示例#1
0
/*
 *	discard preallocated blocks
 */
int
ext2_inactive(struct vop_inactive_args *ap)
{
	struct vnode *vp = ap->a_vp;
	struct inode *ip = VTOI(vp);
	struct thread *td = ap->a_td;
	int mode, error = 0;

	/*
	 * Ignore inodes related to stale file handles.
	 */
	if (ip->i_mode == 0)
		goto out;
	if (ip->i_nlink <= 0) {
		error = ext2_truncate(vp, (off_t)0, 0, NOCRED, td);
		ip->i_rdev = 0;
		mode = ip->i_mode;
		ip->i_mode = 0;
		ip->i_flag |= IN_CHANGE | IN_UPDATE;
		ext2_vfree(vp, ip->i_number, mode);
	}
	if (ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE))
		ext2_update(vp, 0);
out:
	/*
	 * If we are done with the inode, reclaim it
	 * so that it can be reused immediately.
	 */
	if (ip->i_mode == 0)
		vrecycle(vp);
	return (error);
}
示例#2
0
/* ARGSUSED */
static int
ext2_fsync(struct vop_fsync_args *ap)
{
	/*
	 * Flush all dirty buffers associated with a vnode.
	 */

	vop_stdfsync(ap);

	return (ext2_update(ap->a_vp, ap->a_waitfor == MNT_WAIT));
}
示例#3
0
/*
 * Reclaim an inode so that it can be used for other purposes.
 */
int
ext2_reclaim(struct vop_reclaim_args *ap)
{
	struct inode *ip;
	struct vnode *vp = ap->a_vp;

	ip = VTOI(vp);
	if (ip->i_flag & IN_LAZYMOD) {
		ip->i_flag |= IN_MODIFIED;
		ext2_update(vp, 0);
	}
	vfs_hash_remove(vp);
	free(vp->v_data, M_EXT2NODE);
	vp->v_data = 0;
	vnode_destroy_vobject(vp);
	return (0);
}
示例#4
0
/*
 * link vnode call
 */
static int
ext2_link(struct vop_link_args *ap)
{
	struct vnode *vp = ap->a_vp;
	struct vnode *tdvp = ap->a_tdvp;
	struct componentname *cnp = ap->a_cnp;
	struct inode *ip;
	int error;

#ifdef DIAGNOSTIC
	if ((cnp->cn_flags & HASBUF) == 0)
		panic("ext2_link: no name");
#endif
	if (tdvp->v_mount != vp->v_mount) {
		error = EXDEV;
		goto out;
	}
	ip = VTOI(vp);
	if ((nlink_t)ip->i_nlink >= EXT2_LINK_MAX) {
		error = EMLINK;
		goto out;
	}
	if (ip->i_flags & (IMMUTABLE | APPEND)) {
		error = EPERM;
		goto out;
	}
	ip->i_nlink++;
	ip->i_flag |= IN_CHANGE;
	error = ext2_update(vp, !DOINGASYNC(vp));
	if (!error)
		error = ext2_direnter(ip, tdvp, cnp);
	if (error) {
		ip->i_nlink--;
		ip->i_flag |= IN_CHANGE;
	}
out:
	return (error);
}
示例#5
0
/*
 * 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.
 */
static int
ext2_rename(struct vop_rename_args *ap)
{
	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 dirtemplate dirbuf;
	int doingdirectory = 0, oldparent = 0, newparent = 0;
	int error = 0;
	u_char namlen;

#ifdef DIAGNOSTIC
	if ((tcnp->cn_flags & HASBUF) == 0 ||
	    (fcnp->cn_flags & HASBUF) == 0)
		panic("ext2_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:
		if (tdvp == tvp)
			vrele(tdvp);
		else
			vput(tdvp);
		if (tvp)
			vput(tvp);
		vrele(fdvp);
		vrele(fvp);
		return (error);
	}

	if (tvp && ((VTOI(tvp)->i_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
	    (VTOI(tdvp)->i_flags & APPEND))) {
		error = EPERM;
		goto abortit;
	}

	/*
	 * Renaming a file to itself has no effect.  The upper layers should
	 * not call us in that case.  Temporarily just warn if they do.
	 */
	if (fvp == tvp) {
		printf("ext2_rename: fvp == tvp (can't happen)\n");
		error = 0;
		goto abortit;
	}

	if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0)
		goto abortit;
	dp = VTOI(fdvp);
	ip = VTOI(fvp);
	if (ip->i_nlink >= EXT2_LINK_MAX) {
 		VOP_UNLOCK(fvp, 0);
 		error = EMLINK;
 		goto abortit;
 	}
	if ((ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND))
	    || (dp->i_flags & APPEND)) {
		VOP_UNLOCK(fvp, 0);
		error = EPERM;
		goto abortit;
	}
	if ((ip->i_mode & IFMT) == IFDIR) {
		/*
		 * Avoid ".", "..", and aliases of "." for obvious reasons.
		 */
		if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
		    dp == ip || (fcnp->cn_flags | 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++;
	}
	vrele(fdvp);

