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vnd.c revision 1.267
      1 /*	$NetBSD: vnd.c,v 1.267 2018/10/07 11:51:26 mlelstv Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1996, 1997, 1998, 2008 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  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Copyright (c) 1988 University of Utah.
     34  * Copyright (c) 1990, 1993
     35  *	The Regents of the University of California.  All rights reserved.
     36  *
     37  * This code is derived from software contributed to Berkeley by
     38  * the Systems Programming Group of the University of Utah Computer
     39  * Science Department.
     40  *
     41  * Redistribution and use in source and binary forms, with or without
     42  * modification, are permitted provided that the following conditions
     43  * are met:
     44  * 1. Redistributions of source code must retain the above copyright
     45  *    notice, this list of conditions and the following disclaimer.
     46  * 2. Redistributions in binary form must reproduce the above copyright
     47  *    notice, this list of conditions and the following disclaimer in the
     48  *    documentation and/or other materials provided with the distribution.
     49  * 3. Neither the name of the University nor the names of its contributors
     50  *    may be used to endorse or promote products derived from this software
     51  *    without specific prior written permission.
     52  *
     53  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     63  * SUCH DAMAGE.
     64  *
     65  * from: Utah $Hdr: vn.c 1.13 94/04/02$
     66  *
     67  *	@(#)vn.c	8.9 (Berkeley) 5/14/95
     68  */
     69 
     70 /*
     71  * Vnode disk driver.
     72  *
     73  * Block/character interface to a vnode.  Allows one to treat a file
     74  * as a disk (e.g. build a filesystem in it, mount it, etc.).
     75  *
     76  * NOTE 1: If the vnode supports the VOP_BMAP and VOP_STRATEGY operations,
     77  * this uses them to avoid distorting the local buffer cache.  If those
     78  * block-level operations are not available, this falls back to the regular
     79  * read and write calls.  Using these may distort the cache in some cases
     80  * but better have the driver working than preventing it to work on file
     81  * systems where the block-level operations are not implemented for
     82  * whatever reason.
     83  *
     84  * NOTE 2: There is a security issue involved with this driver.
     85  * Once mounted all access to the contents of the "mapped" file via
     86  * the special file is controlled by the permissions on the special
     87  * file, the protection of the mapped file is ignored (effectively,
     88  * by using root credentials in all transactions).
     89  *
     90  * NOTE 3: Doesn't interact with leases, should it?
     91  */
     92 
     93 #include <sys/cdefs.h>
     94 __KERNEL_RCSID(0, "$NetBSD: vnd.c,v 1.267 2018/10/07 11:51:26 mlelstv Exp $");
     95 
     96 #if defined(_KERNEL_OPT)
     97 #include "opt_vnd.h"
     98 #include "opt_compat_netbsd.h"
     99 #endif
    100 
    101 #include <sys/param.h>
    102 #include <sys/systm.h>
    103 #include <sys/namei.h>
    104 #include <sys/proc.h>
    105 #include <sys/kthread.h>
    106 #include <sys/errno.h>
    107 #include <sys/buf.h>
    108 #include <sys/bufq.h>
    109 #include <sys/malloc.h>
    110 #include <sys/ioctl.h>
    111 #include <sys/disklabel.h>
    112 #include <sys/device.h>
    113 #include <sys/disk.h>
    114 #include <sys/stat.h>
    115 #include <sys/mount.h>
    116 #include <sys/vnode.h>
    117 #include <sys/fstrans.h>
    118 #include <sys/file.h>
    119 #include <sys/uio.h>
    120 #include <sys/conf.h>
    121 #include <sys/kauth.h>
    122 #include <sys/module.h>
    123 
    124 #include <net/zlib.h>
    125 
    126 #include <miscfs/genfs/genfs.h>
    127 #include <miscfs/specfs/specdev.h>
    128 
    129 #include <dev/dkvar.h>
    130 #include <dev/vndvar.h>
    131 
    132 #include "ioconf.h"
    133 
    134 #if defined(VNDDEBUG) && !defined(DEBUG)
    135 #define DEBUG
    136 #endif
    137 
    138 #ifdef DEBUG
    139 int dovndcluster = 1;
    140 #define VDB_FOLLOW	0x01
    141 #define VDB_INIT	0x02
    142 #define VDB_IO		0x04
    143 #define VDB_LABEL	0x08
    144 int vnddebug = 0;
    145 #endif
    146 
    147 #define vndunit(x)	DISKUNIT(x)
    148 
    149 struct vndxfer {
    150 	struct buf vx_buf;
    151 	struct vnd_softc *vx_vnd;
    152 };
    153 #define	VND_BUFTOXFER(bp)	((struct vndxfer *)(void *)bp)
    154 
    155 #define VND_GETXFER(vnd)	pool_get(&(vnd)->sc_vxpool, PR_WAITOK)
    156 #define VND_PUTXFER(vnd, vx)	pool_put(&(vnd)->sc_vxpool, (vx))
    157 
    158 #define VNDLABELDEV(dev) \
    159     (MAKEDISKDEV(major((dev)), vndunit((dev)), RAW_PART))
    160 
    161 #define	VND_MAXPENDING(vnd)	((vnd)->sc_maxactive * 4)
    162 
    163 
    164 static void	vndclear(struct vnd_softc *, int);
    165 static int	vnddoclear(struct vnd_softc *, int, int, bool);
    166 static int	vndsetcred(struct vnd_softc *, kauth_cred_t);
    167 static void	vndthrottle(struct vnd_softc *, struct vnode *);
    168 static void	vndiodone(struct buf *);
    169 #if 0
    170 static void	vndshutdown(void);
    171 #endif
    172 
    173 static void	vndgetdefaultlabel(struct vnd_softc *, struct disklabel *);
    174 static void	vndgetdisklabel(dev_t, struct vnd_softc *);
    175 
    176 static int	vndlock(struct vnd_softc *);
    177 static void	vndunlock(struct vnd_softc *);
    178 #ifdef VND_COMPRESSION
    179 static void	compstrategy(struct buf *, off_t);
    180 static void	*vnd_alloc(void *, u_int, u_int);
    181 static void	vnd_free(void *, void *);
    182 #endif /* VND_COMPRESSION */
    183 
    184 static void	vndthread(void *);
    185 static bool	vnode_has_op(const struct vnode *, int);
    186 static void	handle_with_rdwr(struct vnd_softc *, const struct buf *,
    187 		    struct buf *);
    188 static void	handle_with_strategy(struct vnd_softc *, const struct buf *,
    189 		    struct buf *);
    190 static void	vnd_set_geometry(struct vnd_softc *);
    191 
    192 static dev_type_open(vndopen);
    193 static dev_type_close(vndclose);
    194 static dev_type_read(vndread);
    195 static dev_type_write(vndwrite);
    196 static dev_type_ioctl(vndioctl);
    197 static dev_type_strategy(vndstrategy);
    198 static dev_type_dump(vnddump);
    199 static dev_type_size(vndsize);
    200 
    201 const struct bdevsw vnd_bdevsw = {
    202 	.d_open = vndopen,
    203 	.d_close = vndclose,
    204 	.d_strategy = vndstrategy,
    205 	.d_ioctl = vndioctl,
    206 	.d_dump = vnddump,
    207 	.d_psize = vndsize,
    208 	.d_discard = nodiscard,
    209 	.d_flag = D_DISK
    210 };
    211 
    212 const struct cdevsw vnd_cdevsw = {
    213 	.d_open = vndopen,
    214 	.d_close = vndclose,
    215 	.d_read = vndread,
    216 	.d_write = vndwrite,
    217 	.d_ioctl = vndioctl,
    218 	.d_stop = nostop,
    219 	.d_tty = notty,
    220 	.d_poll = nopoll,
    221 	.d_mmap = nommap,
    222 	.d_kqfilter = nokqfilter,
    223 	.d_discard = nodiscard,
    224 	.d_flag = D_DISK
    225 };
    226 
    227 static int	vnd_match(device_t, cfdata_t, void *);
    228 static void	vnd_attach(device_t, device_t, void *);
    229 static int	vnd_detach(device_t, int);
    230 
    231 CFATTACH_DECL3_NEW(vnd, sizeof(struct vnd_softc),
    232     vnd_match, vnd_attach, vnd_detach, NULL, NULL, NULL, DVF_DETACH_SHUTDOWN);
    233 
    234 static struct vnd_softc	*vnd_spawn(int);
    235 int	vnd_destroy(device_t);
    236 
    237 static struct	dkdriver vnddkdriver = {
    238 	.d_strategy = vndstrategy,
    239 	.d_minphys = minphys
    240 };
    241 
    242 void
    243 vndattach(int num)
    244 {
    245 	int error;
    246 
    247 	error = config_cfattach_attach(vnd_cd.cd_name, &vnd_ca);
    248 	if (error)
    249 		aprint_error("%s: unable to register cfattach, error = %d\n",
    250 		    vnd_cd.cd_name, error);
    251 }
    252 
    253 static int
    254 vnd_match(device_t self, cfdata_t cfdata, void *aux)
    255 {
    256 
    257 	return 1;
    258 }
    259 
    260 static void
    261 vnd_attach(device_t parent, device_t self, void *aux)
    262 {
    263 	struct vnd_softc *sc = device_private(self);
    264 
    265 	sc->sc_dev = self;
    266 	sc->sc_comp_offsets = NULL;
    267 	sc->sc_comp_buff = NULL;
    268 	sc->sc_comp_decombuf = NULL;
    269 	bufq_alloc(&sc->sc_tab, "disksort", BUFQ_SORT_RAWBLOCK);
    270 	disk_init(&sc->sc_dkdev, device_xname(self), &vnddkdriver);
    271 	if (!pmf_device_register(self, NULL, NULL))
    272 		aprint_error_dev(self, "couldn't establish power handler\n");
    273 }
    274 
    275 static int
    276 vnd_detach(device_t self, int flags)
    277 {
    278 	int error;
    279 	struct vnd_softc *sc = device_private(self);
    280 
    281 	if (sc->sc_flags & VNF_INITED) {
    282 		error = vnddoclear(sc, 0, -1, (flags & DETACH_FORCE) != 0);
    283 		if (error != 0)
    284 			return error;
    285 	}
    286 
    287 	pmf_device_deregister(self);
    288 	bufq_free(sc->sc_tab);
    289 	disk_destroy(&sc->sc_dkdev);
    290 
    291 	return 0;
    292 }
    293 
    294 static struct vnd_softc *
    295 vnd_spawn(int unit)
    296 {
    297 	cfdata_t cf;
    298 
    299 	cf = malloc(sizeof(*cf), M_DEVBUF, M_WAITOK);
    300 	cf->cf_name = vnd_cd.cd_name;
    301 	cf->cf_atname = vnd_cd.cd_name;
    302 	cf->cf_unit = unit;
    303 	cf->cf_fstate = FSTATE_STAR;
    304 
    305 	return device_private(config_attach_pseudo(cf));
    306 }
    307 
    308 int
    309 vnd_destroy(device_t dev)
    310 {
    311 	int error;
    312 	cfdata_t cf;
    313 
    314 	cf = device_cfdata(dev);
    315 	error = config_detach(dev, DETACH_QUIET);
    316 	if (error)
    317 		return error;
    318 	free(cf, M_DEVBUF);
    319 	return 0;
    320 }
    321 
    322 static int
    323 vndopen(dev_t dev, int flags, int mode, struct lwp *l)
    324 {
    325 	int unit = vndunit(dev);
    326 	struct vnd_softc *sc;
    327 	int error = 0, part, pmask;
    328 	struct disklabel *lp;
    329 
    330 #ifdef DEBUG
    331 	if (vnddebug & VDB_FOLLOW)
    332 		printf("vndopen(0x%"PRIx64", 0x%x, 0x%x, %p)\n", dev, flags, mode, l);
    333 #endif
    334 	sc = device_lookup_private(&vnd_cd, unit);
    335 	if (sc == NULL) {
    336 		sc = vnd_spawn(unit);
    337 		if (sc == NULL)
    338 			return ENOMEM;
    339 
    340 		/* compatibility, keep disklabel after close */
    341 		sc->sc_flags = VNF_KLABEL;
    342 	}
    343 
    344 	if ((error = vndlock(sc)) != 0)
    345 		return error;
    346 
    347 	mutex_enter(&sc->sc_dkdev.dk_openlock);
    348 
    349 	if ((sc->sc_flags & VNF_CLEARING) != 0) {
    350 		error = ENXIO;
    351 		goto done;
    352 	}
    353 
    354 	lp = sc->sc_dkdev.dk_label;
    355 
    356 	part = DISKPART(dev);
    357 	pmask = (1 << part);
    358 
    359 	if (sc->sc_dkdev.dk_nwedges != 0 && part != RAW_PART) {
    360 		error = EBUSY;
    361 		goto done;
    362 	}
    363 
    364 	if (sc->sc_flags & VNF_INITED) {
    365 		if ((sc->sc_dkdev.dk_openmask & ~(1<<RAW_PART)) != 0) {
    366 			/*
    367 			 * If any non-raw partition is open, but the disk
    368 			 * has been invalidated, disallow further opens.
