536 lines
12 KiB
C
536 lines
12 KiB
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 8.2 (Berkeley) 1/21/94
|
|
* $Id: vfs_vnops.c,v 1.37 1997/09/02 20:06:04 bde Exp $
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/fcntl.h>
|
|
#include <sys/file.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/mount.h>
|
|
#include <sys/namei.h>
|
|
#include <sys/vnode.h>
|
|
#include <sys/filio.h>
|
|
#include <sys/ttycom.h>
|
|
|
|
static int vn_closefile __P((struct file *fp, struct proc *p));
|
|
static int vn_ioctl __P((struct file *fp, int com, caddr_t data,
|
|
struct proc *p));
|
|
static int vn_read __P((struct file *fp, struct uio *uio,
|
|
struct ucred *cred));
|
|
static int vn_poll __P((struct file *fp, int events, struct ucred *cred,
|
|
struct proc *p));
|
|
static int vn_write __P((struct file *fp, struct uio *uio,
|
|
struct ucred *cred));
|
|
|
|
struct fileops vnops =
|
|
{ vn_read, vn_write, vn_ioctl, vn_poll, vn_closefile };
|
|
|
|
/*
|
|
* Common code for vnode open operations.
|
|
* Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
|
|
*/
|
|
int
|
|
vn_open(ndp, fmode, cmode)
|
|
register struct nameidata *ndp;
|
|
int fmode, cmode;
|
|
{
|
|
register struct vnode *vp;
|
|
register struct proc *p = ndp->ni_cnd.cn_proc;
|
|
register struct ucred *cred = p->p_ucred;
|
|
struct vattr vat;
|
|
struct vattr *vap = &vat;
|
|
int error;
|
|
|
|
if (fmode & O_CREAT) {
|
|
ndp->ni_cnd.cn_nameiop = CREATE;
|
|
ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF;
|
|
if ((fmode & O_EXCL) == 0)
|
|
ndp->ni_cnd.cn_flags |= FOLLOW;
|
|
error = namei(ndp);
|
|
if (error)
|
|
return (error);
|
|
if (ndp->ni_vp == NULL) {
|
|
VATTR_NULL(vap);
|
|
vap->va_type = VREG;
|
|
vap->va_mode = cmode;
|
|
if (fmode & O_EXCL)
|
|
vap->va_vaflags |= VA_EXCLUSIVE;
|
|
VOP_LEASE(ndp->ni_dvp, p, cred, LEASE_WRITE);
|
|
if (error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
|
|
&ndp->ni_cnd, vap))
|
|
return (error);
|
|
ASSERT_VOP_UNLOCKED(ndp->ni_dvp, "create");
|
|
ASSERT_VOP_LOCKED(ndp->ni_vp, "create");
|
|
fmode &= ~O_TRUNC;
|
|
vp = ndp->ni_vp;
|
|
} else {
|
|
VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd);
|
|
if (ndp->ni_dvp == ndp->ni_vp)
|
|
vrele(ndp->ni_dvp);
|
|
else
|
|
vput(ndp->ni_dvp);
|
|
ndp->ni_dvp = NULL;
|
|
vp = ndp->ni_vp;
|
|
if (fmode & O_EXCL) {
|
|
error = EEXIST;
|
|
goto bad;
|
|
}
|
|
fmode &= ~O_CREAT;
|
|
}
|
|
} else {
|
|
ndp->ni_cnd.cn_nameiop = LOOKUP;
|
|
ndp->ni_cnd.cn_flags = FOLLOW | LOCKLEAF;
|
|
error = namei(ndp);
|
|
if (error)
|
|
return (error);
|
|
vp = ndp->ni_vp;
|
|
}
|
|
if (vp->v_type == VSOCK) {
|
|
error = EOPNOTSUPP;
|
|
goto bad;
|
|
}
|
|
if ((fmode & O_CREAT) == 0) {
|
|
if (fmode & FREAD) {
|
|
error = VOP_ACCESS(vp, VREAD, cred, p);
|
|
if (error)
|
|
goto bad;
|
|
}
|
|
if (fmode & (FWRITE | O_TRUNC)) {
|
|
if (vp->v_type == VDIR) {
|
|
error = EISDIR;
|
|
goto bad;
|
|
}
|
|
error = vn_writechk(vp);
|
|
if (error)
|
|
goto bad;
|
|
error = VOP_ACCESS(vp, VWRITE, cred, p);
|
|
if (error)
|
|
goto bad;
|
|
}
|
|
}
|
|
if (fmode & O_TRUNC) {
|
|
VOP_UNLOCK(vp, 0, p); /* XXX */
|
|
VOP_LEASE(vp, p, cred, LEASE_WRITE);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); /* XXX */
|
|
VATTR_NULL(vap);
|
|
vap->va_size = 0;
|
|
error = VOP_SETATTR(vp, vap, cred, p);
|
|
if (error)
|
|
goto bad;
|
|
}
|
|
error = VOP_OPEN(vp, fmode, cred, p);
|
|
if (error)
|
|
goto bad;
|
|
/*
|
|
* Make sure that a VM object is created for VMIO support.
