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freebsd-skq/sys/dev/vn/vn.c
dfr 8ccd49e34b Fix another DEVFS/SLICE ioctl.
1998-06-07 20:10:53 +00:00

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/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: Utah Hdr: vn.c 1.13 94/04/02
*
* from: @(#)vn.c 8.6 (Berkeley) 4/1/94
* $Id: vn.c,v 1.60 1998/06/07 17:09:50 dfr Exp $
*/
/*
* Vnode disk driver.
*
* Block/character interface to a vnode. Allows one to treat a file
* as a disk (e.g. build a filesystem in it, mount it, etc.).
*
* NOTE 1: This uses the VOP_BMAP/VOP_STRATEGY interface to the vnode
* instead of a simple VOP_RDWR. We do this to avoid distorting the
* local buffer cache.
*
* NOTE 2: There is a security issue involved with this driver.
* Once mounted all access to the contents of the "mapped" file via
* the special file is controlled by the permissions on the special
* file, the protection of the mapped file is ignored (effectively,
* by using root credentials in all transactions).
*
* NOTE 3: Doesn't interact with leases, should it?
*/
#include "vn.h"
#if NVN > 0
/* default is to have 8 VN's */
#if NVN < 8
#undef NVN
#define NVN 8
#endif
#include "opt_devfs.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/buf.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/fcntl.h>
#include <sys/disklabel.h>
#include <sys/diskslice.h>
#include <sys/stat.h>
#include <sys/conf.h>
#ifdef SLICE
#include <sys/device.h>
#include <dev/slice/slice.h>
#endif /* SLICE */
#include <miscfs/specfs/specdev.h>
#include <sys/vnioctl.h>
static d_ioctl_t vnioctl;
#ifndef SLICE
static d_open_t vnopen;
static d_close_t vnclose;
static d_dump_t vndump;
static d_psize_t vnsize;
static d_strategy_t vnstrategy;
#define CDEV_MAJOR 43
#define BDEV_MAJOR 15
static struct cdevsw vn_cdevsw;
static struct bdevsw vn_bdevsw =
{ vnopen, vnclose, vnstrategy, vnioctl, /*15*/
vndump, vnsize, D_DISK | D_NOCLUSTERRW, "vn", &vn_cdevsw, -1 };
#else /* SLICE */
static sl_h_IO_req_t nvsIOreq; /* IO req downward (to device) */
static sl_h_ioctl_t nvsioctl; /* ioctl req downward (to device) */
static sl_h_open_t nvsopen; /* downwards travelling open */
/*static sl_h_close_t nvsclose; */ /* downwards travelling close */
static sl_h_dump_t nvsdump; /* core dump req downward */
static struct slice_handler slicetype = {
"vn",
0,
NULL,
0,
NULL, /* constructor */
&nvsIOreq,
&nvsioctl,
&nvsopen,
/*&nvsclose*/NULL,
NULL, /* revoke */
NULL, /* claim */
NULL, /* verify */
NULL, /* upconfig */
&nvsdump
};
#endif
#define vnunit(dev) dkunit(dev)
#define getvnbuf() \
((struct buf *)malloc(sizeof(struct buf), M_DEVBUF, M_WAITOK))
#define putvnbuf(bp) \
free((caddr_t)(bp), M_DEVBUF)
struct vn_softc {
int sc_flags; /* flags */
size_t sc_size; /* size of vn */
#ifdef SLICE
struct slice *slice;
struct slicelimits limit;
int mynor;