    369 			 */
    370 			if ((sc->sc_flags & VNF_VLABEL) == 0) {
    371 				error = EIO;
    372 				goto done;
    373 			}
    374 		} else {
    375 			/*
    376 			 * Load the partition info if not already loaded.
    377 			 */
    378 			if ((sc->sc_flags & VNF_VLABEL) == 0) {
    379 				sc->sc_flags |= VNF_VLABEL;
    380 				vndgetdisklabel(dev, sc);
    381 			}
    382 		}
    383 	}
    384 
    385 	/* Check that the partitions exists. */
    386 	if (part != RAW_PART) {
    387 		if (((sc->sc_flags & VNF_INITED) == 0) ||
    388 		    ((part >= lp->d_npartitions) ||
    389 		     (lp->d_partitions[part].p_fstype == FS_UNUSED))) {
    390 			error = ENXIO;
    391 			goto done;
    392 		}
    393 	}
    394 
    395 	/* Prevent our unit from being unconfigured while open. */
    396 	switch (mode) {
    397 	case S_IFCHR:
    398 		sc->sc_dkdev.dk_copenmask |= pmask;
    399 		break;
    400 
    401 	case S_IFBLK:
    402 		sc->sc_dkdev.dk_bopenmask |= pmask;
    403 		break;
    404 	}
    405 	sc->sc_dkdev.dk_openmask =
    406 	    sc->sc_dkdev.dk_copenmask | sc->sc_dkdev.dk_bopenmask;
    407 
    408  done:
    409 	mutex_exit(&sc->sc_dkdev.dk_openlock);
    410 	vndunlock(sc);
    411 	return error;
    412 }
    413 
    414 static int
    415 vndclose(dev_t dev, int flags, int mode, struct lwp *l)
    416 {
    417 	int unit = vndunit(dev);
    418 	struct vnd_softc *sc;
    419 	int error = 0, part;
    420 
    421 #ifdef DEBUG
    422 	if (vnddebug & VDB_FOLLOW)
    423 		printf("vndclose(0x%"PRIx64", 0x%x, 0x%x, %p)\n", dev, flags, mode, l);
    424 #endif
    425 	sc = device_lookup_private(&vnd_cd, unit);
    426 	if (sc == NULL)
    427 		return ENXIO;
    428 
    429 	if ((error = vndlock(sc)) != 0)
    430 		return error;
    431 
    432 	mutex_enter(&sc->sc_dkdev.dk_openlock);
    433 
    434 	part = DISKPART(dev);
    435 
    436 	/* ...that much closer to allowing unconfiguration... */
    437 	switch (mode) {
    438 	case S_IFCHR:
    439 		sc->sc_dkdev.dk_copenmask &= ~(1 << part);
    440 		break;
    441 
    442 	case S_IFBLK:
    443 		sc->sc_dkdev.dk_bopenmask &= ~(1 << part);
    444 		break;
    445 	}
    446 	sc->sc_dkdev.dk_openmask =
    447 	    sc->sc_dkdev.dk_copenmask | sc->sc_dkdev.dk_bopenmask;
    448 
    449 	/* are we last opener ? */
    450 	if (sc->sc_dkdev.dk_openmask == 0) {
    451 		if ((sc->sc_flags & VNF_KLABEL) == 0)
    452 			sc->sc_flags &= ~VNF_VLABEL;
    453 	}
    454 
    455 	mutex_exit(&sc->sc_dkdev.dk_openlock);
    456 
    457 	vndunlock(sc);
    458 
    459 	if ((sc->sc_flags & VNF_INITED) == 0) {
    460 		if ((error = vnd_destroy(sc->sc_dev)) != 0) {
    461 			aprint_error_dev(sc->sc_dev,
    462 			    "unable to detach instance\n");
    463 			return error;
    464 		}
    465 	}
    466 
    467 	return 0;
    468 }
    469 
    470 /*
    471  * Queue the request, and wakeup the kernel thread to handle it.
    472  */
    473 static void
    474 vndstrategy(struct buf *bp)
    475 {
    476 	int unit = vndunit(bp->b_dev);
    477 	struct vnd_softc *vnd =
    478 	    device_lookup_private(&vnd_cd, unit);
    479 	struct disklabel *lp;
    480 	daddr_t blkno;
    481 	int s = splbio();
    482 
    483 	if (vnd == NULL) {
    484 		bp->b_error = ENXIO;
    485 		goto done;
    486 	}
    487 	lp = vnd->sc_dkdev.dk_label;
    488 
    489 	if ((vnd->sc_flags & VNF_INITED) == 0) {
    490 		bp->b_error = ENXIO;
    491 		goto done;
    492 	}
    493 
    494 	/*
    495 	 * The transfer must be a whole number of blocks.
    496 	 */
    497 	if ((bp->b_bcount % lp->d_secsize) != 0) {
    498 		bp->b_error = EINVAL;
    499 		goto done;
    500 	}
    501 
    502 	/*
    503 	 * check if we're read-only.
    504 	 */
    505 	if ((vnd->sc_flags & VNF_READONLY) && !(bp->b_flags & B_READ)) {
    506 		bp->b_error = EACCES;
    507 		goto done;
    508 	}
    509 
    510 	/* If it's a nil transfer, wake up the top half now. */
    511 	if (bp->b_bcount == 0) {
    512 		goto done;
    513 	}
    514 
    515 	/*
    516 	 * Do bounds checking and adjust transfer.  If there's an error,
    517 	 * the bounds check will flag that for us.
    518 	 */
    519 	if (DISKPART(bp->b_dev) == RAW_PART) {
    520 		if (bounds_check_with_mediasize(bp, DEV_BSIZE,
    521 		    vnd->sc_size) <= 0)
    522 			goto done;
    523 	} else {
    524 		if (bounds_check_with_label(&vnd->sc_dkdev,
    525 		    bp, vnd->sc_flags & (VNF_WLABEL|VNF_LABELLING)) <= 0)
    526 			goto done;
    527 	}
    528 
    529 	/*
    530 	 * Put the block number in terms of the logical blocksize
    531 	 * of the "device".
    532 	 */
    533 
    534 	blkno = bp->b_blkno / (lp->d_secsize / DEV_BSIZE);
    535 
    536 	/*
    537 	 * Translate the partition-relative block number to an absolute.
    538 	 */
    539 	if (DISKPART(bp->b_dev) != RAW_PART) {
    540 		struct partition *pp;
    541 
    542 		pp = &vnd->sc_dkdev.dk_label->d_partitions[
    543 		    DISKPART(bp->b_dev)];
    544 		blkno += pp->p_offset;
    545 	}
    546 	bp->b_rawblkno = blkno;
    547 
    548 #ifdef DEBUG
    549 	if (vnddebug & VDB_FOLLOW)
    550 		printf("vndstrategy(%p): unit %d\n", bp, unit);
    551 #endif
    552 	if ((vnd->sc_flags & VNF_USE_VN_RDWR)) {
    553 		KASSERT(vnd->sc_pending >= 0 &&
    554 		    vnd->sc_pending <= VND_MAXPENDING(vnd));
    555 		while (vnd->sc_pending == VND_MAXPENDING(vnd))
    556 			tsleep(&vnd->sc_pending, PRIBIO, "vndpc", 0);
    557 		vnd->sc_pending++;
    558 	}
    559 	bufq_put(vnd->sc_tab, bp);
    560 	wakeup(&vnd->sc_tab);
    561 	splx(s);
    562 	return;
    563 
    564 done:
    565 	bp->b_resid = bp->b_bcount;
    566 	biodone(bp);
    567 	splx(s);
    568 }
    569 
    570 static bool
    571 vnode_has_strategy(struct vnd_softc *vnd)
    572 {
    573 	return vnode_has_op(vnd->sc_vp, VOFFSET(vop_bmap)) &&
    574 	    vnode_has_op(vnd->sc_vp, VOFFSET(vop_strategy));
    575 }
    576 
    577 /* Verify that I/O requests cannot be smaller than the
    578  * smallest I/O size supported by the backend.
    579  */
    580 static bool
    581 vnode_has_large_blocks(struct vnd_softc *vnd)
    582 {
    583 	u_int32_t vnd_secsize, iosize;
    584 
    585 	iosize = vnd->sc_iosize;
    586 	vnd_secsize = vnd->sc_geom.vng_secsize;
    587 
    588 	return vnd_secsize % iosize != 0;
    589 }
    590 
    591 /* XXX this function needs a reliable check to detect
    592  * sparse files. Otherwise, bmap/strategy may be used
    593  * and fail on non-allocated blocks. VOP_READ/VOP_WRITE
    594  * works on sparse files.
    595  */
    596 #if notyet
    597 static bool
    598 vnode_strategy_probe(struct vnd_softc *vnd)
    599 {
    600 	int error;
    601 	daddr_t nbn;
    602 
    603 	if (!vnode_has_strategy(vnd))
    604 		return false;
    605 
    606 	if (vnode_has_large_blocks(vnd))
    607 		return false;
    608 
    609 	/* Convert the first logical block number to its
    610 	 * physical block number.