|
|
*/
|
|
if (vp->v_type == VREG) {
|
|
if ((error = vfs_object_create(vp, p, cred, 1)) != 0)
|
|
goto bad;
|
|
}
|
|
|
|
if (fmode & FWRITE)
|
|
vp->v_writecount++;
|
|
return (0);
|
|
bad:
|
|
vput(vp);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Check for write permissions on the specified vnode.
|
|
* Prototype text segments cannot be written.
|
|
*/
|
|
int
|
|
vn_writechk(vp)
|
|
register struct vnode *vp;
|
|
{
|
|
|
|
/*
|
|
* If there's shared text associated with
|
|
* the vnode, try to free it up once. If
|
|
* we fail, we can't allow writing.
|
|
*/
|
|
if (vp->v_flag & VTEXT)
|
|
return (ETXTBSY);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Vnode close call
|
|
*/
|
|
int
|
|
vn_close(vp, flags, cred, p)
|
|
register struct vnode *vp;
|
|
int flags;
|
|
struct ucred *cred;
|
|
struct proc *p;
|
|
{
|
|
int error;
|
|
|
|
if (flags & FWRITE)
|
|
vp->v_writecount--;
|
|
error = VOP_CLOSE(vp, flags, cred, p);
|
|
vrele(vp);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Package up an I/O request on a vnode into a uio and do it.
|
|
*/
|
|
int
|
|
vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, cred, aresid, p)
|
|
enum uio_rw rw;
|
|
struct vnode *vp;
|
|
caddr_t base;
|
|
int len;
|
|
off_t offset;
|
|
enum uio_seg segflg;
|
|
int ioflg;
|
|
struct ucred *cred;
|
|
int *aresid;
|
|
struct proc *p;
|
|
{
|
|
struct uio auio;
|
|
struct iovec aiov;
|
|
int error;
|
|
|
|
if ((ioflg & IO_NODELOCKED) == 0)
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
|
|
auio.uio_iov = &aiov;
|
|
auio.uio_iovcnt = 1;
|
|
aiov.iov_base = base;
|
|
aiov.iov_len = len;
|
|
auio.uio_resid = len;
|
|
auio.uio_offset = offset;
|
|
auio.uio_segflg = segflg;
|
|
auio.uio_rw = rw;
|
|
auio.uio_procp = p;
|
|
if (rw == UIO_READ) {
|
|
error = VOP_READ(vp, &auio, ioflg, cred);
|
|
} else {
|
|
error = VOP_WRITE(vp, &auio, ioflg, cred);
|
|
}
|
|
if (aresid)
|
|
*aresid = auio.uio_resid;
|
|
else
|
|
if (auio.uio_resid && error == 0)
|
|
error = EIO;
|
|
if ((ioflg & IO_NODELOCKED) == 0)
|
|
VOP_UNLOCK(vp, 0, p);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode read routine.
|
|
*/
|
|
static int
|
|
vn_read(fp, uio, cred)
|
|
struct file *fp;
|
|
struct uio *uio;
|
|
struct ucred *cred;
|
|
{
|
|
struct vnode *vp = (struct vnode *)fp->f_data;
|
|
struct proc *p = uio->uio_procp;
|
|
int count, error;
|
|
int flag, seq;
|
|
|
|
VOP_LEASE(vp, p, cred, LEASE_READ);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
|
|
uio->uio_offset = fp->f_offset;
|
|
count = uio->uio_resid;
|
|
flag = 0;
|
|
if (fp->f_flag & FNONBLOCK)
|
|
flag |= IO_NDELAY;
|
|
|
|
/*
|
|
* Sequential read heuristic.