int unit;
#else
struct diskslices *sc_slices;
#endif /* SLICE */
struct vnode *sc_vp; /* vnode */
struct ucred *sc_cred; /* credentials */
int sc_maxactive; /* max # of active requests */
struct buf sc_tab; /* transfer queue */
u_long sc_options; /* options */
};
/* sc_flags */
#define VNF_INITED 0x01
static struct vn_softc *vn_softc[NVN];
static u_long vn_options;
#define IFOPT(vn,opt) if (((vn)->sc_options|vn_options) & (opt))
static void vniodone (struct buf *bp);
static int vnsetcred (struct vn_softc *vn, struct ucred *cred);
static void vnshutdown (int, void *);
static void vnclear (struct vn_softc *vn);
#ifndef SLICE
static int
vnclose(dev_t dev, int flags, int mode, struct proc *p)
{
struct vn_softc *vn = vn_softc[vnunit(dev)];
IFOPT(vn, VN_LABELS)
if (vn->sc_slices != NULL)
dsclose(dev, mode, vn->sc_slices);
return (0);
}
static int
vnopen(dev_t dev, int flags, int mode, struct proc *p)
{
int unit = vnunit(dev);
struct vn_softc *vn;
if (unit >= NVN) {
if (vn_options & VN_FOLLOW)
printf("vnopen(0x%lx, 0x%x, 0x%x, %p)\n",
dev, flags, mode, p);
return(ENOENT);
}
vn = vn_softc[unit];
if (!vn) {
vn = malloc(sizeof *vn, M_DEVBUF, M_WAITOK);
if (!vn)
return (ENOMEM);
bzero(vn, sizeof *vn);
vn_softc[unit] = vn;
}
IFOPT(vn, VN_FOLLOW)
printf("vnopen(0x%lx, 0x%x, 0x%x, %p)\n", dev, flags, mode, p);
IFOPT(vn, VN_LABELS) {
if (vn->sc_flags & VNF_INITED) {
struct disklabel label;
/* Build label for whole disk. */
bzero(&label, sizeof label);
label.d_secsize = DEV_BSIZE;
label.d_nsectors = 32;
label.d_ntracks = 64;
label.d_ncylinders = vn->sc_size / (32 * 64);
label.d_secpercyl = 32 * 64;
label.d_secperunit =
label.d_partitions[RAW_PART].p_size =
vn->sc_size;
return (dsopen("vn", dev, mode, &vn->sc_slices, &label,
vnstrategy, (ds_setgeom_t *)NULL,
&vn_bdevsw, &vn_cdevsw));
}
if (dkslice(dev) != WHOLE_DISK_SLICE ||
dkpart(dev) != RAW_PART ||
mode != S_IFCHR)
return (ENXIO);
}
return(0);
}
/*
* this code does I/O calls through the appropriate VOP entry point...
* unless a swap_pager I/O request is being done. This strategy (-))
* allows for coherency with mmap except in the case of paging. This
* is necessary, because the VOP calls use lots of memory (and actually
* are not extremely efficient -- but we want to keep semantics correct),
* and the pageout daemon gets really unhappy (and so does the rest of the
* system) when it runs out of memory.
*/
static void
vnstrategy(struct buf *bp)
{
int unit = vnunit(bp->b_dev);
register struct vn_softc *vn = vn_softc[unit];
register daddr_t bn;
int error;
int isvplocked = 0;
long sz;
struct uio auio;
struct iovec aiov;
IFOPT(vn, VN_DEBUG)
printf("vnstrategy(%p): unit %d\n", bp, unit);
if ((vn->sc_flags & VNF_INITED) == 0) {
bp->b_error = ENXIO;
bp->b_flags |= B_ERROR;
biodone(bp);
return;
}
IFOPT(vn, VN_LABELS) {
