vnd.c revision 1.92
1/*	$NetBSD: vnd.c,v 1.92 2003/02/25 20:35:34 thorpej 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) 1988 University of Utah.
41 * Copyright (c) 1990, 1993
42 *	The Regents of the University of California.  All rights reserved.
43 *
44 * This code is derived from software contributed to Berkeley by
45 * the Systems Programming Group of the University of Utah Computer
46 * Science Department.
47 *
48 * Redistribution and use in source and binary forms, with or without
49 * modification, are permitted provided that the following conditions
50 * are met:
51 * 1. Redistributions of source code must retain the above copyright
52 *    notice, this list of conditions and the following disclaimer.
53 * 2. Redistributions in binary form must reproduce the above copyright
54 *    notice, this list of conditions and the following disclaimer in the
55 *    documentation and/or other materials provided with the distribution.
56 * 3. All advertising materials mentioning features or use of this software
57 *    must display the following acknowledgement:
58 *	This product includes software developed by the University of
59 *	California, Berkeley and its contributors.
60 * 4. Neither the name of the University nor the names of its contributors
61 *    may be used to endorse or promote products derived from this software
62 *    without specific prior written permission.
63 *
64 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
65 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
66 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
67 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
68 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
69 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
70 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
71 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
72 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
73 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
74 * SUCH DAMAGE.
75 *
76 * from: Utah $Hdr: vn.c 1.13 94/04/02$
77 *
78 *	@(#)vn.c	8.9 (Berkeley) 5/14/95
79 */
80
81/*
82 * Vnode disk driver.
83 *
84 * Block/character interface to a vnode.  Allows one to treat a file
85 * as a disk (e.g. build a filesystem in it, mount it, etc.).
86 *
87 * NOTE 1: This uses the VOP_BMAP/VOP_STRATEGY interface to the vnode
88 * instead of a simple VOP_RDWR.  We do this to avoid distorting the
89 * local buffer cache.
90 *
91 * NOTE 2: There is a security issue involved with this driver.
92 * Once mounted all access to the contents of the "mapped" file via
93 * the special file is controlled by the permissions on the special
94 * file, the protection of the mapped file is ignored (effectively,
95 * by using root credentials in all transactions).
96 *
97 * NOTE 3: Doesn't interact with leases, should it?
98 */
99
100#include <sys/cdefs.h>
101__KERNEL_RCSID(0, "$NetBSD: vnd.c,v 1.92 2003/02/25 20:35:34 thorpej Exp $");
102
103#if defined(_KERNEL_OPT)
104#include "fs_nfs.h"
105#endif
106
107#include <sys/param.h>
108#include <sys/systm.h>
109#include <sys/namei.h>
110#include <sys/proc.h>
111#include <sys/errno.h>
112#include <sys/buf.h>
113#include <sys/malloc.h>
114#include <sys/ioctl.h>
115#include <sys/disklabel.h>
116#include <sys/device.h>
117#include <sys/disk.h>
118#include <sys/stat.h>
119#include <sys/mount.h>
120#include <sys/vnode.h>
121#include <sys/file.h>
122#include <sys/uio.h>
123#include <sys/conf.h>
124
125#include <miscfs/specfs/specdev.h>
126
127#include <dev/vndvar.h>
128
129#if defined(VNDDEBUG) && !defined(DEBUG)
130#define	DEBUG
131#endif
132
133#ifdef DEBUG
134int dovndcluster = 1;
135#define	VDB_FOLLOW	0x01
136#define	VDB_INIT	0x02
137#define	VDB_IO		0x04
138#define	VDB_LABEL	0x08
139int vnddebug = 0x00;
140#endif
141
142#define	vndunit(x)	DISKUNIT(x)
143
144struct vndxfer {
145	struct buf	*vx_bp;		/* Pointer to parent buffer */
146	int		vx_error;
147	int		vx_pending;	/* # of pending aux buffers */
148	int		vx_flags;
149#define VX_BUSY		1
150};
151
152struct vndbuf {
153	struct buf	vb_buf;
154	struct vndxfer	*vb_xfer;
155};
156
157#define	VND_GETXFER(vnd)	pool_get(&(vnd)->sc_vxpool, PR_NOWAIT)
158#define	VND_PUTXFER(vnd, vx)	pool_put(&(vnd)->sc_vxpool, (vx))
159
160#define	VND_GETBUF(vnd)		pool_get(&(vnd)->sc_vbpool, PR_NOWAIT)
161#define	VND_PUTBUF(vnd, vb)	pool_put(&(vnd)->sc_vbpool, (vb))
162
163struct vnd_softc *vnd_softc;
164int numvnd = 0;
165
166#define	VNDLABELDEV(dev) \
167	(MAKEDISKDEV(major((dev)), vndunit((dev)), RAW_PART))