	/*
	 * 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_nlink++;
	ip->i_flag |= IN_CHANGE;
	if ((error = ext2_update(fvp, !DOINGASYNC(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, tcnp->cn_thread);
	VOP_UNLOCK(fvp, 0);
	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);
		error = ext2_checkpath(ip, dp, tcnp->cn_cred);
		if (error)
			goto out;
		VREF(tdvp);
		error = relookup(tdvp, &tvp, tcnp);
		if (error)
			goto out;
		vrele(tdvp);
		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_devvp != ip->i_devvp)
			panic("ext2_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)dp->i_nlink >= EXT2_LINK_MAX) {
				error = EMLINK;
				goto bad;
			}
			dp->i_nlink++;
			dp->i_flag |= IN_CHANGE;
			error = ext2_update(tdvp, !DOINGASYNC(tdvp));
			if (error)
				goto bad;
		}
		error = ext2_direnter(ip, tdvp, tcnp);
		if (error) {
			if (doingdirectory && newparent) {
				dp->i_nlink--;
				dp->i_flag |= IN_CHANGE;
				(void)ext2_update(tdvp, 1);
			}
			goto bad;
		}
		vput(tdvp);
	} else {
		if (xp->i_devvp != dp->i_devvp || xp->i_devvp != ip->i_devvp)
		       panic("ext2_rename: EXDEV");
		/*
		 * Short circuit rename(foo, foo).
		 */
		if (xp->i_number == ip->i_number)
			panic("ext2_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 ((dp->i_mode & S_ISTXT) && tcnp->cn_cred->cr_uid != 0 &&
		    tcnp->cn_cred->cr_uid != dp->i_uid &&
		    xp->i_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 ((xp->i_mode&IFMT) == IFDIR) {
			if (! ext2_dirempty(xp, dp->i_number, tcnp->cn_cred) || 
			    xp->i_nlink > 2) {
				error = ENOTEMPTY;
				goto bad;
			}
			if (!doingdirectory) {
				error = ENOTDIR;
				goto bad;
			}
			cache_purge(tdvp);
		} else if (doingdirectory) {
			error = EISDIR;
			goto bad;
		}
		error = ext2_dirrewrite(dp, ip, tcnp);
		if (error)
			goto bad;
		/*
		 * If the target directory is in the same
		 * directory as the source directory,
		 * decrement the link count on the parent
		 * of the target directory.
		 */
		if (doingdirectory && !newparent) {
		       dp->i_nlink--;
		       dp->i_flag |= IN_CHANGE;
		}
		vput(tdvp);
		/*
		 * Adjust the link count of the target to
		 * reflect the dirrewrite above.  If this is
		 * a directory it is empty and there are
		 * no links to it, so we can squash the inode and
		 * any space associated with it.  We disallowed
		 * renaming over top of a directory with links to
		 * it above, as the remaining link would point to
		 * a directory without "." or ".." entries.
		 */
		xp->i_nlink--;
		if (doingdirectory) {
			if (--xp->i_nlink != 0)
				panic("ext2_rename: linked directory");
			error = ext2_truncate(tvp, (off_t)0, IO_SYNC,
			    tcnp->cn_cred, tcnp->cn_thread);
		}
		xp->i_flag |= IN_CHANGE;
		vput(tvp);
		xp = NULL;
	}

	/*
	 * 3) Unlink the source.
	 */
	fcnp->cn_flags &= ~MODMASK;
	fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
	VREF(fdvp);
	error = relookup(fdvp, &fvp, fcnp);
	if (error == 0)
		vrele(fdvp);
	if (fvp != NULL) {
		xp = VTOI(fvp);
		dp = VTOI(fdvp);
	} else {
		/*
		 * From name has disappeared.
		 */
		if (doingdirectory)
			panic("ext2_rename: lost dir entry");
		vrele(ap->a_fvp);
		return (0);
	}
	/*
	 * 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; its link
	 * count of three would cause a rmdir to fail with ENOTEMPTY.
	 * The IN_RENAME flag ensures that it cannot be moved by another
	 * rename.
	 */
	if (xp != ip) {
		if (doingdirectory)
			panic("ext2_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) {
			dp->i_nlink--;
			dp->i_flag |= IN_CHANGE;
			error = vn_rdwr(UIO_READ, fvp, (caddr_t)&dirbuf,
				sizeof(struct dirtemplate), (off_t)0,
				UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK,
				tcnp->cn_cred, NOCRED, NULL, NULL);
			if (error == 0) {
				/* Like ufs little-endian: */
				namlen = dirbuf.dotdot_type;
				if (namlen != 2 ||
				    dirbuf.dotdot_name[0] != '.' ||
				    dirbuf.dotdot_name[1] != '.') {
					ext2_dirbad(xp, (doff_t)12,
					    "rename: mangled dir");
				} else {
					dirbuf.dotdot_ino = newparent;
					(void) vn_rdwr(UIO_WRITE, fvp,
					    (caddr_t)&dirbuf,
					    sizeof(struct dirtemplate),
					    (off_t)0, UIO_SYSSPACE,
					    IO_NODELOCKED | IO_SYNC |
					    IO_NOMACCHECK, tcnp->cn_cred,
					    NOCRED, NULL, NULL);
					cache_purge(fdvp);
				}
			}
		}
		error = ext2_dirremove(fdvp, fcnp);
		if (!error) {
			xp->i_nlink--;
			xp->i_flag |= IN_CHANGE;
		}
		xp->i_flag &= ~IN_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:
	if (doingdirectory)
		ip->i_flag &= ~IN_RENAME;
	if (vn_lock(fvp, LK_EXCLUSIVE) == 0) {
		ip->i_nlink--;
		ip->i_flag |= IN_CHANGE;
		ip->i_flag &= ~IN_RENAME;
		vput(fvp);
	} else
		vrele(fvp);
	return (error);
}
示例#6
0
/*
 * Set attribute vnode op. called from several syscalls
 */
static int
ext2_setattr(struct vop_setattr_args *ap)
{
	struct vattr *vap = ap->a_vap;
	struct vnode *vp = ap->a_vp;
	struct inode *ip = VTOI(vp);
	struct ucred *cred = ap->a_cred;
	struct thread *td = curthread;
	int error;

