_dip,
1920 		    DDI_KERNEL_IOCTL);
1921 		error = ENOMEM;
1922 		goto merr;
1923 	}
1924 
1925 	lsp->ls_kstat->ks_lock = &lsp->ls_kstat_lock;
1926 	kstat_zone_add(lsp->ls_kstat, GLOBAL_ZONEID);
1927 	kstat_install(lsp->ls_kstat);
1928 	return (DDI_SUCCESS);
1929 merr:
1930 	if (lsp->ls_cmlbhandle != NULL) {
1931 		cmlb_detach(lsp->ls_cmlbhandle, 0);
1932 		cmlb_free_handle(&lsp->ls_cmlbhandle);
1933 	}
1934 	ddi_remove_minor_node(dip, NULL);
1935 	lofi_zone_unbind(lsp);
1936 lerr:
1937 	mutex_destroy(&lsp->ls_comp_cache_lock);
1938 	mutex_destroy(&lsp->ls_comp_bufs_lock);
1939 	mutex_destroy(&lsp->ls_kstat_lock);
1940 	mutex_destroy(&lsp->ls_vp_lock);
1941 	cv_destroy(&lsp->ls_vp_cv);
1942 err:
1943 	ddi_soft_state_free(lofi_statep, instance);
1944 	return (error);
1945 }
1946 
1947 static int
1948 lofi_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
1949 {
1950 	int	rv;
1951 	int	instance = ddi_get_instance(dip);
1952 	struct lofi_state *lsp;
1953 
1954 	if (cmd != DDI_ATTACH)
1955 		return (DDI_FAILURE);
1956 
1957 	/*
1958 	 * Instance 0 is control instance, attaching control instance
1959 	 * will set the lofi up and ready.
1960 	 */
1961 	if (instance == 0) {
1962 		rv = ddi_soft_state_zalloc(lofi_statep, 0);
1963 		if (rv == DDI_FAILURE) {
1964 			return (DDI_FAILURE);
1965 		}
1966 		lsp = ddi_get_soft_state(lofi_statep, instance);
1967 		rv = ddi_create_minor_node(dip, LOFI_CTL_NODE, S_IFCHR, 0,
1968 		    DDI_PSEUDO, 0);
1969 		if (rv == DDI_FAILURE) {
1970 			ddi_soft_state_free(lofi_statep, 0);
1971 			return (DDI_FAILURE);
1972 		}
1973 		/* driver handles kernel-issued IOCTLs */
1974 		if (ddi_prop_create(DDI_DEV_T_NONE, dip, DDI_PROP_CANSLEEP,
1975 		    DDI_KERNEL_IOCTL, NULL, 0) != DDI_PROP_SUCCESS) {
1976 			ddi_remove_minor_node(dip, NULL);
1977 			ddi_soft_state_free(lofi_statep, 0);
1978 			return (DDI_FAILURE);
1979 		}
1980 
1981 		zone_key_create(&lofi_zone_key, NULL, lofi_zone_shutdown, NULL);
1982 
1983 		lsp->ls_dip = dip;
1984 	} else {
1985 		if (lofi_online_dev(dip) == DDI_FAILURE)
1986 			return (DDI_FAILURE);
1987 	}
1988 
1989 	ddi_report_dev(dip);
1990 	return (DDI_SUCCESS);
1991 }
1992 
1993 static int
1994 lofi_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
1995 {
1996 	struct lofi_state *lsp;
1997 	int instance = ddi_get_instance(dip);
1998 
1999 	if (cmd != DDI_DETACH)
2000 		return (DDI_FAILURE);
2001 
2002 	/*
2003 	 * If the instance is not 0, release state.
2004 	 * The instance 0 is control device, we can not detach it
2005 	 * before other instances are detached.
2006 	 */
2007 	if (instance != 0) {
2008 		lsp = ddi_get_soft_state(lofi_statep, instance);
2009 		if (lsp != NULL && lsp->ls_vp_ready == B_FALSE) {
2010 			ddi_soft_state_free(lofi_statep, instance);
2011 			return (DDI_SUCCESS);
2012 		} else
2013 			return (DDI_FAILURE);
2014 	}
2015 	mutex_enter(&lofi_lock);
2016 
2017 	if (!list_is_empty(&lofi_list)) {
2018 		mutex_exit(&lofi_lock);
2019 		return (DDI_FAILURE);
2020 	}
2021 
2022 	ddi_remove_minor_node(dip, NULL);
2023 	ddi_prop_remove_all(dip);
2024 
2025 	mutex_exit(&lofi_lock);
2026 
2027 	if (zone_key_delete(lofi_zone_key) != 0)
2028 		cmn_err(CE_WARN, "failed to delete zone key");
2029 
2030 	ddi_soft_state_free(lofi_statep, 0);
2031 
2032 	return (DDI_SUCCESS);
2033 }
2034 
2035 /*
2036  * With the addition of encryption, we must be careful that encryption key is
2037  * wiped before kernel's data structures are freed so it cannot accidentally
2038  * slip out to userland through uninitialized data elsewhere.
2039  */
2040 static void
2041 free_lofi_ioctl(struct lofi_ioctl *klip)
2042 {
2043 	/* Make sure this encryption key doesn't stick around */
2044 	bzero(klip->li_key, sizeof (klip->li_key));
2045 	kmem_free(klip, sizeof (struct lofi_ioctl));
2046 }
2047 
2048 /*
2049  * These two functions simplify the rest of the ioctls that need to copyin/out
2050  * the lofi_ioctl structure.
2051  */
2052 int
2053 copy_in_lofi_ioctl(const struct lofi_ioctl *ulip, struct lofi_ioctl **klipp,
2054     int flag)
2055 {
2056 	struct lofi_ioctl *klip;
2057 	int	error;
2058 
2059 	klip = *klipp = kmem_alloc(sizeof (struct lofi_ioctl), KM_SLEEP);
2060 	error = ddi_copyin(ulip, klip, sizeof (struct lofi_ioctl), flag);
2061 	if (error)
2062 		goto err;
2063 
2064 	/* ensure NULL termination */
2065 	klip->li_filename[MAXPATHLEN-1] = '\0';
2066 	klip->li_devpath[MAXPATHLEN-1] = '\0';
2067 	klip->li_algorithm[MAXALGLEN-1] = '\0';
2068 	klip->li_cipher[CRYPTO_MAX_MECH_NAME-1] = '\0';
2069 	klip->li_iv_cipher[CRYPTO_MAX_MECH_NAME-1] = '\0';
2070 
2071 	if (klip->li_id > L_MAXMIN32) {
2072 		error = EINVAL;
2073 		goto err;
2074 	}
2075 
2076 	return (0);
2077 
2078 err:
2079 	free_lofi_ioctl(klip);
2080 	return (error);
2081 }
2082 
2083 int
2084 copy_out_lofi_ioctl(const struct lofi_ioctl *klip, struct lofi_ioctl *ulip,
2085     int flag)
2086 {
2087 	int	error;
2088 
2089 	/*
2090 	 * NOTE: Do NOT copy the crypto_key_t "back" to userland.
2091 	 * This ensures that an attacker can't trivially find the
2092 	 * key for a mapping just by issuing the ioctl.
2093 	 *
2094 	 * It can still be found by poking around in kmem with mdb(1),
2095 	 * but there is no point in making it easy when the info isn't
2096 	 * of any use in this direction anyway.
2097 	 *
2098 	 * Either way we don't actually have the raw key stored in
2099 	 * a form that we can get it anyway, since we just used it
2100 	 * to create a ctx template and didn't keep "the original".
2101 	 */
2102 	error = ddi_copyout(klip, ulip, sizeof (struct lofi_ioctl), flag);
2103 	if (error)
2104 		return (EFAULT);
2105 	return (0);
2106 }
2107 
2108 static int
2109 lofi_access(struct lofi_state *lsp)
2110 {
2111 	ASSERT(MUTEX_HELD(&lofi_lock));
2112 	if (INGLOBALZONE(curproc) || lsp->ls_zone.zref_zone == curzone)
2113 		return (0);
2114 	return (EPERM);
2115 }
2116 
2117 /*
2118  * Find the lofi state for the given filename. We compare by vnode to
2119  * allow the global zone visibility into NGZ lofi nodes.
