efc68ce10f
Use bmap run-length extension when doing clustered paging. Submitted by: John Dyson
712 lines
17 KiB
C
712 lines
17 KiB
C
/*
|
|
* Copyright (c) 1989, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* 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.
|
|
*
|
|
* @(#)spec_vnops.c 8.6 (Berkeley) 4/9/94
|
|
* $Id: spec_vnops.c,v 1.9 1994/11/14 13:22:52 bde Exp $
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/buf.h>
|
|
#include <sys/mount.h>
|
|
#include <sys/namei.h>
|
|
#include <sys/vnode.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/errno.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/file.h>
|
|
#include <sys/disklabel.h>
|
|
#include <miscfs/specfs/specdev.h>
|
|
|
|
/* symbolic sleep message strings for devices */
|
|
char devopn[] = "devopn";
|
|
char devio[] = "devio";
|
|
char devwait[] = "devwait";
|
|
char devin[] = "devin";
|
|
char devout[] = "devout";
|
|
char devioc[] = "devioc";
|
|
char devcls[] = "devcls";
|
|
|
|
int (**spec_vnodeop_p)();
|
|
struct vnodeopv_entry_desc spec_vnodeop_entries[] = {
|
|
{ &vop_default_desc, vn_default_error },
|
|
{ &vop_lookup_desc, spec_lookup }, /* lookup */
|
|
{ &vop_create_desc, spec_create }, /* create */
|
|
{ &vop_mknod_desc, spec_mknod }, /* mknod */
|
|
{ &vop_open_desc, spec_open }, /* open */
|
|
{ &vop_close_desc, spec_close }, /* close */
|
|
{ &vop_access_desc, spec_access }, /* access */
|
|
{ &vop_getattr_desc, spec_getattr }, /* getattr */
|
|
{ &vop_setattr_desc, spec_setattr }, /* setattr */
|
|
{ &vop_read_desc, spec_read }, /* read */
|
|
{ &vop_write_desc, spec_write }, /* write */
|
|
{ &vop_ioctl_desc, spec_ioctl }, /* ioctl */
|
|
{ &vop_select_desc, spec_select }, /* select */
|
|
{ &vop_mmap_desc, spec_mmap }, /* mmap */
|
|
{ &vop_fsync_desc, spec_fsync }, /* fsync */
|
|
{ &vop_seek_desc, spec_seek }, /* seek */
|
|
{ &vop_remove_desc, spec_remove }, /* remove */
|
|
{ &vop_link_desc, spec_link }, /* link */
|
|
{ &vop_rename_desc, spec_rename }, /* rename */
|
|
{ &vop_mkdir_desc, spec_mkdir }, /* mkdir */
|
|
{ &vop_rmdir_desc, spec_rmdir }, /* rmdir */
|
|
{ &vop_symlink_desc, spec_symlink }, /* symlink */
|
|
{ &vop_readdir_desc, spec_readdir }, /* readdir */
|
|
{ &vop_readlink_desc, spec_readlink }, /* readlink */
|
|
{ &vop_abortop_desc, spec_abortop }, /* abortop */
|
|
{ &vop_inactive_desc, spec_inactive }, /* inactive */
|
|
{ &vop_reclaim_desc, spec_reclaim }, /* reclaim */
|
|
{ &vop_lock_desc, spec_lock }, /* lock */
|
|
{ &vop_unlock_desc, spec_unlock }, /* unlock */
|
|
{ &vop_bmap_desc, spec_bmap }, /* bmap */
|
|
{ &vop_strategy_desc, spec_strategy }, /* strategy */
|
|
{ &vop_print_desc, spec_print }, /* print */
|
|
{ &vop_islocked_desc, spec_islocked }, /* islocked */
|
|
{ &vop_pathconf_desc, spec_pathconf }, /* pathconf */
|
|
{ &vop_advlock_desc, spec_advlock }, /* advlock */
|
|
{ &vop_blkatoff_desc, spec_blkatoff }, /* blkatoff */
|
|
{ &vop_valloc_desc, spec_valloc }, /* valloc */
|
|
{ &vop_vfree_desc, spec_vfree }, /* vfree */
|
|
{ &vop_truncate_desc, spec_truncate }, /* truncate */
|
|
{ &vop_update_desc, spec_update }, /* update */
|
|
{ &vop_bwrite_desc, spec_bwrite }, /* bwrite */
|
|
{ (struct vnodeop_desc*)NULL, (int(*)())NULL }
|
|
};
|
|
struct vnodeopv_desc spec_vnodeop_opv_desc =
|
|
{ &spec_vnodeop_p, spec_vnodeop_entries };
|
|
|
|
VNODEOP_SET(spec_vnodeop_opv_desc);
|
|
|
|
/*
|
|
* Trivial lookup routine that always fails.
