xref: /netbsd-src/sys/dev/vnd.c (revision c0179c282a5968435315a82f4128c61372c68fc3)
1 /*	$NetBSD: vnd.c,v 1.160 2006/11/16 01:32:45 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Copyright (c) 1990, 1993
41  *	The Regents of the University of California.  All rights reserved.
42  *
43  * This code is derived from software contributed to Berkeley by
44  * the Systems Programming Group of the University of Utah Computer
45  * Science Department.
46  *
47  * Redistribution and use in source and binary forms, with or without
48  * modification, are permitted provided that the following conditions
49  * are met:
50  * 1. Redistributions of source code must retain the above copyright
51  *    notice, this list of conditions and the following disclaimer.
52  * 2. Redistributions in binary form must reproduce the above copyright
53  *    notice, this list of conditions and the following disclaimer in the
54  *    documentation and/or other materials provided with the distribution.
55  * 3. Neither the name of the University nor the names of its contributors
56  *    may be used to endorse or promote products derived from this software
57  *    without specific prior written permission.
58  *
59  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69  * SUCH DAMAGE.
70  *
71  * from: Utah $Hdr: vn.c 1.13 94/04/02$
72  *
73  *	@(#)vn.c	8.9 (Berkeley) 5/14/95
74  */
75 
76 /*
77  * Copyright (c) 1988 University of Utah.
78  *
79  * This code is derived from software contributed to Berkeley by
80  * the Systems Programming Group of the University of Utah Computer
81  * Science Department.
82  *
83  * Redistribution and use in source and binary forms, with or without
84  * modification, are permitted provided that the following conditions
85  * are met:
86  * 1. Redistributions of source code must retain the above copyright
87  *    notice, this list of conditions and the following disclaimer.
88  * 2. Redistributions in binary form must reproduce the above copyright
89  *    notice, this list of conditions and the following disclaimer in the
90  *    documentation and/or other materials provided with the distribution.
91  * 3. All advertising materials mentioning features or use of this software
92  *    must display the following acknowledgement:
93  *	This product includes software developed by the University of
94  *	California, Berkeley and its contributors.
95  * 4. Neither the name of the University nor the names of its contributors
96  *    may be used to endorse or promote products derived from this software
97  *    without specific prior written permission.
98  *
99  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
100  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
101  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
102  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
103  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
104  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
105  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
106  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
107  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
108  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
109  * SUCH DAMAGE.
110  *
111  * from: Utah $Hdr: vn.c 1.13 94/04/02$
112  *
113  *	@(#)vn.c	8.9 (Berkeley) 5/14/95
114  */
115 
116 /*
117  * Vnode disk driver.
118  *
119  * Block/character interface to a vnode.  Allows one to treat a file
120  * as a disk (e.g. build a filesystem in it, mount it, etc.).
121  *
122  * NOTE 1: If the vnode supports the VOP_BMAP and VOP_STRATEGY operations,
123  * this uses them to avoid distorting the local buffer cache.  If those
124  * block-level operations are not available, this falls back to the regular
125  * read and write calls.  Using these may distort the cache in some cases
126  * but better have the driver working than preventing it to work on file
127  * systems where the block-level operations are not implemented for
128  * whatever reason.
129  *
130  * NOTE 2: There is a security issue involved with this driver.
131  * Once mounted all access to the contents of the "mapped" file via
132  * the special file is controlled by the permissions on the special
133  * file, the protection of the mapped file is ignored (effectively,
134  * by using root credentials in all transactions).
135  *
136  * NOTE 3: Doesn't interact with leases, should it?
137  */
138 
139 #include <sys/cdefs.h>
140 __KERNEL_RCSID(0, "$NetBSD: vnd.c,v 1.160 2006/11/16 01:32:45 christos Exp $");
141 
142 #if defined(_KERNEL_OPT)
143 #include "fs_nfs.h"
144 #include "opt_vnd.h"
145 #endif
146 
147 #include <sys/param.h>
148 #include <sys/systm.h>
149 #include <sys/namei.h>
150 #include <sys/proc.h>
151 #include <sys/kthread.h>
152 #include <sys/errno.h>
153 #include <sys/buf.h>
154 #include <sys/bufq.h>
155 #include <sys/malloc.h>
156 #include <sys/ioctl.h>
157 #include <sys/disklabel.h>
158 #include <sys/device.h>
159 #include <sys/disk.h>
160 #include <sys/stat.h>
161 #include <sys/mount.h>
162 #include <sys/vnode.h>
163 #include <sys/file.h>
164 #include <sys/uio.h>
165 #include <sys/conf.h>
166 #include <sys/kauth.h>
167 
168 #include <net/zlib.h>
169 
170 #include <miscfs/genfs/genfs.h>
171 #include <miscfs/specfs/specdev.h>
172 
173 #include <dev/vndvar.h>
174 
175 #if defined(VNDDEBUG) && !defined(DEBUG)
176 #define DEBUG
177 #endif
178 
179 #ifdef DEBUG
180 int dovndcluster = 1;
181 #define VDB_FOLLOW	0x01
182 #define VDB_INIT	0x02
183 #define VDB_IO		0x04
184 #define VDB_LABEL	0x08
185 int vnddebug = 0x00;
186 #endif
187 
188 #define vndunit(x)	DISKUNIT(x)
189 
190 struct vndxfer {
191 	struct buf vx_buf;
192 	struct vnd_softc *vx_vnd;
193 };
194 #define	VND_BUFTOXFER(bp)	((struct vndxfer *)(void *)bp)
195 
196 #define VND_GETXFER(vnd)	pool_get(&(vnd)->sc_vxpool, PR_WAITOK)
197 #define VND_PUTXFER(vnd, vx)	pool_put(&(vnd)->sc_vxpool, (vx))
198 
199 #define VNDLABELDEV(dev) \
200     (MAKEDISKDEV(major((dev)), vndunit((dev)), RAW_PART))
201 
202 /* called by main() at boot time (XXX: and the LKM driver) */
203 void	vndattach(int);
204 
205 static void	vndclear(struct vnd_softc *, int);
206 static int	vndsetcred(struct vnd_softc *, kauth_cred_t);
207 static void	vndthrottle(struct vnd_softc *, struct vnode *);
208 static void	vndiodone(struct buf *);
209 #if 0
210 static void	vndshutdown(void);
211 #endif
212 
213 static void	vndgetdefaultlabel(struct vnd_softc *, struct disklabel *);
214 static void	vndgetdisklabel(dev_t, struct vnd_softc *);
215 
216 static int	vndlock(struct vnd_softc *);
217 static void	vndunlock(struct vnd_softc *);
218 #ifdef VND_COMPRESSION
219 static void	compstrategy(struct buf *, off_t);
220 static void	*vnd_alloc(void *, u_int, u_int);
221 static void	vnd_free(void *, void *);
222 #endif /* VND_COMPRESSION */
223 
224 static void	vndthread(void *);
225 static boolean_t vnode_has_op(const struct vnode *, int);
226 static void	handle_with_rdwr(struct vnd_softc *, const struct buf *,
227 		    struct buf *);
228 static void	handle_with_strategy(struct vnd_softc *, const struct buf *,
229 		    struct buf *);
230 
231 static dev_type_open(vndopen);
232 static dev_type_close(vndclose);
233 static dev_type_read(vndread);
234 static dev_type_write(vndwrite);
235 static dev_type_ioctl(vndioctl);
236 static dev_type_strategy(vndstrategy);
237 static dev_type_dump(vnddump);
238 static dev_type_size(vndsize);
239 
240 const struct bdevsw vnd_bdevsw = {
241 	vndopen, vndclose, vndstrategy, vndioctl, vnddump, vndsize, D_DISK
242 };