bp->b_resid = bp->b_bcount;/* XXX best place to set this? */
if (vn->sc_slices != NULL && dscheck(bp, vn->sc_slices) <= 0) {
biodone(bp);
return;
}
bn = bp->b_pblkno;
bp->b_resid = bp->b_bcount;/* XXX best place to set this? */
} else {
bn = bp->b_blkno;
sz = howmany(bp->b_bcount, DEV_BSIZE);
bp->b_resid = bp->b_bcount;
if (bn < 0 || bn + sz > vn->sc_size) {
if (bn != vn->sc_size) {
bp->b_error = EINVAL;
bp->b_flags |= B_ERROR;
}
biodone(bp);
return;
}
}
if( (bp->b_flags & B_PAGING) == 0) {
aiov.iov_base = bp->b_data;
aiov.iov_len = bp->b_bcount;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = dbtob(bn);
auio.uio_segflg = UIO_SYSSPACE;
if( bp->b_flags & B_READ)
auio.uio_rw = UIO_READ;
else
auio.uio_rw = UIO_WRITE;
auio.uio_resid = bp->b_bcount;
auio.uio_procp = curproc;
if (!VOP_ISLOCKED(vn->sc_vp)) {
isvplocked = 1;
vn_lock(vn->sc_vp, LK_EXCLUSIVE | LK_RETRY, curproc);
}
if( bp->b_flags & B_READ)
error = VOP_READ(vn->sc_vp, &auio, 0, vn->sc_cred);
else
error = VOP_WRITE(vn->sc_vp, &auio, 0, vn->sc_cred);
if (isvplocked) {
VOP_UNLOCK(vn->sc_vp, 0, curproc);
isvplocked = 0;
}
bp->b_resid = auio.uio_resid;
if( error )
bp->b_flags |= B_ERROR;
biodone(bp);
} else {
long bsize, resid;
off_t byten;
int flags;
caddr_t addr;
struct buf *nbp;
nbp = getvnbuf();
byten = dbtob(bn);
bsize = vn->sc_vp->v_mount->mnt_stat.f_iosize;
addr = bp->b_data;
flags = bp->b_flags | B_CALL;
for (resid = bp->b_resid; resid; ) {
struct vnode *vp;
daddr_t nbn;
int off, s, nra;
nra = 0;
if (!VOP_ISLOCKED(vn->sc_vp)) {
isvplocked = 1;
vn_lock(vn->sc_vp, LK_EXCLUSIVE | LK_RETRY, curproc);
}
error = VOP_BMAP(vn->sc_vp, (daddr_t)(byten / bsize),
&vp, &nbn, &nra, NULL);
if (isvplocked) {
VOP_UNLOCK(vn->sc_vp, 0, curproc);
isvplocked = 0;
}
if (error == 0 && nbn == -1)
error = EIO;
IFOPT(vn, VN_DONTCLUSTER)
nra = 0;
off = byten % bsize;
if (off)
sz = bsize - off;
else
sz = (1 + nra) * bsize;
if (resid < sz)
sz = resid;
if (error) {
bp->b_resid -= (resid - sz);
bp->b_flags |= B_ERROR;
biodone(bp);
putvnbuf(nbp);
return;
}
IFOPT(vn,VN_IO)
printf(
/* XXX no %qx in kernel. Synthesize it. */
"vnstrategy: vp %p/%p bn 0x%lx%08lx/0x%lx sz 0x%x\n",
vn->sc_vp, vp, (long)(byten >> 32),
(u_long)byten, nbn, sz);
nbp->b_flags = flags;
nbp->b_bcount = sz;
nbp->b_bufsize = sz;
nbp->b_error = 0;
if (vp->v_type == VBLK || vp->v_type == VCHR)
nbp->b_dev = vp->v_rdev;
else
nbp->b_dev = NODEV;
nbp->b_data = addr;
nbp->b_blkno = nbn + btodb(off);
nbp->b_proc = bp->b_proc;
nbp->b_iodone = vniodone;
nbp->b_vp = vp;
nbp->b_rcred = vn->sc_cred; /* XXX crdup? */
nbp->b_wcred = vn->sc_cred; /* XXX crdup? */
nbp->b_dirtyoff = bp->b_dirtyoff;
nbp->b_dirtyend = bp->b_dirtyend;
nbp->b_validoff = bp->b_validoff;
nbp->b_validend = bp->b_validend;
if ((nbp->b_flags & B_READ) == 0)
nbp->b_vp->v_numoutput++;
VOP_STRATEGY(nbp);
s = splbio();
while ((nbp->b_flags & B_DONE) == 0) {