|
|
*/
|
|
int
|
|
spec_lookup(ap)
|
|
struct vop_lookup_args /* {
|
|
struct vnode *a_dvp;
|
|
struct vnode **a_vpp;
|
|
struct componentname *a_cnp;
|
|
} */ *ap;
|
|
{
|
|
|
|
*ap->a_vpp = NULL;
|
|
return (ENOTDIR);
|
|
}
|
|
|
|
/*
|
|
* Open a special file.
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
spec_open(ap)
|
|
struct vop_open_args /* {
|
|
struct vnode *a_vp;
|
|
int a_mode;
|
|
struct ucred *a_cred;
|
|
struct proc *a_p;
|
|
} */ *ap;
|
|
{
|
|
struct vnode *bvp, *vp = ap->a_vp;
|
|
dev_t bdev, dev = (dev_t)vp->v_rdev;
|
|
register int maj = major(dev);
|
|
int error;
|
|
|
|
/*
|
|
* Don't allow open if fs is mounted -nodev.
|
|
*/
|
|
if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV))
|
|
return (ENXIO);
|
|
|
|
switch (vp->v_type) {
|
|
|
|
case VCHR:
|
|
if ((u_int)maj >= nchrdev)
|
|
return (ENXIO);
|
|
if (ap->a_cred != FSCRED && (ap->a_mode & FWRITE)) {
|
|
/*
|
|
* When running in very secure mode, do not allow
|
|
* opens for writing of any disk character devices.
|
|
*/
|
|
if (securelevel >= 2 && isdisk(dev, VCHR))
|
|
return (EPERM);
|
|
/*
|
|
* When running in secure mode, do not allow opens
|
|
* for writing of /dev/mem, /dev/kmem, or character
|
|
* devices whose corresponding block devices are
|
|
* currently mounted.
|
|
*/
|
|
if (securelevel >= 1) {
|
|
if ((bdev = chrtoblk(dev)) != NODEV &&
|
|
vfinddev(bdev, VBLK, &bvp) &&
|
|
bvp->v_usecount > 0 &&
|
|
(error = vfs_mountedon(bvp)))
|
|
return (error);
|
|
if (iskmemdev(dev))
|
|
return (EPERM);
|
|
}
|
|
}
|
|
VOP_UNLOCK(vp);
|
|
error = (*cdevsw[maj].d_open)(dev, ap->a_mode, S_IFCHR, ap->a_p);
|
|
VOP_LOCK(vp);
|
|
return (error);
|
|
|
|
case VBLK:
|
|
if ((u_int)maj >= nblkdev)
|
|
return (ENXIO);
|
|
/*
|
|
* When running in very secure mode, do not allow
|
|
* opens for writing of any disk block devices.
|
|
*/
|
|
if (securelevel >= 2 && ap->a_cred != FSCRED &&
|
|
(ap->a_mode & FWRITE) && isdisk(dev, VBLK))
|
|
return (EPERM);
|
|
/*
|
|
* Do not allow opens of block devices that are
|
|
* currently mounted.
