/*
* Rmdir system call.
*/
int
ufs_rmdir(void *v)
{
struct vop_rmdir_args *ap = v;
struct vnode *vp = ap->a_vp;
struct vnode *dvp = ap->a_dvp;
struct componentname *cnp = ap->a_cnp;
struct inode *ip, *dp;
int error;
ip = VTOI(vp);
dp = VTOI(dvp);
/*
* No rmdir "." or of mounted on directories.
*/
if (dp == ip || vp->v_mountedhere != NULL) {
if (dp == ip)
vrele(dvp);
else
vput(dvp);
vput(vp);
return (EINVAL);
}
/*
* Do not remove a directory that is in the process of being renamed.
* Verify the directory is empty (and valid). Rmdir ".." will not be
* valid since ".." will contain a reference to the current directory
* and thus be non-empty.
*/
error = 0;
if (ip->i_flag & IN_RENAME) {
error = EINVAL;
goto out;
}
if (ip->i_effnlink != 2 ||
!ufs_dirempty(ip, dp->i_number, cnp->cn_cred)) {
error = ENOTEMPTY;
goto out;
}
if ((DIP(dp, flags) & APPEND) ||
(DIP(ip, flags) & (IMMUTABLE | APPEND))) {
error = EPERM;
goto out;
}
/*
* Delete reference to directory before purging
* inode. If we crash in between, the directory
* will be reattached to lost+found,
*/
dp->i_effnlink--;
ip->i_effnlink--;
if (DOINGSOFTDEP(vp)) {
softdep_change_linkcnt(dp, 0);
softdep_change_linkcnt(ip, 0);
}
if ((error = ufs_dirremove(dvp, ip, cnp->cn_flags, 1)) != 0) {
dp->i_effnlink++;
ip->i_effnlink++;
if (DOINGSOFTDEP(vp)) {
softdep_change_linkcnt(dp, 0);
softdep_change_linkcnt(ip, 0);
}
goto out;
}
VN_KNOTE(dvp, NOTE_WRITE | NOTE_LINK);
cache_purge(dvp);
/*
* Truncate inode. The only stuff left in the directory is "." and
* "..". The "." reference is inconsequential since we are quashing
* it. The soft dependency code will arrange to do these operations
* after the parent directory entry has been deleted on disk, so
* when running with that code we avoid doing them now.
*/
if (!DOINGSOFTDEP(vp)) {
int ioflag;
DIP_ADD(dp, nlink, -1);
dp->i_flag |= IN_CHANGE;
DIP_ADD(ip, nlink, -1);
ip->i_flag |= IN_CHANGE;
ioflag = DOINGASYNC(vp) ? 0 : IO_SYNC;
error = UFS_TRUNCATE(ip, (off_t)0, ioflag, cnp->cn_cred);
}
cache_purge(vp);
#ifdef UFS_DIRHASH
/* Kill any active hash; i_effnlink == 0, so it will not come back. */
if (ip->i_dirhash != NULL)
ufsdirhash_free(ip);
#endif
out:
VN_KNOTE(vp, NOTE_DELETE);
vput(dvp);
vput(vp);
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 proc *p = fcnp->cn_proc;
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, p)) != 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, 0);
error = EMLINK;
goto abortit;
}
if ((DIP(ip, flags) & (IMMUTABLE | APPEND)) ||
(DIP(dp, flags) & APPEND)) {
VOP_UNLOCK(fvp, 0);
error = EPERM;
goto abortit;
}
if ((DIP(ip, mode) & IFMT) == IFDIR) {
error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred);
if (!error && tvp)
error = VOP_ACCESS(tvp, VWRITE, tcnp->cn_cred);
if (error) {
VOP_UNLOCK(fvp, 0);
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, 0);
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, 0);
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);
VOP_UNLOCK(fvp, 0);
/* 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) {
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);
} else if (doingdirectory) {
error = EISDIR;
goto bad;
}
if ((error = ufs_dirrewrite(dp, xp, ip->i_number,
IFTODT(DIP(ip, mode)), (doingdirectory && newparent) ?
newparent : doingdirectory)) != 0)
goto bad;
if (doingdirectory) {
if (!newparent) {
dp->i_effnlink--;
if (DOINGSOFTDEP(tdvp))
softdep_change_linkcnt(dp, 0);
}
xp->i_effnlink--;
if (DOINGSOFTDEP(tvp))
softdep_change_linkcnt(xp, 0);
}
if (doingdirectory && !DOINGSOFTDEP(tvp)) {
/*
* Truncate inode. The only stuff left in the directory
* is "." and "..". The "." reference is inconsequential
* since we are quashing it. We have removed the "."
* reference and the reference in the parent directory,
* but there may be other hard links. The soft
* dependency code will arrange to do these operations
* after the parent directory entry has been deleted on
* disk, so when running with that code we avoid doing
* them now.
*/
if (!newparent) {
DIP_ADD(dp, nlink, -1);
dp->i_flag |= IN_CHANGE;
}
DIP_ADD(xp, nlink, -1);
xp->i_flag |= IN_CHANGE;
if ((error = UFS_TRUNCATE(VTOI(tvp), (off_t)0, IO_SYNC,
tcnp->cn_cred)) != 0)
goto bad;
}
VN_KNOTE(tdvp, NOTE_WRITE);
vput(tdvp);
VN_KNOTE(tvp, NOTE_DELETE);
vput(tvp);
xp = NULL;
}
/*
* 3) Unlink the source.