243 
244 const struct cdevsw vnd_cdevsw = {
245 	vndopen, vndclose, vndread, vndwrite, vndioctl,
246 	nostop, notty, nopoll, nommap, nokqfilter, D_DISK
247 };
248 
249 static int	vnd_match(struct device *, struct cfdata *, void *);
250 static void	vnd_attach(struct device *, struct device *, void *);
251 static int	vnd_detach(struct device *, int);
252 
253 CFATTACH_DECL(vnd, sizeof(struct vnd_softc),
254     vnd_match, vnd_attach, vnd_detach, NULL);
255 extern struct cfdriver vnd_cd;
256 
257 static struct vnd_softc	*vnd_spawn(int);
258 int	vnd_destroy(struct device *);
259 
260 void
261 vndattach(int num)
262 {
263 	int error;
264 
265 	error = config_cfattach_attach(vnd_cd.cd_name, &vnd_ca);
266 	if (error)
267 		aprint_error("%s: unable to register cfattach\n",
268 		    vnd_cd.cd_name);
269 }
270 
271 static int
272 vnd_match(struct device *self, struct cfdata *cfdata,
273     void *aux)
274 {
275 	return 1;
276 }
277 
278 static void
279 vnd_attach(struct device *parent, struct device *self,
280     void *aux)
281 {
282 	struct vnd_softc *sc = (struct vnd_softc *)self;
283 
284 	sc->sc_comp_offsets = NULL;
285 	sc->sc_comp_buff = NULL;
286 	sc->sc_comp_decombuf = NULL;
287 	bufq_alloc(&sc->sc_tab, "disksort", BUFQ_SORT_RAWBLOCK);
288 	pseudo_disk_init(&sc->sc_dkdev);
289 }
290 
291 static int
292 vnd_detach(struct device *self, int flags)
293 {
294 	struct vnd_softc *sc = (struct vnd_softc *)self;
295 	if (sc->sc_flags & VNF_INITED)
296 		return EBUSY;
297 
298 	bufq_free(sc->sc_tab);
299 
300 	return 0;
301 }
302 
303 static struct vnd_softc *
304 vnd_spawn(int unit)
305 {
306 	struct cfdata *cf;
307 
308 	cf = malloc(sizeof(*cf), M_DEVBUF, M_WAITOK);
309 	cf->cf_name = vnd_cd.cd_name;
310 	cf->cf_atname = vnd_cd.cd_name;
311 	cf->cf_unit = unit;
312 	cf->cf_fstate = FSTATE_STAR;
313 
314 	return (struct vnd_softc *)config_attach_pseudo(cf);
315 }
316 
317 int
318 vnd_destroy(struct device *dev)
319 {
320 	int error;
321 	struct cfdata *cf;
322 
323 	cf = device_cfdata(dev);
324 	error = config_detach(dev, DETACH_QUIET);
325 	if (error)
326 		return error;
327 	free(cf, M_DEVBUF);
328 	return 0;
329 }
330 
331 static int
332 vndopen(dev_t dev, int flags, int mode, struct lwp *l)
333 {
334 	int unit = vndunit(dev);
335 	struct vnd_softc *sc;
336 	int error = 0, part, pmask;
337 	struct disklabel *lp;
338 
339 #ifdef DEBUG
340 	if (vnddebug & VDB_FOLLOW)
341 		printf("vndopen(0x%x, 0x%x, 0x%x, %p)\n", dev, flags, mode, l);
342 #endif
343 	sc = device_lookup(&vnd_cd, unit);
344 	if (sc == NULL) {
345 		sc = vnd_spawn(unit);
346 		if (sc == NULL)
347 			return ENOMEM;
348 	}
349 
350 	if ((error = vndlock(sc)) != 0)
351 		return (error);
352 
353 	lp = sc->sc_dkdev.dk_label;
354 
355 	part = DISKPART(dev);
356 	pmask = (1 << part);
357 
358 	/*
359 	 * If we're initialized, check to see if there are any other
360 	 * open partitions.  If not, then it's safe to update the
361 	 * in-core disklabel.  Only read the disklabel if it is
362 	 * not already valid.
363 	 */
364 	if ((sc->sc_flags & (VNF_INITED|VNF_VLABEL)) == VNF_INITED &&
365 	    sc->sc_dkdev.dk_openmask == 0)
366 		vndgetdisklabel(dev, sc);
367 
368 	/* Check that the partitions exists. */
369 	if (part != RAW_PART) {
370 		if (((sc->sc_flags & VNF_INITED) == 0) ||
371 		    ((part >= lp->d_npartitions) ||
372 		     (lp->d_partitions[part].p_fstype == FS_UNUSED))) {
373 			error = ENXIO;
374 			goto done;
375 		}
376 	}
377 
378 	/* Prevent our unit from being unconfigured while open. */
379 	switch (mode) {
380 	case S_IFCHR:
381 		sc->sc_dkdev.dk_copenmask |= pmask;
382 		break;
383 
384 	case S_IFBLK:
385 		sc->sc_dkdev.dk_bopenmask |= pmask;
386 		break;
387 	}
388 	sc->sc_dkdev.dk_openmask =
389 	    sc->sc_dkdev.dk_copenmask | sc->sc_dkdev.dk_bopenmask;
390 
391  done:
392 	vndunlock(sc);
393 	return (error);
394 }
395 
396 static int
397 vndclose(dev_t dev, int flags, int mode, struct lwp *l)
398 {
399 	int unit = vndunit(dev);
400 	struct vnd_softc *sc;
401 	int error = 0, part;
402 
403 #ifdef DEBUG
404 	if (vnddebug & VDB_FOLLOW)
405 		printf("vndclose(0x%x, 0x%x, 0x%x, %p)\n", dev, flags, mode, l);
406 #endif
407 	sc = device_lookup(&vnd_cd, unit);
408 	if (sc == NULL)
409 		return ENXIO;
410 
411 	if ((error = vndlock(sc)) != 0)
412 		return (error);
413 
414 	part = DISKPART(dev);
415 
416 	/* ...that much closer to allowing unconfiguration... */
417 	switch (mode) {
418 	case S_IFCHR:
419 		sc->sc_dkdev.dk_copenmask &= ~(1 << part);
420 		break;
421 
422 	case S_IFBLK:
423 		sc->sc_dkdev.dk_bopenmask &= ~(1 << part);
424 		break;
425 	}
426 	sc->sc_dkdev.dk_openmask =
427 	    sc->sc_dkdev.dk_copenmask | sc->sc_dkdev.dk_bopenmask;
428 
429 	vndunlock(sc);
430 
431 	if ((sc->sc_flags & VNF_INITED) == 0) {
432 		if ((error = vnd_destroy((struct device *)sc)) != 0) {
433 			aprint_error("%s: unable to detach instance\n",
434 			    sc->sc_dev.dv_xname);
435 			return error;
436 		}
437 	}
438 
439 	return (0);
440 }
441 
442 /*
443  * Queue the request, and wakeup the kernel thread to handle it.
444  */
445 static void
446 vndstrategy(struct buf *bp)
447 {
448 	int unit = vndunit(bp->b_dev);
449 	struct vnd_softc *vnd =
450 	    (struct vnd_softc *)device_lookup(&vnd_cd, unit);
451 	struct disklabel *lp = vnd->sc_dkdev.dk_label;
452 	daddr_t blkno;
453 	int s = splbio();
454 
455 	bp->b_resid = bp->b_bcount;
456 
457 	if ((vnd->sc_flags & VNF_INITED) == 0) {
458 		bp->b_error = ENXIO;
459 		bp->b_flags |= B_ERROR;
460 		goto done;
461 	}
462 
463 	/*
464 	 * The transfer must be a whole number of blocks.
465 	 */
466 	if ((bp->b_bcount % lp->d_secsize) != 0) {
467 		bp->b_error = EINVAL;
468 		bp->b_flags |= B_ERROR;
469 		goto done;
470 	}
471 
472 	/*
473 	 * check if we're read-only.
474 	 */
475 	if ((vnd->sc_flags & VNF_READONLY) && !(bp->b_flags & B_READ)) {
476 		bp->b_error = EACCES;
477 		bp->b_flags |= B_ERROR;
478 		goto done;
479 	}
480 
481 	/*
482 	 * Do bounds checking and adjust transfer.  If there's an error,
483 	 * the bounds check will flag that for us.
484 	 */
485 	if (DISKPART(bp->b_dev) == RAW_PART) {
486 		if (bounds_check_with_mediasize(bp, DEV_BSIZE,
487 		    vnd->sc_size) <= 0)
488 			goto done;
489 	} else {
490 		if (bounds_check_with_label(&vnd->sc_dkdev,
491 		    bp, vnd->sc_flags & (VNF_WLABEL|VNF_LABELLING)) <= 0)
492 			goto done;
493 	}
494 
495 	/* If it's a nil transfer, wake up the top half now. */
496 	if (bp->b_bcount == 0)
497 		goto done;
498 
499 	/*
500 	 * Put the block number in terms of the logical blocksize
501 	 * of the "device".
502 	 */
503 
504 	blkno = bp->b_blkno / (lp->d_secsize / DEV_BSIZE);
505 
506 	/*
507 	 * Translate the partition-relative block number to an absolute.
508 	 */
509 	if (DISKPART(bp->b_dev) != RAW_PART) {
510 		struct partition *pp;
511 
512 		pp = &vnd->sc_dkdev.dk_label->d_partitions[
513 		    DISKPART(bp->b_dev)];
514 		blkno += pp->p_offset;
515 	}
516 	bp->b_rawblkno = blkno;
517 
518 #ifdef DEBUG
519 	if (vnddebug & VDB_FOLLOW)
520 		printf("vndstrategy(%p): unit %d\n", bp, unit);
521 #endif
522 	BUFQ_PUT(vnd->sc_tab, bp);
523 	wakeup(&vnd->sc_tab);
524 	splx(s);
525 	return;
526 done:
527 	biodone(bp);
528 	splx(s);
529 }
530 
531 static void
532 vndthread(void *arg)
533 {
534 	struct vnd_softc *vnd = arg;
535 	boolean_t usestrategy;
536 	int s;
537 
538 	/* Determine whether we can use VOP_BMAP and VOP_STRATEGY to
539 	 * directly access the backing vnode.  If we can, use these two
540 	 * operations to avoid messing with the local buffer cache.