|
|
*/
|
|
error = vfs_mountedon(vp);
|
|
if (error)
|
|
return (error);
|
|
return ((*bdevsw[maj].d_open)(dev, ap->a_mode, S_IFBLK, ap->a_p));
|
|
default:
|
|
break;
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Vnode op for read
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
spec_read(ap)
|
|
struct vop_read_args /* {
|
|
struct vnode *a_vp;
|
|
struct uio *a_uio;
|
|
int a_ioflag;
|
|
struct ucred *a_cred;
|
|
} */ *ap;
|
|
{
|
|
register struct vnode *vp = ap->a_vp;
|
|
register struct uio *uio = ap->a_uio;
|
|
struct proc *p = uio->uio_procp;
|
|
struct buf *bp;
|
|
daddr_t bn, nextbn;
|
|
long bsize, bscale;
|
|
struct partinfo dpart;
|
|
int n, on, majordev, (*ioctl)();
|
|
int error = 0;
|
|
dev_t dev;
|
|
|
|
#ifdef DIAGNOSTIC
|
|
if (uio->uio_rw != UIO_READ)
|
|
panic("spec_read mode");
|
|
if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
|
|
panic("spec_read proc");
|
|
#endif
|
|
if (uio->uio_resid == 0)
|
|
return (0);
|
|
|
|
switch (vp->v_type) {
|
|
|
|
case VCHR:
|
|
VOP_UNLOCK(vp);
|
|
error = (*cdevsw[major(vp->v_rdev)].d_read)
|
|
(vp->v_rdev, uio, ap->a_ioflag);
|
|
VOP_LOCK(vp);
|
|
return (error);
|
|
|
|
case VBLK:
|
|
if (uio->uio_offset < 0)
|
|
return (EINVAL);
|
|
bsize = BLKDEV_IOSIZE;
|
|
dev = vp->v_rdev;
|
|
if ((majordev = major(dev)) < nblkdev &&
|
|
(ioctl = bdevsw[majordev].d_ioctl) != NULL &&
|
|
(*ioctl)(dev, DIOCGPART, (caddr_t)&dpart, FREAD, p) == 0 &&
|
|
dpart.part->p_fstype == FS_BSDFFS &&
|
|
dpart.part->p_frag != 0 && dpart.part->p_fsize != 0)
|
|
bsize = dpart.part->p_frag * dpart.part->p_fsize;
|
|
bscale = bsize / DEV_BSIZE;
|
|
do {
|
|
bn = (uio->uio_offset / DEV_BSIZE) &~ (bscale - 1);
|
|
on = uio->uio_offset % bsize;
|
|
n = min((unsigned)(bsize - on), uio->uio_resid);
|
|
if (vp->v_lastr + bscale == bn) {
|
|
nextbn = bn + bscale;
|
|
error = breadn(vp, bn, (int)bsize, &nextbn,
|
|
(int *)&bsize, 1, NOCRED, &bp);
|
|
} else
|
|
error = bread(vp, bn, (int)bsize, NOCRED, &bp);
|
|
vp->v_lastr = bn;
|
|
n = min(n, bsize - bp->b_resid);
|
|
if (error) {
|
|
brelse(bp);
|
|
return (error);
|
|
}
|
|
error = uiomove((char *)bp->b_data + on, n, uio);
|
|
brelse(bp);
|
|
} while (error == 0 && uio->uio_resid > 0 && n != 0);
|
|
return (error);
|
|
|
|
default:
|
|
panic("spec_read type");
|
|
}
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
/*
|
|
* Vnode op for write
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
spec_write(ap)
|
|
struct vop_write_args /* {
|
|
struct vnode *a_vp;
|
|
struct uio *a_uio;
|
|
int a_ioflag;
|
|
struct ucred *a_cred;
|
|
} */ *ap;
|
|
{
|
|
register struct vnode *vp = ap->a_vp;
|
|
register struct uio *uio = ap->a_uio;
|
|
struct proc *p = uio->uio_procp;
|
|
struct buf *bp;
|
|
daddr_t bn;
|
|
int bsize, blkmask;
|
|
struct partinfo dpart;
|
|
register int n, on;
|
|
int error = 0;
|
|
|
|
#ifdef DIAGNOSTIC
|
|
if (uio->uio_rw != UIO_WRITE)
|
|
panic("spec_write mode");
|
|
if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
|
|
panic("spec_write proc");
|
|
#endif
|
|
|
|
switch (vp->v_type) {