168
169/* called by main() at boot time (XXX: and the LKM driver) */
170void	vndattach __P((int));
171int	vnddetach __P((void));
172
173void	vndclear __P((struct vnd_softc *));
174void	vndstart __P((struct vnd_softc *));
175int	vndsetcred __P((struct vnd_softc *, struct ucred *));
176void	vndthrottle __P((struct vnd_softc *, struct vnode *));
177void	vndiodone __P((struct buf *));
178void	vndshutdown __P((void));
179
180void	vndgetdefaultlabel __P((struct vnd_softc *, struct disklabel *));
181void	vndgetdisklabel __P((dev_t));
182
183static	int vndlock __P((struct vnd_softc *));
184static	void vndunlock __P((struct vnd_softc *));
185
186dev_type_open(vndopen);
187dev_type_close(vndclose);
188dev_type_read(vndread);
189dev_type_write(vndwrite);
190dev_type_ioctl(vndioctl);
191dev_type_strategy(vndstrategy);
192dev_type_dump(vnddump);
193dev_type_size(vndsize);
194
195const struct bdevsw vnd_bdevsw = {
196	vndopen, vndclose, vndstrategy, vndioctl, vnddump, vndsize, D_DISK
197};
198
199const struct cdevsw vnd_cdevsw = {
200	vndopen, vndclose, vndread, vndwrite, vndioctl,
201	nostop, notty, nopoll, nommap, nokqfilter, D_DISK
202};
203
204int vndattached = 0;
205
206void
207vndattach(num)
208	int num;
209{
210	int i;
211	char *mem;
212
213	if (vndattached)
214		return;
215	vndattached = 1;
216	if (num <= 0)
217		return;
218	i = num * sizeof(struct vnd_softc);
219	mem = malloc(i, M_DEVBUF, M_NOWAIT|M_ZERO);
220	if (mem == NULL) {
221		printf("WARNING: no memory for vnode disks\n");
222		return;
223	}
224	vnd_softc = (struct vnd_softc *)mem;
225	numvnd = num;
226
227	for (i = 0; i < numvnd; i++)
228		bufq_alloc(&vnd_softc[i].sc_tab,
229		    BUFQ_DISKSORT|BUFQ_SORT_RAWBLOCK);
230}
231
232int
233vnddetach()
234{
235	int i;
236
237	/* First check we aren't in use. */
238	for (i = 0; i < numvnd; i++)
239		if (vnd_softc[i].sc_flags & VNF_INITED)
240			return (EBUSY);
241
242	for (i = 0; i < numvnd; i++)
243		bufq_free(&vnd_softc[i].sc_tab);
244
245	free(vnd_softc, M_DEVBUF);
246	vndattached = 0;
247
248	return (0);
249}
250
251int
252vndopen(dev, flags, mode, p)
253	dev_t dev;
254	int flags, mode;
255	struct proc *p;
256{
257	int unit = vndunit(dev);
258	struct vnd_softc *sc;
259	int error = 0, part, pmask;
260	struct disklabel *lp;
261
262#ifdef DEBUG
263	if (vnddebug & VDB_FOLLOW)
264		printf("vndopen(0x%x, 0x%x, 0x%x, %p)\n", dev, flags, mode, p);
265#endif
266	if (unit >= numvnd)
267		return (ENXIO);
268	sc = &vnd_softc[unit];
269
270	if ((error = vndlock(sc)) != 0)
271		return (error);
272
273	lp = sc->sc_dkdev.dk_label;
274
275	part = DISKPART(dev);
276	pmask = (1 << part);
277
278	/*
279	 * If we're initialized, check to see if there are any other
280	 * open partitions.  If not, then it's safe to update the
281	 * in-core disklabel.
282	 */
283	if ((sc->sc_flags & VNF_INITED) && (sc->sc_dkdev.dk_openmask == 0))
284		vndgetdisklabel(dev);
285
286	/* Check that the partitions exists. */
287	if (part != RAW_PART) {
288		if (((sc->sc_flags & VNF_INITED) == 0) ||
289		    ((part >= lp->d_npartitions) ||
290		     (lp->d_partitions[part].p_fstype == FS_UNUSED))) {
291			error = ENXIO;
292			goto done;
293		}
294	}
295
296	/* Prevent our unit from being unconfigured while open. */
297	switch (mode) {
298	case S_IFCHR:
299		sc->sc_dkdev.dk_copenmask |= pmask;
300		break;
301
302	case S_IFBLK:
303		sc->sc_dkdev.dk_bopenmask |= pmask;
304		break;
305	}
306	sc->sc_dkdev.dk_openmask =
307	    sc->sc_dkdev.dk_copenmask | sc->sc_dkdev.dk_bopenmask;
308
309 done:
310	vndunlock(sc);
311	return (error);
312}
313
314int
315vndclose(dev, flags, mode, p)
316	dev_t dev;
317	int flags, mode;
318	struct proc *p;
319{
320	int unit = vndunit(dev);
321	struct vnd_softc *sc;
322	int error = 0, part;
323
324#ifdef DEBUG
325	if (vnddebug & VDB_FOLLOW)
326		printf("vndclose(0x%x, 0x%x, 0x%x, %p)\n", dev, flags, mode, p);
327#endif
328
329	if (unit >= numvnd)
330		return (ENXIO);
331	sc = &vnd_softc[unit];
332
333	if ((error = vndlock(sc)) != 0)
334		return (error);
335
336	part = DISKPART(dev);
337
338	/* ...that much closer to allowing unconfiguration... */
339	switch (mode) {
340	case S_IFCHR:
341		sc->sc_dkdev.dk_copenmask &= ~(1 << part);
342		break;
343
344	case S_IFBLK:
345		sc->sc_dkdev.dk_bopenmask &= ~(1 << part);
346		break;
347	}
348	sc->sc_dkdev.dk_openmask =
349	    sc->sc_dkdev.dk_copenmask | sc->sc_dkdev.dk_bopenmask;
350
351	vndunlock(sc);
352	return (0);
353}
354
355/*
356 * Break the request into bsize pieces and submit using VOP_BMAP/VOP_STRATEGY.