541 	 * Otherwise fall back to regular VOP_READ/VOP_WRITE operations
542 	 * which are guaranteed to work with any file system. */
543 	usestrategy = vnode_has_op(vnd->sc_vp, VOFFSET(vop_bmap)) &&
544 	    vnode_has_op(vnd->sc_vp, VOFFSET(vop_strategy));
545 
546 #ifdef DEBUG
547 	if (vnddebug & VDB_INIT)
548 		printf("vndthread: vp %p, %s\n", vnd->sc_vp,
549 		    usestrategy ?
550 		    "using bmap/strategy operations" :
551 		    "using read/write operations");
552 #endif
553 
554 	s = splbio();
555 	vnd->sc_flags |= VNF_KTHREAD;
556 	wakeup(&vnd->sc_kthread);
557 
558 	/*
559 	 * Dequeue requests and serve them depending on the available
560 	 * vnode operations.
561 	 */
562 	while ((vnd->sc_flags & VNF_VUNCONF) == 0) {
563 		struct vndxfer *vnx;
564 		int flags;
565 		struct buf *obp;
566 		struct buf *bp;
567 
568 		obp = BUFQ_GET(vnd->sc_tab);
569 		if (obp == NULL) {
570 			tsleep(&vnd->sc_tab, PRIBIO, "vndbp", 0);
571 			continue;
572 		};
573 		splx(s);
574 		flags = obp->b_flags;
575 #ifdef DEBUG
576 		if (vnddebug & VDB_FOLLOW)
577 			printf("vndthread(%p\n", obp);
578 #endif
579 
580 		if (vnd->sc_vp->v_mount == NULL) {
581 			obp->b_error = ENXIO;
582 			obp->b_flags |= B_ERROR;
583 			goto done;
584 		}
585 #ifdef VND_COMPRESSION
586 		/* handle a compressed read */
587 		if ((flags & B_READ) != 0 && (vnd->sc_flags & VNF_COMP)) {
588 			off_t bn;
589 
590 			/* Convert to a byte offset within the file. */
591 			bn = obp->b_rawblkno *
592 			    vnd->sc_dkdev.dk_label->d_secsize;
593 
594 			compstrategy(obp, bn);
595 			goto done;
596 		}
597 #endif /* VND_COMPRESSION */
598 
599 		/*
600 		 * Allocate a header for this transfer and link it to the
601 		 * buffer
602 		 */
603 		s = splbio();
604 		vnx = VND_GETXFER(vnd);
605 		splx(s);
606 		vnx->vx_vnd = vnd;
607 
608 		s = splbio();
609 		while (vnd->sc_active >= vnd->sc_maxactive) {
610 			tsleep(&vnd->sc_tab, PRIBIO, "vndac", 0);
611 		}
612 		vnd->sc_active++;
613 		splx(s);
614 
615 		/* Instrumentation. */
616 		disk_busy(&vnd->sc_dkdev);
617 
618 		bp = &vnx->vx_buf;
619 		BUF_INIT(bp);
620 		bp->b_flags = (obp->b_flags & B_READ) | B_CALL;
621 		bp->b_iodone = vndiodone;
622 		bp->b_private = obp;
623 		bp->b_vp = vnd->sc_vp;
624 		bp->b_data = obp->b_data;
625 		bp->b_bcount = bp->b_resid = obp->b_bcount;
626 		BIO_COPYPRIO(bp, obp);
627 
628 		/* Handle the request using the appropriate operations. */
629 		if (usestrategy)
630 			handle_with_strategy(vnd, obp, bp);
631 		else
632 			handle_with_rdwr(vnd, obp, bp);
633 
634 		s = splbio();
635 		continue;
636 
637 done:
638 		biodone(obp);
639 		s = splbio();
640 	}
641 
642 	vnd->sc_flags &= (~VNF_KTHREAD | VNF_VUNCONF);
643 	wakeup(&vnd->sc_kthread);
644 	splx(s);
645 	kthread_exit(0);
646 }
647 
648 /*
649  * Checks if the given vnode supports the requested operation.
650  * The operation is specified the offset returned by VOFFSET.
651  *
652  * XXX The test below used to determine this is quite fragile
653  * because it relies on the file system to use genfs to specify
654  * unimplemented operations.  There might be another way to do
655  * it more cleanly.
656  */
657 static boolean_t
658 vnode_has_op(const struct vnode *vp, int opoffset)
659 {
660 	int (*defaultp)(void *);
661 	int (*opp)(void *);
662 
663 	defaultp = vp->v_op[VOFFSET(vop_default)];
664 	opp = vp->v_op[opoffset];
665 
666 	return opp != defaultp && opp != genfs_eopnotsupp &&
667 	    opp != genfs_badop && opp != genfs_nullop;
668 }
669 
670 /*
671  * Handes the read/write request given in 'bp' using the vnode's VOP_READ
672  * and VOP_WRITE operations.
673  *
674  * 'obp' is a pointer to the original request fed to the vnd device.
675  */
676 static void
677 handle_with_rdwr(struct vnd_softc *vnd, const struct buf *obp, struct buf *bp)
678 {
679 	boolean_t doread;
680 	off_t offset;
681 	size_t resid;
682 	struct vnode *vp;
683 
684 	doread = bp->b_flags & B_READ;
685 	offset = obp->b_rawblkno * vnd->sc_dkdev.dk_label->d_secsize;
686 	vp = vnd->sc_vp;
687 
688 #if defined(DEBUG)
689 	if (vnddebug & VDB_IO)
690 		printf("vnd (rdwr): vp %p, %s, rawblkno 0x%" PRIx64
691 		    ", secsize %d, offset %" PRIu64
692 		    ", bcount %d, resid %d\n",
693 		    vp, doread ? "read" : "write", obp->b_rawblkno,
694 		    vnd->sc_dkdev.dk_label->d_secsize, offset,
695 		    bp->b_bcount, bp->b_resid);
696 #endif
697 
698 	/* Issue the read or write operation. */
699 	bp->b_error =
700 	    vn_rdwr(doread ? UIO_READ : UIO_WRITE,
701 	    vp, bp->b_data, bp->b_bcount, offset,
702 	    UIO_SYSSPACE, 0, vnd->sc_cred, &resid, NULL);
703 	bp->b_resid = resid;
704 	if (bp->b_error != 0)
705 		bp->b_flags |= B_ERROR;
706 	else
707 		KASSERT(!(bp->b_flags & B_ERROR));
708 
709 	/* We need to increase the number of outputs on the vnode if
710 	 * there was any write to it. */
711 	if (!doread)
712 		V_INCR_NUMOUTPUT(vp);
713 
714 	biodone(bp);
715 }
716 
717 /*
718  * Handes the read/write request given in 'bp' using the vnode's VOP_BMAP
719  * and VOP_STRATEGY operations.
720  *
721  * 'obp' is a pointer to the original request fed to the vnd device.
722  */
723 static void
724 handle_with_strategy(struct vnd_softc *vnd, const struct buf *obp,
725     struct buf *bp)
726 {
727 	int bsize, error, flags, skipped;
728 	size_t resid, sz;
729 	off_t bn, offset;
730 	struct mount *mp;
731 
732 	flags = obp->b_flags;
733 
734 	mp = NULL;
735 	if (!(flags & B_READ)) {
736 		int s;
737 
738 		s = splbio();
739 		V_INCR_NUMOUTPUT(bp->b_vp);
740 		splx(s);
741 
742 		vn_start_write(vnd->sc_vp, &mp, V_WAIT);
743 		KASSERT(mp != NULL);
744 	}
745 
746 	/* convert to a byte offset within the file. */
747 	bn = obp->b_rawblkno * vnd->sc_dkdev.dk_label->d_secsize;
748 
749 	bsize = vnd->sc_vp->v_mount->mnt_stat.f_iosize;
750 	skipped = 0;
751 
752 	/*
753 	 * Break the request into bsize pieces and feed them
754 	 * sequentially using VOP_BMAP/VOP_STRATEGY.
755 	 * We do it this way to keep from flooding NFS servers if we
756 	 * are connected to an NFS file.  This places the burden on
757 	 * the client rather than the server.
758 	 */
759 	error = 0;
760 	for (offset = 0, resid = bp->b_resid; resid;
761 	    resid -= sz, offset += sz) {
762 		struct buf *nbp;
763 		struct vnode *vp;
764 		daddr_t nbn;
765 		int off, nra;
766 
767 		nra = 0;
768 		vn_lock(vnd->sc_vp, LK_EXCLUSIVE | LK_RETRY | LK_CANRECURSE);
769 		error = VOP_BMAP(vnd->sc_vp, bn / bsize, &vp, &nbn, &nra);
770 		VOP_UNLOCK(vnd->sc_vp, 0);
771 
772 		if (error == 0 && (long)nbn == -1)
773 			error = EIO;
774 
775 		/*
776 		 * If there was an error or a hole in the file...punt.