	/*
	 * 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) {
		/* Disallow flags not supported by ext2fs. */
		if(vap->va_flags & ~(SF_APPEND | SF_IMMUTABLE | UF_NODUMP))
			return (EOPNOTSUPP);

		if (vp->v_mount->mnt_flag & MNT_RDONLY)
			return (EROFS);
		/*
		 * Callers may only modify the file flags on objects they
		 * have VADMIN rights for.
		 */
		if ((error = VOP_ACCESS(vp, VADMIN, cred, td)))
			return (error);
		/*
		 * Unprivileged processes and privileged processes in
		 * jail() are not permitted to unset system flags, or
		 * modify flags if any system flags are set.
		 * Privileged non-jail processes may not modify system flags
		 * if securelevel > 0 and any existing system flags are set.
		 */
		if (!priv_check_cred(cred, PRIV_VFS_SYSFLAGS, 0)) {
			if (ip->i_flags & (SF_IMMUTABLE | SF_APPEND)) {
				error = securelevel_gt(cred, 0);
				if (error)
					return (error);
			}
		} else {
			if (ip->i_flags & (SF_IMMUTABLE | SF_APPEND) ||
			    ((vap->va_flags ^ ip->i_flags) & SF_SETTABLE))
				return (EPERM);
		}
		ip->i_flags = vap->va_flags;
		ip->i_flag |= IN_CHANGE;
		if (ip->i_flags & (IMMUTABLE | APPEND))
			return (0);
	}
	if (ip->i_flags & (IMMUTABLE | APPEND))
		return (EPERM);
	/*
	 * Go through the fields and update iff 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);
		if ((error = ext2_chown(vp, vap->va_uid, vap->va_gid, cred,
		    td)) != 0)
			return (error);
	}
	if (vap->va_size != VNOVAL) {
		/*
		 * 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 = ext2_truncate(vp, vap->va_size, 0, cred, td)) != 0)
			return (error);
	}
	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
		if (vp->v_mount->mnt_flag & MNT_RDONLY)
			return (EROFS);
		/*
		 * From utimes(2):
		 * If times is NULL, ... The caller must be the owner of
		 * the file, have permission to write the file, or be the
		 * super-user.
		 * If times is non-NULL, ... The caller must be the owner of
		 * the file or be the super-user.
		 */
		if ((error = VOP_ACCESS(vp, VADMIN, cred, td)) &&
		    ((vap->va_vaflags & VA_UTIMES_NULL) == 0 ||
		    (error = VOP_ACCESS(vp, VWRITE, cred, td))))
			return (error);
		if (vap->va_atime.tv_sec != VNOVAL)
			ip->i_flag |= IN_ACCESS;
		if (vap->va_mtime.tv_sec != VNOVAL)
			ip->i_flag |= IN_CHANGE | IN_UPDATE;
		ext2_itimes(vp);
		if (vap->va_atime.tv_sec != VNOVAL) {
			ip->i_atime = vap->va_atime.tv_sec;
			ip->i_atimensec = vap->va_atime.tv_nsec;
		}
		if (vap->va_mtime.tv_sec != VNOVAL) {
			ip->i_mtime = vap->va_mtime.tv_sec;
			ip->i_mtimensec = vap->va_mtime.tv_nsec;
		}
		ip->i_birthtime = vap->va_birthtime.tv_sec;
		ip->i_birthnsec = vap->va_birthtime.tv_nsec;
		error = ext2_update(vp, 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 = ext2_chmod(vp, (int)vap->va_mode, cred, td);
	}
	return (error);
}
示例#7
0
/*
 * Vnode op for writing.
 */
static int
ext2_write(struct vop_write_args *ap)
{
	struct vnode *vp;
	struct uio *uio;
	struct inode *ip;
	struct m_ext2fs *fs;
	struct buf *bp;
	daddr_t lbn;
	off_t osize;
	int blkoffset, error, flags, ioflag, resid, size, seqcount, xfersize;

	ioflag = ap->a_ioflag;
	uio = ap->a_uio;
	vp = ap->a_vp;

	seqcount = ioflag >> IO_SEQSHIFT;
	ip = VTOI(vp);

#ifdef INVARIANTS
	if (uio->uio_rw != UIO_WRITE)
		panic("%s: mode", "ext2_write");
#endif

	switch (vp->v_type) {
	case VREG:
		if (ioflag & IO_APPEND)
			uio->uio_offset = ip->i_size;
		if ((ip->i_flags & APPEND) && uio->uio_offset != ip->i_size)
			return (EPERM);
		/* FALLTHROUGH */
	case VLNK:
		break;
	case VDIR:
		/* XXX differs from ffs -- this is called from ext2_mkdir(). */
		if ((ioflag & IO_SYNC) == 0)
		panic("ext2_write: nonsync dir write");
		break;
	default:
		panic("ext2_write: type %p %d (%jd,%jd)", (void *)vp,
		    vp->v_type, (intmax_t)uio->uio_offset,
		    (intmax_t)uio->uio_resid);
	}

