Source to bsd/miscfs/specfs/spec_vnops.c
/*
* Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* "Portions Copyright (c) 1999 Apple Computer, Inc. All Rights
* Reserved. This file contains Original Code and/or Modifications of
* Original Code as defined in and that are subject to the Apple Public
* Source License Version 1.0 (the 'License'). You may not use this file
* except in compliance with the License. Please obtain a copy of the
* License at http://www.apple.com/publicsource and read it before using
* this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
* License for the specific language governing rights and limitations
* under the License."
*
* @APPLE_LICENSE_HEADER_END@
*/
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
* Copyright (c) 1989, 1993, 1995
* 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 8.14 (Berkeley) 5/21/95
*/
#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>
#ifdef NeXT
#include <sys/malloc.h>
#include <bsd/dev/disk.h>
#else
#include <sys/disklabel.h>
#endif
#include <miscfs/specfs/specdev.h>
#include <vfs/vfs_support.h>
#ifdef NeXT
extern int doclusterread, doclusterwrite;
#endif
struct vnode *speclisth[SPECHSZ];
/* 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, err_create }, /* create */
{ &vop_mknod_desc, err_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_lease_desc, nop_lease }, /* lease */
{ &vop_ioctl_desc, spec_ioctl }, /* ioctl */
{ &vop_select_desc, spec_select }, /* select */
{ &vop_revoke_desc, nop_revoke }, /* revoke */
{ &vop_mmap_desc, err_mmap }, /* mmap */
{ &vop_fsync_desc, spec_fsync }, /* fsync */
{ &vop_seek_desc, err_seek }, /* seek */
{ &vop_remove_desc, err_remove }, /* remove */
{ &vop_link_desc, err_link }, /* link */
{ &vop_rename_desc, err_rename }, /* rename */
{ &vop_mkdir_desc, err_mkdir }, /* mkdir */
{ &vop_rmdir_desc, err_rmdir }, /* rmdir */
{ &vop_symlink_desc, err_symlink }, /* symlink */
{ &vop_readdir_desc, err_readdir }, /* readdir */
{ &vop_readlink_desc, err_readlink }, /* readlink */
{ &vop_abortop_desc, err_abortop }, /* abortop */
{ &vop_inactive_desc, nop_inactive }, /* inactive */
{ &vop_reclaim_desc, nop_reclaim }, /* reclaim */
{ &vop_lock_desc, nop_lock }, /* lock */
{ &vop_unlock_desc, nop_unlock }, /* unlock */
{ &vop_bmap_desc, spec_bmap }, /* bmap */
{ &vop_strategy_desc, spec_strategy }, /* strategy */
{ &vop_print_desc, spec_print }, /* print */
{ &vop_islocked_desc, nop_islocked }, /* islocked */
{ &vop_pathconf_desc, spec_pathconf }, /* pathconf */
{ &vop_advlock_desc, err_advlock }, /* advlock */
{ &vop_blkatoff_desc, err_blkatoff }, /* blkatoff */
{ &vop_valloc_desc, err_valloc }, /* valloc */
{ &vop_vfree_desc, err_vfree }, /* vfree */
{ &vop_truncate_desc, nop_truncate }, /* truncate */
{ &vop_update_desc, nop_update }, /* update */
{ &vop_bwrite_desc, spec_bwrite }, /* bwrite */
#ifdef NeXT
{ &vop_devblocksize_desc, spec_devblocksize }, /* devblocksize */
#endif /* NeXT */
{ &vop_pagein_desc, spec_pagein }, /* Pagein */
{ &vop_pageout_desc, spec_pageout }, /* Pageout */
{ (struct vnodeop_desc*)NULL, (int(*)())NULL }
};
struct vnodeopv_desc spec_vnodeop_opv_desc =
{ &spec_vnodeop_p, spec_vnodeop_entries };
/*
* 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);
}
#ifdef NeXT
void
set_blocksize(struct vnode *vp, dev_t dev)
{
int (*size)();
int rsize;
if ((major(dev) < nblkdev) && (size = bdevsw[major(dev)].d_psize)) {
rsize = (*size)(dev);
if (rsize <= 0) /* did size fail? */
vp->v_specsize = DEV_BSIZE;
else
vp->v_specsize = rsize;
}
else
vp->v_specsize = DEV_BSIZE;
}
#endif /* NeXT */
/*
* Open a special file.
*/
/* ARGSUSED */
spec_open(ap)
struct vop_open_args /* {
struct vnode *a_vp;
int a_mode;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct proc *p = ap->a_p;
struct vnode *bvp, *vp = ap->a_vp;
dev_t bdev, dev = (dev_t)vp->v_rdev;
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);
}
}
if (cdevsw[maj].d_type == D_TTY)
vp->v_flag |= VISTTY;
VOP_UNLOCK(vp, 0, p);
error = (*cdevsw[maj].d_open)(dev, ap->a_mode, S_IFCHR, p);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
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) && bdevsw[maj].d_type == D_DISK)
return (EPERM);
/*
* Do not allow opens of block devices that are
* currently mounted.