    611 	 */
    612 	error = 0;
    613 	vn_lock(vnd->sc_vp, LK_EXCLUSIVE | LK_RETRY);
    614 	error = VOP_BMAP(vnd->sc_vp, 0, NULL, &nbn, NULL);
    615 	VOP_UNLOCK(vnd->sc_vp);
    616 
    617 	/* Test if that worked. */
    618 	if (error == 0 && (long)nbn == -1)
    619 		return false;
    620 
    621 	return true;
    622 }
    623 #endif
    624 
    625 static void
    626 vndthread(void *arg)
    627 {
    628 	struct vnd_softc *vnd = arg;
    629 	int s;
    630 
    631 	/* Determine whether we can *use* VOP_BMAP and VOP_STRATEGY to
    632 	 * directly access the backing vnode.  If we can, use these two
    633 	 * operations to avoid messing with the local buffer cache.
    634 	 * Otherwise fall back to regular VOP_READ/VOP_WRITE operations
    635 	 * which are guaranteed to work with any file system. */
    636 	if ((vnd->sc_flags & VNF_USE_VN_RDWR) == 0 &&
    637 	    ! vnode_has_strategy(vnd))
    638 		vnd->sc_flags |= VNF_USE_VN_RDWR;
    639 
    640 	/* VOP_STRATEGY can only be used if the backing vnode allows
    641 	 * to access blocks as small as defined by the vnd geometry.
    642 	 */
    643 	if ((vnd->sc_flags & VNF_USE_VN_RDWR) == 0 &&
    644 	    vnode_has_large_blocks(vnd))
    645 		vnd->sc_flags |= VNF_USE_VN_RDWR;
    646 
    647 #ifdef DEBUG
    648 	if (vnddebug & VDB_INIT)
    649 		printf("vndthread: vp %p, %s\n", vnd->sc_vp,
    650 		    (vnd->sc_flags & VNF_USE_VN_RDWR) == 0 ?
    651 		    "using bmap/strategy operations" :
    652 		    "using read/write operations");
    653 #endif
    654 
    655 	s = splbio();
    656 	vnd->sc_flags |= VNF_KTHREAD;
    657 	wakeup(&vnd->sc_kthread);
    658 
    659 	/*
    660 	 * Dequeue requests and serve them depending on the available
    661 	 * vnode operations.
    662 	 */
    663 	while ((vnd->sc_flags & VNF_VUNCONF) == 0) {
    664 		struct vndxfer *vnx;
    665 		struct buf *obp;
    666 		struct buf *bp;
    667 
    668 		obp = bufq_get(vnd->sc_tab);
    669 		if (obp == NULL) {
    670 			tsleep(&vnd->sc_tab, PRIBIO, "vndbp", 0);
    671 			continue;
    672 		};
    673 		if ((vnd->sc_flags & VNF_USE_VN_RDWR)) {
    674 			KASSERT(vnd->sc_pending > 0 &&
    675 			    vnd->sc_pending <= VND_MAXPENDING(vnd));
    676 			if (vnd->sc_pending-- == VND_MAXPENDING(vnd))
    677 				wakeup(&vnd->sc_pending);
    678 		}
    679 		splx(s);
    680 #ifdef DEBUG
    681 		if (vnddebug & VDB_FOLLOW)
    682 			printf("vndthread(%p)\n", obp);
    683 #endif
    684 
    685 		if (vnd->sc_vp->v_mount == NULL) {
    686 			obp->b_error = ENXIO;
    687 			goto done;
    688 		}
    689 #ifdef VND_COMPRESSION
    690 		/* handle a compressed read */
    691 		if ((obp->b_flags & B_READ) != 0 && (vnd->sc_flags & VNF_COMP)) {
    692 			off_t bn;
    693 
    694 			/* Convert to a byte offset within the file. */
    695 			bn = obp->b_rawblkno *
    696 			    vnd->sc_dkdev.dk_label->d_secsize;
    697 
    698 			compstrategy(obp, bn);
    699 			goto done;
    700 		}
    701 #endif /* VND_COMPRESSION */
    702 
    703 		/*
    704 		 * Allocate a header for this transfer and link it to the
    705 		 * buffer
    706 		 */
    707 		s = splbio();
    708 		vnx = VND_GETXFER(vnd);
    709 		splx(s);
    710 		vnx->vx_vnd = vnd;
    711 
    712 		s = splbio();
    713 		while (vnd->sc_active >= vnd->sc_maxactive) {
    714 			tsleep(&vnd->sc_tab, PRIBIO, "vndac", 0);
    715 		}
    716 		vnd->sc_active++;
    717 		splx(s);
    718 
    719 		/* Instrumentation. */
    720 		disk_busy(&vnd->sc_dkdev);
    721 
    722 		bp = &vnx->vx_buf;
    723 		buf_init(bp);
    724 		bp->b_flags = (obp->b_flags & B_READ);
    725 		bp->b_oflags = obp->b_oflags;
    726 		bp->b_cflags = obp->b_cflags;
    727 		bp->b_iodone = vndiodone;
    728 		bp->b_private = obp;
    729 		bp->b_vp = vnd->sc_vp;
    730 		bp->b_objlock = bp->b_vp->v_interlock;
    731 		bp->b_data = obp->b_data;
    732 		bp->b_bcount = obp->b_bcount;
    733 		BIO_COPYPRIO(bp, obp);
    734 
    735 		/* Handle the request using the appropriate operations. */
    736 		if ((vnd->sc_flags & VNF_USE_VN_RDWR) == 0)
    737 			handle_with_strategy(vnd, obp, bp);
    738 		else
    739 			handle_with_rdwr(vnd, obp, bp);
    740 
    741 		s = splbio();
    742 		continue;
    743 
    744 done:
    745 		biodone(obp);
    746 		s = splbio();
    747 	}
    748 
    749 	vnd->sc_flags &= (~VNF_KTHREAD | VNF_VUNCONF);
    750 	wakeup(&vnd->sc_kthread);
    751 	splx(s);
    752 	kthread_exit(0);
    753 }
    754 
    755 /*
    756  * Checks if the given vnode supports the requested operation.
    757  * The operation is specified the offset returned by VOFFSET.
    758  *
    759  * XXX The test below used to determine this is quite fragile
    760  * because it relies on the file system to use genfs to specify
    761  * unimplemented operations.  There might be another way to do
    762  * it more cleanly.
    763  */
    764 static bool
    765 vnode_has_op(const struct vnode *vp, int opoffset)
    766 {
    767 	int (*defaultp)(void *);
    768 	int (*opp)(void *);
    769 
    770 	defaultp = vp->v_op[VOFFSET(vop_default)];
    771 	opp = vp->v_op[opoffset];
    772 
    773 	return opp != defaultp && opp != genfs_eopnotsupp &&
    774 	    opp != genfs_badop && opp != genfs_nullop;
    775 }
    776 
    777 /*
    778  * Handles the read/write request given in 'bp' using the vnode's VOP_READ
    779  * and VOP_WRITE operations.
    780  *
    781  * 'obp' is a pointer to the original request fed to the vnd device.
    782  */
    783 static void
    784 handle_with_rdwr(struct vnd_softc *vnd, const struct buf *obp, struct buf *bp)
    785 {
    786 	bool doread;
    787 	off_t offset;
    788 	size_t len, resid;
    789 	struct vnode *vp;
    790 
    791 	doread = bp->b_flags & B_READ;
    792 	offset = obp->b_rawblkno * vnd->sc_dkdev.dk_label->d_secsize;
    793 	len = bp->b_bcount;
    794 	vp = vnd->sc_vp;
    795 
    796 #if defined(DEBUG)
    797 	if (vnddebug & VDB_IO)
    798 		printf("vnd (rdwr): vp %p, %s, rawblkno 0x%" PRIx64
    799 		    ", secsize %d, offset %" PRIu64
    800 		    ", bcount %d\n",
    801 		    vp, doread ? "read" : "write", obp->b_rawblkno,
    802 		    vnd->sc_dkdev.dk_label->d_secsize, offset,
    803 		    bp->b_bcount);
    804 #endif
    805 
    806 	/* Make sure the request succeeds while suspending this fs. */
    807 	fstrans_start_lazy(vp->v_mount);
    808 
    809 	/* Issue the read or write operation. */
    810 	bp->b_error =
    811 	    vn_rdwr(doread ? UIO_READ : UIO_WRITE,
    812 	    vp, bp->b_data, len, offset, UIO_SYSSPACE,
    813 	    IO_ADV_ENCODE(POSIX_FADV_NOREUSE), vnd->sc_cred, &resid, NULL);
    814 	bp->b_resid = resid;
    815 
    816 	mutex_enter(vp->v_interlock);
    817 	(void) VOP_PUTPAGES(vp, 0, 0,
    818 	    PGO_ALLPAGES | PGO_CLEANIT | PGO_FREE | PGO_SYNCIO);
    819 
    820 	fstrans_done(vp->v_mount);
    821 
    822 	/* We need to increase the number of outputs on the vnode if
    823 	 * there was any write to it. */
    824 	if (!doread) {
    825 		mutex_enter(vp->v_interlock);
    826 		vp->v_numoutput++;
    827 		mutex_exit(vp->v_interlock);
    828 	}
    829 
    830 	biodone(bp);
    831 }
    832 
    833 /*
    834  * Handes the read/write request given in 'bp' using the vnode's VOP_BMAP
    835  * and VOP_STRATEGY operations.
    836  *
    837  * 'obp' is a pointer to the original request fed to the vnd device.
    838  */
    839 static void
    840 handle_with_strategy(struct vnd_softc *vnd, const struct buf *obp,
    841     struct buf *bp)
    842 {
    843 	int bsize, error, flags, skipped;
    844 	size_t resid, sz;
    845 	off_t bn, offset;
    846 	struct vnode *vp;
    847 	struct buf *nbp = NULL;
    848 
    849 	flags = obp->b_flags;
    850 
    851 
    852 	/* convert to a byte offset within the file. */
    853 	bn = obp->b_rawblkno * vnd->sc_dkdev.dk_label->d_secsize;
    854 
    855 	bsize = vnd->sc_vp->v_mount->mnt_stat.f_iosize;
    856 	skipped = 0;
    857 
    858 	/*
    859 	 * Break the request into bsize pieces and feed them
    860 	 * sequentially using VOP_BMAP/VOP_STRATEGY.
    861 	 * We do it this way to keep from flooding NFS servers if we
    862 	 * are connected to an NFS file.  This places the burden on
    863 	 * the client rather than the server.
    864 	 */
    865 	error = 0;
    866 	bp->b_resid = bp->b_bcount;
    867 	for (offset = 0, resid = bp->b_resid; /* true */;
    868 	    resid -= sz, offset += sz) {
    869 		daddr_t nbn;
    870 		int off, nra;
    871 
    872 		nra = 0;
    873 		vn_lock(vnd->sc_vp, LK_EXCLUSIVE | LK_RETRY);
    874 		error = VOP_BMAP(vnd->sc_vp, bn / bsize, &vp, &nbn, &nra);
    875 		VOP_UNLOCK(vnd->sc_vp);
    876 
    877 		if (error == 0 && (long)nbn == -1)
    878 			error = EIO;
    879 
    880 		/*
    881 		 * If there was an error or a hole in the file...punt.
    882 		 * Note that we may have to wait for any operations
    883 		 * that we have already fired off before releasing
    884 		 * the buffer.
    885 		 *
    886 		 * XXX we could deal with holes here but it would be
    887 		 * a hassle (in the write case).
