/
ufs_vnops.c
1993 lines (1822 loc) · 46.7 KB
/
ufs_vnops.c
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/* $OpenBSD: ufs_vnops.c,v 1.146 2019/08/05 08:35:59 anton Exp $ */
/* $NetBSD: ufs_vnops.c,v 1.18 1996/05/11 18:28:04 mycroft Exp $ */
/*
* 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. 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.
*
* @(#)ufs_vnops.c 8.14 (Berkeley) 10/26/94
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/resourcevar.h>
#include <sys/kernel.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
#include <sys/pool.h>
#include <sys/dirent.h>
#include <sys/lockf.h>
#include <sys/event.h>
#include <sys/poll.h>
#include <sys/specdev.h>
#include <sys/unistd.h>
#include <miscfs/fifofs/fifo.h>
#include <ufs/ufs/quota.h>
#include <ufs/ufs/inode.h>
#include <ufs/ufs/dir.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/ufs_extern.h>
#ifdef UFS_DIRHASH
#include <ufs/ufs/dirhash.h>
#endif
#include <ufs/ext2fs/ext2fs_extern.h>
#include <uvm/uvm_extern.h>
int ufs_chmod(struct vnode *, int, struct ucred *, struct proc *);
int ufs_chown(struct vnode *, uid_t, gid_t, struct ucred *, struct proc *);
int filt_ufsread(struct knote *, long);
int filt_ufswrite(struct knote *, long);
int filt_ufsvnode(struct knote *, long);
void filt_ufsdetach(struct knote *);
/*
* A virgin directory (no blushing please).
*/
static struct dirtemplate mastertemplate = {
0, 12, DT_DIR, 1, ".",
0, DIRBLKSIZ - 12, DT_DIR, 2, ".."
};
static struct odirtemplate omastertemplate = {
0, 12, 1, ".",
0, DIRBLKSIZ - 12, 2, ".."
};
/*
* Update the times in the inode
*/
void
ufs_itimes(struct vnode *vp)
{
struct inode *ip;
struct timespec ts;
ip = VTOI(vp);
if ((ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_UPDATE)) == 0)
return;
if (vp->v_mount->mnt_flag & MNT_RDONLY)
goto out;
#ifdef EXT2FS
if (IS_EXT2_VNODE(ip->i_vnode)) {
EXT2FS_ITIMES(ip);
goto out;
}
#endif
if ((vp->v_type == VBLK || vp->v_type == VCHR) && !DOINGSOFTDEP(vp))
ip->i_flag |= IN_LAZYMOD;
else
ip->i_flag |= IN_MODIFIED;
getnanotime(&ts);
if (ip->i_flag & IN_ACCESS) {
DIP_ASSIGN(ip, atime, ts.tv_sec);
DIP_ASSIGN(ip, atimensec, ts.tv_nsec);
}
if (ip->i_flag & IN_UPDATE) {
DIP_ASSIGN(ip, mtime, ts.tv_sec);
DIP_ASSIGN(ip, mtimensec, ts.tv_nsec);
}
if (ip->i_flag & IN_CHANGE) {
DIP_ASSIGN(ip, ctime, ts.tv_sec);
DIP_ASSIGN(ip, ctimensec, ts.tv_nsec);
ip->i_modrev++;
}
out:
ip->i_flag &= ~(IN_ACCESS | IN_CHANGE | IN_UPDATE);
}
/*
* Create a regular file
*/
int
ufs_create(void *v)
{
struct vop_create_args *ap = v;
int error;
error =
ufs_makeinode(MAKEIMODE(ap->a_vap->va_type, ap->a_vap->va_mode),
ap->a_dvp, ap->a_vpp, ap->a_cnp);
if (error == 0)
VN_KNOTE(ap->a_dvp, NOTE_WRITE);
return (error);
}
/*
* Mknod vnode call
*/
int
ufs_mknod(void *v)
{
struct vop_mknod_args *ap = v;
struct vattr *vap = ap->a_vap;
struct vnode **vpp = ap->a_vpp;
struct inode *ip;
int error;
if ((error =
ufs_makeinode(MAKEIMODE(vap->va_type, vap->va_mode),
ap->a_dvp, vpp, ap->a_cnp)) != 0)
return (error);
VN_KNOTE(ap->a_dvp, NOTE_WRITE);
ip = VTOI(*vpp);
ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
if (vap->va_rdev != VNOVAL) {
/*
* Want to be able to use this to make badblock
* inodes, so don't truncate the dev number.