2120  */
2121 static int
2122 file_to_lofi_nocheck(char *filename, boolean_t readonly,
2123     struct lofi_state **lspp)
2124 {
2125 	struct lofi_state *lsp;
2126 	vnode_t *vp = NULL;
2127 	int err = 0;
2128 	int rdfiles = 0;
2129 
2130 	ASSERT(MUTEX_HELD(&lofi_lock));
2131 
2132 	if ((err = lookupname(filename, UIO_SYSSPACE, FOLLOW,
2133 	    NULLVPP, &vp)) != 0)
2134 		goto out;
2135 
2136 	if (vp->v_type == VREG) {
2137 		vnode_t *realvp;
2138 		if (VOP_REALVP(vp, &realvp, NULL) == 0) {
2139 			VN_HOLD(realvp);
2140 			VN_RELE(vp);
2141 			vp = realvp;
2142 		}
2143 	}
2144 
2145 	for (lsp = list_head(&lofi_list); lsp != NULL;
2146 	    lsp = list_next(&lofi_list, lsp)) {
2147 		if (lsp->ls_vp == vp) {
2148 			if (lspp != NULL)
2149 				*lspp = lsp;
2150 			if (lsp->ls_readonly) {
2151 				rdfiles++;
2152 				/* Skip if '-r' is specified */
2153 				if (readonly)
2154 					continue;
2155 			}
2156 			goto out;
2157 		}
2158 	}
2159 
2160 	err = ENOENT;
2161 
2162 	/*
2163 	 * If a filename is given as an argument for lofi_unmap, we shouldn't
2164 	 * allow unmap if there are multiple read-only lofi devices associated
2165 	 * with this file.
2166 	 */
2167 	if (lspp != NULL) {
2168 		if (rdfiles == 1)
2169 			err = 0;
2170 		else if (rdfiles > 1)
2171 			err = EBUSY;
2172 	}
2173 
2174 out:
2175 	if (vp != NULL)
2176 		VN_RELE(vp);
2177 	return (err);
2178 }
2179 
2180 /*
2181  * Find the minor for the given filename, checking the zone can access
2182  * it.
2183  */
2184 static int
2185 file_to_lofi(char *filename, boolean_t readonly, struct lofi_state **lspp)
2186 {
2187 	int err = 0;
2188 
2189 	ASSERT(MUTEX_HELD(&lofi_lock));
2190 
2191 	if ((err = file_to_lofi_nocheck(filename, readonly, lspp)) != 0)
2192 		return (err);
2193 
2194 	if ((err = lofi_access(*lspp)) != 0)
2195 		return (err);
2196 
2197 	return (0);
2198 }
2199 
2200 /*
2201  * Fakes up a disk geometry based on the size of the file. This is needed
2202  * to support newfs on traditional lofi device, but also will provide
2203  * geometry hint for cmlb.
2204  */
2205 static void
2206 fake_disk_geometry(struct lofi_state *lsp)
2207 {
2208 	u_offset_t dsize = lsp->ls_vp_size - lsp->ls_crypto_offset;
2209 
2210 	/* dk_geom - see dkio(7I) */
2211 	/*
2212 	 * dkg_ncyl _could_ be set to one here (one big cylinder with gobs
2213 	 * of sectors), but that breaks programs like fdisk which want to
2214 	 * partition a disk by cylinder. With one cylinder, you can't create
2215 	 * an fdisk partition and put pcfs on it for testing (hard to pick
2216 	 * a number between one and one).
2217 	 *
2218 	 * The cheezy floppy test is an attempt to not have too few cylinders
2219 	 * for a small file, or so many on a big file that you waste space
2220 	 * for backup superblocks or cylinder group structures.
2221 	 */
2222 	bzero(&lsp->ls_dkg, sizeof (lsp->ls_dkg));
2223 	if (dsize < (2 * 1024 * 1024)) /* floppy? */
2224 		lsp->ls_dkg.dkg_ncyl = dsize / (100 * 1024);
2225 	else
2226 		lsp->ls_dkg.dkg_ncyl = dsize / (300 * 1024);
2227 	/* in case file file is < 100k */
2228 	if (lsp->ls_dkg.dkg_ncyl == 0)
2229 		lsp->ls_dkg.dkg_ncyl = 1;
2230 
2231 	lsp->ls_dkg.dkg_pcyl = lsp->ls_dkg.dkg_ncyl;
2232 	lsp->ls_dkg.dkg_nhead = 1;
2233 	lsp->ls_dkg.dkg_rpm = 7200;
2234 
2235 	lsp->ls_dkg.dkg_nsect = dsize /
2236 	    (lsp->ls_dkg.dkg_ncyl << lsp->ls_pbshift);
2237 }
2238 
2239 /*
2240  * build vtoc - see dkio(7I)
2241  *
2242  * Fakes one big partition based on the size of the file. This is needed
2243  * because we allow newfs'ing the traditional lofi device and newfs will
2244  * do several disk ioctls to figure out the geometry and partition information.
2245  * It uses that information to determine the parameters to pass to mkfs.
2246  */
2247 static void
2248 fake_disk_vtoc(struct lofi_state *lsp, struct vtoc *vt)
2249 {
2250 	bzero(vt, sizeof (struct vtoc));
2251 	vt->v_sanity = VTOC_SANE;
2252 	vt->v_version = V_VERSION;
2253 	(void) strncpy(vt->v_volume, LOFI_DRIVER_NAME,
2254 	    sizeof (vt->v_volume));
2255 	vt->v_sectorsz = 1 << lsp->ls_pbshift;
2256 	vt->v_nparts = 1;
2257 	vt->v_part[0].p_tag = V_UNASSIGNED;
2258 
2259 	/*
2260 	 * A compressed file is read-only, other files can
2261 	 * be read-write
2262 	 */
2263 	if (lsp->ls_uncomp_seg_sz > 0) {
2264 		vt->v_part[0].p_flag = V_UNMNT | V_RONLY;
2265 	} else {
2266 		vt->v_part[0].p_flag = V_UNMNT;
2267 	}
2268 	vt->v_part[0].p_start = (daddr_t)0;
2269 	/*
2270 	 * The partition size cannot just be the number of sectors, because
2271 	 * that might not end on a cylinder boundary. And if that's the case,
2272 	 * newfs/mkfs will print a scary warning. So just figure the size
2273 	 * based on the number of cylinders and sectors/cylinder.
2274 	 */
2275 	vt->v_part[0].p_size = lsp->ls_dkg.dkg_pcyl *
2276 	    lsp->ls_dkg.dkg_nsect * lsp->ls_dkg.dkg_nhead;
2277 }
2278 
2279 /*
2280  * build dk_cinfo - see dkio(7I)
2281  */
2282 static void
2283 fake_disk_info(dev_t dev, struct dk_cinfo *ci)
2284 {
2285 	bzero(ci, sizeof (struct dk_cinfo));
2286 	(void) strlcpy(ci->dki_cname, LOFI_DRIVER_NAME, sizeof (ci->dki_cname));
2287 	ci->dki_ctype = DKC_SCSI_CCS;
2288 	(void) strlcpy(ci->dki_dname, LOFI_DRIVER_NAME, sizeof (ci->dki_dname));
2289 	ci->dki_unit = LOFI_MINOR2ID(getminor(dev));
2290 	ci->dki_partition = LOFI_PART(getminor(dev));
2291 	/*
2292 	 * newfs uses this to set maxcontig. Must not be < 16, or it
2293 	 * will be 0 when newfs multiplies it by DEV_BSIZE and divides
2294 	 * it by the block size. Then tunefs doesn't work because
2295 	 * maxcontig is 0.
2296 	 */
2297 	ci->dki_maxtransfer = 16;
2298 }
2299 
2300 /*
2301  * map in a compressed file
2302  *
2303  * Read in the header and the index that follows.
2304  *
2305  * The header is as follows -
2306  *
2307  * Signature (name of the compression algorithm)
2308  * Compression segment size (a multiple of 512)
2309  * Number of index entries
2310  * Size of the last block
2311  * The array containing the index entries
2312  *
2313  * The header information is always stored in
2314  * network byte order on disk.
2315  */
2316 static int
2317 lofi_map_compressed_file(struct lofi_state *lsp, char *buf)
2318 {
2319 	uint32_t index_sz, header_len, i;
2320 	ssize_t	resid;
2321 	enum uio_rw rw;
2322 	char *tbuf = buf;
2323 	int error;
2324 
2325 	/* The signature has already been read */
2326 	tbuf += sizeof (lsp->ls_comp_algorithm);
2327 	bcopy(tbuf, &(lsp->ls_uncomp_seg_sz), sizeof (lsp->ls_uncomp_seg_sz));
2328 	lsp->ls_uncomp_seg_sz = ntohl(lsp->ls_uncomp_seg_sz);
2329 
2330 	/*
2331 	 * The compressed segment size must be a power of 2
2332 	 */
2333 	if (lsp->ls_uncomp_seg_sz < DEV_BSIZE ||
2334 	    !ISP2(lsp->ls_uncomp_seg_sz))
2335 		return (EINVAL);
2336 
2337 	for (i = 0; !((lsp->ls_uncomp_seg_sz >> i) & 1); i++)
2338 		;
2339 
2340 	lsp->ls_comp_seg_shift = i;
2341 
2342 	tbuf += sizeof (lsp->ls_uncomp_seg_sz);
2343 	bcopy(tbuf, &(lsp->ls_comp_index_sz), sizeof (lsp->ls_comp_index_sz));
2344 	lsp->ls_comp_index_sz = ntohl(lsp->ls_comp_index_sz);
2345 
2346 	tbuf += sizeof (lsp->ls_comp_index_sz);
2347 	bcopy(tbuf, &(lsp->ls_uncomp_last_seg_sz),
2348 	    sizeof (lsp->ls_uncomp_last_seg_sz));
2349 	lsp->ls_uncomp_last_seg_sz = ntohl(lsp->ls_uncomp_last_seg_sz);
2350 
2351 	/*
2352 	 * Compute the total size of the uncompressed data
2353 	 * for use in fake_disk_geometry and other calculations.