777 		 * Note that we may have to wait for any operations
778 		 * that we have already fired off before releasing
779 		 * the buffer.
780 		 *
781 		 * XXX we could deal with holes here but it would be
782 		 * a hassle (in the write case).
783 		 */
784 		if (error) {
785 			skipped += resid;
786 			break;
787 		}
788 
789 #ifdef DEBUG
790 		if (!dovndcluster)
791 			nra = 0;
792 #endif
793 
794 		off = bn % bsize;
795 		sz = MIN(((off_t)1 + nra) * bsize - off, resid);
796 #ifdef	DEBUG
797 		if (vnddebug & VDB_IO)
798 			printf("vndstrategy: vp %p/%p bn 0x%qx/0x%" PRIx64
799 			       " sz 0x%zx\n",
800 			    vnd->sc_vp, vp, (long long)bn, nbn, sz);
801 #endif
802 
803 		nbp = getiobuf();
804 		nestiobuf_setup(bp, nbp, offset, sz);
805 		nbp->b_blkno = nbn + btodb(off);
806 
807 #if 0 /* XXX #ifdef DEBUG */
808 		if (vnddebug & VDB_IO)
809 			printf("vndstart(%ld): bp %p vp %p blkno "
810 			    "0x%" PRIx64 " flags %x addr %p cnt 0x%x\n",
811 			    (long) (vnd-vnd_softc), &nbp->vb_buf,
812 			    nbp->vb_buf.b_vp, nbp->vb_buf.b_blkno,
813 			    nbp->vb_buf.b_flags, nbp->vb_buf.b_data,
814 			    nbp->vb_buf.b_bcount);
815 #endif
816 		VOP_STRATEGY(vp, nbp);
817 		bn += sz;
818 	}
819 	nestiobuf_done(bp, skipped, error);
820 
821 	if (!(flags & B_READ)) {
822 		KASSERT(mp != NULL);
823 		vn_finished_write(mp, 0);
824 	}
825 }
826 
827 static void
828 vndiodone(struct buf *bp)
829 {
830 	struct vndxfer *vnx = VND_BUFTOXFER(bp);
831 	struct vnd_softc *vnd = vnx->vx_vnd;
832 	struct buf *obp = bp->b_private;
833 
834 	KASSERT(&vnx->vx_buf == bp);
835 	KASSERT(vnd->sc_active > 0);
836 #ifdef DEBUG
837 	if (vnddebug & VDB_IO) {
838 		printf("vndiodone1: bp %p iodone: error %d\n",
839 		    bp, (bp->b_flags & B_ERROR) != 0 ? bp->b_error : 0);
840 	}
841 #endif
842 	disk_unbusy(&vnd->sc_dkdev, bp->b_bcount - bp->b_resid,
843 	    (bp->b_flags & B_READ));
844 	vnd->sc_active--;
845 	if (vnd->sc_active == 0) {
846 		wakeup(&vnd->sc_tab);
847 	}
848 	obp->b_flags |= bp->b_flags & B_ERROR;
849 	obp->b_error = bp->b_error;
850 	obp->b_resid = bp->b_resid;
851 	VND_PUTXFER(vnd, vnx);
852 	biodone(obp);
853 }
854 
855 /* ARGSUSED */
856 static int
857 vndread(dev_t dev, struct uio *uio, int flags)
858 {
859 	int unit = vndunit(dev);
860 	struct vnd_softc *sc;
861 
862 #ifdef DEBUG
863 	if (vnddebug & VDB_FOLLOW)
864 		printf("vndread(0x%x, %p)\n", dev, uio);
865 #endif
866 
867 	sc = device_lookup(&vnd_cd, unit);
868 	if (sc == NULL)
869 		return ENXIO;
870 
871 	if ((sc->sc_flags & VNF_INITED) == 0)
872 		return (ENXIO);
873 
874 	return (physio(vndstrategy, NULL, dev, B_READ, minphys, uio));
875 }
876 
877 /* ARGSUSED */
878 static int
879 vndwrite(dev_t dev, struct uio *uio, int flags)
880 {
881 	int unit = vndunit(dev);
882 	struct vnd_softc *sc;
883 
884 #ifdef DEBUG
885 	if (vnddebug & VDB_FOLLOW)
886 		printf("vndwrite(0x%x, %p)\n", dev, uio);
887 #endif
888 
889 	sc = device_lookup(&vnd_cd, unit);
890 	if (sc == NULL)
891 		return ENXIO;
892 
893 	if ((sc->sc_flags & VNF_INITED) == 0)
894 		return (ENXIO);
895 
896 	return (physio(vndstrategy, NULL, dev, B_WRITE, minphys, uio));
897 }
898 
899 static int
900 vnd_cget(struct lwp *l, int unit, int *un, struct vattr *va)
901 {
902 	struct vnd_softc *vnd;
903 
904 	if (*un == -1)
905 		*un = unit;
906 	if (*un < 0)
907 		return EINVAL;
908 
909 	vnd = device_lookup(&vnd_cd, *un);
910 	if (vnd == NULL)
911 		return (*un >= vnd_cd.cd_ndevs) ? ENXIO : -1;
912 
913 	if ((vnd->sc_flags & VNF_INITED) == 0)
914 		return -1;
915 
916 	return VOP_GETATTR(vnd->sc_vp, va, l->l_cred, l);
917 }
918 
919 /* ARGSUSED */
920 static int
921 vndioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct lwp *l)
922 {
923 	int unit = vndunit(dev);
924 	struct vnd_softc *vnd;
925 	struct vnd_ioctl *vio;
926 	struct vattr vattr;
927 	struct nameidata nd;
928 	int error, part, pmask;
929 	size_t geomsize;
930 	int fflags;
931 #ifdef __HAVE_OLD_DISKLABEL
932 	struct disklabel newlabel;
933 #endif
934 
935 #ifdef DEBUG
936 	if (vnddebug & VDB_FOLLOW)
937 		printf("vndioctl(0x%x, 0x%lx, %p, 0x%x, %p): unit %d\n",
938 		    dev, cmd, data, flag, l->l_proc, unit);
939 #endif
940 	vnd = device_lookup(&vnd_cd, unit);
941 	if (vnd == NULL &&
942 #ifdef COMPAT_30
943 	    cmd != VNDIOOCGET &&
944 #endif
945 	    cmd != VNDIOCGET)
946 		return ENXIO;
947 	vio = (struct vnd_ioctl *)data;
948 
949 	/* Must be open for writes for these commands... */
950 	switch (cmd) {
951 	case VNDIOCSET:
952 	case VNDIOCCLR:
953 	case DIOCSDINFO:
954 	case DIOCWDINFO:
955 #ifdef __HAVE_OLD_DISKLABEL
956 	case ODIOCSDINFO:
957 	case ODIOCWDINFO:
958 #endif
959 	case DIOCKLABEL:
960 	case DIOCWLABEL:
961 		if ((flag & FWRITE) == 0)
962 			return (EBADF);
963 	}
964 
965 	/* Must be initialized for these... */
966 	switch (cmd) {
967 	case VNDIOCCLR:
968 	case DIOCGDINFO:
969 	case DIOCSDINFO:
970 	case DIOCWDINFO:
971 	case DIOCGPART:
972 	case DIOCKLABEL:
973 	case DIOCWLABEL:
974 	case DIOCGDEFLABEL:
975 #ifdef __HAVE_OLD_DISKLABEL
976 	case ODIOCGDINFO:
977 	case ODIOCSDINFO:
978 	case ODIOCWDINFO:
979 	case ODIOCGDEFLABEL:
980 #endif
981 		if ((vnd->sc_flags & VNF_INITED) == 0)
982 			return (ENXIO);
983 	}
984 
985 	switch (cmd) {
986 	case VNDIOCSET:
987 		if (vnd->sc_flags & VNF_INITED)
988 			return (EBUSY);
989 
990 		if ((error = vndlock(vnd)) != 0)
991 			return (error);
992 
993 		fflags = FREAD;
994 		if ((vio->vnd_flags & VNDIOF_READONLY) == 0)
995 			fflags |= FWRITE;
996 		NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, vio->vnd_file, l);
997 		if ((error = vn_open(&nd, fflags, 0)) != 0)