|
|
* If we have been doing sequential input,
|
|
* a rewind operation doesn't turn off
|
|
* sequential input mode.
|
|
*/
|
|
if (((fp->f_offset == 0) && (fp->f_seqcount > 0)) ||
|
|
(fp->f_offset == fp->f_nextread)) {
|
|
int tmpseq = fp->f_seqcount;
|
|
/*
|
|
* XXX we assume that the filesystem block size is
|
|
* the default. Not true, but still gives us a pretty
|
|
* good indicator of how sequential the read operations
|
|
* are.
|
|
*/
|
|
tmpseq += ((count + BKVASIZE - 1) / BKVASIZE);
|
|
if (tmpseq >= CHAR_MAX)
|
|
tmpseq = CHAR_MAX;
|
|
fp->f_seqcount = tmpseq;
|
|
flag |= (fp->f_seqcount << 16);
|
|
} else {
|
|
if (fp->f_seqcount > 1)
|
|
fp->f_seqcount = 1;
|
|
else
|
|
fp->f_seqcount = 0;
|
|
}
|
|
|
|
error = VOP_READ(vp, uio, flag, cred);
|
|
fp->f_offset += count - uio->uio_resid;
|
|
fp->f_nextread = fp->f_offset;
|
|
VOP_UNLOCK(vp, 0, p);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode write routine.
|
|
*/
|
|
static int
|
|
vn_write(fp, uio, cred)
|
|
struct file *fp;
|
|
struct uio *uio;
|
|
struct ucred *cred;
|
|
{
|
|
struct vnode *vp = (struct vnode *)fp->f_data;
|
|
struct proc *p = uio->uio_procp;
|
|
int count, error, ioflag = IO_UNIT;
|
|
|
|
if (vp->v_type == VREG && (fp->f_flag & O_APPEND))
|
|
ioflag |= IO_APPEND;
|
|
if (fp->f_flag & FNONBLOCK)
|
|
ioflag |= IO_NDELAY;
|
|
if ((fp->f_flag & O_FSYNC) ||
|
|
(vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
|
|
ioflag |= IO_SYNC;
|
|
VOP_LEASE(vp, p, cred, LEASE_WRITE);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
|
|
uio->uio_offset = fp->f_offset;
|
|
count = uio->uio_resid;
|
|
error = VOP_WRITE(vp, uio, ioflag, cred);
|
|
if (ioflag & IO_APPEND)
|
|
fp->f_offset = uio->uio_offset;
|
|
else
|
|
fp->f_offset += count - uio->uio_resid;
|
|
VOP_UNLOCK(vp, 0, p);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* File table vnode stat routine.
|
|
*/
|
|
int
|
|
vn_stat(vp, sb, p)
|
|
struct vnode *vp;
|
|
register struct stat *sb;
|
|
struct proc *p;
|
|
{
|
|
struct vattr vattr;
|
|
register struct vattr *vap;
|
|
int error;
|
|
u_short mode;
|
|
|
|
vap = &vattr;
|
|
error = VOP_GETATTR(vp, vap, p->p_ucred, p);
|
|
if (error)
|
|
return (error);
|
|
/*
|
|
* Copy from vattr table
|
|
*/
|
|
sb->st_dev = vap->va_fsid;
|
|
sb->st_ino = vap->va_fileid;
|
|
mode = vap->va_mode;
|
|
switch (vp->v_type) {
|
|
case VREG:
|
|
mode |= S_IFREG;
|
|
break;
|
|
case VDIR:
|
|
mode |= S_IFDIR;
|
|
break;
|
|
case VBLK:
|
|
mode |= S_IFBLK;
|
|
break;
|
|
case VCHR:
|
|
mode |= S_IFCHR;
|
|
break;
|
|
case VLNK:
|
|
mode |= S_IFLNK;
|
|
break;
|
|
case VSOCK:
|
|
mode |= S_IFSOCK;
|
|
break;
|
|
case VFIFO:
|
|
mode |= S_IFIFO;
|
|
break;
|
|
default:
|
|
return (EBADF);
|
|
};
|
|
sb->st_mode = mode;
|
|
sb->st_nlink = vap->va_nlink;
|
|
sb->st_uid = vap->va_uid;
|
|
sb->st_gid = vap->va_gid;
|
|
sb->st_rdev = vap->va_rdev;
|
|
sb->st_size = vap->va_size;
|
|
sb->st_atimespec = vap->va_atime;
|
|
sb->st_mtimespec = vap->va_mtime;
|
|
sb->st_ctimespec = vap->va_ctime;
|
|
sb->st_blksize = vap->va_blocksize;
|
|
sb->st_flags = vap->va_flags;
|
|
if (p->p_ucred->cr_uid != 0)
|
|
sb->st_gen = 0;
|
|
else
|
|
sb->st_gen = vap->va_gen;
|
|
|
|
#if (S_BLKSIZE == 512)
|
|
/* Optimize this case */
|
|
sb->st_blocks = vap->va_bytes >> 9;
|
|
#else
|
|
sb->st_blocks = vap->va_bytes / S_BLKSIZE;
|
|
#endif
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* File table vnode ioctl routine.