2354 	 * Disk geometry has to be faked with respect to the
2355 	 * actual uncompressed data size rather than the
2356 	 * compressed file size.
2357 	 */
2358 	lsp->ls_vp_size =
2359 	    (u_offset_t)(lsp->ls_comp_index_sz - 2) * lsp->ls_uncomp_seg_sz
2360 	    + lsp->ls_uncomp_last_seg_sz;
2361 
2362 	/*
2363 	 * Index size is rounded up to DEV_BSIZE for ease
2364 	 * of segmapping
2365 	 */
2366 	index_sz = sizeof (*lsp->ls_comp_seg_index) * lsp->ls_comp_index_sz;
2367 	header_len = sizeof (lsp->ls_comp_algorithm) +
2368 	    sizeof (lsp->ls_uncomp_seg_sz) +
2369 	    sizeof (lsp->ls_comp_index_sz) +
2370 	    sizeof (lsp->ls_uncomp_last_seg_sz);
2371 	lsp->ls_comp_offbase = header_len + index_sz;
2372 
2373 	index_sz += header_len;
2374 	index_sz = roundup(index_sz, DEV_BSIZE);
2375 
2376 	lsp->ls_comp_index_data = kmem_alloc(index_sz, KM_SLEEP);
2377 	lsp->ls_comp_index_data_sz = index_sz;
2378 
2379 	/*
2380 	 * Read in the index -- this has a side-effect
2381 	 * of reading in the header as well
2382 	 */
2383 	rw = UIO_READ;
2384 	error = vn_rdwr(rw, lsp->ls_vp, lsp->ls_comp_index_data, index_sz,
2385 	    0, UIO_SYSSPACE, 0, RLIM64_INFINITY, kcred, &resid);
2386 
2387 	if (error != 0)
2388 		return (error);
2389 
2390 	/* Skip the header, this is where the index really begins */
2391 	lsp->ls_comp_seg_index =
2392 	    /*LINTED*/
2393 	    (uint64_t *)(lsp->ls_comp_index_data + header_len);
2394 
2395 	/*
2396 	 * Now recompute offsets in the index to account for
2397 	 * the header length
2398 	 */
2399 	for (i = 0; i < lsp->ls_comp_index_sz; i++) {
2400 		lsp->ls_comp_seg_index[i] = lsp->ls_comp_offbase +
2401 		    BE_64(lsp->ls_comp_seg_index[i]);
2402 	}
2403 
2404 	return (error);
2405 }
2406 
2407 static int
2408 lofi_init_crypto(struct lofi_state *lsp, struct lofi_ioctl *klip)
2409 {
2410 	struct crypto_meta chead;
2411 	char buf[DEV_BSIZE];
2412 	ssize_t	resid;
2413 	char *marker;
2414 	int error;
2415 	int ret;
2416 	int i;
2417 
2418 	if (!klip->li_crypto_enabled)
2419 		return (0);
2420 
2421 	/*
2422 	 * All current algorithms have a max of 448 bits.
2423 	 */
2424 	if (klip->li_iv_len > CRYPTO_BITS2BYTES(512))
2425 		return (EINVAL);
2426 
2427 	if (CRYPTO_BITS2BYTES(klip->li_key_len) > sizeof (klip->li_key))
2428 		return (EINVAL);
2429 
2430 	lsp->ls_crypto_enabled = klip->li_crypto_enabled;
2431 
2432 	mutex_init(&lsp->ls_crypto_lock, NULL, MUTEX_DRIVER, NULL);
2433 
2434 	lsp->ls_mech.cm_type = crypto_mech2id(klip->li_cipher);
2435 	if (lsp->ls_mech.cm_type == CRYPTO_MECH_INVALID) {
2436 		cmn_err(CE_WARN, "invalid cipher %s requested for %s",
2437 		    klip->li_cipher, klip->li_filename);
2438 		return (EINVAL);
2439 	}
2440 
2441 	/* this is just initialization here */
2442 	lsp->ls_mech.cm_param = NULL;
2443 	lsp->ls_mech.cm_param_len = 0;
2444 
2445 	lsp->ls_iv_type = klip->li_iv_type;
2446 	lsp->ls_iv_mech.cm_type = crypto_mech2id(klip->li_iv_cipher);
2447 	if (lsp->ls_iv_mech.cm_type == CRYPTO_MECH_INVALID) {
2448 		cmn_err(CE_WARN, "invalid iv cipher %s requested"
2449 		    " for %s", klip->li_iv_cipher, klip->li_filename);
2450 		return (EINVAL);
2451 	}
2452 
2453 	/* iv mech must itself take a null iv */
2454 	lsp->ls_iv_mech.cm_param = NULL;
2455 	lsp->ls_iv_mech.cm_param_len = 0;
2456 	lsp->ls_iv_len = klip->li_iv_len;
2457 
2458 	/*
2459 	 * Create ctx using li_cipher & the raw li_key after checking
2460 	 * that it isn't a weak key.
2461 	 */
2462 	lsp->ls_key.ck_format = CRYPTO_KEY_RAW;
2463 	lsp->ls_key.ck_length = klip->li_key_len;
2464 	lsp->ls_key.ck_data = kmem_alloc(
2465 	    CRYPTO_BITS2BYTES(lsp->ls_key.ck_length), KM_SLEEP);
2466 	bcopy(klip->li_key, lsp->ls_key.ck_data,
2467 	    CRYPTO_BITS2BYTES(lsp->ls_key.ck_length));
2468 
2469 	ret = crypto_key_check(&lsp->ls_mech, &lsp->ls_key);
2470 	if (ret != CRYPTO_SUCCESS) {
2471 		cmn_err(CE_WARN, "weak key check failed for cipher "
2472 		    "%s on file %s (0x%x)", klip->li_cipher,
2473 		    klip->li_filename, ret);
2474 		return (EINVAL);
2475 	}
2476 
2477 	error = vn_rdwr(UIO_READ, lsp->ls_vp, buf, DEV_BSIZE,
2478 	    CRYOFF, UIO_SYSSPACE, 0, RLIM64_INFINITY, kcred, &resid);
2479 	if (error != 0)
2480 		return (error);
2481 
2482 	/*
2483 	 * This is the case where the header in the lofi image is already
2484 	 * initialized to indicate it is encrypted.
2485 	 */
2486 	if (strncmp(buf, lofi_crypto_magic, sizeof (lofi_crypto_magic)) == 0) {
2487 		/*
2488 		 * The encryption header information is laid out this way:
2489 		 *	6 bytes:	hex "CFLOFI"
2490 		 *	2 bytes:	version = 0 ... for now
2491 		 *	96 bytes:	reserved1 (not implemented yet)
2492 		 *	4 bytes:	data_sector = 2 ... for now
2493 		 *	more...		not implemented yet
2494 		 */
2495 
2496 		marker = buf;
2497 
2498 		/* copy the magic */
2499 		bcopy(marker, lsp->ls_crypto.magic,
2500 		    sizeof (lsp->ls_crypto.magic));
2501 		marker += sizeof (lsp->ls_crypto.magic);
2502 
2503 		/* read the encryption version number */
2504 		bcopy(marker, &(lsp->ls_crypto.version),
2505 		    sizeof (lsp->ls_crypto.version));
2506 		lsp->ls_crypto.version = ntohs(lsp->ls_crypto.version);
2507 		marker += sizeof (lsp->ls_crypto.version);
2508 
2509 		/* read a chunk of reserved data */
2510 		bcopy(marker, lsp->ls_crypto.reserved1,
2511 		    sizeof (lsp->ls_crypto.reserved1));
2512 		marker += sizeof (lsp->ls_crypto.reserved1);
2513 
2514 		/* read block number where encrypted data begins */
2515 		bcopy(marker, &(lsp->ls_crypto.data_sector),
2516 		    sizeof (lsp->ls_crypto.data_sector));
2517 		lsp->ls_crypto.data_sector = ntohl(lsp->ls_crypto.data_sector);
2518 		marker += sizeof (lsp->ls_crypto.data_sector);
2519 
2520 		/* and ignore the rest until it is implemented */
2521 
2522 		lsp->ls_crypto_offset = lsp->ls_crypto.data_sector * DEV_BSIZE;
2523 		return (0);
2524 	}
2525 
2526 	/*
2527 	 * We've requested encryption, but no magic was found, so it must be
2528 	 * a new image.