357 */
358void
359vndstrategy(bp)
360	struct buf *bp;
361{
362	int unit = vndunit(bp->b_dev);
363	struct vnd_softc *vnd = &vnd_softc[unit];
364	struct vndxfer *vnx;
365	int s, bsize, resid;
366	off_t bn;
367	caddr_t addr;
368	int sz, flags, error, wlabel;
369	struct disklabel *lp;
370	struct partition *pp;
371
372#ifdef DEBUG
373	if (vnddebug & VDB_FOLLOW)
374		printf("vndstrategy(%p): unit %d\n", bp, unit);
375#endif
376	if ((vnd->sc_flags & VNF_INITED) == 0) {
377		bp->b_error = ENXIO;
378		bp->b_flags |= B_ERROR;
379		goto done;
380	}
381
382	/* If it's a nil transfer, wake up the top half now. */
383	if (bp->b_bcount == 0)
384		goto done;
385
386	lp = vnd->sc_dkdev.dk_label;
387
388	/*
389	 * The transfer must be a whole number of blocks.
390	 */
391	if ((bp->b_bcount % lp->d_secsize) != 0) {
392		bp->b_error = EINVAL;
393		bp->b_flags |= B_ERROR;
394		goto done;
395	}
396
397	/*
398	 * Do bounds checking and adjust transfer.  If there's an error,
399	 * the bounds check will flag that for us.
400	 */
401	wlabel = vnd->sc_flags & (VNF_WLABEL|VNF_LABELLING);
402	if (DISKPART(bp->b_dev) != RAW_PART)
403		if (bounds_check_with_label(bp, lp, wlabel) <= 0)
404			goto done;
405
406	bp->b_resid = bp->b_bcount;
407
408	/*
409	 * Put the block number in terms of the logical blocksize
410	 * of the "device".
411	 */
412	bn = bp->b_blkno / (lp->d_secsize / DEV_BSIZE);
413
414	/*
415	 * Translate the partition-relative block number to an absolute.
416	 */
417	if (DISKPART(bp->b_dev) != RAW_PART) {
418		pp = &vnd->sc_dkdev.dk_label->d_partitions[DISKPART(bp->b_dev)];
419		bn += pp->p_offset;
420	}
421
422	/* ...and convert to a byte offset within the file. */
423	bn *= lp->d_secsize;
424
425	if (vnd->sc_vp->v_mount == NULL) {
426		bp->b_error = ENXIO;
427		bp->b_flags |= B_ERROR;
428		goto done;
429	}
430 	bsize = vnd->sc_vp->v_mount->mnt_stat.f_iosize;
431	addr = bp->b_data;
432	flags = (bp->b_flags & (B_READ|B_ASYNC)) | B_CALL;
433
434	/* Allocate a header for this transfer and link it to the buffer */
435	s = splbio();
436	vnx = VND_GETXFER(vnd);
437	splx(s);
438	vnx->vx_flags = VX_BUSY;
439	vnx->vx_error = 0;
440	vnx->vx_pending = 0;
441	vnx->vx_bp = bp;
442
443	for (resid = bp->b_resid; resid; resid -= sz) {
444		struct vndbuf *nbp;
445		struct vnode *vp;
446		daddr_t nbn;
447		int off, nra;
448
449		nra = 0;
450		vn_lock(vnd->sc_vp, LK_EXCLUSIVE | LK_RETRY | LK_CANRECURSE);
451		error = VOP_BMAP(vnd->sc_vp, bn / bsize, &vp, &nbn, &nra);
452		VOP_UNLOCK(vnd->sc_vp, 0);
453
454		if (error == 0 && (long)nbn == -1)
455			error = EIO;
456
457		/*
458		 * If there was an error or a hole in the file...punt.
459		 * Note that we may have to wait for any operations
460		 * that we have already fired off before releasing
461		 * the buffer.
462		 *
463		 * XXX we could deal with holes here but it would be
464		 * a hassle (in the write case).
465		 */
466		if (error) {
467			s = splbio();
468			vnx->vx_error = error;
469			goto out;
470		}
471
472#ifdef DEBUG
473		if (!dovndcluster)
474			nra = 0;
475#endif
476
477		if ((off = bn % bsize) != 0)
478			sz = bsize - off;
479		else
480			sz = (1 + nra) * bsize;
481		if (resid < sz)
482			sz = resid;
483#ifdef DEBUG
484		if (vnddebug & VDB_IO)
485			printf("vndstrategy: vp %p/%p bn 0x%qx/0x%" PRIx64
486			       " sz 0x%x\n",
487			    vnd->sc_vp, vp, (long long)bn, nbn, sz);
488#endif
489
490		s = splbio();
491		nbp = VND_GETBUF(vnd);
492		splx(s);
493		BUF_INIT(&nbp->vb_buf);
494		nbp->vb_buf.b_flags = flags;
495		nbp->vb_buf.b_bcount = sz;
496		nbp->vb_buf.b_bufsize = round_page((ulong)addr + sz)
497		    - trunc_page((ulong) addr);
498		nbp->vb_buf.b_error = 0;
499		nbp->vb_buf.b_data = addr;
500		nbp->vb_buf.b_blkno = nbp->vb_buf.b_rawblkno = nbn + btodb(off);
501		nbp->vb_buf.b_proc = bp->b_proc;
502		nbp->vb_buf.b_iodone = vndiodone;
503		nbp->vb_buf.b_vp = NULLVP;
504
505		nbp->vb_xfer = vnx;
506
507		/*
508		 * Just sort by block number
509		 */
510		s = splbio();
511		if (vnx->vx_error != 0) {
512			VND_PUTBUF(vnd, nbp);
513			goto out;
514		}
515		vnx->vx_pending++;
516		bgetvp(vp, &nbp->vb_buf);
517		BUFQ_PUT(&vnd->sc_tab, &nbp->vb_buf);
518		vndstart(vnd);
519		splx(s);
520		bn += sz;
521		addr += sz;
522	}
523
524	s = splbio();
525
526out: /* Arrive here at splbio */
527	vnx->vx_flags &= ~VX_BUSY;
528	if (vnx->vx_pending == 0) {
529		if (vnx->vx_error != 0) {
530			bp->b_error = vnx->vx_error;
531			bp->b_flags |= B_ERROR;
532		}
533		VND_PUTXFER(vnd, vnx);
534		biodone(bp);
535	}
536	splx(s);
537	return;
538
539 done:
540	biodone(bp);
541}
542
543/*
544 * Feed requests sequentially.
