718 lines
17 KiB
C
718 lines
17 KiB
C
/*
|
|
* 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
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
/*
|
|
* 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"
|
|
|
|
#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/conf.h>
|
|
#include <sys/disklabel.h>
|
|
#include <sys/diskslice.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/module.h>
|
|
#include <sys/vnioctl.h>
|
|
|
|
#include <vm/vm.h>
|
|
#include <vm/vm_prot.h>
|
|
#include <vm/vm_object.h>
|
|
#include <vm/vm_page.h>
|
|
#include <vm/vm_pager.h>
|
|
#include <vm/vm_pageout.h>
|
|
#include <vm/swap_pager.h>
|
|
#include <vm/vm_extern.h>
|
|
#include <vm/vm_zone.h>
|
|
|
|
static d_ioctl_t vnioctl;
|
|
static d_open_t vnopen;
|
|
static d_close_t vnclose;
|
|
static d_psize_t vnsize;
|
|
static d_strategy_t vnstrategy;
|
|
|
|
#define CDEV_MAJOR 43
|
|
#define BDEV_MAJOR 15
|
|
|
|
/*
|
|
* cdevsw
|
|
* D_DISK we want to look like a disk
|
|
* ( D_NOCLUSTERRW removed - clustering should be ok )
|
|
* D_CANFREE We support B_FREEBUF
|
|
*/
|
|
|
|
static struct cdevsw vn_cdevsw = {
|
|
/* open */ vnopen,
|
|
/* close */ vnclose,
|
|
/* read */ physread,
|
|
/* write */ physwrite,
|
|
/* ioctl */ vnioctl,
|
|
/* stop */ nostop,
|
|
/* reset */ noreset,
|
|
/* devtotty */ nodevtotty,
|
|
/* poll */ nopoll,
|
|
/* mmap */ nommap,
|
|
/* strategy */ vnstrategy,
|
|
/* name */ "vn",
|
|
/* parms */ noparms,
|
|
/* maj */ CDEV_MAJOR,
|
|
/* dump */ nodump,
|
|
/* psize */ vnsize,
|
|
/* flags */ D_DISK|D_CANFREE,
|
|
/* maxio */ 0,
|
|
/* bmaj */ BDEV_MAJOR
|
|
};
|
|
|
|
#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_unit;
|
|
int sc_flags; /* flags */
|
|
int sc_size; /* size of vn, sc_secsize scale */
|
|
int sc_secsize; /* sector size */
|
|
struct diskslices *sc_slices;
|
|
struct vnode *sc_vp; /* vnode if not NULL */
|
|
vm_object_t sc_object; /* backing object if not NULL */
|
|
struct ucred *sc_cred; /* credentials */
|
|
int sc_maxactive; /* max # of active requests */
|
|
struct buf sc_tab; /* transfer queue */
|
|
u_long sc_options; /* options */
|
|
SLIST_ENTRY(vn_softc) sc_list;
|
|
};
|
|
|
|
static SLIST_HEAD(, vn_softc) vn_list;
|
|
|
|
/* sc_flags */
|
|
#define VNF_INITED 0x01
|
|
#define VNF_READONLY 0x02
|
|
|
|
static u_long vn_options;
|
|
|
|
#define IFOPT(vn,opt) if (((vn)->sc_options|vn_options) & (opt))
|
|
|
|
static int vnsetcred (struct vn_softc *vn, struct ucred *cred);