	KASSERT(uio->uio_resid >= 0, ("ext2_write: uio->uio_resid < 0"));
	KASSERT(uio->uio_offset >= 0, ("ext2_write: uio->uio_offset < 0"));
	fs = ip->i_e2fs;
	if ((uoff_t)uio->uio_offset + uio->uio_resid > fs->e2fs_maxfilesize)
		return (EFBIG);
	/*
	 * Maybe this should be above the vnode op call, but so long as
	 * file servers have no limits, I don't think it matters.
	 */
	if (vn_rlimit_fsize(vp, uio, uio->uio_td))
		return (EFBIG);

	resid = uio->uio_resid;
	osize = ip->i_size;
	if (seqcount > BA_SEQMAX)
		flags = BA_SEQMAX << BA_SEQSHIFT;
	else
		flags = seqcount << BA_SEQSHIFT;
	if ((ioflag & IO_SYNC) && !DOINGASYNC(vp))
		flags |= IO_SYNC;

	for (error = 0; uio->uio_resid > 0;) {
		lbn = lblkno(fs, uio->uio_offset);
		blkoffset = blkoff(fs, uio->uio_offset);
		xfersize = fs->e2fs_fsize - blkoffset;
		if (uio->uio_resid < xfersize)
			xfersize = uio->uio_resid;
		if (uio->uio_offset + xfersize > ip->i_size)
			vnode_pager_setsize(vp, uio->uio_offset + xfersize);

                /*
		 * We must perform a read-before-write if the transfer size
		 * does not cover the entire buffer.
                 */
		if (fs->e2fs_bsize > xfersize)
			flags |= BA_CLRBUF;
		else
			flags &= ~BA_CLRBUF;
		error = ext2_balloc(ip, lbn, blkoffset + xfersize,
		    ap->a_cred, &bp, flags);
		if (error != 0)
			break;

		/*
		 * If the buffer is not valid and we did not clear garbage
		 * out above, we have to do so here even though the write
		 * covers the entire buffer in order to avoid a mmap()/write
		 * race where another process may see the garbage prior to
		 * the uiomove() for a write replacing it.
		 */
		if ((bp->b_flags & B_CACHE) == 0 && fs->e2fs_bsize <= xfersize)
			vfs_bio_clrbuf(bp);
		if ((ioflag & (IO_SYNC|IO_INVAL)) == (IO_SYNC|IO_INVAL))
			bp->b_flags |= B_NOCACHE;
		if (uio->uio_offset + xfersize > ip->i_size)
			ip->i_size = uio->uio_offset + xfersize;
		size = blksize(fs, ip, lbn) - bp->b_resid;
		if (size < xfersize)
			xfersize = size;

		error =
		    uiomove((char *)bp->b_data + blkoffset, (int)xfersize, uio);
		if (ioflag & (IO_VMIO|IO_DIRECT)) {
			bp->b_flags |= B_RELBUF;
		}

		/*
		 * If IO_SYNC each buffer is written synchronously.  Otherwise
		 * if we have a severe page deficiency write the buffer
		 * asynchronously.  Otherwise try to cluster, and if that
		 * doesn't do it then either do an async write (if O_DIRECT),
		 * or a delayed write (if not).
		 */
		if (ioflag & IO_SYNC) {
			(void)bwrite(bp);
		} else if (vm_page_count_severe() ||
		    buf_dirty_count_severe() ||
		    (ioflag & IO_ASYNC)) {
			bp->b_flags |= B_CLUSTEROK;
			bawrite(bp);
		} else if (xfersize + blkoffset == fs->e2fs_fsize) {
			if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERW) == 0) {
				bp->b_flags |= B_CLUSTEROK;
				cluster_write(vp, bp, ip->i_size, seqcount, 0);
			} else {
				bawrite(bp);
			}
		} else if (ioflag & IO_DIRECT) {
			bp->b_flags |= B_CLUSTEROK;
			bawrite(bp);
		} else {
			bp->b_flags |= B_CLUSTEROK;
			bdwrite(bp);
		}
		if (error || xfersize == 0)
			break;
	}
	/*
	 * If we successfully wrote any data, and we are not the superuser
	 * we clear the setuid and setgid bits as a precaution against
	 * tampering.
	 */
	if ((ip->i_mode & (ISUID | ISGID)) && resid > uio->uio_resid &&
	    ap->a_cred) {
		if (priv_check_cred(ap->a_cred, PRIV_VFS_RETAINSUGID, 0))
			ip->i_mode &= ~(ISUID | ISGID);
	}
	if (error) {
		if (ioflag & IO_UNIT) {
			(void)ext2_truncate(vp, osize,
			    ioflag & IO_SYNC, ap->a_cred, uio->uio_td);
			uio->uio_offset -= resid - uio->uio_resid;
			uio->uio_resid = resid;
		}
	}
	if (uio->uio_resid != resid) {
               ip->i_flag |= IN_CHANGE | IN_UPDATE;
               if (ioflag & IO_SYNC)
                       error = ext2_update(vp, 1);
       }
	return (error);
}
示例#8
0
/*
 * Allocate a new inode.
 */
static int
ext2_makeinode(int mode, struct vnode *dvp, struct vnode **vpp,
    struct componentname *cnp)
{
	struct inode *ip, *pdir;
	struct vnode *tvp;
	int error;

	pdir = VTOI(dvp);
#ifdef DIAGNOSTIC
	if ((cnp->cn_flags & HASBUF) == 0)
		panic("ext2_makeinode: no name");
#endif
	*vpp = NULL;
	if ((mode & IFMT) == 0)
		mode |= IFREG;