545 * We do it this way to keep from flooding NFS servers if we are connected
546 * to an NFS file.  This places the burden on the client rather than the
547 * server.
548 */
549void
550vndstart(vnd)
551	struct vnd_softc *vnd;
552{
553	struct buf	*bp;
554
555	/*
556	 * Dequeue now since lower level strategy routine might
557	 * queue using same links
558	 */
559
560	if ((vnd->sc_flags & VNF_BUSY) != 0)
561		return;
562
563	vnd->sc_flags |= VNF_BUSY;
564
565	while (vnd->sc_active < vnd->sc_maxactive) {
566		bp = BUFQ_GET(&vnd->sc_tab);
567		if (bp == NULL)
568			break;
569		vnd->sc_active++;
570#ifdef DEBUG
571		if (vnddebug & VDB_IO)
572			printf("vndstart(%ld): bp %p vp %p blkno 0x%" PRIx64
573				" flags %lx addr %p cnt 0x%lx\n",
574			    (long) (vnd-vnd_softc), bp, bp->b_vp, bp->b_blkno,
575			    bp->b_flags, bp->b_data, bp->b_bcount);
576#endif
577
578		/* Instrumentation. */
579		disk_busy(&vnd->sc_dkdev);
580
581		if ((bp->b_flags & B_READ) == 0)
582			bp->b_vp->v_numoutput++;
583		VOP_STRATEGY(bp);
584	}
585	vnd->sc_flags &= ~VNF_BUSY;
586}
587
588void
589vndiodone(bp)
590	struct buf *bp;
591{
592	struct vndbuf *vbp = (struct vndbuf *) bp;
593	struct vndxfer *vnx = (struct vndxfer *)vbp->vb_xfer;
594	struct buf *pbp = vnx->vx_bp;
595	struct vnd_softc *vnd = &vnd_softc[vndunit(pbp->b_dev)];
596	int s, resid;
597
598	s = splbio();
599#ifdef DEBUG
600	if (vnddebug & VDB_IO)
601		printf("vndiodone(%ld): vbp %p vp %p blkno 0x%" PRIx64
602		       " addr %p cnt 0x%lx\n",
603		    (long) (vnd-vnd_softc), vbp, vbp->vb_buf.b_vp,
604		    vbp->vb_buf.b_blkno, vbp->vb_buf.b_data,
605		    vbp->vb_buf.b_bcount);
606#endif
607
608	resid = vbp->vb_buf.b_bcount - vbp->vb_buf.b_resid;
609	pbp->b_resid -= resid;
610	disk_unbusy(&vnd->sc_dkdev, resid, (pbp->b_flags & B_READ));
611	vnx->vx_pending--;
612
613	if (vbp->vb_buf.b_error) {
614#ifdef DEBUG
615		if (vnddebug & VDB_IO)
616			printf("vndiodone: vbp %p error %d\n", vbp,
617			    vbp->vb_buf.b_error);
618#endif
619		vnx->vx_error = vbp->vb_buf.b_error;
620	}
621
622	if (vbp->vb_buf.b_vp != NULLVP)
623		brelvp(&vbp->vb_buf);
624
625	VND_PUTBUF(vnd, vbp);
626
627	/*
628	 * Wrap up this transaction if it has run to completion or, in
629	 * case of an error, when all auxiliary buffers have returned.
630	 */
631	if (vnx->vx_error != 0) {
632		pbp->b_flags |= B_ERROR;
633		pbp->b_error = vnx->vx_error;
634		if ((vnx->vx_flags & VX_BUSY) == 0 && vnx->vx_pending == 0) {
635
636#ifdef DEBUG
637			if (vnddebug & VDB_IO)
638				printf("vndiodone: pbp %p iodone: error %d\n",
639					pbp, vnx->vx_error);
640#endif
641			VND_PUTXFER(vnd, vnx);
642			biodone(pbp);
643		}
644	} else if (pbp->b_resid == 0) {
645
646#ifdef DIAGNOSTIC
647		if (vnx->vx_pending != 0)
648			panic("vndiodone: vnx pending: %d", vnx->vx_pending);
649#endif
650
651		if ((vnx->vx_flags & VX_BUSY) == 0) {
652#ifdef DEBUG
653			if (vnddebug & VDB_IO)
654				printf("vndiodone: pbp %p iodone\n", pbp);
655#endif
656			VND_PUTXFER(vnd, vnx);
657			biodone(pbp);
658		}
659	}
660
661	vnd->sc_active--;
662	vndstart(vnd);
663	splx(s);
664}
665
666/* ARGSUSED */
667int
668vndread(dev, uio, flags)
669	dev_t dev;
670	struct uio *uio;
671	int flags;
672{
673	int unit = vndunit(dev);
674	struct vnd_softc *sc;
675
676#ifdef DEBUG
677	if (vnddebug & VDB_FOLLOW)
678		printf("vndread(0x%x, %p)\n", dev, uio);
679#endif
680
681	if (unit >= numvnd)
682		return (ENXIO);
683	sc = &vnd_softc[unit];
684
685	if ((sc->sc_flags & VNF_INITED) == 0)
686		return (ENXIO);
687
688	return (physio(vndstrategy, NULL, dev, B_READ, minphys, uio));
689}
690
691/* ARGSUSED */
692int
693vndwrite(dev, uio, flags)
694	dev_t dev;
695	struct uio *uio;
696	int flags;
697{
698	int unit = vndunit(dev);
699	struct vnd_softc *sc;