nbp->b_flags |= B_WANTED;
tsleep(nbp, PRIBIO, "vnwait", 0);
}
splx(s);
if( nbp->b_flags & B_ERROR) {
bp->b_flags |= B_ERROR;
bp->b_resid -= (resid - sz);
biodone(bp);
putvnbuf(nbp);
return;
}
byten += sz;
addr += sz;
resid -= sz;
}
biodone(bp);
putvnbuf(nbp);
}
}
#else /* SLICE */
static void
nvsIOreq(void *private ,struct buf *bp)
{
struct vn_softc *vn = private;
u_int32_t unit = vn->unit;
register daddr_t bn;
int error;
int isvplocked = 0;
long sz;
struct uio auio;
struct iovec aiov;
IFOPT(vn, VN_DEBUG)
printf("vnstrategy(%p): unit %d\n", bp, unit);
if ((vn->sc_flags & VNF_INITED) == 0) {
bp->b_error = ENXIO;
bp->b_flags |= B_ERROR;
biodone(bp);
return;
}
bn = bp->b_pblkno;
bp->b_resid = bp->b_bcount;/* XXX best place to set this? */
sz = howmany(bp->b_bcount, DEV_BSIZE);
if (bn < 0 || bn + sz > vn->sc_size) {
if (bn != vn->sc_size) {
bp->b_error = EINVAL;
bp->b_flags |= B_ERROR;
}
biodone(bp);
return;
}
if( (bp->b_flags & B_PAGING) == 0) {
aiov.iov_base = bp->b_data;
aiov.iov_len = bp->b_bcount;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = dbtob(bn);
auio.uio_segflg = UIO_SYSSPACE;
if( bp->b_flags & B_READ)
auio.uio_rw = UIO_READ;
else
auio.uio_rw = UIO_WRITE;
auio.uio_resid = bp->b_bcount;
auio.uio_procp = curproc;
if (!VOP_ISLOCKED(vn->sc_vp)) {
isvplocked = 1;
vn_lock(vn->sc_vp, LK_EXCLUSIVE | LK_RETRY, curproc);
}
if( bp->b_flags & B_READ)
error = VOP_READ(vn->sc_vp, &auio, 0, vn->sc_cred);
else
error = VOP_WRITE(vn->sc_vp, &auio, 0, vn->sc_cred);
if (isvplocked) {
VOP_UNLOCK(vn->sc_vp, 0, curproc);
isvplocked = 0;
}
bp->b_resid = auio.uio_resid;
if( error )
bp->b_flags |= B_ERROR;
biodone(bp);
} else {
long bsize, resid;
off_t byten;
int flags;
caddr_t addr;
struct buf *nbp;
nbp = getvnbuf();
byten = dbtob(bn);
/* This is probably the only time this is RIGHT */
bsize = vn->sc_vp->v_mount->mnt_stat.f_iosize;
addr = bp->b_data;
flags = bp->b_flags | B_CALL;
for (resid = bp->b_resid; resid; ) {
struct vnode *vp;
daddr_t nbn;
int off, s, nra;
nra = 0;
if (!VOP_ISLOCKED(vn->sc_vp)) {
isvplocked = 1;
vn_lock(vn->sc_vp, LK_EXCLUSIVE | LK_RETRY, curproc);
}
error = VOP_BMAP(vn->sc_vp, (daddr_t)(byten / bsize),
&vp, &nbn, &nra, NULL);
if (isvplocked) {
VOP_UNLOCK(vn->sc_vp, 0, curproc);
isvplocked = 0;
}
if (error == 0 && nbn == -1)
error = EIO;
IFOPT(vn, VN_DONTCLUSTER)
nra = 0;
off = byten % bsize;
if (off)
sz = bsize - off;
else
sz = (1 + nra) * bsize;
if (resid < sz)
sz = resid;
if (error) {
bp->b_resid -= (resid - sz);
bp->b_flags |= B_ERROR;
biodone(bp);
putvnbuf(nbp);
return;
}
IFOPT(vn,VN_IO)
printf(
/* XXX no %qx in kernel. Synthesize it. */
"vnstrategy: vp %p/%p bn 0x%lx%08lx/0x%lx sz 0x%x\n",
vn->sc_vp, vp, (long)(byten >> 32),
(u_long)byten, nbn, sz);
nbp->b_flags = flags;
nbp->b_bcount = sz;
nbp->b_bufsize = sz;
nbp->b_error = 0;
if (vp->v_type == VBLK || vp->v_type == VCHR)