|
|
static void vnclear (struct vn_softc *vn);
|
|
static int vn_modevent (module_t, int, void *);
|
|
static int vniocattach_file (struct vn_softc *, struct vn_ioctl *, dev_t dev, int flag, struct proc *p);
|
|
static int vniocattach_swap (struct vn_softc *, struct vn_ioctl *, dev_t dev, int flag, struct proc *p);
|
|
|
|
static int
|
|
vnclose(dev_t dev, int flags, int mode, struct proc *p)
|
|
{
|
|
struct vn_softc *vn = dev->si_drv1;
|
|
|
|
IFOPT(vn, VN_LABELS)
|
|
if (vn->sc_slices != NULL)
|
|
dsclose(dev, mode, vn->sc_slices);
|
|
return (0);
|
|
}
|
|
|
|
static struct vn_softc *
|
|
vnfindvn(dev_t dev)
|
|
{
|
|
int unit;
|
|
struct vn_softc *vn;
|
|
|
|
unit = dkunit(dev);
|
|
vn = dev->si_drv1;
|
|
if (!vn) {
|
|
SLIST_FOREACH(vn, &vn_list, sc_list) {
|
|
if (vn->sc_unit == unit) {
|
|
dev->si_drv1 = vn;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (!vn) {
|
|
vn = malloc(sizeof *vn, M_DEVBUF, M_WAITOK);
|
|
if (!vn)
|
|
return (NULL);
|
|
bzero(vn, sizeof *vn);
|
|
vn->sc_unit = unit;
|
|
dev->si_drv1 = vn;
|
|
make_dev(&vn_cdevsw, 0,
|
|
UID_ROOT, GID_OPERATOR, 0640, "vn%d", unit);
|
|
SLIST_INSERT_HEAD(&vn_list, vn, sc_list);
|
|
}
|
|
return (vn);
|
|
}
|
|
|
|
static int
|
|
vnopen(dev_t dev, int flags, int mode, struct proc *p)
|
|
{
|
|
int unit;
|
|
struct vn_softc *vn;
|
|
|
|
unit = dkunit(dev);
|
|
vn = dev->si_drv1;
|
|
if (!vn)
|
|
vn = vnfindvn(dev);
|
|
|
|
if (flags & FWRITE && vn->sc_flags & VNF_READONLY)
|
|
return (EACCES);
|
|
|
|
IFOPT(vn, VN_FOLLOW)
|
|
printf("vnopen(%s, 0x%x, 0x%x, %p)\n",
|
|
devtoname(dev), flags, mode, (void *)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 = vn->sc_secsize;
|
|
label.d_nsectors = 32;
|
|
label.d_ntracks = 64 / (vn->sc_secsize / DEV_BSIZE);
|
|
label.d_secpercyl = label.d_nsectors * label.d_ntracks;
|
|
label.d_ncylinders = vn->sc_size / label.d_secpercyl;
|
|
label.d_secperunit = vn->sc_size;
|
|
label.d_partitions[RAW_PART].p_size = vn->sc_size;
|
|
|
|
return (dsopen(dev, mode, 0, &vn->sc_slices, &label));
|
|
}
|
|
if (dkslice(dev) != WHOLE_DISK_SLICE ||
|
|
dkpart(dev) != RAW_PART ||
|
|
mode != S_IFCHR)
|
|
return (ENXIO);
|
|
}
|
|
return(0);
|
|
}
|
|
|
|
/*
|
|
* vnstrategy:
|
|
*
|
|
* Run strategy routine for VN device. We use VOP_READ/VOP_WRITE calls
|
|
* for vnode-backed vn's, and the new vm_pager_strategy() call for
|
|
* vm_object-backed vn's.
|
|
*
|
|
* Currently B_ASYNC is only partially handled - for OBJT_SWAP I/O only.