700
701#ifdef DEBUG
702	if (vnddebug & VDB_FOLLOW)
703		printf("vndwrite(0x%x, %p)\n", dev, uio);
704#endif
705
706	if (unit >= numvnd)
707		return (ENXIO);
708	sc = &vnd_softc[unit];
709
710	if ((sc->sc_flags & VNF_INITED) == 0)
711		return (ENXIO);
712
713	return (physio(vndstrategy, NULL, dev, B_WRITE, minphys, uio));
714}
715
716/* ARGSUSED */
717int
718vndioctl(dev, cmd, data, flag, p)
719	dev_t dev;
720	u_long cmd;
721	caddr_t data;
722	int flag;
723	struct proc *p;
724{
725	int unit = vndunit(dev);
726	struct vnd_softc *vnd;
727	struct vnd_ioctl *vio;
728	struct vattr vattr;
729	struct nameidata nd;
730	int error, part, pmask;
731	size_t geomsize;
732#ifdef __HAVE_OLD_DISKLABEL
733	struct disklabel newlabel;
734#endif
735
736#ifdef DEBUG
737	if (vnddebug & VDB_FOLLOW)
738		printf("vndioctl(0x%x, 0x%lx, %p, 0x%x, %p): unit %d\n",
739		    dev, cmd, data, flag, p, unit);
740#endif
741	error = suser(p->p_ucred, &p->p_acflag);
742	if (error)
743		return (error);
744	if (unit >= numvnd)
745		return (ENXIO);
746
747	vnd = &vnd_softc[unit];
748	vio = (struct vnd_ioctl *)data;
749
750	/* Must be open for writes for these commands... */
751	switch (cmd) {
752	case VNDIOCSET:
753	case VNDIOCCLR:
754	case DIOCSDINFO:
755	case DIOCWDINFO:
756#ifdef __HAVE_OLD_DISKLABEL
757	case ODIOCSDINFO:
758	case ODIOCWDINFO:
759#endif
760	case DIOCWLABEL:
761		if ((flag & FWRITE) == 0)
762			return (EBADF);
763	}
764
765	/* Must be initialized for these... */
766	switch (cmd) {
767	case VNDIOCCLR:
768	case DIOCGDINFO:
769	case DIOCSDINFO:
770	case DIOCWDINFO:
771	case DIOCGPART:
772	case DIOCWLABEL:
773	case DIOCGDEFLABEL:
774#ifdef __HAVE_OLD_DISKLABEL
775	case ODIOCGDINFO:
776	case ODIOCSDINFO:
777	case ODIOCWDINFO:
778	case ODIOCGDEFLABEL:
779#endif
780		if ((vnd->sc_flags & VNF_INITED) == 0)
781			return (ENXIO);
782	}
783
784	switch (cmd) {
785	case VNDIOCSET:
786		if (vnd->sc_flags & VNF_INITED)
787			return (EBUSY);
788
789		if ((error = vndlock(vnd)) != 0)
790			return (error);
791
792		/*
793		 * Always open for read and write.
794		 * This is probably bogus, but it lets vn_open()
795		 * weed out directories, sockets, etc. so we don't
796		 * have to worry about them.
797		 */
798		NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, vio->vnd_file, p);
799		if ((error = vn_open(&nd, FREAD|FWRITE, 0)) != 0)
800			goto unlock_and_exit;
801		error = VOP_GETATTR(nd.ni_vp, &vattr, p->p_ucred, p);
802		VOP_UNLOCK(nd.ni_vp, 0);
803		if (error)
804			goto close_and_exit;
805		vnd->sc_vp = nd.ni_vp;
806		vnd->sc_size = btodb(vattr.va_size);	/* note truncation */
807
808		/*
809		 * Use pseudo-geometry specified.  If none was provided,
810		 * use "standard" Adaptec fictitious geometry.
811		 */
812		if (vio->vnd_flags & VNDIOF_HASGEOM) {
813
814			memcpy(&vnd->sc_geom, &vio->vnd_geom,
815			    sizeof(vio->vnd_geom));
816
817			/*
818			 * Sanity-check the sector size.
819			 * XXX Don't allow secsize < DEV_BSIZE.  Should
820			 * XXX we?
821			 */
822			if (vnd->sc_geom.vng_secsize < DEV_BSIZE ||
823			    (vnd->sc_geom.vng_secsize % DEV_BSIZE) != 0) {
824				error = EINVAL;
825				goto close_and_exit;
826			}
827
828			/*
829			 * Compute the size (in DEV_BSIZE blocks) specified
830			 * by the geometry.
831			 */
832			geomsize = (vnd->sc_geom.vng_nsectors *
833			    vnd->sc_geom.vng_ntracks *
834			    vnd->sc_geom.vng_ncylinders) *
835			    (vnd->sc_geom.vng_secsize / DEV_BSIZE);
836
837			/*
838			 * Sanity-check the size against the specified
839			 * geometry.
840			 */
841			if (vnd->sc_size < geomsize) {
842				error = EINVAL;
843				goto close_and_exit;
844			}
845		} else {
846			/*
847			 * Size must be at least 2048 DEV_BSIZE blocks
848			 * (1M) in order to use this geometry.