2529 	 */
2530 
2531 	for (i = 0; i < sizeof (struct crypto_meta); i++) {
2532 		if (buf[i] != '\0')
2533 			return (EINVAL);
2534 	}
2535 
2536 	marker = buf;
2537 	bcopy(lofi_crypto_magic, marker, sizeof (lofi_crypto_magic));
2538 	marker += sizeof (lofi_crypto_magic);
2539 	chead.version = htons(LOFI_CRYPTO_VERSION);
2540 	bcopy(&(chead.version), marker, sizeof (chead.version));
2541 	marker += sizeof (chead.version);
2542 	marker += sizeof (chead.reserved1);
2543 	chead.data_sector = htonl(LOFI_CRYPTO_DATA_SECTOR);
2544 	bcopy(&(chead.data_sector), marker, sizeof (chead.data_sector));
2545 
2546 	/* write the header */
2547 	error = vn_rdwr(UIO_WRITE, lsp->ls_vp, buf, DEV_BSIZE,
2548 	    CRYOFF, UIO_SYSSPACE, 0, RLIM64_INFINITY, kcred, &resid);
2549 	if (error != 0)
2550 		return (error);
2551 
2552 	/* fix things up so it looks like we read this info */
2553 	bcopy(lofi_crypto_magic, lsp->ls_crypto.magic,
2554 	    sizeof (lofi_crypto_magic));
2555 	lsp->ls_crypto.version = LOFI_CRYPTO_VERSION;
2556 	lsp->ls_crypto.data_sector = LOFI_CRYPTO_DATA_SECTOR;
2557 	lsp->ls_crypto_offset = lsp->ls_crypto.data_sector * DEV_BSIZE;
2558 	return (0);
2559 }
2560 
2561 /*
2562  * Check to see if the passed in signature is a valid one.  If it is
2563  * valid, return the index into lofi_compress_table.
2564  *
2565  * Return -1 if it is invalid
2566  */
2567 static int
2568 lofi_compress_select(const char *signature)
2569 {
2570 	int i;
2571 
2572 	for (i = 0; i < LOFI_COMPRESS_FUNCTIONS; i++) {
2573 		if (strcmp(lofi_compress_table[i].l_name, signature) == 0)
2574 			return (i);
2575 	}
2576 
2577 	return (-1);
2578 }
2579 
2580 static int
2581 lofi_init_compress(struct lofi_state *lsp)
2582 {
2583 	char buf[DEV_BSIZE];
2584 	int compress_index;
2585 	ssize_t	resid;
2586 	int error;
2587 
2588 	error = vn_rdwr(UIO_READ, lsp->ls_vp, buf, DEV_BSIZE, 0, UIO_SYSSPACE,
2589 	    0, RLIM64_INFINITY, kcred, &resid);
2590 
2591 	if (error != 0)
2592 		return (error);
2593 
2594 	if ((compress_index = lofi_compress_select(buf)) == -1)
2595 		return (0);
2596 
2597 	/* compression and encryption are mutually exclusive */
2598 	if (lsp->ls_crypto_enabled)
2599 		return (ENOTSUP);
2600 
2601 	/* initialize compression info for compressed lofi */
2602 	lsp->ls_comp_algorithm_index = compress_index;
2603 	(void) strlcpy(lsp->ls_comp_algorithm,
2604 	    lofi_compress_table[compress_index].l_name,
2605 	    sizeof (lsp->ls_comp_algorithm));
2606 
2607 	/* Finally setup per-thread pre-allocated buffers */
2608 	lsp->ls_comp_bufs = kmem_zalloc(lofi_taskq_nthreads *
2609 	    sizeof (struct compbuf), KM_SLEEP);
2610 
2611 	return (lofi_map_compressed_file(lsp, buf));
2612 }
2613 
2614 /*
2615  * Allocate new or proposed id from lofi_id.
2616  *
2617  * Special cases for proposed id:
2618  * 0: not allowed, 0 is id for control device.
2619  * -1: allocate first usable id from lofi_id.
2620  * any other value is proposed value from userland
2621  *
2622  * returns DDI_SUCCESS or errno.
2623  */
2624 static int
2625 lofi_alloc_id(int *idp)
2626 {
2627 	int id, error = DDI_SUCCESS;
2628 
2629 	if (*idp == -1) {
2630 		id = id_allocff_nosleep(lofi_id);
2631 		if (id == -1) {
2632 			error = EAGAIN;
2633 			goto err;
2634 		}
2635 	} else if (*idp == 0) {
2636 		error = EINVAL;
2637 		goto err;
2638 	} else if (*idp > ((1 << (L_BITSMINOR - LOFI_CMLB_SHIFT)) - 1)) {
2639 		error = ERANGE;
2640 		goto err;
2641 	} else {
2642 		if (ddi_get_soft_state(lofi_statep, *idp) != NULL) {
2643 			error = EEXIST;
2644 			goto err;
2645 		}
2646 
2647 		id = id_alloc_specific_nosleep(lofi_id, *idp);
2648 		if (id == -1) {
2649 			error = EAGAIN;
2650 			goto err;
2651 		}
2652 	}
2653 	*idp = id;
2654 err:
2655 	return (error);
2656 }
2657 
2658 static int
2659 lofi_create_dev(struct lofi_ioctl *klip)
2660 {
2661 	dev_info_t *parent, *child;
2662 	struct lofi_state *lsp = NULL;
2663 	char namebuf[MAXNAMELEN];
2664 	int error, circ;
2665 
2666 	/* get control device */
2667 	lsp = ddi_get_soft_state(lofi_statep, 0);
2668 	parent = ddi_get_parent(lsp->ls_dip);
2669 
2670 	if ((error = lofi_alloc_id((int *)&klip->li_id)))
2671 		return (error);
2672 
2673 	(void) snprintf(namebuf, sizeof (namebuf), LOFI_DRIVER_NAME "@%d",
2674 	    klip->li_id);
2675 
2676 	ndi_devi_enter(parent, &circ);
2677 	child = ndi_devi_findchild(parent, namebuf);
2678 	ndi_devi_exit(parent, circ);
2679 
2680 	if (child == NULL) {
2681 		child = ddi_add_child(parent, LOFI_DRIVER_NAME,
2682 		    (pnode_t)DEVI_SID_NODEID, klip->li_id);
2683 		if ((error = ddi_prop_update_int(DDI_DEV_T_NONE, child,
2684 		    "instance", klip->li_id)) != DDI_PROP_SUCCESS)
2685 			goto err;
2686 
2687 		if (klip->li_labeled == B_TRUE) {
2688 			if ((error = ddi_prop_create(DDI_DEV_T_NONE, child,
2689 			    DDI_PROP_CANSLEEP, "labeled", 0, 0))
2690 			    != DDI_PROP_SUCCESS)
2691 				goto err;
2692 		}
2693 
2694 		if ((error = ndi_devi_online(child, NDI_ONLINE_ATTACH))
2695 		    != NDI_SUCCESS)
2696 			goto err;
2697 	} else {
2698 		id_free(lofi_id, klip->li_id);
2699 		error = EEXIST;
2700 		return (error);
2701 	}
2702 
2703 	goto done;
2704 
2705 err:
2706 	ddi_prop_remove_all(child);
2707 	(void) ndi_devi_offline(child, NDI_DEVI_REMOVE);
2708 	id_free(lofi_id, klip->li_id);
2709 done:
2710 
2711 	return (error);
2712 }
2713 
2714 static void
2715 lofi_create_inquiry(struct lofi_state *lsp, struct scsi_inquiry *inq)
2716 {
2717 	char *p = NULL;
2718 
2719 	(void) strlcpy(inq->inq_vid, LOFI_DRIVER_NAME, sizeof (inq->inq_vid));
2720 
2721 	mutex_enter(&lsp->ls_vp_lock);
2722 	if (lsp->ls_vp != NULL)
2723 		p = strrchr(lsp->ls_vp->v_path, '/');
2724 	if (p != NULL)
2725 		(void) strncpy(inq->inq_pid, p + 1, sizeof (inq->inq_pid));
2726 	mutex_exit(&lsp->ls_vp_lock);
2727 	(void) strlcpy(inq->inq_revision, "1.0", sizeof (inq->inq_revision));
2728 }
2729 
2730 /*
2731  * copy devlink name from event cache
2732  */
2733 static void
2734 lofi_copy_devpath(struct lofi_ioctl *klip)
2735 {
2736 	int	error;
2737 	char	namebuf[MAXNAMELEN], *str;
2738 	clock_t ticks;
2739 	nvlist_t *nvl = NULL;
2740 
2741 	if (klip->li_labeled == B_TRUE)
2742 		klip->li_devpath[0] = '\0';
2743 	else {
2744 		/* no need to wait for messages */
2745 		(void) snprintf(klip->li_devpath, sizeof (klip->li_devpath),
2746 		    "/dev/" LOFI_CHAR_NAME "/%d", klip->li_id);
2747 		return;
2748 	}
2749 
2750 	(void) snprintf(namebuf, sizeof (namebuf), "%d", klip->li_id);
2751 	ticks = ddi_get_lbolt() + LOFI_TIMEOUT * drv_usectohz(1000000);
2752 
2753 	mutex_enter(&lofi_devlink_cache.ln_lock);
2754 	error = nvlist_lookup_nvlist(lofi_devlink_cache.ln_data, namebuf, &nvl);
2755 	while (error != 0) {
2756 		error = cv_timedwait(&lofi_devlink_cache.ln_cv,
2757 		    &lofi_devlink_cache.ln_lock, ticks);
2758 		if (error == -1)
2759 			break;
2760 		error = nvlist_lookup_nvlist(lofi_devlink_cache.ln_data,
2761 		    namebuf, &nvl);
2762 	}
2763 
2764 	if (nvl != NULL) {
2765 		if (nvlist_lookup_string(nvl, DEV_NAME, &str) == 0) {
2766 			(void) strlcpy(klip->li_devpath, str,
2767 			    sizeof (klip->li_devpath));
2768 		}
2769 	}
2770 	mutex_exit(&lofi_devlink_cache.ln_lock);
2771 }
2772 
2773 /*
2774  * map a file to a minor number. Return the minor number.