	error = ext2_valloc(dvp, mode, cnp->cn_cred, &tvp);
	if (error) {
		return (error);
	}
	ip = VTOI(tvp);
	ip->i_gid = pdir->i_gid;
#ifdef SUIDDIR
	{
		/*
		 * if we are
		 * not the owner of the directory,
		 * and we are hacking owners here, (only do this where told to)
		 * and we are not giving it TOO root, (would subvert quotas)
		 * then go ahead and give it to the other user.
		 * Note that this drops off the execute bits for security.
		 */
		if ( (dvp->v_mount->mnt_flag & MNT_SUIDDIR) &&
		     (pdir->i_mode & ISUID) &&
		     (pdir->i_uid != cnp->cn_cred->cr_uid) && pdir->i_uid) {
			ip->i_uid = pdir->i_uid;
			mode &= ~07111;
		} else {
			ip->i_uid = cnp->cn_cred->cr_uid;
		}
	}
#else
	ip->i_uid = cnp->cn_cred->cr_uid;
#endif
	ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
	ip->i_mode = mode;
	tvp->v_type = IFTOVT(mode);	/* Rest init'd in getnewvnode(). */
	ip->i_nlink = 1;
	if ((ip->i_mode & ISGID) && !groupmember(ip->i_gid, cnp->cn_cred)) {
		if (priv_check_cred(cnp->cn_cred, PRIV_VFS_RETAINSUGID, 0))
			ip->i_mode &= ~ISGID;
	}

	if (cnp->cn_flags & ISWHITEOUT)
		ip->i_flags |= UF_OPAQUE;

	/*
	 * Make sure inode goes to disk before directory entry.
	 */
	error = ext2_update(tvp, !DOINGASYNC(tvp));
	if (error)
		goto bad;
	error = ext2_direnter(ip, dvp, cnp);
	if (error)
		goto bad;

	*vpp = tvp;
	return (0);

bad:
	/*
	 * Write error occurred trying to update the inode
	 * or the directory so must deallocate the inode.
	 */
	ip->i_nlink = 0;
	ip->i_flag |= IN_CHANGE;
	vput(tvp);
	return (error);
}
示例#9
0
/*
 * Mkdir system call
 */
static int
ext2_mkdir(struct vop_mkdir_args *ap)
{
	struct vnode *dvp = ap->a_dvp;
	struct vattr *vap = ap->a_vap;
	struct componentname *cnp = ap->a_cnp;
	struct inode *ip, *dp;
	struct vnode *tvp;
	struct dirtemplate dirtemplate, *dtp;
	int error, dmode;

#ifdef DIAGNOSTIC
	if ((cnp->cn_flags & HASBUF) == 0)
		panic("ext2_mkdir: no name");
#endif
	dp = VTOI(dvp);
	if ((nlink_t)dp->i_nlink >= EXT2_LINK_MAX) {
		error = EMLINK;
		goto out;
	}
	dmode = vap->va_mode & 0777;
	dmode |= IFDIR;
	/*
	 * Must simulate part of ext2_makeinode here to acquire the inode,
	 * but not have it entered in the parent directory. The entry is
	 * made later after writing "." and ".." entries.
	 */
	error = ext2_valloc(dvp, dmode, cnp->cn_cred, &tvp);
	if (error)
		goto out;
	ip = VTOI(tvp);
	ip->i_gid = dp->i_gid;
#ifdef SUIDDIR
	{
		/*
		 * if we are hacking owners here, (only do this where told to)
		 * and we are not giving it TOO root, (would subvert quotas)
		 * then go ahead and give it to the other user.
		 * The new directory also inherits the SUID bit. 
		 * If user's UID and dir UID are the same,
		 * 'give it away' so that the SUID is still forced on.
		 */
		if ( (dvp->v_mount->mnt_flag & MNT_SUIDDIR) &&
		   (dp->i_mode & ISUID) && dp->i_uid) {
			dmode |= ISUID;
			ip->i_uid = dp->i_uid;
		} else {
			ip->i_uid = cnp->cn_cred->cr_uid;
		}
	}
#else
	ip->i_uid = cnp->cn_cred->cr_uid;
#endif
	ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
	ip->i_mode = dmode;
	tvp->v_type = VDIR;	/* Rest init'd in getnewvnode(). */
	ip->i_nlink = 2;
	if (cnp->cn_flags & ISWHITEOUT)
		ip->i_flags |= UF_OPAQUE;
	error = ext2_update(tvp, 1);

	/*
	 * Bump link count in parent directory
	 * to reflect work done below.  Should
	 * be done before reference is created
	 * so reparation is possible if we crash.
	 */
	dp->i_nlink++;
	dp->i_flag |= IN_CHANGE;
	error = ext2_update(dvp, !DOINGASYNC(dvp));
	if (error)
		goto bad;

	/* Initialize directory with "." and ".." from static template. */
	if (EXT2_HAS_INCOMPAT_FEATURE(ip->i_e2fs,
	    EXT2F_INCOMPAT_FTYPE))
		dtp = &mastertemplate;
	else
		dtp = &omastertemplate;
	dirtemplate = *dtp;
	dirtemplate.dot_ino = ip->i_number;
	dirtemplate.dotdot_ino = dp->i_number;
	/* note that in ext2 DIRBLKSIZ == blocksize, not DEV_BSIZE 
	 * so let's just redefine it - for this function only
	 */
#undef  DIRBLKSIZ 
#define DIRBLKSIZ  VTOI(dvp)->i_e2fs->e2fs_bsize
	dirtemplate.dotdot_reclen = DIRBLKSIZ - 12;
	error = vn_rdwr(UIO_WRITE, tvp, (caddr_t)&dirtemplate,
	    sizeof(dirtemplate), (off_t)0, UIO_SYSSPACE,
	    IO_NODELOCKED | IO_SYNC | IO_NOMACCHECK, cnp->cn_cred, NOCRED,
	    NULL, NULL);
	if (error) {
		dp->i_nlink--;
		dp->i_flag |= IN_CHANGE;
		goto bad;
	}
	if (DIRBLKSIZ > VFSTOEXT2(dvp->v_mount)->um_mountp->mnt_stat.f_bsize)
		/* XXX should grow with balloc() */
		panic("ext2_mkdir: blksize");
	else {
		ip->i_size = DIRBLKSIZ;
		ip->i_flag |= IN_CHANGE;
	}