*/
DIP_ASSIGN(ip, rdev, vap->va_rdev);
}
/*
* Remove inode so that it will be reloaded by VFS_VGET and
* checked to see if it is an alias of an existing entry in
* the inode cache.
*/
vput(*vpp);
(*vpp)->v_type = VNON;
vgone(*vpp);
*vpp = NULL;
return (0);
}
/*
* Open called.
*
* Nothing to do.
*/
int
ufs_open(void *v)
{
struct vop_open_args *ap = v;
struct inode *ip = VTOI(ap->a_vp);
/*
* Files marked append-only must be opened for appending.
*/
if ((DIP(ip, flags) & APPEND) &&
(ap->a_mode & (FWRITE | O_APPEND)) == FWRITE)
return (EPERM);
if (ap->a_mode & O_TRUNC)
ip->i_flag |= IN_CHANGE | IN_UPDATE;
return (0);
}
/*
* Close called.
*
* Update the times on the inode.
*/
int
ufs_close(void *v)
{
struct vop_close_args *ap = v;
struct vnode *vp = ap->a_vp;
if (vp->v_usecount > 1)
ufs_itimes(vp);
return (0);
}
int
ufs_access(void *v)
{
struct vop_access_args *ap = v;
struct vnode *vp = ap->a_vp;
struct inode *ip = VTOI(vp);
mode_t mode = ap->a_mode;
/*
* Disallow write attempts on read-only file systems;
* unless the file is a socket, fifo, or a block or
* character device resident on the file system.
*/
if (mode & VWRITE) {
switch (vp->v_type) {
int error;
case VDIR:
case VLNK:
case VREG:
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if ((error = getinoquota(ip)) != 0)
return (error);
break;
case VBAD:
case VBLK:
case VCHR:
case VSOCK:
case VFIFO:
case VNON:
break;
}
}
/* If immutable bit set, nobody gets to write it. */
if ((mode & VWRITE) && (DIP(ip, flags) & IMMUTABLE))
return (EPERM);
if (vnoperm(vp)) {
/* For VEXEC, at least one of the execute bits must be set. */
if ((mode & VEXEC) && vp->v_type != VDIR &&
(DIP(ip, mode) & (S_IXUSR|S_IXGRP|S_IXOTH)) == 0)
return EACCES;
return 0;
}
return (vaccess(vp->v_type, DIP(ip, mode), DIP(ip, uid), DIP(ip, gid),
mode, ap->a_cred));
}
int
ufs_getattr(void *v)
{
struct vop_getattr_args *ap = v;
struct vnode *vp = ap->a_vp;
struct inode *ip = VTOI(vp);
struct vattr *vap = ap->a_vap;
ufs_itimes(vp);
/*
* Copy from inode table
*/
vap->va_fsid = ip->i_dev;
vap->va_fileid = ip->i_number;
vap->va_mode = DIP(ip, mode) & ~IFMT;
vap->va_nlink = ip->i_effnlink;
vap->va_uid = DIP(ip, uid);
vap->va_gid = DIP(ip, gid);
vap->va_rdev = (dev_t) DIP(ip, rdev);
vap->va_size = DIP(ip, size);
vap->va_atime.tv_sec = DIP(ip, atime);
vap->va_atime.tv_nsec = DIP(ip, atimensec);
vap->va_mtime.tv_sec = DIP(ip, mtime);
vap->va_mtime.tv_nsec = DIP(ip, mtimensec);
vap->va_ctime.tv_sec = DIP(ip, ctime);
vap->va_ctime.tv_nsec = DIP(ip, ctimensec);
vap->va_flags = DIP(ip, flags);
vap->va_gen = DIP(ip, gen);
/* this doesn't belong here */
if (vp->v_type == VBLK)
vap->va_blocksize = BLKDEV_IOSIZE;
else if (vp->v_type == VCHR)
vap->va_blocksize = MAXBSIZE;
else
vap->va_blocksize = vp->v_mount->mnt_stat.f_iosize;
vap->va_bytes = dbtob((u_quad_t) DIP(ip, blocks));
vap->va_type = vp->v_type;
vap->va_filerev = ip->i_modrev;
return (0);
}
/*
* Set attribute vnode op. called from several syscalls
*/
int
ufs_setattr(void *v)
{
struct vop_setattr_args *ap = v;
struct vattr *vap = ap->a_vap;
struct vnode *vp = ap->a_vp;
struct inode *ip = VTOI(vp);
struct ucred *cred = ap->a_cred;
struct proc *p = ap->a_p;
int error;
long hint = NOTE_ATTRIB;
u_quad_t oldsize;
/*
* Check for unsettable attributes.