    888 		 */
    889 		if (error) {
    890 			skipped += resid;
    891 			break;
    892 		}
    893 
    894 #ifdef DEBUG
    895 		if (!dovndcluster)
    896 			nra = 0;
    897 #endif
    898 
    899 		off = bn % bsize;
    900 		sz = MIN(((off_t)1 + nra) * bsize - off, resid);
    901 #ifdef	DEBUG
    902 		if (vnddebug & VDB_IO)
    903 			printf("vndstrategy: vp %p/%p bn 0x%qx/0x%" PRIx64
    904 			    " sz 0x%zx\n", vnd->sc_vp, vp, (long long)bn,
    905 			    nbn, sz);
    906 #endif
    907 
    908 		nbp = getiobuf(vp, true);
    909 		nestiobuf_setup(bp, nbp, offset, sz);
    910 		nbp->b_blkno = nbn + btodb(off);
    911 
    912 #if 0 /* XXX #ifdef DEBUG */
    913 		if (vnddebug & VDB_IO)
    914 			printf("vndstart(%ld): bp %p vp %p blkno "
    915 			    "0x%" PRIx64 " flags %x addr %p cnt 0x%x\n",
    916 			    (long) (vnd-vnd_softc), &nbp->vb_buf,
    917 			    nbp->vb_buf.b_vp, nbp->vb_buf.b_blkno,
    918 			    nbp->vb_buf.b_flags, nbp->vb_buf.b_data,
    919 			    nbp->vb_buf.b_bcount);
    920 #endif
    921 		if (resid == sz) {
    922 			break;
    923 		}
    924 		VOP_STRATEGY(vp, nbp);
    925 		bn += sz;
    926 	}
    927 	if (!(flags & B_READ)) {
    928 		struct vnode *w_vp;
    929 		/*
    930 		 * this is the last nested buf, account for
    931 		 * the parent buf write too.
    932 		 * This has to be done last, so that
    933 		 * fsync won't wait for this write which
    934 		 * has no chance to complete before all nested bufs
    935 		 * have been queued. But it has to be done
    936 		 * before the last VOP_STRATEGY()
    937 		 * or the call to nestiobuf_done().
    938 		 */
    939 		w_vp = bp->b_vp;
    940 		mutex_enter(w_vp->v_interlock);
    941 		w_vp->v_numoutput++;
    942 		mutex_exit(w_vp->v_interlock);
    943 	}
    944 	KASSERT(skipped != 0 || nbp != NULL);
    945 	if (skipped)
    946 		nestiobuf_done(bp, skipped, error);
    947 	else
    948 		VOP_STRATEGY(vp, nbp);
    949 }
    950 
    951 static void
    952 vndiodone(struct buf *bp)
    953 {
    954 	struct vndxfer *vnx = VND_BUFTOXFER(bp);
    955 	struct vnd_softc *vnd = vnx->vx_vnd;
    956 	struct buf *obp = bp->b_private;
    957 	int s = splbio();
    958 
    959 	KASSERT(&vnx->vx_buf == bp);
    960 	KASSERT(vnd->sc_active > 0);
    961 #ifdef DEBUG
    962 	if (vnddebug & VDB_IO) {
    963 		printf("vndiodone1: bp %p iodone: error %d\n",
    964 		    bp, bp->b_error);
    965 	}
    966 #endif
    967 	disk_unbusy(&vnd->sc_dkdev, bp->b_bcount - bp->b_resid,
    968 	    (bp->b_flags & B_READ));
    969 	vnd->sc_active--;
    970 	if (vnd->sc_active == 0) {
    971 		wakeup(&vnd->sc_tab);
    972 	}
    973 	splx(s);
    974 	obp->b_error = bp->b_error;
    975 	obp->b_resid = bp->b_resid;
    976 	buf_destroy(bp);
    977 	VND_PUTXFER(vnd, vnx);
    978 	biodone(obp);
    979 }
    980 
    981 /* ARGSUSED */
    982 static int
    983 vndread(dev_t dev, struct uio *uio, int flags)
    984 {
    985 	int unit = vndunit(dev);
    986 	struct vnd_softc *sc;
    987 
    988 #ifdef DEBUG
    989 	if (vnddebug & VDB_FOLLOW)
    990 		printf("vndread(0x%"PRIx64", %p)\n", dev, uio);
    991 #endif
    992 
    993 	sc = device_lookup_private(&vnd_cd, unit);
    994 	if (sc == NULL)
    995 		return ENXIO;
    996 
    997 	if ((sc->sc_flags & VNF_INITED) == 0)
    998 		return ENXIO;
    999 
   1000 	return physio(vndstrategy, NULL, dev, B_READ, minphys, uio);
   1001 }
   1002 
   1003 /* ARGSUSED */
   1004 static int
   1005 vndwrite(dev_t dev, struct uio *uio, int flags)
   1006 {
   1007 	int unit = vndunit(dev);
   1008 	struct vnd_softc *sc;
   1009 
   1010 #ifdef DEBUG
   1011 	if (vnddebug & VDB_FOLLOW)
   1012 		printf("vndwrite(0x%"PRIx64", %p)\n", dev, uio);
   1013 #endif
   1014 
   1015 	sc = device_lookup_private(&vnd_cd, unit);
   1016 	if (sc == NULL)
   1017 		return ENXIO;
   1018 
   1019 	if ((sc->sc_flags & VNF_INITED) == 0)
   1020 		return ENXIO;
   1021 
   1022 	return physio(vndstrategy, NULL, dev, B_WRITE, minphys, uio);
   1023 }
   1024 
   1025 static int
   1026 vnd_cget(struct lwp *l, int unit, int *un, struct vattr *va)
   1027 {
   1028 	int error;
   1029 	struct vnd_softc *vnd;
   1030 
   1031 	if (*un == -1)
   1032 		*un = unit;
   1033 	if (*un < 0)
   1034 		return EINVAL;
   1035 
   1036 	vnd = device_lookup_private(&vnd_cd, *un);
   1037 	if (vnd == NULL)
   1038 		return -1;
   1039 
   1040 	if ((vnd->sc_flags & VNF_INITED) == 0)
   1041 		return -1;
   1042 
   1043 	vn_lock(vnd->sc_vp, LK_SHARED | LK_RETRY);
   1044 	error = VOP_GETATTR(vnd->sc_vp, va, l->l_cred);
   1045 	VOP_UNLOCK(vnd->sc_vp);
   1046 	return error;
   1047 }
   1048 
   1049 static int
   1050 vnddoclear(struct vnd_softc *vnd, int pmask, int minor, bool force)
   1051 {
   1052 	int error;
   1053 
   1054 	if ((error = vndlock(vnd)) != 0)
   1055 		return error;
   1056 
   1057 	/*
   1058 	 * Don't unconfigure if any other partitions are open
   1059 	 * or if both the character and block flavors of this
   1060 	 * partition are open.
   1061 	 */
   1062 	if (DK_BUSY(vnd, pmask) && !force) {
   1063 		vndunlock(vnd);
   1064 		return EBUSY;
   1065 	}
   1066 
   1067 	/* Delete all of our wedges */
   1068 	dkwedge_delall(&vnd->sc_dkdev);
   1069 
   1070 	/*
   1071 	 * XXX vndclear() might call vndclose() implicitly;
   1072 	 * release lock to avoid recursion
   1073 	 *
   1074 	 * Set VNF_CLEARING to prevent vndopen() from
   1075 	 * sneaking in after we vndunlock().
   1076 	 */
   1077 	vnd->sc_flags |= VNF_CLEARING;
   1078 	vndunlock(vnd);
   1079 	vndclear(vnd, minor);
   1080 #ifdef DEBUG
   1081 	if (vnddebug & VDB_INIT)
   1082 		printf("%s: CLRed\n", __func__);
   1083 #endif
   1084 
   1085 	/* Destroy the xfer and buffer pools. */
   1086 	pool_destroy(&vnd->sc_vxpool);
   1087 
   1088 	/* Detach the disk. */
   1089 	disk_detach(&vnd->sc_dkdev);
   1090 
   1091 	return 0;
   1092 }
   1093 
   1094 static int
   1095 vndioctl_get(struct lwp *l, void *data, int unit, struct vattr *va)
   1096 {
   1097 	int error;
   1098 
   1099 	KASSERT(l);
   1100 
   1101 	/* the first member is always int vnd_unit in all the versions */
   1102 	if (*(int *)data >= vnd_cd.cd_ndevs)
   1103 		return ENXIO;
   1104 
   1105 	switch (error = vnd_cget(l, unit, (int *)data, va)) {
   1106 	case -1:
   1107 		/* unused is not an error */
   1108 		memset(va, 0, sizeof(*va));
   1109 		/*FALLTHROUGH*/
   1110 	case 0:
   1111 		return 0;
   1112 	default:
   1113 		return error;
   1114 	}
   1115 }
   1116 
   1117 /* ARGSUSED */
   1118 static int
   1119 vndioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
   1120 {
   1121 	bool force;
   1122 	int unit = vndunit(dev);
   1123 	struct vnd_softc *vnd;
   1124 	struct vnd_ioctl *vio;
   1125 	struct vattr vattr;
   1126 	struct pathbuf *pb;
   1127 	struct nameidata nd;
   1128 	int error, part, pmask;
   1129 	uint64_t geomsize;
   1130 	int fflags;
   1131 #ifdef __HAVE_OLD_DISKLABEL
   1132 	struct disklabel newlabel;
   1133 #endif
   1134 
   1135 #ifdef DEBUG
   1136 	if (vnddebug & VDB_FOLLOW)
   1137 		printf("vndioctl(0x%"PRIx64", 0x%lx, %p, 0x%x, %p): unit %d\n",
   1138 		    dev, cmd, data, flag, l->l_proc, unit);
   1139 #endif
   1140 	/* Do the get's first; they don't need initialization or verification */
   1141 	switch (cmd) {
   1142 #ifdef COMPAT_30
   1143 	case VNDIOCGET30: {
   1144 		if ((error = vndioctl_get(l, data, unit, &vattr)) != 0)
   1145 			return error;
   1146 
   1147 		struct vnd_user30 *vnu = data;
   1148 		vnu->vnu_dev = vattr.va_fsid;
   1149 		vnu->vnu_ino = vattr.va_fileid;
   1150 		return 0;
   1151 	}
   1152 #endif
   1153 #ifdef COMPAT_50
   1154 	case VNDIOCGET50: {
   1155 		if ((error = vndioctl_get(l, data, unit, &vattr)) != 0)
   1156 			return error;
   1157 
   1158 		struct vnd_user50 *vnu = data;
   1159 		vnu->vnu_dev = vattr.va_fsid;
   1160 		vnu->vnu_ino = vattr.va_fileid;
   1161 		return 0;
   1162 	}
   1163 #endif
   1164 
   1165 	case VNDIOCGET: {
   1166 		if ((error = vndioctl_get(l, data, unit, &vattr)) != 0)
   1167 			return error;
   1168 
   1169 		struct vnd_user *vnu = data;
   1170 		vnu->vnu_dev = vattr.va_fsid;
   1171 		vnu->vnu_ino = vattr.va_fileid;
   1172 		return 0;
   1173 	}
   1174 	default:
   1175 		break;
   1176 	}
   1177 
   1178 	vnd = device_lookup_private(&vnd_cd, unit);
   1179 	if (vnd == NULL)