	/* Directory set up, now install its entry in the parent directory. */
	error = ext2_direnter(ip, dvp, cnp);
	if (error) {
		dp->i_nlink--;
		dp->i_flag |= IN_CHANGE;
	}
bad:
	/*
	 * No need to do an explicit VOP_TRUNCATE here, vrele will do this
	 * for us because we set the link count to 0.
	 */
	if (error) {
		ip->i_nlink = 0;
		ip->i_flag |= IN_CHANGE;
		vput(tvp);
	} else
		*ap->a_vpp = tvp;
out:
	return (error);
#undef  DIRBLKSIZ
#define DIRBLKSIZ  DEV_BSIZE
}
示例#10
0
/*
 * Truncate the inode oip to at most length size, freeing the
 * disk blocks.
 */
int
ext2_truncate(struct vnode *vp, off_t length, int flags, struct ucred *cred,
    struct thread *td)
{
	struct vnode *ovp = vp;
	int32_t lastblock;
	struct inode *oip;
	int32_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR];
	uint32_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
	struct m_ext2fs *fs;
	struct buf *bp;
	int offset, size, level;
	e4fs_daddr_t count, nblocks, blocksreleased = 0;
	int error, i, allerror;
	off_t osize;
#ifdef INVARIANTS
	struct bufobj *bo;
#endif

	oip = VTOI(ovp);
#ifdef INVARIANTS
	bo = &ovp->v_bufobj;
#endif

	ASSERT_VOP_LOCKED(vp, "ext2_truncate");	

	if (length < 0)
	    return (EINVAL);

	if (ovp->v_type == VLNK &&
	    oip->i_size < ovp->v_mount->mnt_maxsymlinklen) {
#ifdef INVARIANTS
		if (length != 0)
			panic("ext2_truncate: partial truncate of symlink");
#endif
		bzero((char *)&oip->i_shortlink, (u_int)oip->i_size);
		oip->i_size = 0;
		oip->i_flag |= IN_CHANGE | IN_UPDATE;
		return (ext2_update(ovp, 1));
	}
	if (oip->i_size == length) {
		oip->i_flag |= IN_CHANGE | IN_UPDATE;
		return (ext2_update(ovp, 0));
	}
	fs = oip->i_e2fs;
	osize = oip->i_size;
	/*
	 * Lengthen the size of the file. We must ensure that the
	 * last byte of the file is allocated. Since the smallest
	 * value of osize is 0, length will be at least 1.
	 */
	if (osize < length) {
		if (length > oip->i_e2fs->e2fs_maxfilesize)
			return (EFBIG);
		vnode_pager_setsize(ovp, length);
		offset = blkoff(fs, length - 1);
		lbn = lblkno(fs, length - 1);
		flags |= BA_CLRBUF;
		error = ext2_balloc(oip, lbn, offset + 1, cred, &bp, flags);
		if (error) {
			vnode_pager_setsize(vp, osize);
			return (error);
		}
		oip->i_size = length;
		if (bp->b_bufsize == fs->e2fs_bsize)
			bp->b_flags |= B_CLUSTEROK;
		if (flags & IO_SYNC)
			bwrite(bp);
		else if (DOINGASYNC(ovp))
			bdwrite(bp);
		else
			bawrite(bp);
		oip->i_flag |= IN_CHANGE | IN_UPDATE;
		return (ext2_update(ovp, !DOINGASYNC(ovp)));
	}
	/*
	 * Shorten the size of the file. If the file is not being
	 * truncated to a block boundry, the contents of the
	 * partial block following the end of the file must be
	 * zero'ed in case it ever become accessible again because
	 * of subsequent file growth.
	 */
	/* I don't understand the comment above */
	offset = blkoff(fs, length);
	if (offset == 0) {
		oip->i_size = length;
	} else {
		lbn = lblkno(fs, length);
		flags |= BA_CLRBUF;
		error = ext2_balloc(oip, lbn, offset, cred, &bp, flags);
		if (error)
			return (error);
		oip->i_size = length;
		size = blksize(fs, oip, lbn);
		bzero((char *)bp->b_data + offset, (u_int)(size - offset));
		allocbuf(bp, size);
		if (bp->b_bufsize == fs->e2fs_bsize)
			bp->b_flags |= B_CLUSTEROK;
		if (flags & IO_SYNC)
			bwrite(bp);
		else if (DOINGASYNC(ovp))
			bdwrite(bp);
		else
			bawrite(bp);
	}
	/*
	 * Calculate index into inode's block list of
	 * last direct and indirect blocks (if any)
	 * which we want to keep.  Lastblock is -1 when
	 * the file is truncated to 0.
	 */
	lastblock = lblkno(fs, length + fs->e2fs_bsize - 1) - 1;
	lastiblock[SINGLE] = lastblock - NDADDR;
	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
	nblocks = btodb(fs->e2fs_bsize);
	/*
	 * Update file and block pointers on disk before we start freeing
	 * blocks.  If we crash before free'ing blocks below, the blocks
	 * will be returned to the free list.  lastiblock values are also
	 * normalized to -1 for calls to ext2_indirtrunc below.
	 */
	for (level = TRIPLE; level >= SINGLE; level--) {
		oldblks[NDADDR + level] = oip->i_ib[level];
		if (lastiblock[level] < 0) {
			oip->i_ib[level] = 0;
			lastiblock[level] = -1;
		}
	}
	for (i = 0; i < NDADDR; i++) {
		oldblks[i] = oip->i_db[i];
		if (i > lastblock)
			oip->i_db[i] = 0;
	}
	oip->i_flag |= IN_CHANGE | IN_UPDATE;
	allerror = ext2_update(ovp, !DOINGASYNC(ovp));