|
|
|
|
case VCHR:
|
|
VOP_UNLOCK(vp);
|
|
error = (*cdevsw[major(vp->v_rdev)].d_write)
|
|
(vp->v_rdev, uio, ap->a_ioflag);
|
|
VOP_LOCK(vp);
|
|
return (error);
|
|
|
|
case VBLK:
|
|
if (uio->uio_resid == 0)
|
|
return (0);
|
|
if (uio->uio_offset < 0)
|
|
return (EINVAL);
|
|
bsize = BLKDEV_IOSIZE;
|
|
if ((*bdevsw[major(vp->v_rdev)].d_ioctl)(vp->v_rdev, DIOCGPART,
|
|
(caddr_t)&dpart, FREAD, p) == 0) {
|
|
if (dpart.part->p_fstype == FS_BSDFFS &&
|
|
dpart.part->p_frag != 0 && dpart.part->p_fsize != 0)
|
|
bsize = dpart.part->p_frag *
|
|
dpart.part->p_fsize;
|
|
}
|
|
blkmask = (bsize / DEV_BSIZE) - 1;
|
|
do {
|
|
bn = (uio->uio_offset / DEV_BSIZE) &~ blkmask;
|
|
on = uio->uio_offset % bsize;
|
|
n = min((unsigned)(bsize - on), uio->uio_resid);
|
|
if (n == bsize)
|
|
bp = getblk(vp, bn, bsize, 0, 0);
|
|
else
|
|
error = bread(vp, bn, bsize, NOCRED, &bp);
|
|
n = min(n, bsize - bp->b_resid);
|
|
if (error) {
|
|
brelse(bp);
|
|
return (error);
|
|
}
|
|
error = uiomove((char *)bp->b_data + on, n, uio);
|
|
if (n + on == bsize) {
|
|
bawrite(bp);
|
|
} else
|
|
bdwrite(bp);
|
|
} while (error == 0 && uio->uio_resid > 0 && n != 0);
|
|
return (error);
|
|
|
|
default:
|
|
panic("spec_write type");
|
|
}
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
/*
|
|
* Device ioctl operation.
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
spec_ioctl(ap)
|
|
struct vop_ioctl_args /* {
|
|
struct vnode *a_vp;
|
|
int a_command;
|
|
caddr_t a_data;
|
|
int a_fflag;
|
|
struct ucred *a_cred;
|
|
struct proc *a_p;
|
|
} */ *ap;
|
|
{
|
|
dev_t dev = ap->a_vp->v_rdev;
|
|
|
|
switch (ap->a_vp->v_type) {
|
|
|
|
case VCHR:
|
|
return ((*cdevsw[major(dev)].d_ioctl)(dev, ap->a_command, ap->a_data,
|
|
ap->a_fflag, ap->a_p));
|
|
|
|
case VBLK:
|
|
if (ap->a_command == 0 && (int)ap->a_data == B_TAPE)
|
|
if (bdevsw[major(dev)].d_flags & B_TAPE)
|
|
return (0);
|
|
else
|
|
return (1);
|
|
return ((*bdevsw[major(dev)].d_ioctl)(dev, ap->a_command, ap->a_data,
|
|
ap->a_fflag, ap->a_p));
|
|
|
|
default:
|
|
panic("spec_ioctl");
|
|
/* NOTREACHED */
|
|
}
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
int
|
|
spec_select(ap)
|
|
struct vop_select_args /* {
|
|
struct vnode *a_vp;
|
|
int a_which;
|
|
int a_fflags;
|
|
struct ucred *a_cred;
|
|
struct proc *a_p;
|
|
} */ *ap;
|
|
{
|
|
register dev_t dev;
|
|
|
|
switch (ap->a_vp->v_type) {
|
|
|
|
default:
|
|
return (1); /* XXX */
|
|
|
|
case VCHR:
|
|
dev = ap->a_vp->v_rdev;
|
|
return (*cdevsw[major(dev)].d_select)(dev, ap->a_which, ap->a_p);
|
|
}
|
|
}
|
|
/*
|
|
* Synch buffers associated with a block device
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
spec_fsync(ap)
|
|
struct vop_fsync_args /* {
|
|
struct vnode *a_vp;
|
|
struct ucred *a_cred;
|
|
int a_waitfor;
|
|
struct proc *a_p;
|
|
} */ *ap;
|
|
{
|
|
register struct vnode *vp = ap->a_vp;
|
|
register struct buf *bp;
|
|
struct buf *nbp;
|
|
int s;
|
|
|
|
if (vp->v_type == VCHR)
|
|
return (0);
|
|
/*
|
|
* Flush all dirty buffers associated with a block device.
