Implemented filesystem clean bit via:

machdep.c:
	Changed printf's a little and call vfs_unmountall() if the sync was
	successful.

cd9660_vfsops.c, ffs_vfsops.c, nfs_vfsops.c, lfs_vfsops.c:
	Allow dismount of root FS. It is now disallowed at a higher level.

vfs_conf.c:
	Removed unused rootfs global.

vfs_subr.c:
	Added new routines vfs_unmountall and vfs_unmountroot. Filesystems
	are now dismounted if the machine is properly rebooted.

ffs_vfsops.c:
	Toggle clean bit at the appropriate places. Print warning if an
	unclean FS is mounted.

ffs_vfsops.c, lfs_vfsops.c:
	Fix bug in selecting proper flags for VOP_CLOSE().

vfs_syscalls.c:
	Disallow dismounting root FS via umount syscall.

1 files changed, 65 insertions, 1 deletions

diff --git a/sys/kern/vfs_export.c b/sys/kern/vfs_export.c
index d088b28bf317..e26b0303f20b 100644
--- a/sys/kern/vfs_export.c
+++ b/sys/kern/vfs_export.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_subr.c	8.13 (Berkeley) 4/18/94
- * $Id: vfs_subr.c,v 1.3 1994/08/02 07:43:27 davidg Exp $
+ * $Id: vfs_subr.c,v 1.4 1994/08/18 22:35:09 wollman Exp $
  */
 
 /*
@@ -169,6 +169,70 @@ vfs_unbusy(mp)
 	}
 }
 
+void
+vfs_unmountroot(rootfs)
+	struct mount *rootfs;
+{
+	struct	mount *mp = rootfs;
+	int	error;
+
+	if (vfs_busy(mp)) {
+		printf("failed to unmount root\n");
+		return;
+	}
+
+	mp->mnt_flag |= MNT_UNMOUNT;
+	if (error = vfs_lock(mp)) {
+		printf("lock of root filesystem failed (%d)\n", error);
+		return;
+	}
+
+	vnode_pager_umount(mp);	/* release cached vnodes */
+	cache_purgevfs(mp);	/* remove cache entries for this file sys */
+
+	if (error = VFS_SYNC(mp, MNT_WAIT, initproc->p_ucred, initproc))
+		printf("sync of root filesystem failed (%d)\n", error);
+
+	if (error = VFS_UNMOUNT(mp, MNT_FORCE, initproc))
+		printf("unmount of root filesystem failed (%d)\n", error);
+
+	mp->mnt_flag &= ~MNT_UNMOUNT;
+	vfs_unbusy(mp);
+}
+
+/*
+ * Unmount all filesystems.  Should only be called by halt().
+ */
+void
+vfs_unmountall()
+{
+	struct mount *mp, *mp_next, *rootfs = NULL;
+	int error;
+
+	/* unmount all but rootfs */
+	for (mp = mountlist.tqh_first; mp != NULL; mp = mp_next) {
+		mp_next = mp->mnt_list.tqe_next;
+
+		if (mp->mnt_flag & MNT_ROOTFS) {
+			rootfs = mp;
+			continue;
+		}
+
+		error = dounmount(mp, MNT_FORCE, initproc);
+		if (error) {
+			printf("unmount of %s failed (%d)\n",
+			    mp->mnt_stat.f_mntonname, error);
+		}
+	}
+
+	/* and finally... */
+	if (rootfs) {
+		vfs_unmountroot(rootfs);
+	} else {
+		printf("no root filesystem\n");
+	}
+}
+
 /*
  * Lookup a mount point by filesystem identifier.
  */