nbp->b_dev = vp->v_rdev;
else
nbp->b_dev = NODEV;
nbp->b_data = addr;
nbp->b_blkno = nbn + btodb(off);
nbp->b_proc = bp->b_proc;
nbp->b_iodone = vniodone;
nbp->b_vp = vp;
nbp->b_rcred = vn->sc_cred; /* XXX crdup? */
nbp->b_wcred = vn->sc_cred; /* XXX crdup? */
nbp->b_dirtyoff = bp->b_dirtyoff;
nbp->b_dirtyend = bp->b_dirtyend;
nbp->b_validoff = bp->b_validoff;
nbp->b_validend = bp->b_validend;
if ((nbp->b_flags & B_READ) == 0)
nbp->b_vp->v_numoutput++;
VOP_STRATEGY(nbp);
s = splbio();
while ((nbp->b_flags & B_DONE) == 0) {
nbp->b_flags |= B_WANTED;
tsleep(nbp, PRIBIO, "vnwait", 0);
}
splx(s);
if( nbp->b_flags & B_ERROR) {
bp->b_flags |= B_ERROR;
bp->b_resid -= (resid - sz);
biodone(bp);
putvnbuf(nbp);
return;
}
byten += sz;
addr += sz;
resid -= sz;
}
biodone(bp);
putvnbuf(nbp);
}
}
#endif /* SLICE */
void
vniodone( struct buf *bp) {
bp->b_flags |= B_DONE;
wakeup((caddr_t) bp);
}
/* ARGSUSED */
static int
vnioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
{
struct vn_softc *vn = vn_softc[vnunit(dev)];
struct vn_ioctl *vio;
struct vattr vattr;
struct nameidata nd;
int error;
u_long *f;
#ifdef SLICE
sh_p tp;
#endif
IFOPT(vn,VN_FOLLOW)
printf("vnioctl(0x%lx, 0x%x, %p, 0x%x, %p): unit %d\n",
dev, cmd, data, flag, p, vnunit(dev));
switch (cmd) {
case VNIOCATTACH:
case VNIOCDETACH:
case VNIOCGSET:
case VNIOCGCLEAR:
case VNIOCUSET:
case VNIOCUCLEAR:
goto vn_specific;
}
#ifndef SLICE
IFOPT(vn,VN_LABELS) {
if (vn->sc_slices != NULL) {
error = dsioctl("vn", dev, cmd, data, flag,
&vn->sc_slices, vnstrategy,
(ds_setgeom_t *)NULL);
if (error != ENOIOCTL)
return (error);
}
if (dkslice(dev) != WHOLE_DISK_SLICE ||
dkpart(dev) != RAW_PART)
return (ENOTTY);
}
#endif
vn_specific:
error = suser(p->p_ucred, &p->p_acflag);
if (error)
return (error);
vio = (struct vn_ioctl *)data;
f = (u_long*)data;
switch (cmd) {
case VNIOCATTACH:
if (vn->sc_flags & VNF_INITED)
return(EBUSY);
/*
* Always open for read and write.
* This is probably bogus, but it lets vn_open()
* weed out directories, sockets, etc. so we don't
* have to worry about them.
*/
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, vio->vn_file, p);
error = vn_open(&nd, FREAD|FWRITE, 0);
if (error)
return(error);
error = VOP_GETATTR(nd.ni_vp, &vattr, p->p_ucred, p);
if (error) {
VOP_UNLOCK(nd.ni_vp, 0, p);
(void) vn_close(nd.ni_vp, FREAD|FWRITE, p->p_ucred, p);
return(error);
}
VOP_UNLOCK(nd.ni_vp, 0, p);
vn->sc_vp = nd.ni_vp;
vn->sc_size = btodb(vattr.va_size); /* note truncation */
error = vnsetcred(vn, p->p_ucred);
if (error) {
(void) vn_close(nd.ni_vp, FREAD|FWRITE, p->p_ucred, p);
return(error);
}
vio->vn_size = dbtob(vn->sc_size);
vn->sc_flags |= VNF_INITED;
#ifdef SLICE
/*
* XXX The filesystem blocksize will say 1024
* for a 8K filesystem. don't know yet how to deal with this,
* so lie for now.. say 512.