   1180 		return ENXIO;
   1181 	vio = (struct vnd_ioctl *)data;
   1182 
   1183 	/* Must be open for writes for these commands... */
   1184 	switch (cmd) {
   1185 	case VNDIOCSET:
   1186 	case VNDIOCCLR:
   1187 #ifdef COMPAT_50
   1188 	case VNDIOCSET50:
   1189 	case VNDIOCCLR50:
   1190 #endif
   1191 	case DIOCSDINFO:
   1192 	case DIOCWDINFO:
   1193 #ifdef __HAVE_OLD_DISKLABEL
   1194 	case ODIOCSDINFO:
   1195 	case ODIOCWDINFO:
   1196 #endif
   1197 	case DIOCKLABEL:
   1198 	case DIOCWLABEL:
   1199 		if ((flag & FWRITE) == 0)
   1200 			return EBADF;
   1201 	}
   1202 
   1203 	/* Must be initialized for these... */
   1204 	switch (cmd) {
   1205 	case VNDIOCCLR:
   1206 #ifdef VNDIOCCLR50
   1207 	case VNDIOCCLR50:
   1208 #endif
   1209 	case DIOCGDINFO:
   1210 	case DIOCSDINFO:
   1211 	case DIOCWDINFO:
   1212 	case DIOCGPARTINFO:
   1213 	case DIOCKLABEL:
   1214 	case DIOCWLABEL:
   1215 	case DIOCGDEFLABEL:
   1216 	case DIOCCACHESYNC:
   1217 #ifdef __HAVE_OLD_DISKLABEL
   1218 	case ODIOCGDINFO:
   1219 	case ODIOCSDINFO:
   1220 	case ODIOCWDINFO:
   1221 	case ODIOCGDEFLABEL:
   1222 #endif
   1223 		if ((vnd->sc_flags & VNF_INITED) == 0)
   1224 			return ENXIO;
   1225 	}
   1226 
   1227 	error = disk_ioctl(&vnd->sc_dkdev, dev, cmd, data, flag, l);
   1228 	if (error != EPASSTHROUGH)
   1229 		return error;
   1230 
   1231 
   1232 	switch (cmd) {
   1233 #ifdef VNDIOCSET50
   1234 	case VNDIOCSET50:
   1235 #endif
   1236 	case VNDIOCSET:
   1237 		if (vnd->sc_flags & VNF_INITED)
   1238 			return EBUSY;
   1239 
   1240 		if ((error = vndlock(vnd)) != 0)
   1241 			return error;
   1242 
   1243 		fflags = FREAD;
   1244 		if ((vio->vnd_flags & VNDIOF_READONLY) == 0)
   1245 			fflags |= FWRITE;
   1246 		if ((vio->vnd_flags & VNDIOF_FILEIO) != 0)
   1247 			vnd->sc_flags |= VNF_USE_VN_RDWR;
   1248 		error = pathbuf_copyin(vio->vnd_file, &pb);
   1249 		if (error) {
   1250 			goto unlock_and_exit;
   1251 		}
   1252 		NDINIT(&nd, LOOKUP, FOLLOW, pb);
   1253 		if ((error = vn_open(&nd, fflags, 0)) != 0) {
   1254 			pathbuf_destroy(pb);
   1255 			goto unlock_and_exit;
   1256 		}
   1257 		KASSERT(l);
   1258 		error = VOP_GETATTR(nd.ni_vp, &vattr, l->l_cred);
   1259 		if (!error && nd.ni_vp->v_type != VREG)
   1260 			error = EOPNOTSUPP;
   1261 		if (!error && vattr.va_bytes < vattr.va_size)
   1262 			/* File is definitely sparse, use vn_rdwr() */
   1263 			vnd->sc_flags |= VNF_USE_VN_RDWR;
   1264 		if (error) {
   1265 			VOP_UNLOCK(nd.ni_vp);
   1266 			goto close_and_exit;
   1267 		}
   1268 
   1269 		/* If using a compressed file, initialize its info */
   1270 		/* (or abort with an error if kernel has no compression) */
   1271 		if (vio->vnd_flags & VNDIOF_COMP) {
   1272 #ifdef VND_COMPRESSION
   1273 			struct vnd_comp_header *ch;
   1274 			int i;
   1275 			uint32_t comp_size;
   1276 			uint32_t comp_maxsize;
   1277 
   1278 			/* allocate space for compresed file header */
   1279 			ch = malloc(sizeof(struct vnd_comp_header),
   1280 			    M_TEMP, M_WAITOK);
   1281 
   1282 			/* read compressed file header */
   1283 			error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)ch,
   1284 			    sizeof(struct vnd_comp_header), 0, UIO_SYSSPACE,
   1285 			    IO_UNIT|IO_NODELOCKED, l->l_cred, NULL, NULL);
   1286 			if (error) {
   1287 				free(ch, M_TEMP);
   1288 				VOP_UNLOCK(nd.ni_vp);
   1289 				goto close_and_exit;
   1290 			}
   1291 
   1292 			if (be32toh(ch->block_size) == 0 ||
   1293 			    be32toh(ch->num_blocks) > UINT32_MAX - 1) {
   1294 				free(ch, M_TEMP);
   1295 				VOP_UNLOCK(nd.ni_vp);
   1296 				goto close_and_exit;
   1297 			}
   1298 
   1299 			/* save some header info */
   1300 			vnd->sc_comp_blksz = be32toh(ch->block_size);
   1301 			/* note last offset is the file byte size */
   1302 			vnd->sc_comp_numoffs = be32toh(ch->num_blocks) + 1;
   1303 			free(ch, M_TEMP);
   1304 			if (!DK_DEV_BSIZE_OK(vnd->sc_comp_blksz)) {
   1305 				VOP_UNLOCK(nd.ni_vp);
   1306 				error = EINVAL;
   1307 				goto close_and_exit;
   1308 			}
   1309 			KASSERT(0 < vnd->sc_comp_blksz);
   1310 			KASSERT(0 < vnd->sc_comp_numoffs);
   1311 			/*
   1312 			 * @#^@!$& gcc -Wtype-limits refuses to let me
   1313 			 * write SIZE_MAX/sizeof(uint64_t) < numoffs,
   1314 			 * because the range of the type on amd64 makes
   1315 			 * the comparisons always false.
   1316 			 */
   1317 #if SIZE_MAX <= UINT32_MAX*(64/CHAR_BIT)
   1318 			if (SIZE_MAX/sizeof(uint64_t) < vnd->sc_comp_numoffs) {
   1319 				VOP_UNLOCK(nd.ni_vp);
   1320 				error = EINVAL;
   1321 				goto close_and_exit;
   1322 			}
   1323 #endif
   1324 			if ((vattr.va_size < sizeof(struct vnd_comp_header)) ||
   1325 			    (vattr.va_size - sizeof(struct vnd_comp_header) <
   1326 				sizeof(uint64_t)*vnd->sc_comp_numoffs) ||
   1327 			    (UQUAD_MAX/vnd->sc_comp_blksz <
   1328 				vnd->sc_comp_numoffs - 1)) {
   1329 				VOP_UNLOCK(nd.ni_vp);
   1330 				error = EINVAL;
   1331 				goto close_and_exit;
   1332 			}
   1333 
   1334 			/* set decompressed file size */
   1335 			KASSERT(vnd->sc_comp_numoffs - 1 <=
   1336 			    UQUAD_MAX/vnd->sc_comp_blksz);
   1337 			vattr.va_size =
   1338 			    ((u_quad_t)vnd->sc_comp_numoffs - 1) *
   1339 			     (u_quad_t)vnd->sc_comp_blksz;
   1340 
   1341 			/* allocate space for all the compressed offsets */
   1342 			__CTASSERT(UINT32_MAX <= UQUAD_MAX/sizeof(uint64_t));
   1343 			vnd->sc_comp_offsets =
   1344 			    malloc(sizeof(uint64_t) * vnd->sc_comp_numoffs,
   1345 				M_DEVBUF, M_WAITOK);
   1346 
   1347 			/* read in the offsets */
   1348 			error = vn_rdwr(UIO_READ, nd.ni_vp,
   1349 			    (void *)vnd->sc_comp_offsets,
   1350 			    sizeof(uint64_t) * vnd->sc_comp_numoffs,
   1351 			    sizeof(struct vnd_comp_header), UIO_SYSSPACE,
   1352 			  IO_UNIT|IO_NODELOCKED, l->l_cred, NULL, NULL);
   1353 			if (error) {
   1354 				VOP_UNLOCK(nd.ni_vp);
   1355 				goto close_and_exit;
   1356 			}
   1357 			/*
   1358 			 * find largest block size (used for allocation limit).
   1359 			 * Also convert offset to native byte order.
   1360 			 */
   1361 			comp_maxsize = 0;
   1362 			for (i = 0; i < vnd->sc_comp_numoffs - 1; i++) {
   1363 				vnd->sc_comp_offsets[i] =
   1364 				    be64toh(vnd->sc_comp_offsets[i]);
   1365 				comp_size =
   1366 				    be64toh(vnd->sc_comp_offsets[i + 1])
   1367 				    - vnd->sc_comp_offsets[i];
   1368 				if (comp_size > comp_maxsize)
   1369 					comp_maxsize = comp_size;
   1370 			}
   1371 			vnd->sc_comp_offsets[vnd->sc_comp_numoffs - 1] =
   1372 			    be64toh(vnd->sc_comp_offsets[vnd->sc_comp_numoffs
   1373 				    - 1]);
   1374 
   1375 			/* create compressed data buffer */
   1376 			vnd->sc_comp_buff = malloc(comp_maxsize,
   1377 			    M_DEVBUF, M_WAITOK);
   1378 
   1379 			/* create decompressed buffer */
   1380 			vnd->sc_comp_decombuf = malloc(vnd->sc_comp_blksz,
   1381 			    M_DEVBUF, M_WAITOK);
   1382 			vnd->sc_comp_buffblk = -1;
   1383 
   1384 			/* Initialize decompress stream */
   1385 			memset(&vnd->sc_comp_stream, 0, sizeof(z_stream));
   1386 			vnd->sc_comp_stream.zalloc = vnd_alloc;
   1387 			vnd->sc_comp_stream.zfree = vnd_free;
   1388 			error = inflateInit2(&vnd->sc_comp_stream, MAX_WBITS);
   1389 			if (error) {
   1390 				if (vnd->sc_comp_stream.msg)
   1391 					printf("vnd%d: compressed file, %s\n",
   1392 					    unit, vnd->sc_comp_stream.msg);
   1393 				VOP_UNLOCK(nd.ni_vp);
   1394 				error = EINVAL;
   1395 				goto close_and_exit;
   1396 			}
   1397 
   1398 			vnd->sc_flags |= VNF_COMP | VNF_READONLY;
   1399 #else /* !VND_COMPRESSION */
   1400 			VOP_UNLOCK(nd.ni_vp);
   1401 			error = EOPNOTSUPP;
   1402 			goto close_and_exit;
   1403 #endif /* VND_COMPRESSION */
   1404 		}
   1405 
   1406 		VOP_UNLOCK(nd.ni_vp);
   1407 		vnd->sc_vp = nd.ni_vp;
   1408 		vnd->sc_size = btodb(vattr.va_size);	/* note truncation */
   1409 
   1410 		/* get smallest I/O size for underlying device, fall back to
   1411 		 * fundamental I/O size of underlying filesystem
   1412 		 */
   1413 		error = bdev_ioctl(vattr.va_fsid, DIOCGSECTORSIZE, &vnd->sc_iosize, FKIOCTL, l);
   1414 		if (error)
   1415 			vnd->sc_iosize = vnd->sc_vp->v_mount->mnt_stat.f_frsize;
   1416 
   1417 		/*
   1418 		 * Use pseudo-geometry specified.  If none was provided,
   1419 		 * use "standard" Adaptec fictitious geometry.