849			 */
850			if (vnd->sc_size < (32 * 64)) {
851				error = EINVAL;
852				goto close_and_exit;
853			}
854
855			vnd->sc_geom.vng_secsize = DEV_BSIZE;
856			vnd->sc_geom.vng_nsectors = 32;
857			vnd->sc_geom.vng_ntracks = 64;
858			vnd->sc_geom.vng_ncylinders = vnd->sc_size / (64 * 32);
859		}
860
861		if ((error = vndsetcred(vnd, p->p_ucred)) != 0)
862			goto close_and_exit;
863		vndthrottle(vnd, vnd->sc_vp);
864		vio->vnd_size = dbtob(vnd->sc_size);
865		vnd->sc_flags |= VNF_INITED;
866#ifdef DEBUG
867		if (vnddebug & VDB_INIT)
868			printf("vndioctl: SET vp %p size 0x%lx %d/%d/%d/%d\n",
869			    vnd->sc_vp, (unsigned long) vnd->sc_size,
870			    vnd->sc_geom.vng_secsize,
871			    vnd->sc_geom.vng_nsectors,
872			    vnd->sc_geom.vng_ntracks,
873			    vnd->sc_geom.vng_ncylinders);
874#endif
875
876		/* Attach the disk. */
877		memset(vnd->sc_xname, 0, sizeof(vnd->sc_xname)); /* XXX */
878		sprintf(vnd->sc_xname, "vnd%d", unit);		/* XXX */
879		vnd->sc_dkdev.dk_name = vnd->sc_xname;
880		disk_attach(&vnd->sc_dkdev);
881
882		/* Initialize the xfer and buffer pools. */
883		pool_init(&vnd->sc_vxpool, sizeof(struct vndxfer), 0,
884		    0, 0, "vndxpl", NULL);
885		pool_init(&vnd->sc_vbpool, sizeof(struct vndbuf), 0,
886		    0, 0, "vndbpl", NULL);
887
888		/* Try and read the disklabel. */
889		vndgetdisklabel(dev);
890
891		vndunlock(vnd);
892
893		break;
894
895close_and_exit:
896		(void) vn_close(nd.ni_vp, FREAD|FWRITE, p->p_ucred, p);
897unlock_and_exit:
898		vndunlock(vnd);
899		return (error);
900
901	case VNDIOCCLR:
902		if ((error = vndlock(vnd)) != 0)
903			return (error);
904
905		/*
906		 * Don't unconfigure if any other partitions are open
907		 * or if both the character and block flavors of this
908		 * partition are open.
909		 */
910		part = DISKPART(dev);
911		pmask = (1 << part);
912		if ((vnd->sc_dkdev.dk_openmask & ~pmask) ||
913		    ((vnd->sc_dkdev.dk_bopenmask & pmask) &&
914		    (vnd->sc_dkdev.dk_copenmask & pmask))) {
915			vndunlock(vnd);
916			return (EBUSY);
917		}
918
919		vndclear(vnd);
920#ifdef DEBUG
921		if (vnddebug & VDB_INIT)
922			printf("vndioctl: CLRed\n");
923#endif
924
925		/* Destroy the xfer and buffer pools. */
926		pool_destroy(&vnd->sc_vxpool);
927		pool_destroy(&vnd->sc_vbpool);
928
929		/* Detatch the disk. */
930		disk_detach(&vnd->sc_dkdev);
931
932		vndunlock(vnd);
933
934		break;
935
936	case VNDIOCGET: {
937		struct vnd_user *vnu;
938		struct vattr va;
939
940		vnu = (struct vnd_user *)data;
941
942		if (vnu->vnu_unit == -1)
943			vnu->vnu_unit = unit;
944		if (vnu->vnu_unit >= numvnd)
945			return (ENXIO);
946		if (vnu->vnu_unit < 0)
947			return (EINVAL);
948
949		vnd = &vnd_softc[vnu->vnu_unit];
950
951		if (vnd->sc_flags & VNF_INITED) {
952			error = VOP_GETATTR(vnd->sc_vp, &va, p->p_ucred, p);
953			if (error)
954				return (error);
955			vnu->vnu_dev = va.va_fsid;
956			vnu->vnu_ino = va.va_fileid;
957		}
958		else {
959			/* unused is not an error */
960			vnu->vnu_dev = 0;
961			vnu->vnu_ino = 0;
962		}
963
964		break;
965	}
966
967	case DIOCGDINFO:
968		*(struct disklabel *)data = *(vnd->sc_dkdev.dk_label);
969		break;
970
971#ifdef __HAVE_OLD_DISKLABEL
972	case ODIOCGDINFO:
973		newlabel = *(vnd->sc_dkdev.dk_label);
974		if (newlabel.d_npartitions > OLDMAXPARTITIONS)
975			return ENOTTY;
976		memcpy(data, &newlabel, sizeof (struct olddisklabel));
977		break;
978#endif
979
980	case DIOCGPART:
981		((struct partinfo *)data)->disklab = vnd->sc_dkdev.dk_label;
982		((struct partinfo *)data)->part =
983		    &vnd->sc_dkdev.dk_label->d_partitions[DISKPART(dev)];
984		break;
985
986	case DIOCWDINFO:
987	case DIOCSDINFO:
988#ifdef __HAVE_OLD_DISKLABEL
989	case ODIOCWDINFO:
990	case ODIOCSDINFO:
991#endif
992	{
993		struct disklabel *lp;
994
995		if ((error = vndlock(vnd)) != 0)
996			return (error);
997
998		vnd->sc_flags |= VNF_LABELLING;
999
1000#ifdef __HAVE_OLD_DISKLABEL
1001		if (cmd == ODIOCSDINFO || cmd == ODIOCWDINFO) {
1002			memset(&newlabel, 0, sizeof newlabel);
1003			memcpy(&newlabel, data, sizeof (struct olddisklabel));