	/*
	 * Having written the new inode to disk, save its new configuration
	 * and put back the old block pointers long enough to process them.
	 * Note that we save the new block configuration so we can check it
	 * when we are done.
	 */
	for (i = 0; i < NDADDR; i++) {
		newblks[i] = oip->i_db[i];
		oip->i_db[i] = oldblks[i];
	}
	for (i = 0; i < NIADDR; i++) {
		newblks[NDADDR + i] = oip->i_ib[i];
		oip->i_ib[i] = oldblks[NDADDR + i];
	}
	oip->i_size = osize;
	error = vtruncbuf(ovp, cred, length, (int)fs->e2fs_bsize);
	if (error && (allerror == 0))
		allerror = error;
	vnode_pager_setsize(ovp, length);

	/*
	 * Indirect blocks first.
	 */
	indir_lbn[SINGLE] = -NDADDR;
	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
	for (level = TRIPLE; level >= SINGLE; level--) {
		bn = oip->i_ib[level];
		if (bn != 0) {
			error = ext2_indirtrunc(oip, indir_lbn[level],
			    fsbtodb(fs, bn), lastiblock[level], level, &count);
			if (error)
				allerror = error;
			blocksreleased += count;
			if (lastiblock[level] < 0) {
				oip->i_ib[level] = 0;
				ext2_blkfree(oip, bn, fs->e2fs_fsize);
				blocksreleased += nblocks;
			}
		}
		if (lastiblock[level] >= 0)
			goto done;
	}

	/*
	 * All whole direct blocks or frags.
	 */
	for (i = NDADDR - 1; i > lastblock; i--) {
		long bsize;

		bn = oip->i_db[i];
		if (bn == 0)
			continue;
		oip->i_db[i] = 0;
		bsize = blksize(fs, oip, i);
		ext2_blkfree(oip, bn, bsize);
		blocksreleased += btodb(bsize);
	}
	if (lastblock < 0)
		goto done;

	/*
	 * Finally, look for a change in size of the
	 * last direct block; release any frags.
	 */
	bn = oip->i_db[lastblock];
	if (bn != 0) {
		long oldspace, newspace;

		/*
		 * Calculate amount of space we're giving
		 * back as old block size minus new block size.
		 */
		oldspace = blksize(fs, oip, lastblock);
		oip->i_size = length;
		newspace = blksize(fs, oip, lastblock);
		if (newspace == 0)
			panic("ext2_truncate: newspace");
		if (oldspace - newspace > 0) {
			/*
			 * Block number of space to be free'd is
			 * the old block # plus the number of frags
			 * required for the storage we're keeping.
			 */
			bn += numfrags(fs, newspace);
			ext2_blkfree(oip, bn, oldspace - newspace);
			blocksreleased += btodb(oldspace - newspace);
		}
	}
done:
#ifdef INVARIANTS
	for (level = SINGLE; level <= TRIPLE; level++)
		if (newblks[NDADDR + level] != oip->i_ib[level])
			panic("itrunc1");
	for (i = 0; i < NDADDR; i++)
		if (newblks[i] != oip->i_db[i])
			panic("itrunc2");
	BO_LOCK(bo);
	if (length == 0 && (bo->bo_dirty.bv_cnt != 0 ||
	    bo->bo_clean.bv_cnt != 0))
		panic("itrunc3");
	BO_UNLOCK(bo);
#endif /* INVARIANTS */
	/*
	 * Put back the real size.
	 */
	oip->i_size = length;
	if (oip->i_blocks >= blocksreleased)
		oip->i_blocks -= blocksreleased;
	else				/* sanity */
		oip->i_blocks = 0;
	oip->i_flag |= IN_CHANGE;
	vnode_pager_setsize(ovp, length);
	return (allerror);
}
示例#11
0
int
ext2_reallocblks(struct vop_reallocblks_args *ap)
{
    struct m_ext2fs *fs;
    struct inode *ip;
    struct vnode *vp;
    struct buf *sbp, *ebp;
    uint32_t *bap, *sbap, *ebap = 0;
    struct ext2mount *ump;
    struct cluster_save *buflist;
    struct indir start_ap[NIADDR + 1], end_ap[NIADDR + 1], *idp;
    e2fs_lbn_t start_lbn, end_lbn;
    int soff;
    e2fs_daddr_t newblk, blkno;
    int i, len, start_lvl, end_lvl, pref, ssize;

    if (doreallocblks == 0)
        return (ENOSPC);

    vp = ap->a_vp;
    ip = VTOI(vp);
    fs = ip->i_e2fs;
    ump = ip->i_ump;

    if (fs->e2fs_contigsumsize <= 0)
        return (ENOSPC);