*/
if (error = vfs_mountedon(vp))
return (error);
#ifdef NeXT
error = (*bdevsw[maj].d_open)(dev, ap->a_mode, S_IFBLK, p);
if (!error) {
set_blocksize(vp, dev);
}
return(error);
#else
return ((*bdevsw[maj].d_open)(dev, ap->a_mode, S_IFBLK, p));
#endif /* NeXT */
}
return (0);
}
/*
* Vnode op for read
*/
/* ARGSUSED */
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;
#ifdef NeXT
int devBlockSize=0;
int firstpass, seq;
#else
struct partinfo dpart;
#endif /* NeXT */
int n, on, majordev, (*ioctl)();
int error = 0;
dev_t dev;
#if DIAGNOSTIC
if (uio->uio_rw != UIO_READ)
panic("spec_read mode");
if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != current_proc())
panic("spec_read proc");
#endif
if (uio->uio_resid == 0)
return (0);
switch (vp->v_type) {
case VCHR:
VOP_UNLOCK(vp, 0, p);
error = (*cdevsw[major(vp->v_rdev)].d_read)
(vp->v_rdev, uio, ap->a_ioflag);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
return (error);
case VBLK:
if (uio->uio_offset < 0)
return (EINVAL);
#ifdef NeXT
bsize = PAGE_SIZE;
#else
bsize = BLKDEV_IOSIZE;
#endif /* NeXT */
dev = vp->v_rdev;
#ifndef NeXT
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;
#endif /* NeXT */
#ifdef NeXT /*[ */
devBlockSize = vp->v_specsize;
bscale = bsize / devBlockSize;
firstpass = TRUE;
do {
on = uio->uio_offset % bsize;
if (doclusterread && doclusterwrite) {
bn = uio->uio_offset / bsize;
error = cluster_read(vp, (u_quad_t)0x7fffffffffffffff, bn, bsize, NOCRED,
&bp, devBlockSize, firstpass, uio->uio_resid+on, &seq);
} else {
bn = (uio->uio_offset / devBlockSize) &~ (bscale - 1);
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);
}
firstpass = FALSE;
vp->v_lastr = bn;
n = bsize - bp->b_resid;
if ((on > n) || error) {
if (!error)
error = EINVAL;
brelse(bp);
return (error);
}
n = min((unsigned)(n - on), uio->uio_resid);
error = uiomove((char *)bp->b_data + on, n, uio);
if (n + on == bsize)
bp->b_flags |= B_AGE;
brelse(bp);
} while (error == 0 && uio->uio_resid > 0 && n != 0);
#else /*][ */
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);
if (n + on == bsize)
bp->b_flags |= B_AGE;
brelse(bp);
} while (error == 0 && uio->uio_resid > 0 && n != 0);
#endif NeXT /* ] */
return (error);
default:
panic("spec_read type");
}
/* NOTREACHED */
}
/*
* Vnode op for write
*/
/* ARGSUSED */
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;
#ifdef NeXT
register int io_sync;
register int io_size;
register int forcewrite;
int devBlockSize=0;
#else
struct partinfo dpart;
#endif
register int n, on;
int error = 0;
dev_t dev;
#if DIAGNOSTIC
if (uio->uio_rw != UIO_WRITE)
panic("spec_write mode");
if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != current_proc())
panic("spec_write proc");
#endif
switch (vp->v_type) {
case VCHR:
VOP_UNLOCK(vp, 0, p);
error = (*cdevsw[major(vp->v_rdev)].d_write)
(vp->v_rdev, uio, ap->a_ioflag);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
return (error);
case VBLK:
if (uio->uio_resid == 0)
return (0);
if (uio->uio_offset < 0)
return (EINVAL);
#ifdef NeXT
bsize = PAGE_SIZE;
io_sync = (ap->a_ioflag & IO_SYNC);
io_size = uio->uio_resid;
#else
bsize = BLKDEV_IOSIZE;
#endif /* NeXT */
dev = (vp->v_rdev);
#ifndef NeXT
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;
}
#endif /* NeXT */
#ifdef NeXT /* [ */
devBlockSize = vp->v_specsize;
blkmask = (bsize / devBlockSize) - 1;
do {
forcewrite = 0;
if (doclusterread && doclusterwrite)
bn = uio->uio_offset / bsize;
else
bn = (uio->uio_offset / devBlockSize) &~ blkmask;
on = uio->uio_offset % bsize;
n = min((unsigned)(bsize - on), uio->uio_resid);
if (doclusterread && doclusterwrite) {
bp = getblk(vp, bn, bsize, 0, 0);