*/
fcnp->cn_flags &= ~MODMASK;
fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
if ((fcnp->cn_flags & SAVESTART) == 0)
panic("ufs_rename: lost from startdir");
if ((error = vfs_relookup(fdvp, &fvp, fcnp)) != 0) {
vrele(ap->a_fvp);
return (error);
}
vrele(fdvp);
if (fvp == NULL) {
/*
* From name has disappeared.
*/
if (doingdirectory)
panic("ufs_rename: lost dir entry");
vrele(ap->a_fvp);
return (0);
}
xp = VTOI(fvp);
dp = VTOI(fdvp);
/*
* Ensure that the directory entry still exists and has not
* changed while the new name has been entered. If the source is
* a file then the entry may have been unlinked or renamed. In
* either case there is no further work to be done. If the source
* is a directory then it cannot have been rmdir'ed; the IN_RENAME
* flag ensures that it cannot be moved by another rename or removed
* by a rmdir.
*/
if (xp != ip) {
if (doingdirectory)
panic("ufs_rename: lost dir entry");
} else {
/*
* If the source is a directory with a
* new parent, the link count of the old
* parent directory must be decremented
* and ".." set to point to the new parent.
*/
if (doingdirectory && newparent) {
xp->i_offset = mastertemplate.dot_reclen;
ufs_dirrewrite(xp, dp, newparent, DT_DIR, 0);
cache_purge(fdvp);
}
error = ufs_dirremove(fdvp, xp, fcnp->cn_flags, 0);
xp->i_flag &= ~IN_RENAME;
}
VN_KNOTE(fvp, NOTE_RENAME);
if (dp)
vput(fdvp);
if (xp)
vput(fvp);
vrele(ap->a_fvp);
return (error);
bad:
if (xp)
vput(ITOV(xp));
vput(ITOV(dp));
out:
vrele(fdvp);
if (doingdirectory)
ip->i_flag &= ~IN_RENAME;
if (vn_lock(fvp, LK_EXCLUSIVE, p) == 0) {
ip->i_effnlink--;
DIP_ADD(ip, nlink, -1);
ip->i_flag |= IN_CHANGE;
ip->i_flag &= ~IN_RENAME;
if (DOINGSOFTDEP(fvp))
softdep_change_linkcnt(ip, 0);
vput(fvp);
} else
vrele(fvp);
return (error);
}
int
ufs_rmdir(void *v)
{
struct vop_rmdir_args /* {
struct vnode *a_dvp;
struct vnode *a_vp;
struct componentname *a_cnp;
} */ *ap = v;
struct vnode *vp, *dvp;
struct componentname *cnp;
struct inode *ip, *dp;
int error;
struct ufs_lookup_results *ulr;
vp = ap->a_vp;
dvp = ap->a_dvp;
cnp = ap->a_cnp;
ip = VTOI(vp);
dp = VTOI(dvp);
/* XXX should handle this material another way */
ulr = &dp->i_crap;
UFS_CHECK_CRAPCOUNTER(dp);
/*
* No rmdir "." or of mounted directories please.
*/
if (dp == ip || vp->v_mountedhere != NULL) {
if (dp == ip)
vrele(dvp);
else
vput(dvp);
vput(vp);
return (EINVAL);
}
fstrans_start(dvp->v_mount, FSTRANS_SHARED);
/*
* Do not remove a directory that is in the process of being renamed.
* Verify that the directory is empty (and valid). (Rmdir ".." won't
* be valid since ".." will contain a reference to the current
* directory and thus be non-empty.)
*/
error = 0;
if (ip->i_nlink != 2 ||
!ufs_dirempty(ip, dp->i_number, cnp->cn_cred)) {
error = ENOTEMPTY;
goto out;
}
if ((dp->i_flags & APPEND) ||
(ip->i_flags & (IMMUTABLE | APPEND))) {
error = EPERM;
goto out;
}
error = UFS_WAPBL_BEGIN(dvp->v_mount);
if (error)
goto out;
/*
* Delete reference to directory before purging
* inode. If we crash in between, the directory
* will be reattached to lost+found,
*/
error = ufs_dirremove(dvp, ulr, ip, cnp->cn_flags, 1);
if (error) {
UFS_WAPBL_END(dvp->v_mount);
goto out;
}
VN_KNOTE(dvp, NOTE_WRITE | NOTE_LINK);
cache_purge(dvp);
/*
* Truncate inode. The only stuff left in the directory is "." and
* "..". The "." reference is inconsequential since we're quashing
* it.
*/
dp->i_nlink--;
DIP_ASSIGN(dp, nlink, dp->i_nlink);
dp->i_flag |= IN_CHANGE;
UFS_WAPBL_UPDATE(dvp, NULL, NULL, UPDATE_DIROP);
ip->i_nlink--;
DIP_ASSIGN(ip, nlink, ip->i_nlink);
ip->i_flag |= IN_CHANGE;
error = UFS_TRUNCATE(vp, (off_t)0, IO_SYNC, cnp->cn_cred);
cache_purge(vp);
/*
* Unlock the log while we still have reference to unlinked
* directory vp so that it will not get locked for recycling
*/
UFS_WAPBL_END(dvp->v_mount);
#ifdef UFS_DIRHASH
if (ip->i_dirhash != NULL)
ufsdirhash_free(ip);
#endif
out:
VN_KNOTE(vp, NOTE_DELETE);
vput(vp);
fstrans_done(dvp->v_mount);
vput(dvp);
return (error);
}