|
|
*
|
|
* NOTE: bp->b_blkno is DEV_BSIZE'd. We must generate bp->b_pblkno for
|
|
* our uio or vn_pager_strategy() call that is vn->sc_secsize'd
|
|
*/
|
|
|
|
static void
|
|
vnstrategy(struct buf *bp)
|
|
{
|
|
int unit;
|
|
struct vn_softc *vn;
|
|
int error;
|
|
int isvplocked = 0;
|
|
long sz;
|
|
struct uio auio;
|
|
struct iovec aiov;
|
|
|
|
unit = dkunit(bp->b_dev);
|
|
vn = bp->b_dev->si_drv1;
|
|
if (!vn)
|
|
vn = vnfindvn(bp->b_dev);
|
|
|
|
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;
|
|
}
|
|
|
|
bp->b_resid = bp->b_bcount;
|
|
|
|
IFOPT(vn, VN_LABELS) {
|
|
if (vn->sc_slices != NULL && dscheck(bp, vn->sc_slices) <= 0) {
|
|
bp->b_flags |= B_INVAL;
|
|
biodone(bp);
|
|
return;
|
|
}
|
|
} else {
|
|
int pbn;
|
|
|
|
pbn = bp->b_blkno * (vn->sc_secsize / DEV_BSIZE);
|
|
sz = howmany(bp->b_bcount, vn->sc_secsize);
|
|
|
|
if (pbn < 0 || pbn + sz > vn->sc_size) {
|
|
if (pbn != vn->sc_size) {
|
|
bp->b_error = EINVAL;
|
|
bp->b_flags |= B_ERROR | B_INVAL;
|
|
}
|
|
biodone(bp);
|
|
return;
|
|
}
|
|
bp->b_pblkno = pbn;
|
|
}
|
|
|
|
if (vn->sc_vp && (bp->b_flags & B_FREEBUF)) {
|
|
/*
|
|
* Not handled for vnode-backed element yet.
|
|
*/
|
|
biodone(bp);
|
|
} else if (vn->sc_vp) {
|
|
/*
|
|
* VNODE I/O
|
|
*/
|
|
aiov.iov_base = bp->b_data;
|
|
aiov.iov_len = bp->b_bcount;
|
|
auio.uio_iov = &aiov;
|
|
auio.uio_iovcnt = 1;
|
|
auio.uio_offset = (vm_ooffset_t)bp->b_pblkno * vn->sc_secsize;
|
|
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_error = error;
|
|
bp->b_flags |= B_ERROR;
|
|
}
|
|
biodone(bp);
|
|
} else if (vn->sc_object) {
|
|
/*
|
|
* OBJT_SWAP I/O
|
|
*
|
|
* ( handles read, write, freebuf )
|
|
*/
|
|
vm_pager_strategy(vn->sc_object, bp);
|
|
} else {
|
|
bp->b_flags |= B_ERROR;
|
|
bp->b_error = EINVAL;
|
|
biodone(bp);
|
|
}
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static int
|
|
vnioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
|
|
{
|
|
struct vn_softc *vn;
|
|
struct vn_ioctl *vio;
|
|
int error;
|
|
u_long *f;
|
|
|
|
vn = dev->si_drv1;
|
|
IFOPT(vn,VN_FOLLOW)
|
|
printf("vnioctl(%s, 0x%lx, %p, 0x%x, %p): unit %d\n",
|
|
devtoname(dev), cmd, (void *)data, flag, (void *)p,
|
|
dkunit(dev));
|
|
|
|
switch (cmd) {
|
|
case VNIOCATTACH:
|
|
case VNIOCDETACH:
|
|
case VNIOCGSET:
|
|
case VNIOCGCLEAR:
|
|
case VNIOCUSET:
|
|
case VNIOCUCLEAR:
|
|
goto vn_specific;
|
|
}
|
|
|
|
IFOPT(vn,VN_LABELS) {
|
|
if (vn->sc_slices != NULL) {
|
|
error = dsioctl(dev, cmd, data, flag, &vn->sc_slices);
|
|
if (error != ENOIOCTL)
|
|
return (error);
|
|
}
|
|
if (dkslice(dev) != WHOLE_DISK_SLICE ||
|
|
dkpart(dev) != RAW_PART)
|
|
return (ENOTTY);
|
|
}
|
|
|
|
vn_specific:
|
|
|
|
error = suser(p);
|
|
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);
|
|
|
|
if (vio->vn_file == NULL)
|
|
error = vniocattach_swap(vn, vio, dev, flag, p);
|
|
else
|
|
error = vniocattach_file(vn, vio, dev, flag, p);
|
|
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? (Hint: They are not)
|
|
*/
|
|
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:
|
|
error = ENOTTY;
|
|
break;
|
|
}
|
|
return(error);
|
|
}
|
|
|
|
/*
|
|
* vniocattach_file:
|
|
*
|
|
* Attach a file to a VN partition. Return the size in the vn_size
|
|
* field.