|
|
*/
|
|
loop:
|
|
s = splbio();
|
|
for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) {
|
|
nbp = bp->b_vnbufs.le_next;
|
|
if ((bp->b_flags & B_BUSY))
|
|
continue;
|
|
if ((bp->b_flags & B_DELWRI) == 0)
|
|
panic("spec_fsync: not dirty");
|
|
bremfree(bp);
|
|
bp->b_flags |= B_BUSY;
|
|
splx(s);
|
|
bawrite(bp);
|
|
goto loop;
|
|
}
|
|
if (ap->a_waitfor == MNT_WAIT) {
|
|
while (vp->v_numoutput) {
|
|
vp->v_flag |= VBWAIT;
|
|
(void) tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "spfsyn", 0);
|
|
}
|
|
#ifdef DIAGNOSTIC
|
|
if (vp->v_dirtyblkhd.lh_first) {
|
|
vprint("spec_fsync: dirty", vp);
|
|
goto loop;
|
|
}
|
|
#endif
|
|
}
|
|
splx(s);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Just call the device strategy routine
|
|
*/
|
|
int
|
|
spec_strategy(ap)
|
|
struct vop_strategy_args /* {
|
|
struct buf *a_bp;
|
|
} */ *ap;
|
|
{
|
|
|
|
(*bdevsw[major(ap->a_bp->b_dev)].d_strategy)(ap->a_bp);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* This is a noop, simply returning what one has been given.
|
|
*/
|
|
int
|
|
spec_bmap(ap)
|
|
struct vop_bmap_args /* {
|
|
struct vnode *a_vp;
|
|
daddr_t a_bn;
|
|
struct vnode **a_vpp;
|
|
daddr_t *a_bnp;
|
|
} */ *ap;
|
|
{
|
|
|
|
if (ap->a_vpp != NULL)
|
|
*ap->a_vpp = ap->a_vp;
|
|
if (ap->a_bnp != NULL)
|
|
*ap->a_bnp = ap->a_bn;
|
|
if (ap->a_runp != NULL)
|
|
*ap->a_runp = 0;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* At the moment we do not do any locking.
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
spec_lock(ap)
|
|
struct vop_lock_args /* {
|
|
struct vnode *a_vp;
|
|
} */ *ap;
|
|
{
|
|
|
|
return (0);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
int
|
|
spec_unlock(ap)
|
|
struct vop_unlock_args /* {
|
|
struct vnode *a_vp;
|
|
} */ *ap;
|
|
{
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Device close routine
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
spec_close(ap)
|
|
struct vop_close_args /* {
|
|
struct vnode *a_vp;
|
|
int a_fflag;
|
|
struct ucred *a_cred;
|
|
struct proc *a_p;
|
|
} */ *ap;
|
|
{
|
|
register struct vnode *vp = ap->a_vp;
|
|
dev_t dev = vp->v_rdev;
|
|
int (*devclose) __P((dev_t, int, int, struct proc *));
|
|
int mode, error;
|
|
|
|
switch (vp->v_type) {
|
|
|
|
case VCHR:
|
|
/*
|
|
* Hack: a tty device that is a controlling terminal
|
|
* has a reference from the session structure.
|
|
* We cannot easily tell that a character device is
|
|
* a controlling terminal, unless it is the closing
|
|
* process' controlling terminal. In that case,
|
|
* if the reference count is 2 (this last descriptor
|
|
* plus the session), release the reference from the session.