*/
#if 0
vn->limit.blksize = vn->sc_vp->v_mount->mnt_stat.f_bsize;
#else
vn->limit.blksize = DEV_BSIZE;
#endif
vn->slice->limits.blksize = vn->limit.blksize;
vn->limit.slicesize = vattr.va_size;
vn->slice->limits.slicesize = vattr.va_size;
/*
* We have a media to read/write.
* Try identify it.
*/
if ((tp = slice_probeall(vn->slice)) != NULL) {
(*tp->constructor)(vn->slice);
}
#else
IFOPT(vn, VN_LABELS) {
/*
* Reopen so that `ds' knows which devices are open.
* If this is the first VNIOCSET, then we've
* guaranteed that the device is the cdev and that
* no other slices or labels are open. Otherwise,
* we rely on VNIOCCLR not being abused.
*/
error = vnopen(dev, flag, S_IFCHR, p);
if (error)
vnclear(vn);
}
#endif
IFOPT(vn, VN_FOLLOW)
printf("vnioctl: SET vp %p size %x\n",
vn->sc_vp, vn->sc_size);
break;
case VNIOCDETACH:
if ((vn->sc_flags & VNF_INITED) == 0)
return(ENXIO);
/*
* XXX handle i/o in progress. Return EBUSY, or wait, or
* flush the i/o.
* XXX handle multiple opens of the device. Return EBUSY,
* or revoke the fd's.
* How are these problems handled for removable and failing
* hardware devices?
*/
vnclear(vn);
IFOPT(vn, VN_FOLLOW)
printf("vnioctl: CLRed\n");
break;
case VNIOCGSET:
vn_options |= *f;
*f = vn_options;
break;
case VNIOCGCLEAR:
vn_options &= ~(*f);
*f = vn_options;
break;
case VNIOCUSET:
vn->sc_options |= *f;
*f = vn->sc_options;
break;
case VNIOCUCLEAR:
vn->sc_options &= ~(*f);
*f = vn->sc_options;
break;
default:
return (ENOTTY);
}
return(0);
}
/*
* Duplicate the current processes' credentials. Since we are called only
* as the result of a SET ioctl and only root can do that, any future access
* to this "disk" is essentially as root. Note that credentials may change
* if some other uid can write directly to the mapped file (NFS).
*/
int
vnsetcred(struct vn_softc *vn, struct ucred *cred)
{
struct uio auio;
struct iovec aiov;
char *tmpbuf;
int error;
vn->sc_cred = crdup(cred);
tmpbuf = malloc(DEV_BSIZE, M_TEMP, M_WAITOK);
/* XXX: Horrible kludge to establish credentials for NFS */
aiov.iov_base = tmpbuf;
aiov.iov_len = min(DEV_BSIZE, dbtob(vn->sc_size));
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = 0;
auio.uio_rw = UIO_READ;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_resid = aiov.iov_len;
vn_lock(vn->sc_vp, LK_EXCLUSIVE | LK_RETRY, curproc);
error = VOP_READ(vn->sc_vp, &auio, 0, vn->sc_cred);
VOP_UNLOCK(vn->sc_vp, 0, curproc);
free(tmpbuf, M_TEMP);
return (error);
}
void
vnshutdown(int howto, void *ignored)
{
int i;
for (i = 0; i < NVN; i++)
if (vn_softc[i] && vn_softc[i]->sc_flags & VNF_INITED)
vnclear(vn_softc[i]);
}
void
vnclear(struct vn_softc *vn)
{
register struct vnode *vp = vn->sc_vp;