*/
if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) ||
(vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) ||
(vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) ||
((int)vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) {
return (EINVAL);
}
if (vap->va_flags != VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if (cred->cr_uid != DIP(ip, uid) &&
!vnoperm(vp) &&
(error = suser_ucred(cred)))
return (error);
if (cred->cr_uid == 0 || vnoperm(vp)) {
if ((DIP(ip, flags) & (SF_IMMUTABLE | SF_APPEND)) &&
securelevel > 0)
return (EPERM);
DIP_ASSIGN(ip, flags, vap->va_flags);
} else {
if (DIP(ip, flags) & (SF_IMMUTABLE | SF_APPEND) ||
(vap->va_flags & UF_SETTABLE) != vap->va_flags)
return (EPERM);
DIP_AND(ip, flags, SF_SETTABLE);
DIP_OR(ip, flags, vap->va_flags & UF_SETTABLE);
}
ip->i_flag |= IN_CHANGE;
if (vap->va_flags & (IMMUTABLE | APPEND))
return (0);
}
if (DIP(ip, flags) & (IMMUTABLE | APPEND))
return (EPERM);
/*
* Go through the fields and update if not VNOVAL.
*/
if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
error = ufs_chown(vp, vap->va_uid, vap->va_gid, cred, p);
if (error)
return (error);
}
if (vap->va_size != VNOVAL) {
oldsize = DIP(ip, size);
/*
* Disallow write attempts on read-only file systems;
* unless the file is a socket, fifo, or a block or
* character device resident on the file system.
*/
switch (vp->v_type) {
case VDIR:
return (EISDIR);
case VLNK:
case VREG:
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
break;
default:
break;
}
if ((error = UFS_TRUNCATE(ip, vap->va_size, 0, cred)) != 0)
return (error);
if (vap->va_size < oldsize)
hint |= NOTE_TRUNCATE;
}
if ((vap->va_vaflags & VA_UTIMES_CHANGE) ||
vap->va_atime.tv_nsec != VNOVAL ||
vap->va_mtime.tv_nsec != VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if (cred->cr_uid != DIP(ip, uid) &&
!vnoperm(vp) &&
(error = suser_ucred(cred)) &&
((vap->va_vaflags & VA_UTIMES_NULL) == 0 ||
(error = VOP_ACCESS(vp, VWRITE, cred, p))))
return (error);
if (vap->va_mtime.tv_nsec != VNOVAL)
ip->i_flag |= IN_CHANGE | IN_UPDATE;
else if (vap->va_vaflags & VA_UTIMES_CHANGE)
ip->i_flag |= IN_CHANGE;
if (vap->va_atime.tv_nsec != VNOVAL) {
if (!(vp->v_mount->mnt_flag & MNT_NOATIME) ||
(ip->i_flag & (IN_CHANGE | IN_UPDATE)))
ip->i_flag |= IN_ACCESS;
}
ufs_itimes(vp);
if (vap->va_mtime.tv_nsec != VNOVAL) {
DIP_ASSIGN(ip, mtime, vap->va_mtime.tv_sec);
DIP_ASSIGN(ip, mtimensec, vap->va_mtime.tv_nsec);
}
if (vap->va_atime.tv_nsec != VNOVAL) {
DIP_ASSIGN(ip, atime, vap->va_atime.tv_sec);
DIP_ASSIGN(ip, atimensec, vap->va_atime.tv_nsec);
}
error = UFS_UPDATE(ip, 0);
if (error)
return (error);
}
error = 0;
if (vap->va_mode != (mode_t)VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
error = ufs_chmod(vp, (int)vap->va_mode, cred, p);
}
VN_KNOTE(vp, hint);
return (error);
}
/*
* Change the mode on a file.