1004			lp = &newlabel;
1005		} else
1006#endif
1007		lp = (struct disklabel *)data;
1008
1009		error = setdisklabel(vnd->sc_dkdev.dk_label,
1010		    lp, 0, vnd->sc_dkdev.dk_cpulabel);
1011		if (error == 0) {
1012			if (cmd == DIOCWDINFO
1013#ifdef __HAVE_OLD_DISKLABEL
1014			    || cmd == ODIOCWDINFO
1015#endif
1016			   )
1017				error = writedisklabel(VNDLABELDEV(dev),
1018				    vndstrategy, vnd->sc_dkdev.dk_label,
1019				    vnd->sc_dkdev.dk_cpulabel);
1020		}
1021
1022		vnd->sc_flags &= ~VNF_LABELLING;
1023
1024		vndunlock(vnd);
1025
1026		if (error)
1027			return (error);
1028		break;
1029	}
1030
1031	case DIOCWLABEL:
1032		if (*(int *)data != 0)
1033			vnd->sc_flags |= VNF_WLABEL;
1034		else
1035			vnd->sc_flags &= ~VNF_WLABEL;
1036		break;
1037
1038	case DIOCGDEFLABEL:
1039		vndgetdefaultlabel(vnd, (struct disklabel *)data);
1040		break;
1041
1042#ifdef __HAVE_OLD_DISKLABEL
1043	case ODIOCGDEFLABEL:
1044		vndgetdefaultlabel(vnd, &newlabel);
1045		if (newlabel.d_npartitions > OLDMAXPARTITIONS)
1046			return ENOTTY;
1047		memcpy(data, &newlabel, sizeof (struct olddisklabel));
1048		break;
1049#endif
1050
1051	default:
1052		return (ENOTTY);
1053	}
1054
1055	return (0);
1056}
1057
1058/*
1059 * Duplicate the current processes' credentials.  Since we are called only
1060 * as the result of a SET ioctl and only root can do that, any future access
1061 * to this "disk" is essentially as root.  Note that credentials may change
1062 * if some other uid can write directly to the mapped file (NFS).
1063 */
1064int
1065vndsetcred(vnd, cred)
1066	struct vnd_softc *vnd;
1067	struct ucred *cred;
1068{
1069	struct uio auio;
1070	struct iovec aiov;
1071	char *tmpbuf;
1072	int error;
1073
1074	vnd->sc_cred = crdup(cred);
1075	tmpbuf = malloc(DEV_BSIZE, M_TEMP, M_WAITOK);
1076
1077	/* XXX: Horrible kludge to establish credentials for NFS */
1078	aiov.iov_base = tmpbuf;
1079	aiov.iov_len = min(DEV_BSIZE, dbtob(vnd->sc_size));
1080	auio.uio_iov = &aiov;
1081	auio.uio_iovcnt = 1;
1082	auio.uio_offset = 0;
1083	auio.uio_rw = UIO_READ;
1084	auio.uio_segflg = UIO_SYSSPACE;
1085	auio.uio_resid = aiov.iov_len;
1086	vn_lock(vnd->sc_vp, LK_EXCLUSIVE | LK_RETRY);
1087	error = VOP_READ(vnd->sc_vp, &auio, 0, vnd->sc_cred);
1088	if (error == 0) {
1089		/*
1090		 * Because vnd does all IO directly through the vnode
1091		 * we need to flush (at least) the buffer from the above
1092		 * VOP_READ from the buffer cache to prevent cache
1093		 * incoherencies.  Also, be careful to write dirty
1094		 * buffers back to stable storage.
1095		 */
1096		error = vinvalbuf(vnd->sc_vp, V_SAVE, vnd->sc_cred,
1097			    curproc, 0, 0);
1098	}
1099	VOP_UNLOCK(vnd->sc_vp, 0);
1100
1101	free(tmpbuf, M_TEMP);
1102	return (error);
1103}
1104
1105/*
1106 * Set maxactive based on FS type
1107 */
1108void
1109vndthrottle(vnd, vp)
1110	struct vnd_softc *vnd;
1111	struct vnode *vp;
1112{
1113#ifdef NFS
1114	extern int (**nfsv2_vnodeop_p) __P((void *));
1115
1116	if (vp->v_op == nfsv2_vnodeop_p)
1117		vnd->sc_maxactive = 2;
1118	else
1119#endif
1120		vnd->sc_maxactive = 8;
1121
1122	if (vnd->sc_maxactive < 1)
1123		vnd->sc_maxactive = 1;
1124}
1125
1126void
1127vndshutdown()
1128{
1129	struct vnd_softc *vnd;
1130
1131	for (vnd = &vnd_softc[0]; vnd < &vnd_softc[numvnd]; vnd++)
1132		if (vnd->sc_flags & VNF_INITED)
1133			vndclear(vnd);
1134}
1135
1136void
1137vndclear(vnd)
1138	struct vnd_softc *vnd;
1139{
1140	struct vnode *vp = vnd->sc_vp;
1141	struct proc *p = curproc;		/* XXX */
1142
1143#ifdef DEBUG
1144	if (vnddebug & VDB_FOLLOW)
1145		printf("vndclear(%p): vp %p\n", vnd, vp);
1146#endif
1147	vnd->sc_flags &= ~VNF_INITED;
1148	if (vp == (struct vnode *)0)
1149		panic("vndioctl: null vp");
1150	(void) vn_close(vp, FREAD|FWRITE, vnd->sc_cred, p);
1151	crfree(vnd->sc_cred);
1152	vnd->sc_vp = (struct vnode *)0;
1153	vnd->sc_cred = (struct ucred *)0;
1154	vnd->sc_size = 0;
1155}
1156
1157int
1158vndsize(dev)
1159	dev_t dev;
1160{
1161	struct vnd_softc *sc;
1162	struct disklabel *lp;
1163	int part, unit, omask;
1164	int size;
1165
1166	unit = vndunit(dev);