2775  */
2776 static int
2777 lofi_map_file(dev_t dev, struct lofi_ioctl *ulip, int pickminor,
2778     int *rvalp, struct cred *credp, int ioctl_flag)
2779 {
2780 	int	id = -1;
2781 	struct lofi_state *lsp = NULL;
2782 	struct lofi_ioctl *klip;
2783 	int	error;
2784 	struct vnode *vp = NULL;
2785 	vattr_t	vattr;
2786 	int	flag;
2787 	char	namebuf[MAXNAMELEN];
2788 
2789 	error = copy_in_lofi_ioctl(ulip, &klip, ioctl_flag);
2790 	if (error != 0)
2791 		return (error);
2792 
2793 	mutex_enter(&lofi_lock);
2794 
2795 	if (file_to_lofi_nocheck(klip->li_filename, klip->li_readonly,
2796 	    NULL) == 0) {
2797 		error = EBUSY;
2798 		goto err;
2799 	}
2800 
2801 	flag = FREAD | FWRITE | FOFFMAX | FEXCL;
2802 	error = vn_open(klip->li_filename, UIO_SYSSPACE, flag, 0, &vp, 0, 0);
2803 	if (error) {
2804 		/* try read-only */
2805 		flag &= ~FWRITE;
2806 		error = vn_open(klip->li_filename, UIO_SYSSPACE, flag, 0,
2807 		    &vp, 0, 0);
2808 		if (error)
2809 			goto err;
2810 	}
2811 
2812 	if (!V_ISLOFIABLE(vp->v_type)) {
2813 		error = EINVAL;
2814 		goto err;
2815 	}
2816 
2817 	vattr.va_mask = AT_SIZE;
2818 	error = VOP_GETATTR(vp, &vattr, 0, credp, NULL);
2819 	if (error)
2820 		goto err;
2821 
2822 	/* the file needs to be a multiple of the block size */
2823 	if ((vattr.va_size % DEV_BSIZE) != 0) {
2824 		error = EINVAL;
2825 		goto err;
2826 	}
2827 
2828 	if (pickminor) {
2829 		klip->li_id = (uint32_t)-1;
2830 	}
2831 	if ((error = lofi_create_dev(klip)) != 0)
2832 		goto err;
2833 
2834 	id = klip->li_id;
2835 	lsp = ddi_get_soft_state(lofi_statep, id);
2836 	if (lsp == NULL)
2837 		goto err;
2838 
2839 	/*
2840 	 * from this point lofi_destroy() is used to clean up on error
2841 	 * make sure the basic data is set
2842 	 */
2843 	list_insert_tail(&lofi_list, lsp);
2844 	lsp->ls_dev = makedevice(getmajor(dev), LOFI_ID2MINOR(id));
2845 
2846 	list_create(&lsp->ls_comp_cache, sizeof (struct lofi_comp_cache),
2847 	    offsetof(struct lofi_comp_cache, lc_list));
2848 
2849 	/*
2850 	 * save open mode so file can be closed properly and vnode counts
2851 	 * updated correctly.
2852 	 */
2853 	lsp->ls_openflag = flag;
2854 
2855 	lsp->ls_vp = vp;
2856 	lsp->ls_stacked_vp = vp;
2857 
2858 	lsp->ls_vp_size = vattr.va_size;
2859 	lsp->ls_vp_comp_size = lsp->ls_vp_size;
2860 
2861 	/*
2862 	 * Try to handle stacked lofs vnodes.
2863 	 */
2864 	if (vp->v_type == VREG) {
2865 		vnode_t *realvp;
2866 
2867 		if (VOP_REALVP(vp, &realvp, NULL) == 0) {
2868 			/*
2869 			 * We need to use the realvp for uniqueness
2870 			 * checking, but keep the stacked vp for
2871 			 * LOFI_GET_FILENAME display.
2872 			 */
2873 			VN_HOLD(realvp);
2874 			lsp->ls_vp = realvp;
2875 		}
2876 	}
2877 
2878 	lsp->ls_lbshift = highbit(DEV_BSIZE) - 1;
2879 	lsp->ls_pbshift = lsp->ls_lbshift;
2880 
2881 	lsp->ls_readonly = klip->li_readonly;
2882 	lsp->ls_uncomp_seg_sz = 0;
2883 	lsp->ls_comp_algorithm[0] = '\0';
2884 	lsp->ls_crypto_offset = 0;
2885 
2886 	(void) snprintf(namebuf, sizeof (namebuf), "%s_taskq_%d",
2887 	    LOFI_DRIVER_NAME, id);
2888 	lsp->ls_taskq = taskq_create_proc(namebuf, lofi_taskq_nthreads,
2889 	    minclsyspri, 1, lofi_taskq_maxalloc, curzone->zone_zsched, 0);
2890 
2891 	if ((error = lofi_init_crypto(lsp, klip)) != 0)
2892 		goto err;
2893 
2894 	if ((error = lofi_init_compress(lsp)) != 0)
2895 		goto err;
2896 
2897 	fake_disk_geometry(lsp);
2898 
2899 	/* For unlabeled lofi add Nblocks and Size */
2900 	if (klip->li_labeled == B_FALSE) {
2901 		error = ddi_prop_update_int64(lsp->ls_dev, lsp->ls_dip,
2902 		    SIZE_PROP_NAME, lsp->ls_vp_size - lsp->ls_crypto_offset);
2903 		if (error != DDI_PROP_SUCCESS) {
2904 			error = EINVAL;
2905 			goto err;
2906 		}
2907 		error = ddi_prop_update_int64(lsp->ls_dev, lsp->ls_dip,
2908 		    NBLOCKS_PROP_NAME,
2909 		    (lsp->ls_vp_size - lsp->ls_crypto_offset) / DEV_BSIZE);
2910 		if (error != DDI_PROP_SUCCESS) {
2911 			error = EINVAL;
2912 			goto err;
2913 		}
2914 	}
2915 
2916 	/*
2917 	 * Notify we are ready to rock.
2918 	 */
2919 	mutex_enter(&lsp->ls_vp_lock);
2920 	lsp->ls_vp_ready = B_TRUE;
2921 	cv_broadcast(&lsp->ls_vp_cv);
2922 	mutex_exit(&lsp->ls_vp_lock);
2923 	mutex_exit(&lofi_lock);
2924 
2925 	lofi_copy_devpath(klip);
2926 
2927 	if (rvalp)
2928 		*rvalp = id;
2929 	(void) copy_out_lofi_ioctl(klip, ulip, ioctl_flag);
2930 	free_lofi_ioctl(klip);
2931 	return (0);
2932 
2933 err:
2934 	if (lsp != NULL) {
2935 		lofi_destroy(lsp, credp);
2936 	} else {
2937 		if (vp != NULL) {
2938 			(void) VOP_PUTPAGE(vp, 0, 0, B_FREE, credp, NULL);
2939 			(void) VOP_CLOSE(vp, flag, 1, 0, credp, NULL);
2940 			VN_RELE(vp);
2941 		}
2942 	}
2943 
2944 	mutex_exit(&lofi_lock);
2945 	free_lofi_ioctl(klip);
2946 	return (error);
2947 }
2948 
2949 /*
2950  * unmap a file.