|
|
*/
|
|
if (vcount(vp) == 2 && ap->a_p &&
|
|
vp == ap->a_p->p_session->s_ttyvp) {
|
|
vrele(vp);
|
|
ap->a_p->p_session->s_ttyvp = NULL;
|
|
}
|
|
/*
|
|
* If the vnode is locked, then we are in the midst
|
|
* of forcably closing the device, otherwise we only
|
|
* close on last reference.
|
|
*/
|
|
if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0)
|
|
return (0);
|
|
devclose = cdevsw[major(dev)].d_close;
|
|
mode = S_IFCHR;
|
|
break;
|
|
|
|
case VBLK:
|
|
/*
|
|
* On last close of a block device (that isn't mounted)
|
|
* we must invalidate any in core blocks, so that
|
|
* we can, for instance, change floppy disks.
|
|
*/
|
|
error = vinvalbuf(vp, V_SAVE, ap->a_cred, ap->a_p, 0, 0);
|
|
if (error)
|
|
return (error);
|
|
/*
|
|
* We do not want to really close the device if it
|
|
* is still in use unless we are trying to close it
|
|
* forcibly. Since every use (buffer, vnode, swap, cmap)
|
|
* holds a reference to the vnode, and because we mark
|
|
* any other vnodes that alias this device, when the
|
|
* sum of the reference counts on all the aliased
|
|
* vnodes descends to one, we are on last close.
|
|
*/
|
|
if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0)
|
|
return (0);
|
|
devclose = bdevsw[major(dev)].d_close;
|
|
mode = S_IFBLK;
|
|
break;
|
|
|
|
default:
|
|
panic("spec_close: not special");
|
|
}
|
|
|
|
return ((*devclose)(dev, ap->a_fflag, mode, ap->a_p));
|
|
}
|
|
|
|
/*
|
|
* Print out the contents of a special device vnode.
|
|
*/
|
|
int
|
|
spec_print(ap)
|
|
struct vop_print_args /* {
|
|
struct vnode *a_vp;
|
|
} */ *ap;
|
|
{
|
|
|
|
printf("tag VT_NON, dev %d, %d\n", major(ap->a_vp->v_rdev),
|
|
minor(ap->a_vp->v_rdev));
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Return POSIX pathconf information applicable to special devices.
|
|
*/
|
|
int
|
|
spec_pathconf(ap)
|
|
struct vop_pathconf_args /* {
|
|
struct vnode *a_vp;
|
|
int a_name;
|
|
int *a_retval;
|
|
} */ *ap;
|
|
{
|
|
|
|
switch (ap->a_name) {
|
|
case _PC_LINK_MAX:
|
|
*ap->a_retval = LINK_MAX;
|
|
return (0);
|
|
case _PC_MAX_CANON:
|
|
*ap->a_retval = MAX_CANON;
|
|
return (0);
|
|
case _PC_MAX_INPUT:
|
|
*ap->a_retval = MAX_INPUT;
|
|
return (0);
|
|
case _PC_PIPE_BUF:
|
|
*ap->a_retval = PIPE_BUF;
|
|
return (0);
|
|
case _PC_CHOWN_RESTRICTED:
|
|
*ap->a_retval = 1;
|
|
return (0);
|
|
case _PC_VDISABLE:
|
|
*ap->a_retval = _POSIX_VDISABLE;
|
|
return (0);
|
|
default:
|
|
return (EINVAL);
|
|
}
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
/*
|
|
* Special device advisory byte-level locks.
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
spec_advlock(ap)
|
|
struct vop_advlock_args /* {
|
|
struct vnode *a_vp;
|
|
caddr_t a_id;
|
|
int a_op;
|
|
struct flock *a_fl;
|
|
int a_flags;
|
|
} */ *ap;
|
|
{
|
|
|
|
return (EOPNOTSUPP);
|
|
}
|
|
|
|
/*
|
|
* Special device failed operation
|
|
*/
|
|
int
|
|
spec_ebadf()
|
|
{
|
|
|
|
return (EBADF);
|
|
}
|
|
|
|
/*
|
|
* Special device bad operation
|
|
*/
|
|
int
|
|
spec_badop()
|
|
{
|
|
|
|
panic("spec_badop called");
|
|
/* NOTREACHED */
|
|
}
|