VOP_BMAP(vp, bn, NULL, &bp->b_blkno, NULL);
if (n != bsize && !(bp->b_flags & (B_DONE|B_DELWRI))) {
if ((on % devBlockSize) || (n % devBlockSize)) {
bp->b_flags |= B_READ;
VOP_STRATEGY(bp);
error = biowait(bp);
} else {
if (on) {
bp->b_blkno += (on / devBlockSize);
on = 0;
}
forcewrite = 1;
bp->b_bcount = n;
bp->b_flags |= B_INVAL;
}
}
} else {
if (n == bsize)
bp = getblk(vp, bn, bsize, 0, 0);
else
error = bread(vp, bn, bsize, NOCRED, &bp);
}
if (error) {
brelse(bp);
return (error);
}
n = min(n, bsize - bp->b_resid);
error = uiomove((char *)bp->b_data + on, n, uio);
if (forcewrite) {
if (uio->uio_resid == 0)
bwrite(bp);
else
bawrite(bp);
} else if (((io_size >= bsize) || ((n + on) == bsize)) && doclusterread && doclusterwrite) {
if (io_sync) {
if (uio->uio_resid < bsize)
bp->b_flags |= (B_CLUST_SYNC | B_CLUST_COMMIT);
else
bp->b_flags |= B_CLUST_SYNC;
error = cluster_write(bp, (u_quad_t)0x7fffffffffffffff, devBlockSize);
} else
cluster_write(bp, (u_quad_t)0x7fffffffffffffff, devBlockSize);
} else {
bp->b_flags |= B_AGE;
if (io_sync)
bwrite(bp);
else {
if ((n + on) == bsize)
bawrite(bp);
else
bdwrite(bp);
}
}
} while (error == 0 && uio->uio_resid > 0 && n != 0);
#else /*][ */
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) {
bp->b_flags |= B_AGE;
bawrite(bp);
} else
bdwrite(bp);
} while (error == 0 && uio->uio_resid > 0 && n != 0);
#endif NeXT /* ] */
return (error);
default:
panic("spec_write type");
}
/* NOTREACHED */
}
/*
* Device ioctl operation.
*/
/* ARGSUSED */
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_type == D_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 */
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;
tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "spec_fsync", 0);
}
#if DIAGNOSTIC
if (vp->v_dirtyblkhd.lh_first) {
vprint("spec_fsync: dirty", vp);
splx(s);
goto loop;
}
#endif
}
splx(s);
return (0);
}
/*
* Just call the device strategy routine
*/
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.
*/
spec_bmap(ap)
struct vop_bmap_args /* {
struct vnode *a_vp;
daddr_t a_bn;
struct vnode **a_vpp;
daddr_t *a_bnp;
int *a_runp;
} */ *ap;
{
if (ap->a_vpp != NULL)
*ap->a_vpp = ap->a_vp;
if (ap->a_bnp != NULL)
#ifdef NeXT
*ap->a_bnp = ap->a_bn * (PAGE_SIZE / ap->a_vp->v_specsize);
#else
*ap->a_bnp = ap->a_bn;
#endif
if (ap->a_runp != NULL)
#ifdef NeXT
*ap->a_runp = (MAXPHYSIO / PAGE_SIZE) - 1;
#else
*ap->a_runp = 0;
#endif
return (0);
}
/*
* Device close routine
*/
/* ARGSUSED */
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.
*/
if (error = vinvalbuf(vp, V_SAVE, ap->a_cred, ap->a_p, 0, 0))
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.
*/
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 POSIX pathconf information applicable to special devices.
*/
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 */
}
int
spec_devblocksize(ap)
struct vop_devblocksize_args /* {
struct vnode *a_vp;
int *a_retval;
} */ *ap;
{
*ap->a_retval = (ap->a_vp->v_specsize);
return (0);
}
/*
* Special device failed operation
*/
spec_ebadf()
{
return (EBADF);
}
/*
* Special device bad operation
*/
spec_badop()
{
panic("spec_badop called");
/* NOTREACHED */
}
/* Pagein */
spec_pagein(ap)
struct vop_pagein_args /* {
struct vnode *a_vp;
struct uio *a_uio;
int a_ioflag;
struct ucred *a_cred;
} */ *ap;
{
/* pass thru to read */
return (VOP_READ(ap->a_vp, ap->a_uio, ap->a_ioflag, ap->a_cred));
}
/* Pageout */
spec_pageout(ap)
struct vop_pageout_args /* {
struct vnode *a_vp;
struct uio *a_uio;
int a_ioflag;
struct ucred *a_cred;
} */ *ap;
{
/* pass thru to write */
return (VOP_WRITE(ap->a_vp, ap->a_uio, ap->a_ioflag, ap->a_cred));
}