2951  */
2952 static int
2953 lofi_unmap_file(struct lofi_ioctl *ulip, int byfilename,
2954     struct cred *credp, int ioctl_flag)
2955 {
2956 	struct lofi_state *lsp;
2957 	struct lofi_ioctl *klip;
2958 	char namebuf[MAXNAMELEN];
2959 	int err;
2960 
2961 	err = copy_in_lofi_ioctl(ulip, &klip, ioctl_flag);
2962 	if (err != 0)
2963 		return (err);
2964 
2965 	mutex_enter(&lofi_lock);
2966 	if (byfilename) {
2967 		if ((err = file_to_lofi(klip->li_filename, klip->li_readonly,
2968 		    &lsp)) != 0) {
2969 			goto done;
2970 		}
2971 	} else if (klip->li_id == 0) {
2972 		err = ENXIO;
2973 		goto done;
2974 	} else {
2975 		lsp = ddi_get_soft_state(lofi_statep, klip->li_id);
2976 	}
2977 
2978 	if (lsp == NULL || lsp->ls_vp == NULL || lofi_access(lsp) != 0) {
2979 		err = ENXIO;
2980 		goto done;
2981 	}
2982 
2983 	klip->li_id = LOFI_MINOR2ID(getminor(lsp->ls_dev));
2984 	(void) snprintf(namebuf, sizeof (namebuf), "%u", klip->li_id);
2985 
2986 	/*
2987 	 * If it's still held open, we'll do one of three things:
2988 	 *
2989 	 * If no flag is set, just return EBUSY.
2990 	 *
2991 	 * If the 'cleanup' flag is set, unmap and remove the device when
2992 	 * the last user finishes.
2993 	 *
2994 	 * If the 'force' flag is set, then we forcibly close the underlying
2995 	 * file.  Subsequent operations will fail, and the DKIOCSTATE ioctl
2996 	 * will return DKIO_DEV_GONE.  When the device is last closed, the
2997 	 * device will be cleaned up appropriately.
2998 	 *
2999 	 * This is complicated by the fact that we may have outstanding
3000 	 * dispatched I/Os.  Rather than having a single mutex to serialize all
3001 	 * I/O, we keep a count of the number of outstanding I/O requests
3002 	 * (ls_vp_iocount), as well as a flag to indicate that no new I/Os
3003 	 * should be dispatched (ls_vp_closereq).
3004 	 *
3005 	 * We set the flag, wait for the number of outstanding I/Os to reach 0,
3006 	 * and then close the underlying vnode.
3007 	 */
3008 	if (is_opened(lsp)) {
3009 		if (klip->li_force) {
3010 			/* Mark the device for cleanup. */
3011 			lofi_set_cleanup(lsp);
3012 			mutex_enter(&lsp->ls_vp_lock);
3013 			lsp->ls_vp_closereq = B_TRUE;
3014 			/* Wake up any threads waiting on dkiocstate. */
3015 			cv_broadcast(&lsp->ls_vp_cv);
3016 			while (lsp->ls_vp_iocount > 0)
3017 				cv_wait(&lsp->ls_vp_cv, &lsp->ls_vp_lock);
3018 			mutex_exit(&lsp->ls_vp_lock);
3019 		} else if (klip->li_cleanup) {
3020 			lofi_set_cleanup(lsp);
3021 		} else {
3022 			err = EBUSY;
3023 		}
3024 	} else {
3025 		lofi_free_dev(lsp);
3026 		lofi_destroy(lsp, credp);
3027 	}
3028 
3029 	/* Remove name from devlink cache */
3030 	mutex_enter(&lofi_devlink_cache.ln_lock);
3031 	(void) nvlist_remove_all(lofi_devlink_cache.ln_data, namebuf);
3032 	mutex_exit(&lofi_devlink_cache.ln_lock);
3033 done:
3034 	mutex_exit(&lofi_lock);
3035 	if (err == 0)
3036 		(void) copy_out_lofi_ioctl(klip, ulip, ioctl_flag);
3037 	free_lofi_ioctl(klip);
3038 	return (err);
3039 }
3040 
3041 /*
3042  * get the filename given the minor number, or the minor number given
3043  * the name.
3044  */
3045 /*ARGSUSED*/
3046 static int
3047 lofi_get_info(dev_t dev, struct lofi_ioctl *ulip, int which,
3048     struct cred *credp, int ioctl_flag)
3049 {
3050 	struct lofi_ioctl *klip;
3051 	struct lofi_state *lsp;
3052 	int	error;
3053 
3054 	error = copy_in_lofi_ioctl(ulip, &klip, ioctl_flag);
3055 	if (error != 0)
3056 		return (error);
3057 
3058 	switch (which) {
3059 	case LOFI_GET_FILENAME:
3060 		if (klip->li_id == 0) {
3061 			free_lofi_ioctl(klip);
3062 			return (EINVAL);
3063 		}
3064 
3065 		mutex_enter(&lofi_lock);
3066 		lsp = ddi_get_soft_state(lofi_statep, klip->li_id);
3067 		if (lsp == NULL || lofi_access(lsp) != 0) {
3068 			mutex_exit(&lofi_lock);
3069 			free_lofi_ioctl(klip);
3070 			return (ENXIO);
3071 		}
3072 
3073 		/*
3074 		 * This may fail if, for example, we're trying to look
3075 		 * up a zoned NFS path from the global zone.
3076 		 */
3077 		if (vnodetopath(NULL, lsp->ls_stacked_vp, klip->li_filename,
3078 		    sizeof (klip->li_filename), CRED()) != 0) {
3079 			(void) strlcpy(klip->li_filename, "?",
3080 			    sizeof (klip->li_filename));
3081 		}
3082 
3083 		klip->li_readonly = lsp->ls_readonly;
3084 		klip->li_labeled = lsp->ls_cmlbhandle != NULL;
3085 
3086 		(void) strlcpy(klip->li_algorithm, lsp->ls_comp_algorithm,
3087 		    sizeof (klip->li_algorithm));
3088 		klip->li_crypto_enabled = lsp->ls_crypto_enabled;
3089 		mutex_exit(&lofi_lock);
3090 
3091 		lofi_copy_devpath(klip);
3092 		error = copy_out_lofi_ioctl(klip, ulip, ioctl_flag);
3093 		free_lofi_ioctl(klip);
3094 		return (error);
3095 	case LOFI_GET_MINOR:
3096 		mutex_enter(&lofi_lock);
3097 		error = file_to_lofi(klip->li_filename,
3098 		    klip->li_readonly, &lsp);
3099 		if (error != 0) {
3100 			mutex_exit(&lofi_lock);
3101 			free_lofi_ioctl(klip);
3102 			return (error);
3103 		}
3104 		klip->li_id = LOFI_MINOR2ID(getminor(lsp->ls_dev));
3105 
3106 		klip->li_readonly = lsp->ls_readonly;
3107 		klip->li_labeled = lsp->ls_cmlbhandle != NULL;
3108 		mutex_exit(&lofi_lock);
3109 
3110 		lofi_copy_devpath(klip);
3111 		error = copy_out_lofi_ioctl(klip, ulip, ioctl_flag);
3112 
3113 		free_lofi_ioctl(klip);
3114 		return (error);
3115 	case LOFI_CHECK_COMPRESSED:
3116 		mutex_enter(&lofi_lock);
3117 		error = file_to_lofi(klip->li_filename,
3118 		    klip->li_readonly, &lsp);
3119 		if (error != 0) {
3120 			mutex_exit(&lofi_lock);
3121 			free_lofi_ioctl(klip);
3122 			return (error);
3123 		}
3124 
3125 		klip->li_id = LOFI_MINOR2ID(getminor(lsp->ls_dev));
3126 		(void) strlcpy(klip->li_algorithm, lsp->ls_comp_algorithm,
3127 		    sizeof (klip->li_algorithm));
3128 
3129 		mutex_exit(&lofi_lock);
3130 		error = copy_out_lofi_ioctl(klip, ulip, ioctl_flag);
3131 		free_lofi_ioctl(klip);
3132 		return (error);
3133 	default:
3134 		free_lofi_ioctl(klip);
3135 		return (EINVAL);
3136 	}
3137 }
3138 
3139 static int
3140 uscsi_is_inquiry(intptr_t arg, int flag, union scsi_cdb *cdb,
3141     struct uscsi_cmd *uscmd)
3142 {
3143 	int rval;
3144 
3145 #ifdef	_MULTI_DATAMODEL
3146 	switch (ddi_model_convert_from(flag & FMODELS)) {
3147 	case DDI_MODEL_ILP32: {
3148 		struct uscsi_cmd32 ucmd32;
3149 
3150 		if (ddi_copyin((void *)arg, &ucmd32, sizeof (ucmd32), flag)) {
3151 			rval = EFAULT;
3152 			goto err;
3153 		}
3154 		uscsi_cmd32touscsi_cmd((&ucmd32), uscmd);
3155 		break;
3156 	}
3157 	case DDI_MODEL_NONE:
3158 		if (ddi_copyin((void *)arg, uscmd, sizeof (*uscmd), flag)) {
3159 			rval = EFAULT;
3160 			goto err;
3161 		}
3162 		break;
3163 	default:
3164 		rval = EFAULT;
3165 		goto err;
3166 	}
3167 #else
3168 	if (ddi_copyin((void *)arg, uscmd, sizeof (*uscmd), flag)) {
3169 		rval = EFAULT;
3170 		goto err;
3171 	}
3172 #endif	/* _MULTI_DATAMODEL */
3173 	if (ddi_copyin(uscmd->uscsi_cdb, cdb, uscmd->uscsi_cdblen, flag)) {
3174 		rval = EFAULT;
3175 		goto err;
3176 	}
3177 	if (cdb->scc_cmd == SCMD_INQUIRY) {
3178 		return (0);
3179 	}
3180 err:
3181 	return (rval);
3182 }
3183 
3184 static int
3185 lofi_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *credp,
3186     int *rvalp)
3187 {
3188 	int	error;
3189 	enum dkio_state dkstate;
3190 	struct lofi_state *lsp;
3191 	int	id;
3192 
3193 	id = LOFI_MINOR2ID(getminor(dev));
3194 
3195 	/* lofi ioctls only apply to the master device */
3196 	if (id == 0) {
3197 		struct lofi_ioctl *lip = (struct lofi_ioctl *)arg;
3198 
3199 		/*
3200 		 * the query command only need read-access - i.e., normal
3201 		 * users are allowed to do those on the ctl device as
3202 		 * long as they can open it read-only.