998 			goto unlock_and_exit;
999 		KASSERT(l);
1000 		error = VOP_GETATTR(nd.ni_vp, &vattr, l->l_cred, l);
1001 		if (!error && nd.ni_vp->v_type != VREG)
1002 			error = EOPNOTSUPP;
1003 		if (error) {
1004 			VOP_UNLOCK(nd.ni_vp, 0);
1005 			goto close_and_exit;
1006 		}
1007 
1008 		/* If using a compressed file, initialize its info */
1009 		/* (or abort with an error if kernel has no compression) */
1010 		if (vio->vnd_flags & VNF_COMP) {
1011 #ifdef VND_COMPRESSION
1012 			struct vnd_comp_header *ch;
1013 			int i;
1014 			u_int32_t comp_size;
1015 			u_int32_t comp_maxsize;
1016 
1017 			/* allocate space for compresed file header */
1018 			ch = malloc(sizeof(struct vnd_comp_header),
1019 			M_TEMP, M_WAITOK);
1020 
1021 			/* read compressed file header */
1022 			error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)ch,
1023 			  sizeof(struct vnd_comp_header), 0, UIO_SYSSPACE,
1024 			  IO_UNIT|IO_NODELOCKED, l->l_cred, NULL, NULL);
1025 			if(error) {
1026 				free(ch, M_TEMP);
1027 				VOP_UNLOCK(nd.ni_vp, 0);
1028 				goto close_and_exit;
1029 			}
1030 
1031 			/* save some header info */
1032 			vnd->sc_comp_blksz = ntohl(ch->block_size);
1033 			/* note last offset is the file byte size */
1034 			vnd->sc_comp_numoffs = ntohl(ch->num_blocks)+1;
1035 			free(ch, M_TEMP);
1036 			if (vnd->sc_comp_blksz == 0 ||
1037 			    vnd->sc_comp_blksz % DEV_BSIZE !=0) {
1038 				VOP_UNLOCK(nd.ni_vp, 0);
1039 				error = EINVAL;
1040 				goto close_and_exit;
1041 			}
1042 			if(sizeof(struct vnd_comp_header) +
1043 			  sizeof(u_int64_t) * vnd->sc_comp_numoffs >
1044 			  vattr.va_size) {
1045 				VOP_UNLOCK(nd.ni_vp, 0);
1046 				error = EINVAL;
1047 				goto close_and_exit;
1048 			}
1049 
1050 			/* set decompressed file size */
1051 			vattr.va_size =
1052 			    ((u_quad_t)vnd->sc_comp_numoffs - 1) *
1053 			     (u_quad_t)vnd->sc_comp_blksz;
1054 
1055 			/* allocate space for all the compressed offsets */
1056 			vnd->sc_comp_offsets =
1057 			malloc(sizeof(u_int64_t) * vnd->sc_comp_numoffs,
1058 			M_DEVBUF, M_WAITOK);
1059 
1060 			/* read in the offsets */
1061 			error = vn_rdwr(UIO_READ, nd.ni_vp,
1062 			  (caddr_t)vnd->sc_comp_offsets,
1063 			  sizeof(u_int64_t) * vnd->sc_comp_numoffs,
1064 			  sizeof(struct vnd_comp_header), UIO_SYSSPACE,
1065 			  IO_UNIT|IO_NODELOCKED, l->l_cred, NULL, NULL);
1066 			if(error) {
1067 				VOP_UNLOCK(nd.ni_vp, 0);
1068 				goto close_and_exit;
1069 			}
1070 			/*
1071 			 * find largest block size (used for allocation limit).
1072 			 * Also convert offset to native byte order.
1073 			 */
1074 			comp_maxsize = 0;
1075 			for (i = 0; i < vnd->sc_comp_numoffs - 1; i++) {
1076 				vnd->sc_comp_offsets[i] =
1077 				  be64toh(vnd->sc_comp_offsets[i]);
1078 				comp_size = be64toh(vnd->sc_comp_offsets[i + 1])
1079 				  - vnd->sc_comp_offsets[i];
1080 				if (comp_size > comp_maxsize)
1081 					comp_maxsize = comp_size;
1082 			}
1083 			vnd->sc_comp_offsets[vnd->sc_comp_numoffs - 1] =
1084 			  be64toh(vnd->sc_comp_offsets[vnd->sc_comp_numoffs - 1]);
1085 
1086 			/* create compressed data buffer */
1087 			vnd->sc_comp_buff = malloc(comp_maxsize,
1088 			  M_DEVBUF, M_WAITOK);
1089 
1090 			/* create decompressed buffer */
1091 			vnd->sc_comp_decombuf = malloc(vnd->sc_comp_blksz,
1092 			  M_DEVBUF, M_WAITOK);
1093 			vnd->sc_comp_buffblk = -1;
1094 
1095 			/* Initialize decompress stream */
1096 			bzero(&vnd->sc_comp_stream, sizeof(z_stream));
1097 			vnd->sc_comp_stream.zalloc = vnd_alloc;
1098 			vnd->sc_comp_stream.zfree = vnd_free;
1099 			error = inflateInit2(&vnd->sc_comp_stream, MAX_WBITS);
1100 			if(error) {
1101 				if(vnd->sc_comp_stream.msg)
1102 					printf("vnd%d: compressed file, %s\n",
1103 					  unit, vnd->sc_comp_stream.msg);
1104 				VOP_UNLOCK(nd.ni_vp, 0);
1105 				error = EINVAL;
1106 				goto close_and_exit;
1107 			}
1108 
1109 			vnd->sc_flags |= VNF_COMP | VNF_READONLY;
1110 #else /* !VND_COMPRESSION */
1111 			VOP_UNLOCK(nd.ni_vp, 0);
1112 			error = EOPNOTSUPP;
1113 			goto close_and_exit;
1114 #endif /* VND_COMPRESSION */
1115 		}
1116 
1117 		VOP_UNLOCK(nd.ni_vp, 0);
1118 		vnd->sc_vp = nd.ni_vp;
1119 		vnd->sc_size = btodb(vattr.va_size);	/* note truncation */
1120 
1121 		/*
1122 		 * Use pseudo-geometry specified.  If none was provided,
1123 		 * use "standard" Adaptec fictitious geometry.
1124 		 */
1125 		if (vio->vnd_flags & VNDIOF_HASGEOM) {
1126 
1127 			memcpy(&vnd->sc_geom, &vio->vnd_geom,
1128 			    sizeof(vio->vnd_geom));
1129 
1130 			/*
1131 			 * Sanity-check the sector size.
1132 			 * XXX Don't allow secsize < DEV_BSIZE.	 Should
1133 			 * XXX we?
1134 			 */
1135 			if (vnd->sc_geom.vng_secsize < DEV_BSIZE ||
1136 			    (vnd->sc_geom.vng_secsize % DEV_BSIZE) != 0 ||
1137 			    vnd->sc_geom.vng_ncylinders == 0 ||
1138 			    (vnd->sc_geom.vng_ntracks *
1139 			     vnd->sc_geom.vng_nsectors) == 0) {
1140 				error = EINVAL;
1141 				goto close_and_exit;
1142 			}
1143 
1144 			/*
1145 			 * Compute the size (in DEV_BSIZE blocks) specified
1146 			 * by the geometry.
1147 			 */
1148 			geomsize = (vnd->sc_geom.vng_nsectors *
1149 			    vnd->sc_geom.vng_ntracks *
1150 			    vnd->sc_geom.vng_ncylinders) *
1151 			    (vnd->sc_geom.vng_secsize / DEV_BSIZE);
1152 
1153 			/*
1154 			 * Sanity-check the size against the specified
1155 			 * geometry.
1156 			 */
1157 			if (vnd->sc_size < geomsize) {
1158 				error = EINVAL;
1159 				goto close_and_exit;
1160 			}
1161 		} else if (vnd->sc_size >= (32 * 64)) {
1162 			/*
1163 			 * Size must be at least 2048 DEV_BSIZE blocks
1164 			 * (1M) in order to use this geometry.