    buflist = ap->a_buflist;
    len = buflist->bs_nchildren;
    start_lbn = buflist->bs_children[0]->b_lblkno;
    end_lbn = start_lbn + len - 1;
#ifdef INVARIANTS
    for (i = 1; i < len; i++)
        if (buflist->bs_children[i]->b_lblkno != start_lbn + i)
            panic("ext2_reallocblks: non-cluster");
#endif
    /*
     * If the cluster crosses the boundary for the first indirect
     * block, leave space for the indirect block. Indirect blocks
     * are initially laid out in a position after the last direct
     * block. Block reallocation would usually destroy locality by
     * moving the indirect block out of the way to make room for
     * data blocks if we didn't compensate here. We should also do
     * this for other indirect block boundaries, but it is only
     * important for the first one.
     */
    if (start_lbn < NDADDR && end_lbn >= NDADDR)
        return (ENOSPC);
    /*
     * If the latest allocation is in a new cylinder group, assume that
     * the filesystem has decided to move and do not force it back to
     * the previous cylinder group.
     */
    if (dtog(fs, dbtofsb(fs, buflist->bs_children[0]->b_blkno)) !=
            dtog(fs, dbtofsb(fs, buflist->bs_children[len - 1]->b_blkno)))
        return (ENOSPC);
    if (ext2_getlbns(vp, start_lbn, start_ap, &start_lvl) ||
            ext2_getlbns(vp, end_lbn, end_ap, &end_lvl))
        return (ENOSPC);
    /*
     * Get the starting offset and block map for the first block.
     */
    if (start_lvl == 0) {
        sbap = &ip->i_db[0];
        soff = start_lbn;
    } else {
        idp = &start_ap[start_lvl - 1];
        if (bread(vp, idp->in_lbn, (int)fs->e2fs_bsize, NOCRED, &sbp)) {
            brelse(sbp);
            return (ENOSPC);
        }
        sbap = (u_int *)sbp->b_data;
        soff = idp->in_off;
    }
    /*
     * If the block range spans two block maps, get the second map.
     */
    if (end_lvl == 0 || (idp = &end_ap[end_lvl - 1])->in_off + 1 >= len) {
        ssize = len;
    } else {
#ifdef INVARIANTS
        if (start_ap[start_lvl-1].in_lbn == idp->in_lbn)
            panic("ext2_reallocblks: start == end");
#endif
        ssize = len - (idp->in_off + 1);
        if (bread(vp, idp->in_lbn, (int)fs->e2fs_bsize, NOCRED, &ebp))
            goto fail;
        ebap = (u_int *)ebp->b_data;
    }
    /*
     * Find the preferred location for the cluster.
     */
    EXT2_LOCK(ump);
    pref = ext2_blkpref(ip, start_lbn, soff, sbap, 0);
    /*
     * Search the block map looking for an allocation of the desired size.
     */
    if ((newblk = (e2fs_daddr_t)ext2_hashalloc(ip, dtog(fs, pref), pref,
                  len, ext2_clusteralloc)) == 0) {
        EXT2_UNLOCK(ump);
        goto fail;
    }
    /*
     * We have found a new contiguous block.
     *
     * First we have to replace the old block pointers with the new
     * block pointers in the inode and indirect blocks associated
     * with the file.
     */
#ifdef DEBUG
    printf("realloc: ino %d, lbns %jd-%jd\n\told:", ip->i_number,
           (intmax_t)start_lbn, (intmax_t)end_lbn);
#endif /* DEBUG */
    blkno = newblk;
    for (bap = &sbap[soff], i = 0; i < len; i++, blkno += fs->e2fs_fpb) {
        if (i == ssize) {
            bap = ebap;
            soff = -i;
        }
#ifdef INVARIANTS
        if (buflist->bs_children[i]->b_blkno != fsbtodb(fs, *bap))
            panic("ext2_reallocblks: alloc mismatch");
#endif
#ifdef DEBUG
        printf(" %d,", *bap);
#endif /* DEBUG */
        *bap++ = blkno;
    }
    /*
     * Next we must write out the modified inode and indirect blocks.
     * For strict correctness, the writes should be synchronous since
     * the old block values may have been written to disk. In practise
     * they are almost never written, but if we are concerned about
     * strict correctness, the `doasyncfree' flag should be set to zero.
     *
     * The test on `doasyncfree' should be changed to test a flag
     * that shows whether the associated buffers and inodes have
     * been written. The flag should be set when the cluster is
     * started and cleared whenever the buffer or inode is flushed.
     * We can then check below to see if it is set, and do the
     * synchronous write only when it has been cleared.
     */
    if (sbap != &ip->i_db[0]) {
        if (doasyncfree)
            bdwrite(sbp);
        else
            bwrite(sbp);
    } else {
        ip->i_flag |= IN_CHANGE | IN_UPDATE;
        if (!doasyncfree)
            ext2_update(vp, 1);
    }
    if (ssize < len) {
        if (doasyncfree)
            bdwrite(ebp);
        else
            bwrite(ebp);
    }
    /*
     * Last, free the old blocks and assign the new blocks to the buffers.
     */
#ifdef DEBUG
    printf("\n\tnew:");
#endif /* DEBUG */
    for (blkno = newblk, i = 0; i < len; i++, blkno += fs->e2fs_fpb) {
        ext2_blkfree(ip, dbtofsb(fs, buflist->bs_children[i]->b_blkno),
                     fs->e2fs_bsize);
        buflist->bs_children[i]->b_blkno = fsbtodb(fs, blkno);
#ifdef DEBUG
        printf(" %d,", blkno);
#endif /* DEBUG */
    }
#ifdef DEBUG
    printf("\n");
#endif /* DEBUG */
    return (0);

fail:
    if (ssize < len)
        brelse(ebp);
    if (sbap != &ip->i_db[0])
        brelse(sbp);
    return (ENOSPC);
}