3203 		 */
3204 		switch (cmd) {
3205 		case LOFI_MAP_FILE:
3206 			if ((flag & FWRITE) == 0)
3207 				return (EPERM);
3208 			return (lofi_map_file(dev, lip, 1, rvalp, credp, flag));
3209 		case LOFI_MAP_FILE_MINOR:
3210 			if ((flag & FWRITE) == 0)
3211 				return (EPERM);
3212 			return (lofi_map_file(dev, lip, 0, rvalp, credp, flag));
3213 		case LOFI_UNMAP_FILE:
3214 			if ((flag & FWRITE) == 0)
3215 				return (EPERM);
3216 			return (lofi_unmap_file(lip, 1, credp, flag));
3217 		case LOFI_UNMAP_FILE_MINOR:
3218 			if ((flag & FWRITE) == 0)
3219 				return (EPERM);
3220 			return (lofi_unmap_file(lip, 0, credp, flag));
3221 		case LOFI_GET_FILENAME:
3222 			return (lofi_get_info(dev, lip, LOFI_GET_FILENAME,
3223 			    credp, flag));
3224 		case LOFI_GET_MINOR:
3225 			return (lofi_get_info(dev, lip, LOFI_GET_MINOR,
3226 			    credp, flag));
3227 
3228 		/*
3229 		 * This API made limited sense when this value was fixed
3230 		 * at LOFI_MAX_FILES.  However, its use to iterate
3231 		 * across all possible devices in lofiadm means we don't
3232 		 * want to return L_MAXMIN, but the highest
3233 		 * *allocated* id.
3234 		 */
3235 		case LOFI_GET_MAXMINOR:
3236 			id = 0;
3237 
3238 			mutex_enter(&lofi_lock);
3239 
3240 			for (lsp = list_head(&lofi_list); lsp != NULL;
3241 			    lsp = list_next(&lofi_list, lsp)) {
3242 				int i;
3243 				if (lofi_access(lsp) != 0)
3244 					continue;
3245 
3246 				i = ddi_get_instance(lsp->ls_dip);
3247 				if (i > id)
3248 					id = i;
3249 			}
3250 
3251 			mutex_exit(&lofi_lock);
3252 
3253 			error = ddi_copyout(&id, &lip->li_id,
3254 			    sizeof (id), flag);
3255 			if (error)
3256 				return (EFAULT);
3257 			return (0);
3258 
3259 		case LOFI_CHECK_COMPRESSED:
3260 			return (lofi_get_info(dev, lip, LOFI_CHECK_COMPRESSED,
3261 			    credp, flag));
3262 		default:
3263 			return (EINVAL);
3264 		}
3265 	}
3266 
3267 	mutex_enter(&lofi_lock);
3268 	lsp = ddi_get_soft_state(lofi_statep, id);
3269 	if (lsp == NULL || lsp->ls_cleanup) {
3270 		mutex_exit(&lofi_lock);
3271 		return (ENXIO);
3272 	}
3273 	mutex_exit(&lofi_lock);
3274 
3275 	if (ddi_prop_exists(DDI_DEV_T_ANY, lsp->ls_dip, DDI_PROP_DONTPASS,
3276 	    "labeled") == 1) {
3277 		error = cmlb_ioctl(lsp->ls_cmlbhandle, dev, cmd, arg, flag,
3278 		    credp, rvalp, 0);
3279 		if (error != ENOTTY)
3280 			return (error);
3281 	}
3282 
3283 	/*
3284 	 * We explicitly allow DKIOCSTATE, but all other ioctls should fail with
3285 	 * EIO as if the device was no longer present.
3286 	 */
3287 	if (lsp->ls_vp == NULL && cmd != DKIOCSTATE)
3288 		return (EIO);
3289 
3290 	/* these are for faking out utilities like newfs */
3291 	switch (cmd) {
3292 	case DKIOCGMEDIAINFO:
3293 	case DKIOCGMEDIAINFOEXT: {
3294 		struct dk_minfo_ext media_info;
3295 		int shift = lsp->ls_lbshift;
3296 		int size;
3297 
3298 		if (cmd == DKIOCGMEDIAINFOEXT) {
3299 			media_info.dki_pbsize = 1U << lsp->ls_pbshift;
3300 			size = sizeof (struct dk_minfo_ext);
3301 		} else {
3302 			size = sizeof (struct dk_minfo);
3303 		}
3304 
3305 		media_info.dki_media_type = DK_FIXED_DISK;
3306 		media_info.dki_lbsize = 1U << shift;
3307 		media_info.dki_capacity =
3308 		    (lsp->ls_vp_size - lsp->ls_crypto_offset) >> shift;
3309 
3310 		if (ddi_copyout(&media_info, (void *)arg, size, flag))
3311 			return (EFAULT);
3312 		return (0);
3313 	}
3314 	case DKIOCREMOVABLE: {
3315 		int i = 0;
3316 		if (ddi_copyout(&i, (caddr_t)arg, sizeof (int), flag))
3317 			return (EFAULT);
3318 		return (0);
3319 	}
3320 
3321 	case DKIOCGVTOC: {
3322 		struct vtoc vt;
3323 		fake_disk_vtoc(lsp, &vt);
3324 
3325 		switch (ddi_model_convert_from(flag & FMODELS)) {
3326 		case DDI_MODEL_ILP32: {
3327 			struct vtoc32 vtoc32;
3328 
3329 			vtoctovtoc32(vt, vtoc32);
3330 			if (ddi_copyout(&vtoc32, (void *)arg,
3331 			    sizeof (struct vtoc32), flag))
3332 				return (EFAULT);
3333 			break;
3334 			}
3335 
3336 		case DDI_MODEL_NONE:
3337 			if (ddi_copyout(&vt, (void *)arg,
3338 			    sizeof (struct vtoc), flag))
3339 				return (EFAULT);
3340 			break;
3341 		}
3342 		return (0);
3343 	}
3344 	case DKIOCINFO: {
3345 		struct dk_cinfo ci;
3346 		fake_disk_info(dev, &ci);
3347 		if (ddi_copyout(&ci, (void *)arg, sizeof (ci), flag))
3348 			return (EFAULT);
3349 		return (0);
3350 	}
3351 	case DKIOCG_VIRTGEOM:
3352 	case DKIOCG_PHYGEOM:
3353 	case DKIOCGGEOM:
3354 		error = ddi_copyout(&lsp->ls_dkg, (void *)arg,
3355 		    sizeof (struct dk_geom), flag);
3356 		if (error)
3357 			return (EFAULT);
3358 		return (0);
3359 	case DKIOCSTATE:
3360 		/*
3361 		 * Normally, lofi devices are always in the INSERTED state.  If
3362 		 * a device is forcefully unmapped, then the device transitions
3363 		 * to the DKIO_DEV_GONE state.
3364 		 */
3365 		if (ddi_copyin((void *)arg, &dkstate, sizeof (dkstate),
3366 		    flag) != 0)
3367 			return (EFAULT);
3368 
3369 		mutex_enter(&lsp->ls_vp_lock);
3370 		while (((dkstate == DKIO_INSERTED && lsp->ls_vp != NULL) ||
3371 		    (dkstate == DKIO_DEV_GONE && lsp->ls_vp == NULL)) &&
3372 		    !lsp->ls_cleanup) {
3373 			/*
3374 			 * By virtue of having the device open, we know that
3375 			 * 'lsp' will remain valid when we return.