|
|
*/
|
|
|
|
static int
|
|
vniocattach_file(vn, vio, dev, flag, p)
|
|
struct vn_softc *vn;
|
|
struct vn_ioctl *vio;
|
|
dev_t dev;
|
|
int flag;
|
|
struct proc *p;
|
|
{
|
|
struct vattr vattr;
|
|
struct nameidata nd;
|
|
int error, flags;
|
|
|
|
flags = FREAD|FWRITE;
|
|
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, vio->vn_file, p);
|
|
error = vn_open(&nd, flags, 0);
|
|
if (error) {
|
|
if (error != EACCES && error != EPERM && error != EROFS)
|
|
return (error);
|
|
flags &= ~FWRITE;
|
|
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, vio->vn_file, p);
|
|
error = vn_open(&nd, flags, 0);
|
|
if (error)
|
|
return (error);
|
|
}
|
|
if (nd.ni_vp->v_type != VREG ||
|
|
(error = VOP_GETATTR(nd.ni_vp, &vattr, p->p_ucred, p))) {
|
|
VOP_UNLOCK(nd.ni_vp, 0, p);
|
|
(void) vn_close(nd.ni_vp, flags, p->p_ucred, p);
|
|
return (error ? error : EINVAL);
|
|
}
|
|
VOP_UNLOCK(nd.ni_vp, 0, p);
|
|
vn->sc_secsize = DEV_BSIZE;
|
|
vn->sc_vp = nd.ni_vp;
|
|
vn->sc_size = vattr.va_size / vn->sc_secsize; /* note truncation */
|
|
error = vnsetcred(vn, p->p_ucred);
|
|
if (error) {
|
|
(void) vn_close(nd.ni_vp, flags, p->p_ucred, p);
|
|
return(error);
|
|
}
|
|
if (dev->si_bsize_phys < vn->sc_secsize)
|
|
dev->si_bsize_phys = vn->sc_secsize;
|
|
if (dev->si_bsize_best < vn->sc_secsize)
|
|
dev->si_bsize_best = vn->sc_secsize;
|
|
vn->sc_flags |= VNF_INITED;
|
|
if (flags == FREAD)
|
|
vn->sc_flags |= VNF_READONLY;
|
|
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);
|
|
}
|
|
IFOPT(vn, VN_FOLLOW)
|
|
printf("vnioctl: SET vp %p size %x blks\n",
|
|
vn->sc_vp, vn->sc_size);
|
|
return(0);
|
|
}
|
|
|
|
/*
|
|
* vniocattach_swap:
|
|
*
|
|
* Attach swap backing store to a VN partition of the size specified
|
|
* in vn_size.
|
|
*/
|
|
|
|
static int
|
|
vniocattach_swap(vn, vio, dev, flag, p)
|
|
struct vn_softc *vn;
|
|
struct vn_ioctl *vio;
|
|
dev_t dev;
|
|
int flag;
|
|
struct proc *p;
|
|
{
|
|
int error;
|
|
|
|
/*
|
|
* Range check. Disallow negative sizes or any size less then the
|
|
* size of a page. Then round to a page.
|
|
*/
|
|
|
|
if (vio->vn_size <= 0)
|
|
return(EDOM);
|
|
|
|
/*
|
|
* Allocate an OBJT_SWAP object.
|
|
*
|
|
* sc_secsize is PAGE_SIZE'd
|
|
*
|
|
* vio->vn_size is in PAGE_SIZE'd chunks.
|
|
* sc_size must be in PAGE_SIZE'd chunks.
|
|
* Note the truncation.