struct proc *p = curproc; /* XXX */
IFOPT(vn, VN_FOLLOW)
printf("vnclear(%p): vp=%p\n", vn, vp);
#ifdef SLICE
if (vn->slice->handler_up) {
(*(vn->slice->handler_up->revoke)) (vn->slice->private_up);
}
#else /* SLICE */
if (vn->sc_slices != NULL)
dsgone(&vn->sc_slices);
#endif
vn->sc_flags &= ~VNF_INITED;
if (vp == (struct vnode *)0)
panic("vnclear: null vp");
(void) vn_close(vp, FREAD|FWRITE, vn->sc_cred, p);
crfree(vn->sc_cred);
vn->sc_vp = (struct vnode *)0;
vn->sc_cred = (struct ucred *)0;
vn->sc_size = 0;
}
#ifndef SLICE
static int
vnsize(dev_t dev)
{
int unit = vnunit(dev);
if (unit >= NVN || (!vn_softc[unit]) ||
(vn_softc[unit]->sc_flags & VNF_INITED) == 0)
return(-1);
return(vn_softc[unit]->sc_size);
}
static int
vndump(dev_t dev)
{
return (ENODEV);
}
static vn_devsw_installed = 0;
#endif /* !SLICE */
static void
vn_drvinit(void *unused)
{
#ifndef SLICE
if( ! vn_devsw_installed ) {
if (at_shutdown(&vnshutdown, NULL, SHUTDOWN_POST_SYNC)) {
printf("vn: could not install shutdown hook\n");
return;
}
bdevsw_add_generic(BDEV_MAJOR, CDEV_MAJOR, &vn_bdevsw);
vn_devsw_installed = 1;
}
#else /* SLICE */
int mynor;
int unit;
struct vn_softc *vn;
char namebuf[64];
if (at_shutdown(&vnshutdown, NULL, SHUTDOWN_POST_SYNC)) {
printf("vn: could not install shutdown hook\n");
return;
}
for (unit = 0; unit < NVN; unit++) {
vn = malloc(sizeof *vn, M_DEVBUF, M_NOWAIT);
if (!vn)
return;
bzero(vn, sizeof *vn);
vn_softc[unit] = vn;
vn->unit = unit;
sprintf(namebuf,"vn%d",vn->unit);
vn->mynor = dkmakeminor(unit, WHOLE_DISK_SLICE,
RAW_PART);
vn->limit.blksize = DEV_BSIZE;
vn->limit.slicesize = ((u_int64_t)vn->sc_size * DEV_BSIZE);
sl_make_slice(&slicetype,
vn,
&vn->limit,
&vn->slice,
NULL,
namebuf);
/* Allow full probing */
vn->slice->probeinfo.typespecific = NULL;
vn->slice->probeinfo.type = NULL;
}
#endif /* SLICE */
}
SYSINIT(vndev, SI_SUB_DRIVERS, SI_ORDER_ANY, vn_drvinit, NULL)
#ifdef SLICE
static int
nvsopen(void *private, int flags, int mode, struct proc *p)
{
struct vn_softc *vn;
vn = private;
IFOPT(vn, VN_FOLLOW)
printf("vnopen(0x%lx, 0x%x, 0x%x, %p)\n",
makedev(0,vn->mynor) , flags, mode, p);
return (0);
}
#if 0
static void
nvsclose(void *private, int flags, int mode, struct proc *p)
{
struct vn_softc *vn;
vn = private;
IFOPT(vn, VN_FOLLOW)
printf("vnclose(0x%lx, 0x%x, 0x%x, %p)\n",
makedev(0,vn->mynor) , flags, mode, p);
return;
}
#endif
static int
nvsioctl( void *private, u_long cmd, caddr_t addr, int flag, struct proc *p)
{
struct vn_softc *vn;
vn = private;
return(vnioctl(makedev(0,vn->mynor), cmd, addr, flag, p));
}
static int
nvsdump(void *private, int32_t blkoff, int32_t blkcnt)
{
return (ENODEV);
}
#endif
#endif
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