3376 			 */
3377 			if (!cv_wait_sig(&lsp->ls_vp_cv, &lsp->ls_vp_lock)) {
3378 				mutex_exit(&lsp->ls_vp_lock);
3379 				return (EINTR);
3380 			}
3381 		}
3382 
3383 		dkstate = (!lsp->ls_cleanup && lsp->ls_vp != NULL ?
3384 		    DKIO_INSERTED : DKIO_DEV_GONE);
3385 		mutex_exit(&lsp->ls_vp_lock);
3386 
3387 		if (ddi_copyout(&dkstate, (void *)arg,
3388 		    sizeof (dkstate), flag) != 0)
3389 			return (EFAULT);
3390 		return (0);
3391 	case USCSICMD: {
3392 		struct uscsi_cmd uscmd;
3393 		union scsi_cdb cdb;
3394 
3395 		if (uscsi_is_inquiry(arg, flag, &cdb, &uscmd) == 0) {
3396 			struct scsi_inquiry inq = {0};
3397 
3398 			lofi_create_inquiry(lsp, &inq);
3399 			if (ddi_copyout(&inq, uscmd.uscsi_bufaddr,
3400 			    uscmd.uscsi_buflen, flag) != 0)
3401 				return (EFAULT);
3402 			return (0);
3403 		} else if (cdb.scc_cmd == SCMD_READ_CAPACITY) {
3404 			struct scsi_capacity capacity;
3405 
3406 			capacity.capacity =
3407 			    BE_32((lsp->ls_vp_size - lsp->ls_crypto_offset) >>
3408 			    lsp->ls_lbshift);
3409 			capacity.lbasize = BE_32(1 << lsp->ls_lbshift);
3410 			if (ddi_copyout(&capacity, uscmd.uscsi_bufaddr,
3411 			    uscmd.uscsi_buflen, flag) != 0)
3412 				return (EFAULT);
3413 			return (0);
3414 		}
3415 
3416 		uscmd.uscsi_rqstatus = 0xff;
3417 #ifdef	_MULTI_DATAMODEL
3418 		switch (ddi_model_convert_from(flag & FMODELS)) {
3419 		case DDI_MODEL_ILP32: {
3420 			struct uscsi_cmd32 ucmd32;
3421 			uscsi_cmdtouscsi_cmd32((&uscmd), (&ucmd32));
3422 			if (ddi_copyout(&ucmd32, (void *)arg, sizeof (ucmd32),
3423 			    flag) != 0)
3424 				return (EFAULT);
3425 			break;
3426 		}
3427 		case DDI_MODEL_NONE:
3428 			if (ddi_copyout(&uscmd, (void *)arg, sizeof (uscmd),
3429 			    flag) != 0)
3430 				return (EFAULT);
3431 			break;
3432 		default:
3433 			return (EFAULT);
3434 		}
3435 #else
3436 		if (ddi_copyout(&uscmd, (void *)arg, sizeof (uscmd), flag) != 0)
3437 			return (EFAULT);
3438 #endif	/* _MULTI_DATAMODEL */
3439 		return (0);
3440 	}
3441 	default:
3442 #ifdef DEBUG
3443 		cmn_err(CE_WARN, "lofi_ioctl: %d is not implemented\n", cmd);
3444 #endif	/* DEBUG */
3445 		return (ENOTTY);
3446 	}
3447 }
3448 
3449 static int
3450 lofi_prop_op(dev_t dev, dev_info_t *dip, ddi_prop_op_t prop_op, int mod_flags,
3451     char *name, caddr_t valuep, int *lengthp)
3452 {
3453 	struct lofi_state *lsp;
3454 	int rc;
3455 
3456 	lsp = ddi_get_soft_state(lofi_statep, ddi_get_instance(dip));
3457 	if (lsp == NULL) {
3458 		return (ddi_prop_op(dev, dip, prop_op, mod_flags,
3459 		    name, valuep, lengthp));
3460 	}
3461 
3462 	rc = cmlb_prop_op(lsp->ls_cmlbhandle, dev, dip, prop_op, mod_flags,
3463 	    name, valuep, lengthp, LOFI_PART(getminor(dev)), NULL);
3464 	if (rc == DDI_PROP_SUCCESS)
3465 		return (rc);
3466 
3467 	return (ddi_prop_op(DDI_DEV_T_ANY, dip, prop_op, mod_flags,
3468 	    name, valuep, lengthp));
3469 }
3470 
3471 static struct cb_ops lofi_cb_ops = {
3472 	lofi_open,		/* open */
3473 	lofi_close,		/* close */
3474 	lofi_strategy,		/* strategy */
3475 	nodev,			/* print */
3476 	nodev,			/* dump */
3477 	lofi_read,		/* read */
3478 	lofi_write,		/* write */
3479 	lofi_ioctl,		/* ioctl */
3480 	nodev,			/* devmap */
3481 	nodev,			/* mmap */
3482 	nodev,			/* segmap */
3483 	nochpoll,		/* poll */
3484 	lofi_prop_op,		/* prop_op */
3485 	0,			/* streamtab  */
3486 	D_64BIT | D_NEW | D_MP,	/* Driver compatibility flag */
3487 	CB_REV,
3488 	lofi_aread,
3489 	lofi_awrite
3490 };
3491 
3492 static struct dev_ops lofi_ops = {
3493 	DEVO_REV,		/* devo_rev, */
3494 	0,			/* refcnt  */
3495 	lofi_info,		/* info */
3496 	nulldev,		/* identify */
3497 	nulldev,		/* probe */
3498 	lofi_attach,		/* attach */
3499 	lofi_detach,		/* detach */
3500 	nodev,			/* reset */
3501 	&lofi_cb_ops,		/* driver operations */
3502 	NULL,			/* no bus operations */
3503 	NULL,			/* power */
3504 	ddi_quiesce_not_needed,	/* quiesce */
3505 };
3506 
3507 static struct modldrv modldrv = {
3508 	&mod_driverops,
3509 	"loopback file driver",
3510 	&lofi_ops,
3511 };
3512 
3513 static struct modlinkage modlinkage = {
3514 	MODREV_1,
3515 	&modldrv,
3516 	NULL
3517 };
3518 
3519 int
3520 _init(void)
3521 {
3522 	int error;
3523 
3524 	list_create(&lofi_list, sizeof (struct lofi_state),
3525 	    offsetof(struct lofi_state, ls_list));
3526 
3527 	error = ddi_soft_state_init((void **)&lofi_statep,
3528 	    sizeof (struct lofi_state), 0);
3529 	if (error) {
3530 		list_destroy(&lofi_list);
3531 		return (error);
3532 	}
3533 
3534 	/*
3535 	 * The minor number is stored as id << LOFI_CMLB_SHIFT as
3536 	 * we need to reserve space for cmlb minor numbers.
3537 	 * This will leave out 4096 id values on 32bit kernel, which should
3538 	 * still suffice.
3539 	 */
3540 	lofi_id = id_space_create("lofi_id", 1,
3541 	    (1 << (L_BITSMINOR - LOFI_CMLB_SHIFT)));
3542 
3543 	if (lofi_id == NULL) {
3544 		ddi_soft_state_fini((void **)&lofi_statep);
3545 		list_destroy(&lofi_list);
3546 		return (DDI_FAILURE);
3547 	}
3548 
3549 	mutex_init(&lofi_lock, NULL, MUTEX_DRIVER, NULL);
3550 
3551 	error = mod_install(&modlinkage);
3552 
3553 	if (error) {
3554 		id_space_destroy(lofi_id);
3555 		mutex_destroy(&lofi_lock);
3556 		ddi_soft_state_fini((void **)&lofi_statep);
3557 		list_destroy(&lofi_list);
3558 	}
3559 
3560 	return (error);
3561 }
3562 
3563 int
3564 _fini(void)
3565 {
3566 	int	error;
3567 
3568 	mutex_enter(&lofi_lock);
3569 
3570 	if (!list_is_empty(&lofi_list)) {
3571 		mutex_exit(&lofi_lock);
3572 		return (EBUSY);
3573 	}
3574 
3575 	mutex_exit(&lofi_lock);
3576 
3577 	error = mod_remove(&modlinkage);
3578 	if (error)
3579 		return (error);
3580 
3581 	mutex_destroy(&lofi_lock);
3582 	id_space_destroy(lofi_id);
3583 	ddi_soft_state_fini((void **)&lofi_statep);
3584 	list_destroy(&lofi_list);
3585 
3586 	return (error);
3587 }
3588 
3589 int
3590 _info(struct modinfo *modinfop)
3591 {
3592 	return (mod_info(&modlinkage, modinfop));
3593 }
3594