   1420 		 */
   1421 		if (vio->vnd_flags & VNDIOF_HASGEOM) {
   1422 
   1423 			memcpy(&vnd->sc_geom, &vio->vnd_geom,
   1424 			    sizeof(vio->vnd_geom));
   1425 
   1426 			/*
   1427 			 * Sanity-check the sector size.
   1428 			 */
   1429 			if (!DK_DEV_BSIZE_OK(vnd->sc_geom.vng_secsize) ||
   1430 			    vnd->sc_geom.vng_ncylinders == 0 ||
   1431 			    vnd->sc_geom.vng_ntracks == 0 ||
   1432 			    vnd->sc_geom.vng_nsectors == 0) {
   1433 				error = EINVAL;
   1434 				goto close_and_exit;
   1435 			}
   1436 
   1437 			/*
   1438 			 * Compute the size (in DEV_BSIZE blocks) specified
   1439 			 * by the geometry.
   1440 			 */
   1441 			geomsize = (int64_t)vnd->sc_geom.vng_nsectors *
   1442 			    vnd->sc_geom.vng_ntracks *
   1443 			    vnd->sc_geom.vng_ncylinders *
   1444 			    (vnd->sc_geom.vng_secsize / DEV_BSIZE);
   1445 
   1446 			/*
   1447 			 * Sanity-check the size against the specified
   1448 			 * geometry.
   1449 			 */
   1450 			if (vnd->sc_size < geomsize) {
   1451 				error = EINVAL;
   1452 				goto close_and_exit;
   1453 			}
   1454 		} else if (vnd->sc_size >= (32 * 64)) {
   1455 			/*
   1456 			 * Size must be at least 2048 DEV_BSIZE blocks
   1457 			 * (1M) in order to use this geometry.
   1458 			 */
   1459 			vnd->sc_geom.vng_secsize = DEV_BSIZE;
   1460 			vnd->sc_geom.vng_nsectors = 32;
   1461 			vnd->sc_geom.vng_ntracks = 64;
   1462 			vnd->sc_geom.vng_ncylinders = vnd->sc_size / (64 * 32);
   1463 		} else {
   1464 			vnd->sc_geom.vng_secsize = DEV_BSIZE;
   1465 			vnd->sc_geom.vng_nsectors = 1;
   1466 			vnd->sc_geom.vng_ntracks = 1;
   1467 			vnd->sc_geom.vng_ncylinders = vnd->sc_size;
   1468 		}
   1469 
   1470 		vnd_set_geometry(vnd);
   1471 
   1472 		if (vio->vnd_flags & VNDIOF_READONLY) {
   1473 			vnd->sc_flags |= VNF_READONLY;
   1474 		}
   1475 
   1476 		if ((error = vndsetcred(vnd, l->l_cred)) != 0)
   1477 			goto close_and_exit;
   1478 
   1479 		vndthrottle(vnd, vnd->sc_vp);
   1480 		vio->vnd_osize = dbtob(vnd->sc_size);
   1481 #ifdef VNDIOCSET50
   1482 		if (cmd != VNDIOCSET50)
   1483 #endif
   1484 			vio->vnd_size = dbtob(vnd->sc_size);
   1485 		vnd->sc_flags |= VNF_INITED;
   1486 
   1487 		/* create the kernel thread, wait for it to be up */
   1488 		error = kthread_create(PRI_NONE, 0, NULL, vndthread, vnd,
   1489 		    &vnd->sc_kthread, "%s", device_xname(vnd->sc_dev));
   1490 		if (error)
   1491 			goto close_and_exit;
   1492 		while ((vnd->sc_flags & VNF_KTHREAD) == 0) {
   1493 			tsleep(&vnd->sc_kthread, PRIBIO, "vndthr", 0);
   1494 		}
   1495 #ifdef DEBUG
   1496 		if (vnddebug & VDB_INIT)
   1497 			printf("vndioctl: SET vp %p size 0x%lx %d/%d/%d/%d\n",
   1498 			    vnd->sc_vp, (unsigned long) vnd->sc_size,
   1499 			    vnd->sc_geom.vng_secsize,
   1500 			    vnd->sc_geom.vng_nsectors,
   1501 			    vnd->sc_geom.vng_ntracks,
   1502 			    vnd->sc_geom.vng_ncylinders);
   1503 #endif
   1504 
   1505 		/* Attach the disk. */
   1506 		disk_attach(&vnd->sc_dkdev);
   1507 
   1508 		/* Initialize the xfer and buffer pools. */
   1509 		pool_init(&vnd->sc_vxpool, sizeof(struct vndxfer), 0,
   1510 		    0, 0, "vndxpl", NULL, IPL_BIO);
   1511 
   1512 		vndunlock(vnd);
   1513 
   1514 		pathbuf_destroy(pb);
   1515 
   1516 		/* Discover wedges on this disk */
   1517 		dkwedge_discover(&vnd->sc_dkdev);
   1518 
   1519 		break;
   1520 
   1521 close_and_exit:
   1522 		(void) vn_close(nd.ni_vp, fflags, l->l_cred);
   1523 		pathbuf_destroy(pb);
   1524 unlock_and_exit:
   1525 #ifdef VND_COMPRESSION
   1526 		/* free any allocated memory (for compressed file) */
   1527 		if (vnd->sc_comp_offsets) {
   1528 			free(vnd->sc_comp_offsets, M_DEVBUF);
   1529 			vnd->sc_comp_offsets = NULL;
   1530 		}
   1531 		if (vnd->sc_comp_buff) {
   1532 			free(vnd->sc_comp_buff, M_DEVBUF);
   1533 			vnd->sc_comp_buff = NULL;
   1534 		}
   1535 		if (vnd->sc_comp_decombuf) {
   1536 			free(vnd->sc_comp_decombuf, M_DEVBUF);
   1537 			vnd->sc_comp_decombuf = NULL;
   1538 		}
   1539 #endif /* VND_COMPRESSION */
   1540 		vndunlock(vnd);
   1541 		return error;
   1542 
   1543 #ifdef VNDIOCCLR50
   1544 	case VNDIOCCLR50:
   1545 #endif
   1546 	case VNDIOCCLR:
   1547 		part = DISKPART(dev);
   1548 		pmask = (1 << part);
   1549 		force = (vio->vnd_flags & VNDIOF_FORCE) != 0;
   1550 
   1551 		if ((error = vnddoclear(vnd, pmask, minor(dev), force)) != 0)
   1552 			return error;
   1553 
   1554 		break;
   1555 
   1556 
   1557 	case DIOCWDINFO:
   1558 	case DIOCSDINFO:
   1559 #ifdef __HAVE_OLD_DISKLABEL
   1560 	case ODIOCWDINFO:
   1561 	case ODIOCSDINFO:
   1562 #endif
   1563 	{
   1564 		struct disklabel *lp;
   1565 
   1566 		if ((error = vndlock(vnd)) != 0)
   1567 			return error;
   1568 
   1569 		vnd->sc_flags |= VNF_LABELLING;
   1570 
   1571 #ifdef __HAVE_OLD_DISKLABEL
   1572 		if (cmd == ODIOCSDINFO || cmd == ODIOCWDINFO) {
   1573 			memset(&newlabel, 0, sizeof newlabel);
   1574 			memcpy(&newlabel, data, sizeof (struct olddisklabel));
   1575 			lp = &newlabel;
   1576 		} else
   1577 #endif
   1578 		lp = (struct disklabel *)data;
   1579 
   1580 		error = setdisklabel(vnd->sc_dkdev.dk_label,
   1581 		    lp, 0, vnd->sc_dkdev.dk_cpulabel);
   1582 		if (error == 0) {
   1583 			if (cmd == DIOCWDINFO
   1584 #ifdef __HAVE_OLD_DISKLABEL
   1585 			    || cmd == ODIOCWDINFO
   1586 #endif
   1587 			   )
   1588 				error = writedisklabel(VNDLABELDEV(dev),
   1589 				    vndstrategy, vnd->sc_dkdev.dk_label,
   1590 				    vnd->sc_dkdev.dk_cpulabel);
   1591 		}
   1592 
   1593 		vnd->sc_flags &= ~VNF_LABELLING;
   1594 
   1595 		vndunlock(vnd);
   1596 
   1597 		if (error)
   1598 			return error;
   1599 		break;
   1600 	}
   1601 
   1602 	case DIOCKLABEL:
   1603 		if (*(int *)data != 0)
   1604 			vnd->sc_flags |= VNF_KLABEL;
   1605 		else
   1606 			vnd->sc_flags &= ~VNF_KLABEL;
   1607 		break;
   1608 
   1609 	case DIOCWLABEL:
   1610 		if (*(int *)data != 0)
   1611 			vnd->sc_flags |= VNF_WLABEL;
   1612 		else
   1613 			vnd->sc_flags &= ~VNF_WLABEL;
   1614 		break;
   1615 
   1616 	case DIOCGDEFLABEL:
   1617 		vndgetdefaultlabel(vnd, (struct disklabel *)data);
   1618 		break;
   1619 
   1620 #ifdef __HAVE_OLD_DISKLABEL
   1621 	case ODIOCGDEFLABEL:
   1622 		vndgetdefaultlabel(vnd, &newlabel);
   1623 		if (newlabel.d_npartitions > OLDMAXPARTITIONS)
   1624 			return ENOTTY;
   1625 		memcpy(data, &newlabel, sizeof (struct olddisklabel));
   1626 		break;
   1627 #endif
   1628 
   1629 	case DIOCCACHESYNC:
   1630 		vn_lock(vnd->sc_vp, LK_EXCLUSIVE | LK_RETRY);
   1631 		error = VOP_FSYNC(vnd->sc_vp, vnd->sc_cred,
   1632 		    FSYNC_WAIT | FSYNC_DATAONLY | FSYNC_CACHE, 0, 0);
   1633 		VOP_UNLOCK(vnd->sc_vp);
   1634 		return error;
   1635 
   1636 	default:
   1637 		return ENOTTY;
   1638 	}
   1639 
   1640 	return 0;
   1641 }
   1642 
   1643 /*
   1644  * Duplicate the current processes' credentials.  Since we are called only
   1645  * as the result of a SET ioctl and only root can do that, any future access
   1646  * to this "disk" is essentially as root.  Note that credentials may change
   1647  * if some other uid can write directly to the mapped file (NFS).
