2.11BSD/sys/sys/vfs_vnops.c
/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* 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.
*
* @(#)vfs_vnops.c 8.14.4 (2.11BSD) 1999/9/13
*/
#include <sys/param.h>
#include <sys/file.h>
#include <sys/user.h>
#include <sys/namei.h>
#include <sys/inode.h>
#include <sys/stat.h>
/*
* 2.11BSD does not have "vnodes", having instead only old fashioned "inodes".
* The routine names (i.e. vn_open) were retained since the functions them-
* selves were ported over with minimal change. Retaining the 4.4 function
* names also makes it easier to follow the logic flow when reading the 4.4
* sources. Also, changing the names from vn_* to in_* could have caused
* confusion with the networking routines since 'in_' and 'ip_' are frequently
* used in the networking code.
*
* The tab spacing has been altered to be (to me) more readable.
*/
/*
* Common code for vnode open operations.
* Check permissions, and call the VOP_OPEN (openi for 2.11) or VOP_CREATE
* (maknode) routine.
*/
vn_open(ndp, fmode, cmode)
register struct nameidata *ndp;
int fmode, cmode;
{
register struct inode *ip;
register int error;
if (fmode & O_CREAT)
{
if ((fmode & O_EXCL) == 0)
ndp->ni_nameiop |= (CREATE|FOLLOW);
else
ndp->ni_nameiop= CREATE;
ip = namei(ndp);
if (ip == NULL)
{
if (u.u_error)
goto retuerr;
ip = maknode(cmode, ndp);
if (ip == NULL)
goto retuerr;
fmode &= ~O_TRUNC;
}
else
{
if (fmode & O_EXCL)
{
error = EEXIST;
goto bad;
}
fmode &= ~O_CREAT;
}
}
else
{
ndp->ni_nameiop = LOOKUP | FOLLOW;
ip = namei(ndp);
if (ip == NULL)
goto retuerr;
}
if ((ip->i_mode & IFMT) == IFSOCK)
{
error = EOPNOTSUPP;
goto bad;
}
if ((ip->i_flags & APPEND) && (fmode&(FWRITE|O_APPEND)) == FWRITE)
{
error = EPERM;
goto bad;
}
if ((fmode & O_CREAT) == 0)
{
if (fmode & FREAD)
{
if (access(ip, IREAD))
{
error = u.u_error; /* XXX */
goto bad;
}
}
if (fmode & (FWRITE | O_TRUNC))
{
if ((ip->i_mode & IFMT) == IFDIR)
{
error = EISDIR;
goto bad;
}
if (access(ip, IWRITE))
{
error = u.u_error;
goto bad;
}
}
}
if (fmode & O_TRUNC)
itrunc(ip, (off_t)0, fmode & O_FSYNC ? IO_SYNC : 0);
/*
* 4.4 returns the vnode locked from vn_open which means that each caller
* has to go and unlock it.
*
* 2.11 returns the inode unlocked (for now).
*/
iunlock(ip); /* because namei returns a locked inode */
if (setjmp(&u.u_qsave))
{
error = EINTR; /* opens are not restarted after signals */
goto lbad;
}
if (error = openi(ip, fmode))
goto lbad;
return(0);
/*
* Gratuitous lock but it does (correctly) implement the earlier behaviour of
* copen (it also avoids a panic in iput).
*/
lbad:
ilock(ip);
bad:
/*
* Do NOT do an 'ilock' here - this tag is to be used only when the inode is
* locked (i.e. from namei).
*/
iput(ip);
return(error);
retuerr:
return(u.u_error); /* XXX - Bletch */
}
/*
* Inode close call. Pipes and sockets do NOT enter here. This routine is
* used by the kernel to close files it opened for itself (see kern_acct.c
* for a good example of this). The kernel does not create sockets or pipes
* on its own behalf.
*
* The difference between this routine and vn_closefile below is that vn_close
* takes an "inode *" as a first argument and is passed the flags by the caller
* while vn_closefile (called from the closef routine for DTYPE_INODE inodes)
* takes a "file *" and extracts the flags from the file structure.
*/
vn_close(ip, flags)
register struct inode *ip;
int flags;
{
register int error;
error = closei(ip, flags);
irele(ip); /* assumes inode is unlocked */
return(error);
}
/*
* File table inode close routine. This is called from 'closef()' via the
* "Fops" table (the 'inodeops' entry).
*
* NOTE: pipes are a special case of inode and have their own 'pipe_close'
* entry in the 'pipeops' table. See sys_pipe.c for pipe_close().
*
* In 4.4BSD this routine called vn_close() but since 2.11 does not do the
* writecheck counting we can skip the overhead of nesting another level down
* and call closei() and irele() ourself.
*/
vn_closefile(fp)
register struct file *fp;
{
register struct inode *ip = (struct inode *)fp->f_data;
/*
* Need to clear the inode pointer in the file structure so that the
* inode is not seen during the scan for aliases of character or block
* devices in closei().
*/
fp->f_data = (caddr_t)0; /* XXX */
irele(ip);
return(closei(ip, fp->f_flag));
}