1167	if (unit >= numvnd)
1168		return (-1);
1169	sc = &vnd_softc[unit];
1170
1171	if ((sc->sc_flags & VNF_INITED) == 0)
1172		return (-1);
1173
1174	part = DISKPART(dev);
1175	omask = sc->sc_dkdev.dk_openmask & (1 << part);
1176	lp = sc->sc_dkdev.dk_label;
1177
1178	if (omask == 0 && vndopen(dev, 0, S_IFBLK, curproc))
1179		return (-1);
1180
1181	if (lp->d_partitions[part].p_fstype != FS_SWAP)
1182		size = -1;
1183	else
1184		size = lp->d_partitions[part].p_size *
1185		    (lp->d_secsize / DEV_BSIZE);
1186
1187	if (omask == 0 && vndclose(dev, 0, S_IFBLK, curproc))
1188		return (-1);
1189
1190	return (size);
1191}
1192
1193int
1194vnddump(dev, blkno, va, size)
1195	dev_t dev;
1196	daddr_t blkno;
1197	caddr_t va;
1198	size_t size;
1199{
1200
1201	/* Not implemented. */
1202	return ENXIO;
1203}
1204
1205void
1206vndgetdefaultlabel(sc, lp)
1207	struct vnd_softc *sc;
1208	struct disklabel *lp;
1209{
1210	struct vndgeom *vng = &sc->sc_geom;
1211	struct partition *pp;
1212
1213	memset(lp, 0, sizeof(*lp));
1214
1215	lp->d_secperunit = sc->sc_size / (vng->vng_secsize / DEV_BSIZE);
1216	lp->d_secsize = vng->vng_secsize;
1217	lp->d_nsectors = vng->vng_nsectors;
1218	lp->d_ntracks = vng->vng_ntracks;
1219	lp->d_ncylinders = vng->vng_ncylinders;
1220	lp->d_secpercyl = lp->d_ntracks * lp->d_nsectors;
1221
1222	strncpy(lp->d_typename, "vnd", sizeof(lp->d_typename));
1223	lp->d_type = DTYPE_VND;
1224	strncpy(lp->d_packname, "fictitious", sizeof(lp->d_packname));
1225	lp->d_rpm = 3600;
1226	lp->d_interleave = 1;
1227	lp->d_flags = 0;
1228
1229	pp = &lp->d_partitions[RAW_PART];
1230	pp->p_offset = 0;
1231	pp->p_size = lp->d_secperunit;
1232	pp->p_fstype = FS_UNUSED;
1233	lp->d_npartitions = RAW_PART + 1;
1234
1235	lp->d_magic = DISKMAGIC;
1236	lp->d_magic2 = DISKMAGIC;
1237	lp->d_checksum = dkcksum(lp);
1238}
1239
1240/*
1241 * Read the disklabel from a vnd.  If one is not present, create a fake one.
1242 */
1243void
1244vndgetdisklabel(dev)
1245	dev_t dev;
1246{
1247	struct vnd_softc *sc = &vnd_softc[vndunit(dev)];
1248	char *errstring;
1249	struct disklabel *lp = sc->sc_dkdev.dk_label;
1250	struct cpu_disklabel *clp = sc->sc_dkdev.dk_cpulabel;
1251	int i;
1252
1253	memset(clp, 0, sizeof(*clp));
1254
1255	vndgetdefaultlabel(sc, lp);
1256
1257	/*
1258	 * Call the generic disklabel extraction routine.
1259	 */
1260	errstring = readdisklabel(VNDLABELDEV(dev), vndstrategy, lp, clp);
1261	if (errstring) {
1262		/*
1263		 * Lack of disklabel is common, but we print the warning
1264		 * anyway, since it might contain other useful information.
1265		 */
1266		printf("%s: %s\n", sc->sc_xname, errstring);
1267
1268		/*
1269		 * For historical reasons, if there's no disklabel
1270		 * present, all partitions must be FS_BSDFFS and
1271		 * occupy the entire disk.
1272		 */
1273		for (i = 0; i < MAXPARTITIONS; i++) {
1274			/*
1275			 * Don't wipe out port specific hack (such as
1276			 * dos partition hack of i386 port).
1277			 */
1278			if (lp->d_partitions[i].p_fstype != FS_UNUSED)
1279				continue;
1280
1281			lp->d_partitions[i].p_size = lp->d_secperunit;
1282			lp->d_partitions[i].p_offset = 0;
1283			lp->d_partitions[i].p_fstype = FS_BSDFFS;
1284		}
1285
1286		strncpy(lp->d_packname, "default label",
1287		    sizeof(lp->d_packname));
1288
1289		lp->d_checksum = dkcksum(lp);
1290	}
1291}
1292
1293/*
1294 * Wait interruptibly for an exclusive lock.
1295 *
1296 * XXX
1297 * Several drivers do this; it should be abstracted and made MP-safe.
1298 */
1299static int
1300vndlock(sc)
1301	struct vnd_softc *sc;
1302{
1303	int error;
1304
1305	while ((sc->sc_flags & VNF_LOCKED) != 0) {
1306		sc->sc_flags |= VNF_WANTED;
1307		if ((error = tsleep(sc, PRIBIO | PCATCH, "vndlck", 0)) != 0)
1308			return (error);
1309	}
1310	sc->sc_flags |= VNF_LOCKED;
1311	return (0);
1312}
1313
1314/*
1315 * Unlock and wake up any waiters.
1316 */
1317static void
1318vndunlock(sc)
1319	struct vnd_softc *sc;
1320{
1321
1322	sc->sc_flags &= ~VNF_LOCKED;
1323	if ((sc->sc_flags & VNF_WANTED) != 0) {
1324		sc->sc_flags &= ~VNF_WANTED;
1325		wakeup(sc);
1326	}
1327}
1328