   1648  */
   1649 static int
   1650 vndsetcred(struct vnd_softc *vnd, kauth_cred_t cred)
   1651 {
   1652 	struct uio auio;
   1653 	struct iovec aiov;
   1654 	char *tmpbuf;
   1655 	int error;
   1656 
   1657 	vnd->sc_cred = kauth_cred_dup(cred);
   1658 	tmpbuf = malloc(DEV_BSIZE, M_TEMP, M_WAITOK);
   1659 
   1660 	/* XXX: Horrible kludge to establish credentials for NFS */
   1661 	aiov.iov_base = tmpbuf;
   1662 	aiov.iov_len = uimin(DEV_BSIZE, dbtob(vnd->sc_size));
   1663 	auio.uio_iov = &aiov;
   1664 	auio.uio_iovcnt = 1;
   1665 	auio.uio_offset = 0;
   1666 	auio.uio_rw = UIO_READ;
   1667 	auio.uio_resid = aiov.iov_len;
   1668 	UIO_SETUP_SYSSPACE(&auio);
   1669 	vn_lock(vnd->sc_vp, LK_EXCLUSIVE | LK_RETRY);
   1670 	error = VOP_READ(vnd->sc_vp, &auio, 0, vnd->sc_cred);
   1671 	if (error == 0) {
   1672 		/*
   1673 		 * Because vnd does all IO directly through the vnode
   1674 		 * we need to flush (at least) the buffer from the above
   1675 		 * VOP_READ from the buffer cache to prevent cache
   1676 		 * incoherencies.  Also, be careful to write dirty
   1677 		 * buffers back to stable storage.
   1678 		 */
   1679 		error = vinvalbuf(vnd->sc_vp, V_SAVE, vnd->sc_cred,
   1680 			    curlwp, 0, 0);
   1681 	}
   1682 	VOP_UNLOCK(vnd->sc_vp);
   1683 
   1684 	free(tmpbuf, M_TEMP);
   1685 	return error;
   1686 }
   1687 
   1688 /*
   1689  * Set maxactive based on FS type
   1690  */
   1691 static void
   1692 vndthrottle(struct vnd_softc *vnd, struct vnode *vp)
   1693 {
   1694 
   1695 	if (vp->v_tag == VT_NFS)
   1696 		vnd->sc_maxactive = 2;
   1697 	else
   1698 		vnd->sc_maxactive = 8;
   1699 
   1700 	if (vnd->sc_maxactive < 1)
   1701 		vnd->sc_maxactive = 1;
   1702 }
   1703 
   1704 #if 0
   1705 static void
   1706 vndshutdown(void)
   1707 {
   1708 	struct vnd_softc *vnd;
   1709 
   1710 	for (vnd = &vnd_softc[0]; vnd < &vnd_softc[numvnd]; vnd++)
   1711 		if (vnd->sc_flags & VNF_INITED)
   1712 			vndclear(vnd);
   1713 }
   1714 #endif
   1715 
   1716 static void
   1717 vndclear(struct vnd_softc *vnd, int myminor)
   1718 {
   1719 	struct vnode *vp = vnd->sc_vp;
   1720 	int fflags = FREAD;
   1721 	int bmaj, cmaj, i, mn;
   1722 	int s;
   1723 
   1724 #ifdef DEBUG
   1725 	if (vnddebug & VDB_FOLLOW)
   1726 		printf("vndclear(%p): vp %p\n", vnd, vp);
   1727 #endif
   1728 	/* locate the major number */
   1729 	bmaj = bdevsw_lookup_major(&vnd_bdevsw);
   1730 	cmaj = cdevsw_lookup_major(&vnd_cdevsw);
   1731 
   1732 	/* Nuke the vnodes for any open instances */
   1733 	for (i = 0; i < MAXPARTITIONS; i++) {
   1734 		mn = DISKMINOR(device_unit(vnd->sc_dev), i);
   1735 		vdevgone(bmaj, mn, mn, VBLK);
   1736 		if (mn != myminor) /* XXX avoid to kill own vnode */
   1737 			vdevgone(cmaj, mn, mn, VCHR);
   1738 	}
   1739 
   1740 	if ((vnd->sc_flags & VNF_READONLY) == 0)
   1741 		fflags |= FWRITE;
   1742 
   1743 	s = splbio();
   1744 	bufq_drain(vnd->sc_tab);
   1745 	splx(s);
   1746 
   1747 	vnd->sc_flags |= VNF_VUNCONF;
   1748 	wakeup(&vnd->sc_tab);
   1749 	while (vnd->sc_flags & VNF_KTHREAD)
   1750 		tsleep(&vnd->sc_kthread, PRIBIO, "vnthr", 0);
   1751 
   1752 #ifdef VND_COMPRESSION
   1753 	/* free the compressed file buffers */
   1754 	if (vnd->sc_flags & VNF_COMP) {
   1755 		if (vnd->sc_comp_offsets) {
   1756 			free(vnd->sc_comp_offsets, M_DEVBUF);
   1757 			vnd->sc_comp_offsets = NULL;
   1758 		}
   1759 		if (vnd->sc_comp_buff) {
   1760 			free(vnd->sc_comp_buff, M_DEVBUF);
   1761 			vnd->sc_comp_buff = NULL;
   1762 		}
   1763 		if (vnd->sc_comp_decombuf) {
   1764 			free(vnd->sc_comp_decombuf, M_DEVBUF);
   1765 			vnd->sc_comp_decombuf = NULL;
   1766 		}
   1767 	}
   1768 #endif /* VND_COMPRESSION */
   1769 	vnd->sc_flags &=
   1770 	    ~(VNF_INITED | VNF_READONLY | VNF_KLABEL | VNF_VLABEL
   1771 	      | VNF_VUNCONF | VNF_COMP | VNF_CLEARING);
   1772 	if (vp == NULL)
   1773 		panic("vndclear: null vp");
   1774 	(void) vn_close(vp, fflags, vnd->sc_cred);
   1775 	kauth_cred_free(vnd->sc_cred);
   1776 	vnd->sc_vp = NULL;
   1777 	vnd->sc_cred = NULL;
   1778 	vnd->sc_size = 0;
   1779 }
   1780 
   1781 static int
   1782 vndsize(dev_t dev)
   1783 {
   1784 	struct vnd_softc *sc;
   1785 	struct disklabel *lp;
   1786 	int part, unit, omask;
   1787 	int size;
   1788 
   1789 	unit = vndunit(dev);
   1790 	sc = device_lookup_private(&vnd_cd, unit);
   1791 	if (sc == NULL)
   1792 		return -1;
   1793 
   1794 	if ((sc->sc_flags & VNF_INITED) == 0)
   1795 		return -1;
   1796 
   1797 	part = DISKPART(dev);
   1798 	omask = sc->sc_dkdev.dk_openmask & (1 << part);
   1799 	lp = sc->sc_dkdev.dk_label;
   1800 
   1801 	if (omask == 0 && vndopen(dev, 0, S_IFBLK, curlwp))	/* XXX */
   1802 		return -1;
   1803 
   1804 	if (lp->d_partitions[part].p_fstype != FS_SWAP)
   1805 		size = -1;
   1806 	else
   1807 		size = lp->d_partitions[part].p_size *
   1808 		    (lp->d_secsize / DEV_BSIZE);
   1809 
   1810 	if (omask == 0 && vndclose(dev, 0, S_IFBLK, curlwp))	/* XXX */
   1811 		return -1;
   1812 
   1813 	return size;
   1814 }
   1815 
   1816 static int
   1817 vnddump(dev_t dev, daddr_t blkno, void *va,
   1818     size_t size)
   1819 {
   1820 
   1821 	/* Not implemented. */
   1822 	return ENXIO;
   1823 }
   1824 
   1825 static void
   1826 vndgetdefaultlabel(struct vnd_softc *sc, struct disklabel *lp)
   1827 {
   1828 	struct vndgeom *vng = &sc->sc_geom;
   1829 	struct partition *pp;
   1830 	unsigned spb;
   1831 
   1832 	memset(lp, 0, sizeof(*lp));
   1833 
   1834 	spb = vng->vng_secsize / DEV_BSIZE;
   1835 	if (sc->sc_size / spb > UINT32_MAX)
   1836 		lp->d_secperunit = UINT32_MAX;
   1837 	else
   1838 		lp->d_secperunit = sc->sc_size / spb;
   1839 	lp->d_secsize = vng->vng_secsize;
   1840 	lp->d_nsectors = vng->vng_nsectors;
   1841 	lp->d_ntracks = vng->vng_ntracks;
   1842 	lp->d_ncylinders = vng->vng_ncylinders;
   1843 	lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors;
   1844 
   1845 	strncpy(lp->d_typename, "vnd", sizeof(lp->d_typename));
   1846 	lp->d_type = DKTYPE_VND;
   1847 	strncpy(lp->d_packname, "fictitious", sizeof(lp->d_packname));
   1848 	lp->d_rpm = 3600;
   1849 	lp->d_interleave = 1;
   1850 	lp->d_flags = 0;
   1851 
   1852 	pp = &lp->d_partitions[RAW_PART];
   1853 	pp->p_offset = 0;
   1854 	pp->p_size = lp->d_secperunit;
   1855 	pp->p_fstype = FS_UNUSED;
   1856 	lp->d_npartitions = RAW_PART + 1;
   1857 
   1858 	lp->d_magic = DISKMAGIC;
   1859 	lp->d_magic2 = DISKMAGIC;
   1860 	lp->d_checksum = dkcksum(lp);
   1861 }
   1862 
   1863 /*
   1864  * Read the disklabel from a vnd.  If one is not present, create a fake one.
   1865  */
   1866 static void
   1867 vndgetdisklabel(dev_t dev, struct vnd_softc *sc)
   1868 {
   1869 	const char *errstring;
   1870 	struct disklabel *lp = sc->sc_dkdev.dk_label;
   1871 	struct cpu_disklabel *clp = sc->sc_dkdev.dk_cpulabel;
   1872 	int i;
   1873 
   1874 	memset(clp, 0, sizeof(*clp));
   1875 
   1876 	vndgetdefaultlabel(sc, lp);
   1877 
   1878 	/*
   1879 	 * Call the generic disklabel extraction routine.
   1880 	 */
   1881 	errstring = readdisklabel(VNDLABELDEV(dev), vndstrategy, lp, clp);
   1882 	if (errstring) {
   1883 		/*
   1884 		 * Lack of disklabel is common, but we print the warning
   1885 		 * anyway, since it might contain other useful information.
   1886 		 */
   1887 		aprint_normal_dev(sc->sc_dev, "%s\n", errstring);
   1888 
   1889 		/*
   1890 		 * For historical reasons, if there's no disklabel
   1891 		 * present, all partitions must be FS_BSDFFS and
   1892 		 * occupy the entire disk.
   1893 		 */
   1894 		for (i = 0; i < MAXPARTITIONS; i++) {
   1895 			/*
   1896 			 * Don't wipe out port specific hack (such as
   1897 			 * dos partition hack of i386 port).
   1898 			 */
   1899 			if (lp->d_partitions[i].p_size != 0)
   1900 				continue;
   1901 
   1902 			lp->d_partitions[i].p_size = lp->d_secperunit;
   1903 			lp->d_partitions[i].p_offset = 0;
   1904 			lp->d_partitions[i].p_fstype = FS_BSDFFS;
   1905 		}
   1906 
   1907 		strncpy(lp->d_packname, "default label",
   1908 		    sizeof(lp->d_packname));
   1909 
   1910 		lp->d_npartitions = MAXPARTITIONS;
   1911 		lp->d_checksum = dkcksum(lp);
   1912 	}
   1913 }
   1914 
   1915 /*
   1916  * Wait interruptibly for an exclusive lock.
   1917  *
   1918  * XXX
   1919  * Several drivers do this; it should be abstracted and made MP-safe.