1165 			 */
1166 			vnd->sc_geom.vng_secsize = DEV_BSIZE;
1167 			vnd->sc_geom.vng_nsectors = 32;
1168 			vnd->sc_geom.vng_ntracks = 64;
1169 			vnd->sc_geom.vng_ncylinders = vnd->sc_size / (64 * 32);
1170 		} else {
1171 			vnd->sc_geom.vng_secsize = DEV_BSIZE;
1172 			vnd->sc_geom.vng_nsectors = 1;
1173 			vnd->sc_geom.vng_ntracks = 1;
1174 			vnd->sc_geom.vng_ncylinders = vnd->sc_size;
1175 		}
1176 
1177 		if (vio->vnd_flags & VNDIOF_READONLY) {
1178 			vnd->sc_flags |= VNF_READONLY;
1179 		}
1180 
1181 		if ((error = vndsetcred(vnd, l->l_cred)) != 0)
1182 			goto close_and_exit;
1183 
1184 		vndthrottle(vnd, vnd->sc_vp);
1185 		vio->vnd_size = dbtob(vnd->sc_size);
1186 		vnd->sc_flags |= VNF_INITED;
1187 
1188 		/* create the kernel thread, wait for it to be up */
1189 		error = kthread_create1(vndthread, vnd, &vnd->sc_kthread,
1190 		    vnd->sc_dev.dv_xname);
1191 		if (error)
1192 			goto close_and_exit;
1193 		while ((vnd->sc_flags & VNF_KTHREAD) == 0) {
1194 			tsleep(&vnd->sc_kthread, PRIBIO, "vndthr", 0);
1195 		}
1196 #ifdef DEBUG
1197 		if (vnddebug & VDB_INIT)
1198 			printf("vndioctl: SET vp %p size 0x%lx %d/%d/%d/%d\n",
1199 			    vnd->sc_vp, (unsigned long) vnd->sc_size,
1200 			    vnd->sc_geom.vng_secsize,
1201 			    vnd->sc_geom.vng_nsectors,
1202 			    vnd->sc_geom.vng_ntracks,
1203 			    vnd->sc_geom.vng_ncylinders);
1204 #endif
1205 
1206 		/* Attach the disk. */
1207 		vnd->sc_dkdev.dk_name = vnd->sc_dev.dv_xname;
1208 		pseudo_disk_attach(&vnd->sc_dkdev);
1209 
1210 		/* Initialize the xfer and buffer pools. */
1211 		pool_init(&vnd->sc_vxpool, sizeof(struct vndxfer), 0,
1212 		    0, 0, "vndxpl", NULL);
1213 
1214 		/* Try and read the disklabel. */
1215 		vndgetdisklabel(dev, vnd);
1216 
1217 		vndunlock(vnd);
1218 
1219 		break;
1220 
1221 close_and_exit:
1222 		(void) vn_close(nd.ni_vp, fflags, l->l_cred, l);
1223 unlock_and_exit:
1224 #ifdef VND_COMPRESSION
1225 		/* free any allocated memory (for compressed file) */
1226 		if(vnd->sc_comp_offsets) {
1227 			free(vnd->sc_comp_offsets, M_DEVBUF);
1228 			vnd->sc_comp_offsets = NULL;
1229 		}
1230 		if(vnd->sc_comp_buff) {
1231 			free(vnd->sc_comp_buff, M_DEVBUF);
1232 			vnd->sc_comp_buff = NULL;
1233 		}
1234 		if(vnd->sc_comp_decombuf) {
1235 			free(vnd->sc_comp_decombuf, M_DEVBUF);
1236 			vnd->sc_comp_decombuf = NULL;
1237 		}
1238 #endif /* VND_COMPRESSION */
1239 		vndunlock(vnd);
1240 		return (error);
1241 
1242 	case VNDIOCCLR:
1243 		if ((error = vndlock(vnd)) != 0)
1244 			return (error);
1245 
1246 		/*
1247 		 * Don't unconfigure if any other partitions are open
1248 		 * or if both the character and block flavors of this
1249 		 * partition are open.
1250 		 */
1251 		part = DISKPART(dev);
1252 		pmask = (1 << part);
1253 		if (((vnd->sc_dkdev.dk_openmask & ~pmask) ||
1254 		    ((vnd->sc_dkdev.dk_bopenmask & pmask) &&
1255 		    (vnd->sc_dkdev.dk_copenmask & pmask))) &&
1256 			!(vio->vnd_flags & VNDIOF_FORCE)) {
1257 			vndunlock(vnd);
1258 			return (EBUSY);
1259 		}
1260 
1261 		/*
1262 		 * XXX vndclear() might call vndclose() implicitely;
1263 		 * release lock to avoid recursion
1264 		 */
1265 		vndunlock(vnd);
1266 		vndclear(vnd, minor(dev));
1267 #ifdef DEBUG
1268 		if (vnddebug & VDB_INIT)
1269 			printf("vndioctl: CLRed\n");
1270 #endif
1271 
1272 		/* Destroy the xfer and buffer pools. */
1273 		pool_destroy(&vnd->sc_vxpool);
1274 
1275 		/* Detatch the disk. */
1276 		pseudo_disk_detach(&vnd->sc_dkdev);
1277 		break;
1278 
1279 #ifdef COMPAT_30
1280 	case VNDIOOCGET: {
1281 		struct vnd_ouser *vnu;
1282 		struct vattr va;
1283 		vnu = (struct vnd_ouser *)data;
1284 		KASSERT(l);
1285 		switch (error = vnd_cget(l, unit, &vnu->vnu_unit, &va)) {
1286 		case 0:
1287 			vnu->vnu_dev = va.va_fsid;
1288 			vnu->vnu_ino = va.va_fileid;
1289 			break;
1290 		case -1:
1291 			/* unused is not an error */
1292 			vnu->vnu_dev = 0;
1293 			vnu->vnu_ino = 0;
1294 			break;
1295 		default:
1296 			return error;
1297 		}
1298 		break;
1299 	}
1300 #endif
1301 	case VNDIOCGET: {
1302 		struct vnd_user *vnu;
1303 		struct vattr va;
1304 		vnu = (struct vnd_user *)data;
1305 		KASSERT(l);
1306 		switch (error = vnd_cget(l, unit, &vnu->vnu_unit, &va)) {
1307 		case 0:
1308 			vnu->vnu_dev = va.va_fsid;
1309 			vnu->vnu_ino = va.va_fileid;
1310 			break;
1311 		case -1:
1312 			/* unused is not an error */
1313 			vnu->vnu_dev = 0;
1314 			vnu->vnu_ino = 0;
1315 			break;
1316 		default:
1317 			return error;
1318 		}
1319 		break;
1320 	}
1321 
1322 	case DIOCGDINFO:
1323 		*(struct disklabel *)data = *(vnd->sc_dkdev.dk_label);
1324 		break;
1325 
1326 #ifdef __HAVE_OLD_DISKLABEL
1327 	case ODIOCGDINFO:
1328 		newlabel = *(vnd->sc_dkdev.dk_label);
1329 		if (newlabel.d_npartitions > OLDMAXPARTITIONS)
1330 			return ENOTTY;
1331 		memcpy(data, &newlabel, sizeof (struct olddisklabel));
1332 		break;
1333 #endif
1334 
1335 	case DIOCGPART:
1336 		((struct partinfo *)data)->disklab = vnd->sc_dkdev.dk_label;
1337 		((struct partinfo *)data)->part =
1338 		    &vnd->sc_dkdev.dk_label->d_partitions[DISKPART(dev)];
1339 		break;
1340 
1341 	case DIOCWDINFO:
1342 	case DIOCSDINFO:
1343 #ifdef __HAVE_OLD_DISKLABEL
1344 	case ODIOCWDINFO:
1345 	case ODIOCSDINFO:
1346 #endif
1347 	{
1348 		struct disklabel *lp;
1349 
1350 		if ((error = vndlock(vnd)) != 0)
1351 			return (error);
1352 
1353 		vnd->sc_flags |= VNF_LABELLING;
1354 
1355 #ifdef __HAVE_OLD_DISKLABEL
1356 		if (cmd == ODIOCSDINFO || cmd == ODIOCWDINFO) {
1357 			memset(&newlabel, 0, sizeof newlabel);
1358 			memcpy(&newlabel, data, sizeof (struct olddisklabel));
1359 			lp = &newlabel;
1360 		} else
1361 #endif
1362 		lp = (struct disklabel *)data;
1363 
1364 		error = setdisklabel(vnd->sc_dkdev.dk_label,
1365 		    lp, 0, vnd->sc_dkdev.dk_cpulabel);
1366 		if (error == 0) {
1367 			if (cmd == DIOCWDINFO
1368 #ifdef __HAVE_OLD_DISKLABEL
1369 			    || cmd == ODIOCWDINFO
1370 #endif
1371 			   )
1372 				error = writedisklabel(VNDLABELDEV(dev),
1373 				    vndstrategy, vnd->sc_dkdev.dk_label,
1374 				    vnd->sc_dkdev.dk_cpulabel);
1375 		}
1376 
1377 		vnd->sc_flags &= ~VNF_LABELLING;
1378 
1379 		vndunlock(vnd);
1380 
1381 		if (error)
1382 			return (error);
1383 		break;
1384 	}
1385 
1386 	case DIOCKLABEL:
1387 		if (*(int *)data != 0)
1388 			vnd->sc_flags |= VNF_KLABEL;
1389 		else
1390 			vnd->sc_flags &= ~VNF_KLABEL;
1391 		break;
1392 
1393 	case DIOCWLABEL:
1394 		if (*(int *)data != 0)
1395 			vnd->sc_flags |= VNF_WLABEL;
1396 		else
1397 			vnd->sc_flags &= ~VNF_WLABEL;
1398 		break;
1399 
1400 	case DIOCGDEFLABEL:
1401 		vndgetdefaultlabel(vnd, (struct disklabel *)data);
1402 		break;
1403 
1404 #ifdef __HAVE_OLD_DISKLABEL
1405 	case ODIOCGDEFLABEL:
1406 		vndgetdefaultlabel(vnd, &newlabel);
1407 		if (newlabel.d_npartitions > OLDMAXPARTITIONS)
1408 			return ENOTTY;
1409 		memcpy(data, &newlabel, sizeof (struct olddisklabel));
1410 		break;
1411 #endif
1412 
1413 	default:
1414 		return (ENOTTY);
1415 	}
1416 
1417 	return (0);
1418 }
1419 
1420 /*
1421  * Duplicate the current processes' credentials.  Since we are called only
1422  * as the result of a SET ioctl and only root can do that, any future access
1423  * to this "disk" is essentially as root.  Note that credentials may change
1424  * if some other uid can write directly to the mapped file (NFS).