|
|
*/
|
|
static int
|
|
vn_ioctl(fp, com, data, p)
|
|
struct file *fp;
|
|
int com;
|
|
caddr_t data;
|
|
struct proc *p;
|
|
{
|
|
register struct vnode *vp = ((struct vnode *)fp->f_data);
|
|
struct vattr vattr;
|
|
int error;
|
|
|
|
switch (vp->v_type) {
|
|
|
|
case VREG:
|
|
case VDIR:
|
|
if (com == FIONREAD) {
|
|
error = VOP_GETATTR(vp, &vattr, p->p_ucred, p);
|
|
if (error)
|
|
return (error);
|
|
*(int *)data = vattr.va_size - fp->f_offset;
|
|
return (0);
|
|
}
|
|
if (com == FIONBIO || com == FIOASYNC) /* XXX */
|
|
return (0); /* XXX */
|
|
/* fall into ... */
|
|
|
|
default:
|
|
return (ENOTTY);
|
|
|
|
case VFIFO:
|
|
case VCHR:
|
|
case VBLK:
|
|
error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p);
|
|
if (error == 0 && com == TIOCSCTTY) {
|
|
|
|
/* Do nothing if reassigning same control tty */
|
|
if (p->p_session->s_ttyvp == vp)
|
|
return (0);
|
|
|
|
/* Get rid of reference to old control tty */
|
|
if (p->p_session->s_ttyvp)
|
|
vrele(p->p_session->s_ttyvp);
|
|
|
|
p->p_session->s_ttyvp = vp;
|
|
VREF(vp);
|
|
}
|
|
return (error);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* File table vnode poll routine.
|
|
*/
|
|
static int
|
|
vn_poll(fp, events, cred, p)
|
|
struct file *fp;
|
|
int events;
|
|
struct ucred *cred;
|
|
struct proc *p;
|
|
{
|
|
|
|
return (VOP_POLL(((struct vnode *)fp->f_data), events, cred, p));
|
|
}
|
|
|
|
/*
|
|
* File table vnode close routine.
|
|
*/
|
|
static int
|
|
vn_closefile(fp, p)
|
|
struct file *fp;
|
|
struct proc *p;
|
|
{
|
|
|
|
return (vn_close(((struct vnode *)fp->f_data), fp->f_flag,
|
|
fp->f_cred, p));
|
|
}
|
|
|
|
/*
|
|
* Check that the vnode is still valid, and if so
|
|
* acquire requested lock.
|
|
*/
|
|
int
|
|
vn_lock(vp, flags, p)
|
|
struct vnode *vp;
|
|
int flags;
|
|
struct proc *p;
|
|
{
|
|
int error;
|
|
|
|
do {
|
|
if ((flags & LK_INTERLOCK) == 0) {
|
|
simple_lock(&vp->v_interlock);
|
|
}
|
|
if (vp->v_flag & VXLOCK) {
|
|
vp->v_flag |= VXWANT;
|
|
simple_unlock(&vp->v_interlock);
|
|
tsleep((caddr_t)vp, PINOD, "vn_lock", 0);
|
|
error = ENOENT;
|
|
} else {
|
|
error = VOP_LOCK(vp, flags | LK_INTERLOCK, p);
|
|
if (error == 0)
|
|
return (error);
|
|
}
|
|
flags &= ~LK_INTERLOCK;
|
|
} while (flags & LK_RETRY);
|
|
return (error);
|
|
}
|