   1920  */
   1921 static int
   1922 vndlock(struct vnd_softc *sc)
   1923 {
   1924 	int error;
   1925 
   1926 	while ((sc->sc_flags & VNF_LOCKED) != 0) {
   1927 		sc->sc_flags |= VNF_WANTED;
   1928 		if ((error = tsleep(sc, PRIBIO | PCATCH, "vndlck", 0)) != 0)
   1929 			return error;
   1930 	}
   1931 	sc->sc_flags |= VNF_LOCKED;
   1932 	return 0;
   1933 }
   1934 
   1935 /*
   1936  * Unlock and wake up any waiters.
   1937  */
   1938 static void
   1939 vndunlock(struct vnd_softc *sc)
   1940 {
   1941 
   1942 	sc->sc_flags &= ~VNF_LOCKED;
   1943 	if ((sc->sc_flags & VNF_WANTED) != 0) {
   1944 		sc->sc_flags &= ~VNF_WANTED;
   1945 		wakeup(sc);
   1946 	}
   1947 }
   1948 
   1949 #ifdef VND_COMPRESSION
   1950 /* compressed file read */
   1951 static void
   1952 compstrategy(struct buf *bp, off_t bn)
   1953 {
   1954 	int error;
   1955 	int unit = vndunit(bp->b_dev);
   1956 	struct vnd_softc *vnd =
   1957 	    device_lookup_private(&vnd_cd, unit);
   1958 	u_int32_t comp_block;
   1959 	struct uio auio;
   1960 	char *addr;
   1961 	int s;
   1962 
   1963 	/* set up constants for data move */
   1964 	auio.uio_rw = UIO_READ;
   1965 	UIO_SETUP_SYSSPACE(&auio);
   1966 
   1967 	/* read, and transfer the data */
   1968 	addr = bp->b_data;
   1969 	bp->b_resid = bp->b_bcount;
   1970 	s = splbio();
   1971 	while (bp->b_resid > 0) {
   1972 		unsigned length;
   1973 		size_t length_in_buffer;
   1974 		u_int32_t offset_in_buffer;
   1975 		struct iovec aiov;
   1976 
   1977 		/* calculate the compressed block number */
   1978 		comp_block = bn / (off_t)vnd->sc_comp_blksz;
   1979 
   1980 		/* check for good block number */
   1981 		if (comp_block >= vnd->sc_comp_numoffs) {
   1982 			bp->b_error = EINVAL;
   1983 			splx(s);
   1984 			return;
   1985 		}
   1986 
   1987 		/* read in the compressed block, if not in buffer */
   1988 		if (comp_block != vnd->sc_comp_buffblk) {
   1989 			length = vnd->sc_comp_offsets[comp_block + 1] -
   1990 			    vnd->sc_comp_offsets[comp_block];
   1991 			vn_lock(vnd->sc_vp, LK_EXCLUSIVE | LK_RETRY);
   1992 			error = vn_rdwr(UIO_READ, vnd->sc_vp, vnd->sc_comp_buff,
   1993 			    length, vnd->sc_comp_offsets[comp_block],
   1994 			    UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, vnd->sc_cred,
   1995 			    NULL, NULL);
   1996 			if (error) {
   1997 				bp->b_error = error;
   1998 				VOP_UNLOCK(vnd->sc_vp);
   1999 				splx(s);
   2000 				return;
   2001 			}
   2002 			/* uncompress the buffer */
   2003 			vnd->sc_comp_stream.next_in = vnd->sc_comp_buff;
   2004 			vnd->sc_comp_stream.avail_in = length;
   2005 			vnd->sc_comp_stream.next_out = vnd->sc_comp_decombuf;
   2006 			vnd->sc_comp_stream.avail_out = vnd->sc_comp_blksz;
   2007 			inflateReset(&vnd->sc_comp_stream);
   2008 			error = inflate(&vnd->sc_comp_stream, Z_FINISH);
   2009 			if (error != Z_STREAM_END) {
   2010 				if (vnd->sc_comp_stream.msg)
   2011 					aprint_normal_dev(vnd->sc_dev,
   2012 					    "compressed file, %s\n",
   2013 					    vnd->sc_comp_stream.msg);
   2014 				bp->b_error = EBADMSG;
   2015 				VOP_UNLOCK(vnd->sc_vp);
   2016 				splx(s);
   2017 				return;
   2018 			}
   2019 			vnd->sc_comp_buffblk = comp_block;
   2020 			VOP_UNLOCK(vnd->sc_vp);
   2021 		}
   2022 
   2023 		/* transfer the usable uncompressed data */
   2024 		offset_in_buffer = bn % (off_t)vnd->sc_comp_blksz;
   2025 		length_in_buffer = vnd->sc_comp_blksz - offset_in_buffer;
   2026 		if (length_in_buffer > bp->b_resid)
   2027 			length_in_buffer = bp->b_resid;
   2028 		auio.uio_iov = &aiov;
   2029 		auio.uio_iovcnt = 1;
   2030 		aiov.iov_base = addr;
   2031 		aiov.iov_len = length_in_buffer;
   2032 		auio.uio_resid = aiov.iov_len;
   2033 		auio.uio_offset = 0;
   2034 		error = uiomove(vnd->sc_comp_decombuf + offset_in_buffer,
   2035 		    length_in_buffer, &auio);
   2036 		if (error) {
   2037 			bp->b_error = error;
   2038 			splx(s);
   2039 			return;
   2040 		}
   2041 
   2042 		bn += length_in_buffer;
   2043 		addr += length_in_buffer;
   2044 		bp->b_resid -= length_in_buffer;
   2045 	}
   2046 	splx(s);
   2047 }
   2048 
   2049 /* compression memory allocation routines */
   2050 static void *
   2051 vnd_alloc(void *aux, u_int items, u_int siz)
   2052 {
   2053 	return malloc(items * siz, M_TEMP, M_NOWAIT);
   2054 }
   2055 
   2056 static void
   2057 vnd_free(void *aux, void *ptr)
   2058 {
   2059 	free(ptr, M_TEMP);
   2060 }
   2061 #endif /* VND_COMPRESSION */
   2062 
   2063 static void
   2064 vnd_set_geometry(struct vnd_softc *vnd)
   2065 {
   2066 	struct disk_geom *dg = &vnd->sc_dkdev.dk_geom;
   2067 
   2068 	memset(dg, 0, sizeof(*dg));
   2069 
   2070 	dg->dg_secperunit = (int64_t)vnd->sc_geom.vng_nsectors *
   2071 	    vnd->sc_geom.vng_ntracks * vnd->sc_geom.vng_ncylinders;
   2072 	dg->dg_secsize = vnd->sc_geom.vng_secsize;
   2073 	dg->dg_nsectors = vnd->sc_geom.vng_nsectors;
   2074 	dg->dg_ntracks = vnd->sc_geom.vng_ntracks;
   2075 	dg->dg_ncylinders = vnd->sc_geom.vng_ncylinders;
   2076 
   2077 #ifdef DEBUG
   2078 	if (vnddebug & VDB_LABEL) {
   2079 		printf("dg->dg_secperunit: %" PRId64 "\n", dg->dg_secperunit);
   2080 		printf("dg->dg_ncylinders: %u\n", dg->dg_ncylinders);
   2081 	}
   2082 #endif
   2083 	disk_set_info(vnd->sc_dev, &vnd->sc_dkdev, NULL);
   2084 }
   2085 
   2086 #ifdef VND_COMPRESSION
   2087 #define VND_DEPENDS "zlib"
   2088 #else
   2089 #define VND_DEPENDS NULL
   2090 #endif
   2091 
   2092 MODULE(MODULE_CLASS_DRIVER, vnd, VND_DEPENDS);
   2093 
   2094 #ifdef _MODULE
   2095 int vnd_bmajor = -1, vnd_cmajor = -1;
   2096 
   2097 CFDRIVER_DECL(vnd, DV_DISK, NULL);
   2098 #endif
   2099 
   2100 static int
   2101 vnd_modcmd(modcmd_t cmd, void *arg)
   2102 {
   2103 	int error = 0;
   2104 
   2105 	switch (cmd) {
   2106 	case MODULE_CMD_INIT:
   2107 #ifdef _MODULE
   2108 		error = config_cfdriver_attach(&vnd_cd);
   2109 		if (error)
   2110 			break;
   2111 
   2112 		error = config_cfattach_attach(vnd_cd.cd_name, &vnd_ca);
   2113 	        if (error) {
   2114 			config_cfdriver_detach(&vnd_cd);
   2115 #ifdef DIAGNOSTIC
   2116 			aprint_error("%s: unable to register cfattach for \n"
   2117 			    "%s, error %d", __func__, vnd_cd.cd_name, error);
   2118 #endif
   2119 			break;
   2120 		}
   2121 
   2122                 /*
   2123                  * Attach the {b,c}devsw's
   2124                  */
   2125 		error = devsw_attach("vnd", &vnd_bdevsw, &vnd_bmajor,
   2126 		    &vnd_cdevsw, &vnd_cmajor);
   2127                 /*
   2128                  * If devsw_attach fails, remove from autoconf database
   2129                  */
   2130 		if (error) {
   2131 			config_cfattach_detach(vnd_cd.cd_name, &vnd_ca);
   2132 			config_cfdriver_detach(&vnd_cd);
   2133 #ifdef DIAGNOSTIC
   2134                         aprint_error("%s: unable to attach %s devsw, "
   2135                             "error %d", __func__, vnd_cd.cd_name, error);
   2136 #endif
   2137 			break;
   2138 		}
   2139 #endif
   2140 		break;
   2141 
   2142 	case MODULE_CMD_FINI:
   2143 #ifdef _MODULE
   2144                 /*
   2145                  * Remove {b,c}devsw's
   2146                  */
   2147 		devsw_detach(&vnd_bdevsw, &vnd_cdevsw);
   2148 
   2149                 /*
   2150                  * Now remove device from autoconf database
   2151                  */
   2152 		error = config_cfattach_detach(vnd_cd.cd_name, &vnd_ca);
   2153                 if (error) {
   2154                         (void)devsw_attach("vnd", &vnd_bdevsw, &vnd_bmajor,
   2155                             &vnd_cdevsw, &vnd_cmajor);
   2156 #ifdef DIAGNOSTIC
   2157                         aprint_error("%s: failed to detach %s cfattach, "
   2158                             "error %d\n", __func__, vnd_cd.cd_name, error);
   2159 #endif
   2160                         break;
   2161                 }
   2162                 error = config_cfdriver_detach(&vnd_cd);
   2163                 if (error) {
   2164                         (void)config_cfattach_attach(vnd_cd.cd_name, &vnd_ca);
   2165                         (void)devsw_attach("vnd", &vnd_bdevsw, &vnd_bmajor,
   2166                             &vnd_cdevsw, &vnd_cmajor);
   2167 #ifdef DIAGNOSTIC
   2168                         aprint_error("%s: failed to detach %s cfdriver, "
   2169                             "error %d\n", __func__, vnd_cd.cd_name, error);
   2170                         break;
   2171 #endif
   2172                 }
   2173 #endif
   2174 		break;
   2175 
   2176 	case MODULE_CMD_STAT:
   2177 		return ENOTTY;
   2178 
   2179 	default:
   2180 		return ENOTTY;
   2181 	}
   2182 
   2183 	return error;
   2184 }
   2185