1425  */
1426 static int
1427 vndsetcred(struct vnd_softc *vnd, kauth_cred_t cred)
1428 {
1429 	struct uio auio;
1430 	struct iovec aiov;
1431 	char *tmpbuf;
1432 	int error;
1433 
1434 	vnd->sc_cred = kauth_cred_dup(cred);
1435 	tmpbuf = malloc(DEV_BSIZE, M_TEMP, M_WAITOK);
1436 
1437 	/* XXX: Horrible kludge to establish credentials for NFS */
1438 	aiov.iov_base = tmpbuf;
1439 	aiov.iov_len = min(DEV_BSIZE, dbtob(vnd->sc_size));
1440 	auio.uio_iov = &aiov;
1441 	auio.uio_iovcnt = 1;
1442 	auio.uio_offset = 0;
1443 	auio.uio_rw = UIO_READ;
1444 	auio.uio_resid = aiov.iov_len;
1445 	UIO_SETUP_SYSSPACE(&auio);
1446 	vn_lock(vnd->sc_vp, LK_EXCLUSIVE | LK_RETRY);
1447 	error = VOP_READ(vnd->sc_vp, &auio, 0, vnd->sc_cred);
1448 	if (error == 0) {
1449 		/*
1450 		 * Because vnd does all IO directly through the vnode
1451 		 * we need to flush (at least) the buffer from the above
1452 		 * VOP_READ from the buffer cache to prevent cache
1453 		 * incoherencies.  Also, be careful to write dirty
1454 		 * buffers back to stable storage.
1455 		 */
1456 		error = vinvalbuf(vnd->sc_vp, V_SAVE, vnd->sc_cred,
1457 			    curlwp, 0, 0);
1458 	}
1459 	VOP_UNLOCK(vnd->sc_vp, 0);
1460 
1461 	free(tmpbuf, M_TEMP);
1462 	return (error);
1463 }
1464 
1465 /*
1466  * Set maxactive based on FS type
1467  */
1468 static void
1469 vndthrottle(struct vnd_softc *vnd, struct vnode *vp)
1470 {
1471 #ifdef NFS
1472 	extern int (**nfsv2_vnodeop_p)(void *);
1473 
1474 	if (vp->v_op == nfsv2_vnodeop_p)
1475 		vnd->sc_maxactive = 2;
1476 	else
1477 #endif
1478 		vnd->sc_maxactive = 8;
1479 
1480 	if (vnd->sc_maxactive < 1)
1481 		vnd->sc_maxactive = 1;
1482 }
1483 
1484 #if 0
1485 static void
1486 vndshutdown(void)
1487 {
1488 	struct vnd_softc *vnd;
1489 
1490 	for (vnd = &vnd_softc[0]; vnd < &vnd_softc[numvnd]; vnd++)
1491 		if (vnd->sc_flags & VNF_INITED)
1492 			vndclear(vnd);
1493 }
1494 #endif
1495 
1496 static void
1497 vndclear(struct vnd_softc *vnd, int myminor)
1498 {
1499 	struct vnode *vp = vnd->sc_vp;
1500 	struct lwp *l = curlwp;
1501 	int fflags = FREAD;
1502 	int bmaj, cmaj, i, mn;
1503 	int s;
1504 
1505 #ifdef DEBUG
1506 	if (vnddebug & VDB_FOLLOW)
1507 		printf("vndclear(%p): vp %p\n", vnd, vp);
1508 #endif
1509 	/* locate the major number */
1510 	bmaj = bdevsw_lookup_major(&vnd_bdevsw);
1511 	cmaj = cdevsw_lookup_major(&vnd_cdevsw);
1512 
1513 	/* Nuke the vnodes for any open instances */
1514 	for (i = 0; i < MAXPARTITIONS; i++) {
1515 		mn = DISKMINOR(device_unit(&vnd->sc_dev), i);
1516 		vdevgone(bmaj, mn, mn, VBLK);
1517 		if (mn != myminor) /* XXX avoid to kill own vnode */
1518 			vdevgone(cmaj, mn, mn, VCHR);
1519 	}
1520 
1521 	if ((vnd->sc_flags & VNF_READONLY) == 0)
1522 		fflags |= FWRITE;
1523 
1524 	s = splbio();
1525 	bufq_drain(vnd->sc_tab);
1526 	splx(s);
1527 
1528 	vnd->sc_flags |= VNF_VUNCONF;
1529 	wakeup(&vnd->sc_tab);
1530 	while (vnd->sc_flags & VNF_KTHREAD)
1531 		tsleep(&vnd->sc_kthread, PRIBIO, "vnthr", 0);
1532 
1533 #ifdef VND_COMPRESSION
1534 	/* free the compressed file buffers */
1535 	if(vnd->sc_flags & VNF_COMP) {
1536 		if(vnd->sc_comp_offsets) {
1537 			free(vnd->sc_comp_offsets, M_DEVBUF);
1538 			vnd->sc_comp_offsets = NULL;
1539 		}
1540 		if(vnd->sc_comp_buff) {
1541 			free(vnd->sc_comp_buff, M_DEVBUF);
1542 			vnd->sc_comp_buff = NULL;
1543 		}
1544 		if(vnd->sc_comp_decombuf) {
1545 			free(vnd->sc_comp_decombuf, M_DEVBUF);
1546 			vnd->sc_comp_decombuf = NULL;
1547 		}
1548 	}
1549 #endif /* VND_COMPRESSION */
1550 	vnd->sc_flags &=
1551 	    ~(VNF_INITED | VNF_READONLY | VNF_VLABEL
1552 	      | VNF_VUNCONF | VNF_COMP);
1553 	if (vp == (struct vnode *)0)
1554 		panic("vndclear: null vp");
1555 	(void) vn_close(vp, fflags, vnd->sc_cred, l);
1556 	kauth_cred_free(vnd->sc_cred);
1557 	vnd->sc_vp = (struct vnode *)0;
1558 	vnd->sc_cred = (kauth_cred_t)0;
1559 	vnd->sc_size = 0;
1560 }
1561 
1562 static int
1563 vndsize(dev_t dev)
1564 {
1565 	struct vnd_softc *sc;
1566 	struct disklabel *lp;
1567 	int part, unit, omask;
1568 	int size;
1569 
1570 	unit = vndunit(dev);
1571 	sc = (struct vnd_softc *)device_lookup(&vnd_cd, unit);
1572 	if (sc == NULL)
1573 		return -1;
1574 
1575 	if ((sc->sc_flags & VNF_INITED) == 0)
1576 		return (-1);
1577 
1578 	part = DISKPART(dev);
1579 	omask = sc->sc_dkdev.dk_openmask & (1 << part);
1580 	lp = sc->sc_dkdev.dk_label;
1581 
1582 	if (omask == 0 && vndopen(dev, 0, S_IFBLK, curlwp))	/* XXX */
1583 		return (-1);
1584 
1585 	if (lp->d_partitions[part].p_fstype != FS_SWAP)
1586 		size = -1;
1587 	else
1588 		size = lp->d_partitions[part].p_size *
1589 		    (lp->d_secsize / DEV_BSIZE);
1590 
1591 	if (omask == 0 && vndclose(dev, 0, S_IFBLK, curlwp))	/* XXX */
1592 		return (-1);
1593 
1594 	return (size);
1595 }
1596 
1597 static int
1598 vnddump(dev_t dev, daddr_t blkno, caddr_t va,
1599     size_t size)
1600 {
1601 
1602 	/* Not implemented. */
1603 	return ENXIO;
1604 }
1605 
1606 static void
1607 vndgetdefaultlabel(struct vnd_softc *sc, struct disklabel *lp)
1608 {
1609 	struct vndgeom *vng = &sc->sc_geom;
1610 	struct partition *pp;
1611 
1612 	memset(lp, 0, sizeof(*lp));
1613 
1614 	lp->d_secperunit = sc->sc_size / (vng->vng_secsize / DEV_BSIZE);
1615 	lp->d_secsize = vng->vng_secsize;
1616 	lp->d_nsectors = vng->vng_nsectors;
1617 	lp->d_ntracks = vng->vng_ntracks;
1618 	lp->d_ncylinders = vng->vng_ncylinders;
1619 	lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors;
1620 
1621 	strncpy(lp->d_typename, "vnd", sizeof(lp->d_typename));
1622 	lp->d_type = DTYPE_VND;
1623 	strncpy(lp->d_packname, "fictitious", sizeof(lp->d_packname));
1624 	lp->d_rpm = 3600;
1625 	lp->d_interleave = 1;
1626 	lp->d_flags = 0;
1627 
1628 	pp = &lp->d_partitions[RAW_PART];
1629 	pp->p_offset = 0;
1630 	pp->p_size = lp->d_secperunit;
1631 	pp->p_fstype = FS_UNUSED;
1632 	lp->d_npartitions = RAW_PART + 1;
1633 
1634 	lp->d_magic = DISKMAGIC;
1635 	lp->d_magic2 = DISKMAGIC;
1636 	lp->d_checksum = dkcksum(lp);
1637 }
1638 
1639 /*
1640  * Read the disklabel from a vnd.  If one is not present, create a fake one.