* Inode must be locked before calling.
*/
int
ufs_chmod(struct vnode *vp, int mode, struct ucred *cred, struct proc *p)
{
struct inode *ip = VTOI(vp);
int error;
if (cred->cr_uid != DIP(ip, uid) &&
!vnoperm(vp) &&
(error = suser_ucred(cred)))
return (error);
if (cred->cr_uid && !vnoperm(vp)) {
if (vp->v_type != VDIR && (mode & S_ISTXT))
return (EFTYPE);
if (!groupmember(DIP(ip, gid), cred) && (mode & ISGID))
return (EPERM);
}
DIP_AND(ip, mode, ~ALLPERMS);
DIP_OR(ip, mode, mode & ALLPERMS);
ip->i_flag |= IN_CHANGE;
if ((vp->v_flag & VTEXT) && (DIP(ip, mode) & S_ISTXT) == 0)
(void) uvm_vnp_uncache(vp);
return (0);
}
/*
* Perform chown operation on inode ip;
* inode must be locked prior to call.
*/
int
ufs_chown(struct vnode *vp, uid_t uid, gid_t gid, struct ucred *cred,
struct proc *p)
{
struct inode *ip = VTOI(vp);
uid_t ouid;
gid_t ogid;
int error = 0;
daddr_t change;
enum ufs_quota_flags quota_flags = 0;
if (uid == (uid_t)VNOVAL)
uid = DIP(ip, uid);
if (gid == (gid_t)VNOVAL)
gid = DIP(ip, gid);
/*
* If we don't own the file, are trying to change the owner
* of the file, or are not a member of the target group,
* the caller must be superuser or the call fails.
*/
if ((cred->cr_uid != DIP(ip, uid) || uid != DIP(ip, uid) ||
(gid != DIP(ip, gid) && !groupmember(gid, cred))) &&
!vnoperm(vp) &&
(error = suser_ucred(cred)))
return (error);
ogid = DIP(ip, gid);
ouid = DIP(ip, uid);
change = DIP(ip, blocks);
if (ouid == uid)
quota_flags |= UFS_QUOTA_NOUID;
if (ogid == gid)
quota_flags |= UFS_QUOTA_NOGID;
if ((error = getinoquota(ip)) != 0)
return (error);
(void) ufs_quota_free_blocks2(ip, change, cred, quota_flags);
(void) ufs_quota_free_inode2(ip, cred, quota_flags);
(void) ufs_quota_delete(ip);
DIP_ASSIGN(ip, gid, gid);
DIP_ASSIGN(ip, uid, uid);
if ((error = getinoquota(ip)) != 0)
goto error;
if ((error = ufs_quota_alloc_blocks2(ip, change, cred,
quota_flags)) != 0)
goto error;
if ((error = ufs_quota_alloc_inode2(ip, cred ,
quota_flags)) != 0) {
(void)ufs_quota_free_blocks2(ip, change, cred,
quota_flags);
goto error;
}
if (getinoquota(ip))
panic("chown: lost quota");
if (ouid != uid || ogid != gid)
ip->i_flag |= IN_CHANGE;
if (!vnoperm(vp)) {
if (ouid != uid && cred->cr_uid != 0)
DIP_AND(ip, mode, ~ISUID);
if (ogid != gid && cred->cr_uid != 0)
DIP_AND(ip, mode, ~ISGID);
}
return (0);
error:
(void) ufs_quota_delete(ip);
DIP_ASSIGN(ip, gid, ogid);
DIP_ASSIGN(ip, uid, ouid);
if (getinoquota(ip) == 0) {
(void) ufs_quota_alloc_blocks2(ip, change, cred,
quota_flags | UFS_QUOTA_FORCE);
(void) ufs_quota_alloc_inode2(ip, cred,
quota_flags | UFS_QUOTA_FORCE);
(void) getinoquota(ip);
}
return (error);
}
/* ARGSUSED */
int
ufs_ioctl(void *v)
{
#if 0
struct vop_ioctl_args *ap = v;
#endif
return (ENOTTY);
}
int
ufs_poll(void *v)
{
struct vop_poll_args *ap = v;
/*
* We should really check to see if I/O is possible.