|
|
*/
|
|
|
|
vn->sc_secsize = PAGE_SIZE;
|
|
vn->sc_size = vio->vn_size;
|
|
vn->sc_object =
|
|
vm_pager_allocate(OBJT_SWAP, NULL, vn->sc_secsize * (vm_ooffset_t)vio->vn_size, VM_PROT_DEFAULT, 0);
|
|
vn->sc_flags |= VNF_INITED;
|
|
|
|
error = vnsetcred(vn, p->p_ucred);
|
|
if (error == 0) {
|
|
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 == 0) {
|
|
IFOPT(vn, VN_FOLLOW) {
|
|
printf("vnioctl: SET vp %p size %x\n",
|
|
vn->sc_vp, vn->sc_size);
|
|
}
|
|
}
|
|
if (error)
|
|
vnclear(vn);
|
|
return(error);
|
|
}
|
|
|
|
/*
|
|
* 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 = 0;
|
|
|
|
/*
|
|
* Set credits in our softc
|
|
*/
|
|
|
|
if (vn->sc_cred)
|
|
crfree(vn->sc_cred);
|
|
vn->sc_cred = crdup(cred);
|
|
|
|
/*
|
|
* Horrible kludge to establish credentials for NFS XXX.
|
|
*/
|
|
|
|
if (vn->sc_vp) {
|
|
tmpbuf = malloc(vn->sc_secsize, M_TEMP, M_WAITOK);
|
|
|
|
aiov.iov_base = tmpbuf;
|
|
aiov.iov_len = vn->sc_secsize;
|
|
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
|
|
vnclear(struct vn_softc *vn)
|
|
{
|
|
struct proc *p = curproc; /* XXX */
|
|
|
|
IFOPT(vn, VN_FOLLOW)
|
|
printf("vnclear(%p): vp=%p\n", vn, vn->sc_vp);
|
|
if (vn->sc_slices != NULL)
|
|
dsgone(&vn->sc_slices);
|
|
vn->sc_flags &= ~VNF_INITED;
|
|
if (vn->sc_vp != NULL) {
|
|
(void)vn_close(vn->sc_vp, vn->sc_flags & VNF_READONLY ?
|
|
FREAD : (FREAD|FWRITE), vn->sc_cred, p);
|
|
vn->sc_vp = NULL;
|
|
}
|
|
vn->sc_flags &= ~VNF_READONLY;
|
|
if (vn->sc_cred) {
|
|
crfree(vn->sc_cred);
|
|
vn->sc_cred = NULL;
|
|
}
|
|
if (vn->sc_object != NULL) {
|
|
vm_pager_deallocate(vn->sc_object);
|
|
vn->sc_object = NULL;
|
|
}
|
|
vn->sc_size = 0;
|
|
}
|
|
|
|
static int
|
|
vnsize(dev_t dev)
|
|
{
|
|
struct vn_softc *vn;
|
|
|
|
vn = dev->si_drv1;
|
|
if (!vn)
|
|
return(-1);
|
|
if ((vn->sc_flags & VNF_INITED) == 0)
|
|
return(-1);
|
|
|
|
return(vn->sc_size);
|
|
}
|
|
|
|
static int
|
|
vn_modevent(module_t mod, int type, void *data)
|
|
{
|
|
struct vn_softc *vn;
|
|
|
|
switch (type) {
|
|
case MOD_LOAD:
|
|
break;
|
|
|
|
case MOD_UNLOAD:
|
|
/* fall through */
|
|
case MOD_SHUTDOWN:
|
|
for (;;) {
|
|
vn = SLIST_FIRST(&vn_list);
|
|
if (!vn)
|
|
break;
|
|
SLIST_REMOVE_HEAD(&vn_list, sc_list);
|
|
if (vn->sc_flags & VNF_INITED)
|
|
vnclear(vn);
|
|
free(vn, M_DEVBUF);
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
DEV_MODULE(vn, CDEV_MAJOR, BDEV_MAJOR, vn_cdevsw, vn_modevent, 0);
|