1641  */
1642 static void
1643 vndgetdisklabel(dev_t dev, struct vnd_softc *sc)
1644 {
1645 	const char *errstring;
1646 	struct disklabel *lp = sc->sc_dkdev.dk_label;
1647 	struct cpu_disklabel *clp = sc->sc_dkdev.dk_cpulabel;
1648 	int i;
1649 
1650 	memset(clp, 0, sizeof(*clp));
1651 
1652 	vndgetdefaultlabel(sc, lp);
1653 
1654 	/*
1655 	 * Call the generic disklabel extraction routine.
1656 	 */
1657 	errstring = readdisklabel(VNDLABELDEV(dev), vndstrategy, lp, clp);
1658 	if (errstring) {
1659 		/*
1660 		 * Lack of disklabel is common, but we print the warning
1661 		 * anyway, since it might contain other useful information.
1662 		 */
1663 		printf("%s: %s\n", sc->sc_dev.dv_xname, errstring);
1664 
1665 		/*
1666 		 * For historical reasons, if there's no disklabel
1667 		 * present, all partitions must be FS_BSDFFS and
1668 		 * occupy the entire disk.
1669 		 */
1670 		for (i = 0; i < MAXPARTITIONS; i++) {
1671 			/*
1672 			 * Don't wipe out port specific hack (such as
1673 			 * dos partition hack of i386 port).
1674 			 */
1675 			if (lp->d_partitions[i].p_size != 0)
1676 				continue;
1677 
1678 			lp->d_partitions[i].p_size = lp->d_secperunit;
1679 			lp->d_partitions[i].p_offset = 0;
1680 			lp->d_partitions[i].p_fstype = FS_BSDFFS;
1681 		}
1682 
1683 		strncpy(lp->d_packname, "default label",
1684 		    sizeof(lp->d_packname));
1685 
1686 		lp->d_npartitions = MAXPARTITIONS;
1687 		lp->d_checksum = dkcksum(lp);
1688 	}
1689 
1690 	/* In-core label now valid. */
1691 	sc->sc_flags |= VNF_VLABEL;
1692 }
1693 
1694 /*
1695  * Wait interruptibly for an exclusive lock.
1696  *
1697  * XXX
1698  * Several drivers do this; it should be abstracted and made MP-safe.
1699  */
1700 static int
1701 vndlock(struct vnd_softc *sc)
1702 {
1703 	int error;
1704 
1705 	while ((sc->sc_flags & VNF_LOCKED) != 0) {
1706 		sc->sc_flags |= VNF_WANTED;
1707 		if ((error = tsleep(sc, PRIBIO | PCATCH, "vndlck", 0)) != 0)
1708 			return (error);
1709 	}
1710 	sc->sc_flags |= VNF_LOCKED;
1711 	return (0);
1712 }
1713 
1714 /*
1715  * Unlock and wake up any waiters.
1716  */
1717 static void
1718 vndunlock(struct vnd_softc *sc)
1719 {
1720 
1721 	sc->sc_flags &= ~VNF_LOCKED;
1722 	if ((sc->sc_flags & VNF_WANTED) != 0) {
1723 		sc->sc_flags &= ~VNF_WANTED;
1724 		wakeup(sc);
1725 	}
1726 }
1727 
1728 #ifdef VND_COMPRESSION
1729 /* compressed file read */
1730 static void
1731 compstrategy(struct buf *bp, off_t bn)
1732 {
1733 	int error;
1734 	int unit = vndunit(bp->b_dev);
1735 	struct vnd_softc *vnd =
1736 	    (struct vnd_softc *)device_lookup(&vnd_cd, unit);
1737 	u_int32_t comp_block;
1738 	struct uio auio;
1739 	caddr_t addr;
1740 	int s;
1741 
1742 	/* set up constants for data move */
1743 	auio.uio_rw = UIO_READ;
1744 	UIO_SETUP_SYSSPACE(&auio);
1745 
1746 	/* read, and transfer the data */
1747 	addr = bp->b_data;
1748 	s = splbio();
1749 	while (bp->b_resid > 0) {
1750 		unsigned length;
1751 		size_t length_in_buffer;
1752 		u_int32_t offset_in_buffer;
1753 		struct iovec aiov;
1754 
1755 		/* calculate the compressed block number */
1756 		comp_block = bn / (off_t)vnd->sc_comp_blksz;
1757 
1758 		/* check for good block number */
1759 		if (comp_block >= vnd->sc_comp_numoffs) {
1760 			bp->b_error = EINVAL;
1761 			bp->b_flags |= B_ERROR;
1762 			splx(s);
1763 			return;
1764 		}
1765 
1766 		/* read in the compressed block, if not in buffer */
1767 		if (comp_block != vnd->sc_comp_buffblk) {
1768 			length = vnd->sc_comp_offsets[comp_block + 1] -
1769 			    vnd->sc_comp_offsets[comp_block];
1770 			vn_lock(vnd->sc_vp, LK_EXCLUSIVE | LK_RETRY);
1771 			error = vn_rdwr(UIO_READ, vnd->sc_vp, vnd->sc_comp_buff,
1772 			    length, vnd->sc_comp_offsets[comp_block],
1773 			    UIO_SYSSPACE, IO_UNIT, vnd->sc_cred, NULL, NULL);
1774 			if (error) {
1775 				bp->b_error = error;
1776 				bp->b_flags |= B_ERROR;
1777 				VOP_UNLOCK(vnd->sc_vp, 0);
1778 				splx(s);
1779 				return;
1780 			}
1781 			/* uncompress the buffer */
1782 			vnd->sc_comp_stream.next_in = vnd->sc_comp_buff;
1783 			vnd->sc_comp_stream.avail_in = length;
1784 			vnd->sc_comp_stream.next_out = vnd->sc_comp_decombuf;
1785 			vnd->sc_comp_stream.avail_out = vnd->sc_comp_blksz;
1786 			inflateReset(&vnd->sc_comp_stream);
1787 			error = inflate(&vnd->sc_comp_stream, Z_FINISH);
1788 			if (error != Z_STREAM_END) {
1789 				if (vnd->sc_comp_stream.msg)
1790 					printf("%s: compressed file, %s\n",
1791 					    vnd->sc_dev.dv_xname,
1792 					    vnd->sc_comp_stream.msg);
1793 				bp->b_error = EBADMSG;
1794 				bp->b_flags |= B_ERROR;
1795 				VOP_UNLOCK(vnd->sc_vp, 0);
1796 				splx(s);
1797 				return;
1798 			}
1799 			vnd->sc_comp_buffblk = comp_block;
1800 			VOP_UNLOCK(vnd->sc_vp, 0);
1801 		}
1802 
1803 		/* transfer the usable uncompressed data */
1804 		offset_in_buffer = bn % (off_t)vnd->sc_comp_blksz;
1805 		length_in_buffer = vnd->sc_comp_blksz - offset_in_buffer;
1806 		if (length_in_buffer > bp->b_resid)
1807 			length_in_buffer = bp->b_resid;
1808 		auio.uio_iov = &aiov;
1809 		auio.uio_iovcnt = 1;
1810 		aiov.iov_base = addr;
1811 		aiov.iov_len = length_in_buffer;
1812 		auio.uio_resid = aiov.iov_len;
1813 		auio.uio_offset = 0;
1814 		error = uiomove(vnd->sc_comp_decombuf + offset_in_buffer,
1815 		    length_in_buffer, &auio);
1816 		if (error) {
1817 			bp->b_error = error;
1818 			bp->b_flags |= B_ERROR;
1819 			splx(s);
1820 			return;
1821 		}
1822 
1823 		bn += length_in_buffer;
1824 		addr += length_in_buffer;
1825 		bp->b_resid -= length_in_buffer;
1826 	}
1827 	splx(s);
1828 }
1829 
1830 /* compression memory allocation routines */
1831 static void *
1832 vnd_alloc(void *aux, u_int items, u_int siz)
1833 {
1834 	return malloc(items * siz, M_TEMP, M_NOWAIT);
1835 }
1836 
1837 static void
1838 vnd_free(void *aux, void *ptr)
1839 {
1840 	free(ptr, M_TEMP);
1841 }
1842 #endif /* VND_COMPRESSION */
1843