*/
return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
}
int
ufs_remove(void *v)
{
struct vop_remove_args *ap = v;
struct inode *ip;
struct vnode *vp = ap->a_vp;
struct vnode *dvp = ap->a_dvp;
int error;
ip = VTOI(vp);
if (vp->v_type == VDIR || (DIP(ip, flags) & (IMMUTABLE | APPEND)) ||
(DIP(VTOI(dvp), flags) & APPEND)) {
error = EPERM;
goto out;
}
error = ufs_dirremove(dvp, ip, ap->a_cnp->cn_flags, 0);
VN_KNOTE(vp, NOTE_DELETE);
VN_KNOTE(dvp, NOTE_WRITE);
out:
if (dvp == vp)
vrele(vp);
else
vput(vp);
vput(dvp);
return (error);
}
/*
* link vnode call
*/
int
ufs_link(void *v)
{
struct vop_link_args *ap = v;
struct vnode *dvp = ap->a_dvp;
struct vnode *vp = ap->a_vp;
struct componentname *cnp = ap->a_cnp;
struct inode *ip;
struct direct newdir;
int error;
#ifdef DIAGNOSTIC
if ((cnp->cn_flags & HASBUF) == 0)
panic("ufs_link: no name");
#endif
if (vp->v_type == VDIR) {
VOP_ABORTOP(dvp, cnp);
error = EPERM;
goto out2;
}
if (dvp->v_mount != vp->v_mount) {
VOP_ABORTOP(dvp, cnp);
error = EXDEV;
goto out2;
}
if (dvp != vp && (error = vn_lock(vp, LK_EXCLUSIVE))) {
VOP_ABORTOP(dvp, cnp);
goto out2;
}
ip = VTOI(vp);
if ((nlink_t) DIP(ip, nlink) >= LINK_MAX) {
VOP_ABORTOP(dvp, cnp);
error = EMLINK;
goto out1;
}
if (DIP(ip, flags) & (IMMUTABLE | APPEND)) {
VOP_ABORTOP(dvp, cnp);
error = EPERM;
goto out1;
}
ip->i_effnlink++;
DIP_ADD(ip, nlink, 1);
ip->i_flag |= IN_CHANGE;
if (DOINGSOFTDEP(vp))
softdep_change_linkcnt(ip, 0);
if ((error = UFS_UPDATE(ip, !DOINGSOFTDEP(vp))) == 0) {
ufs_makedirentry(ip, cnp, &newdir);
error = ufs_direnter(dvp, vp, &newdir, cnp, NULL);
}
if (error) {
ip->i_effnlink--;
DIP_ADD(ip, nlink, -1);
ip->i_flag |= IN_CHANGE;
if (DOINGSOFTDEP(vp))
softdep_change_linkcnt(ip, 0);
}
pool_put(&namei_pool, cnp->cn_pnbuf);
VN_KNOTE(vp, NOTE_LINK);
VN_KNOTE(dvp, NOTE_WRITE);
out1:
if (dvp != vp)
VOP_UNLOCK(vp);
out2:
vput(dvp);
return (error);
}
/*
* Rename system call.
* rename("foo", "bar");
* is essentially
* unlink("bar");
* link("foo", "bar");
* unlink("foo");
* but ``atomically''. Can't do full commit without saving state in the
* inode on disk which isn't feasible at this time. Best we can do is
* always guarantee the target exists.
*
* Basic algorithm is:
*
* 1) Bump link count on source while we're linking it to the
* target. This also ensure the inode won't be deleted out
* from underneath us while we work (it may be truncated by
* a concurrent `trunc' or `open' for creation).
* 2) Link source to destination. If destination already exists,
* delete it first.
* 3) Unlink source reference to inode if still around. If a
* directory was moved and the parent of the destination
* is different from the source, patch the ".." entry in the
* directory.
*/
int
ufs_rename(void *v)
{
struct vop_rename_args *ap = v;
struct vnode *tvp = ap->a_tvp;
struct vnode *tdvp = ap->a_tdvp;
struct vnode *fvp = ap->a_fvp;
struct vnode *fdvp = ap->a_fdvp;
struct componentname *tcnp = ap->a_tcnp;
struct componentname *fcnp = ap->a_fcnp;
struct inode *ip, *xp, *dp;
struct direct newdir;
int doingdirectory = 0, oldparent = 0, newparent = 0;
int error = 0;
#ifdef DIAGNOSTIC
if ((tcnp->cn_flags & HASBUF) == 0 ||
(fcnp->cn_flags & HASBUF) == 0)
panic("ufs_rename: no name");
#endif
/*
* Check for cross-device rename.
*/
if ((fvp->v_mount != tdvp->v_mount) ||
(tvp && (fvp->v_mount != tvp->v_mount))) {
error = EXDEV;
abortit:
VOP_ABORTOP(tdvp, tcnp);
if (tdvp == tvp)
vrele(tdvp);
else
vput(tdvp);
if (tvp)
vput(tvp);
VOP_ABORTOP(fdvp, fcnp);
vrele(fdvp);
vrele(fvp);
return (error);
}
if (tvp && ((DIP(VTOI(tvp), flags) & (IMMUTABLE | APPEND)) ||
(DIP(VTOI(tdvp), flags) & APPEND))) {
error = EPERM;
goto abortit;
}
/*
* Check if just deleting a link name or if we've lost a race.
* If another process completes the same rename after we've looked
* up the source and have blocked looking up the target, then the
* source and target inodes may be identical now although the
* names were never linked.
*/
if (fvp == tvp) {
if (fvp->v_type == VDIR) {
/*
* Linked directories are impossible, so we must
* have lost the race. Pretend that the rename
* completed before the lookup.
*/
error = ENOENT;
goto abortit;
}
/* Release destination completely. */
VOP_ABORTOP(tdvp, tcnp);
vput(tdvp);
vput(tvp);
/*
* Delete source. There is another race now that everything
* is unlocked, but this doesn't cause any new complications.
* relookup() may find a file that is unrelated to the
* original one, or it may fail. Too bad.
*/
vrele(fvp);
fcnp->cn_flags &= ~MODMASK;
fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
if ((fcnp->cn_flags & SAVESTART) == 0)
panic("ufs_rename: lost from startdir");
fcnp->cn_nameiop = DELETE;
if ((error = vfs_relookup(fdvp, &fvp, fcnp)) != 0)
return (error); /* relookup did vrele() */
vrele(fdvp);
return (VOP_REMOVE(fdvp, fvp, fcnp));
}
if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0)
goto abortit;
/* fvp, tdvp, tvp now locked */
dp = VTOI(fdvp);
ip = VTOI(fvp);
if ((nlink_t) DIP(ip, nlink) >= LINK_MAX) {
VOP_UNLOCK(fvp);
error = EMLINK;
goto abortit;
}
if ((DIP(ip, flags) & (IMMUTABLE | APPEND)) ||
(DIP(dp, flags) & APPEND)) {
VOP_UNLOCK(fvp);
error = EPERM;
goto abortit;
}
if ((DIP(ip, mode) & IFMT) == IFDIR) {
error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_proc);
if (!error && tvp)
error = VOP_ACCESS(tvp, VWRITE, tcnp->cn_cred, tcnp->cn_proc);
if (error) {
VOP_UNLOCK(fvp);
error = EACCES;
goto abortit;
}
/*
* Avoid ".", "..", and aliases of "." for obvious reasons.
*/
if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
dp == ip ||
(fcnp->cn_flags & ISDOTDOT) ||
(tcnp->cn_flags & ISDOTDOT) ||
(ip->i_flag & IN_RENAME)) {
VOP_UNLOCK(fvp);
error = EINVAL;
goto abortit;
}
ip->i_flag |= IN_RENAME;
oldparent = dp->i_number;
doingdirectory = 1;
}
VN_KNOTE(fdvp, NOTE_WRITE); /* XXX right place? */
/*
* When the target exists, both the directory
* and target vnodes are returned locked.
*/
dp = VTOI(tdvp);
xp = NULL;
if (tvp)
xp = VTOI(tvp);
/*
* 1) Bump link count while we're moving stuff
* around. If we crash somewhere before
* completing our work, the link count
* may be wrong, but correctable.
*/
ip->i_effnlink++;
DIP_ADD(ip, nlink, 1);
ip->i_flag |= IN_CHANGE;
if (DOINGSOFTDEP(fvp))
softdep_change_linkcnt(ip, 0);
if ((error = UFS_UPDATE(ip, !DOINGSOFTDEP(fvp))) != 0) {
VOP_UNLOCK(fvp);
goto bad;
}
/*
* If ".." must be changed (ie the directory gets a new
* parent) then the source directory must not be in the
* directory hierarchy above the target, as this would
* orphan everything below the source directory. Also
* the user must have write permission in the source so
* as to be able to change "..". We must repeat the call
* to namei, as the parent directory is unlocked by the
* call to checkpath().
*/
error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_proc);
VOP_UNLOCK(fvp);
/* tdvp and tvp locked */
if (oldparent != dp->i_number)
newparent = dp->i_number;
if (doingdirectory && newparent) {
if (error) /* write access check above */
goto bad;
if (xp != NULL)
vput(tvp);
/*
* Compensate for the reference ufs_checkpath() loses.
*/
vref(tdvp);
/* Only tdvp is locked */
if ((error = ufs_checkpath(ip, dp, tcnp->cn_cred)) != 0) {
vrele(tdvp);
goto out;
}
if ((tcnp->cn_flags & SAVESTART) == 0)
panic("ufs_rename: lost to startdir");
if ((error = vfs_relookup(tdvp, &tvp, tcnp)) != 0)
goto out;
vrele(tdvp); /* relookup() acquired a reference */
dp = VTOI(tdvp);
xp = NULL;
if (tvp)
xp = VTOI(tvp);
}
/*
* 2) If target doesn't exist, link the target
* to the source and unlink the source.
* Otherwise, rewrite the target directory
* entry to reference the source inode and
* expunge the original entry's existence.
*/
if (xp == NULL) {
if (dp->i_dev != ip->i_dev)
panic("rename: EXDEV");
/*
* Account for ".." in new directory.
* When source and destination have the same
* parent we don't fool with the link count.
*/
if (doingdirectory && newparent) {
if ((nlink_t) DIP(dp, nlink) >= LINK_MAX) {
error = EMLINK;
goto bad;
}
dp->i_effnlink++;
DIP_ADD(dp, nlink, 1);
dp->i_flag |= IN_CHANGE;
if (DOINGSOFTDEP(tdvp))
softdep_change_linkcnt(dp, 0);
if ((error = UFS_UPDATE(dp, !DOINGSOFTDEP(tdvp)))
!= 0) {
dp->i_effnlink--;
DIP_ADD(dp, nlink, -1);
dp->i_flag |= IN_CHANGE;
if (DOINGSOFTDEP(tdvp))
softdep_change_linkcnt(dp, 0);
goto bad;
}
}
ufs_makedirentry(ip, tcnp, &newdir);
if ((error = ufs_direnter(tdvp, NULL, &newdir, tcnp, NULL)) != 0) {
if (doingdirectory && newparent) {
dp->i_effnlink--;
DIP_ADD(dp, nlink, -1);
dp->i_flag |= IN_CHANGE;
if (DOINGSOFTDEP(tdvp))
softdep_change_linkcnt(dp, 0);
(void)UFS_UPDATE(dp, 1);
}
goto bad;
}
VN_KNOTE(tdvp, NOTE_WRITE);
vput(tdvp);
} else {
if (xp->i_dev != dp->i_dev || xp->i_dev != ip->i_dev)
panic("rename: EXDEV");
/*
* Short circuit rename(foo, foo).
*/
if (xp->i_number == ip->i_number)
panic("ufs_rename: same file");
/*
* If the parent directory is "sticky", then the user must
* own the parent directory, or the destination of the rename,
* otherwise the destination may not be changed (except by
* root). This implements append-only directories.
*/
if ((DIP(dp, mode) & S_ISTXT) && tcnp->cn_cred->cr_uid != 0 &&
tcnp->cn_cred->cr_uid != DIP(dp, uid) &&
DIP(xp, uid )!= tcnp->cn_cred->cr_uid &&
!vnoperm(tdvp)) {
error = EPERM;
goto bad;
}
/*
* Target must be empty if a directory and have no links
* to it. Also, ensure source and target are compatible
* (both directories, or both not directories).
*/
if ((DIP(xp, mode) & IFMT) == IFDIR) {
if (xp->i_effnlink > 2 ||
!ufs_dirempty(xp, dp->i_number, tcnp->cn_cred)) {
error = ENOTEMPTY;
goto bad;
}
if (!doingdirectory) {
error = ENOTDIR;
goto bad;
}
cache_purge(tdvp);