Index: sys/fs/tmpfs/tmpfs_vfsops.c
===================================================================
--- sys/fs/tmpfs/tmpfs_vfsops.c
+++ sys/fs/tmpfs/tmpfs_vfsops.c
@@ -438,4 +438,4 @@
 	.vfs_fhtovp =			tmpfs_fhtovp,
 	.vfs_sync =			tmpfs_sync,
 };
-VFS_SET(tmpfs_vfsops, tmpfs, VFCF_JAIL);
+VFS_SET(tmpfs_vfsops, tmpfs, VFCF_JAIL | VFCF_SUSPEND);
Index: sys/kern/vfs_vnops.c
===================================================================
--- sys/kern/vfs_vnops.c
+++ sys/kern/vfs_vnops.c
@@ -1572,6 +1572,25 @@
 	return (error);
 }
 
+static bool
+vn_has_suspend_mp(struct mount *mp)
+{
+
+	return ((mp->mnt_vfc->vfc_flags & VFCF_SUSPEND) != 0);
+}
+
+static bool
+vn_has_suspend(struct vnode *vp, struct mount **mpp)
+{
+
+	if (vp != NULL)
+		*mpp = vp->v_mount;
+	if (*mpp == NULL)
+		return (false);
+
+	return (vn_has_suspend_mp(*mpp));
+}
+
 /*
  * Preparing to start a filesystem write operation. If the operation is
  * permitted, then we bump the count of operations in progress and
@@ -1621,6 +1640,9 @@
 	struct mount *mp;
 	int error;
 
+	if (!vn_has_suspend(vp, mpp))
+		return (0);
+
 	error = 0;
 	/*
 	 * If a vnode is provided, get and return the mount point that
@@ -1683,6 +1705,7 @@
 	if ((mp = *mpp) == NULL)
 		return (0);
 
+	MPASS(vn_has_suspend_mp(mp));
 	/*
 	 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
 	 * a vfs_ref().
@@ -1724,7 +1747,7 @@
 vn_finished_write(mp)
 	struct mount *mp;
 {
-	if (mp == NULL)
+	if (mp == NULL || !vn_has_suspend_mp(mp))
 		return;
 	MNT_ILOCK(mp);
 	MNT_REL(mp);
@@ -1749,6 +1772,7 @@
 {
 	if (mp == NULL)
 		return;
+	MPASS(vn_has_suspend_mp(mp));
 	MNT_ILOCK(mp);
 	MNT_REL(mp);
 	mp->mnt_secondary_writes--;
@@ -1770,6 +1794,8 @@
 {
 	int error;
 
+	MPASS(vn_has_suspend_mp(mp));
+
 	MNT_ILOCK(mp);
 	if (mp->mnt_susp_owner == curthread) {
 		MNT_IUNLOCK(mp);
@@ -1811,6 +1837,8 @@
 vfs_write_resume(struct mount *mp, int flags)
 {
 
+	MPASS(vn_has_suspend_mp(mp));
+
 	MNT_ILOCK(mp);
 	if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
 		KASSERT(mp->mnt_susp_owner == curthread, ("mnt_susp_owner"));
@@ -1844,6 +1872,7 @@
 {
 	int error;
 
+	MPASS(vn_has_suspend_mp(mp));
 	KASSERT((curthread->td_pflags & TDP_IGNSUSP) == 0,
 	    ("vfs_write_suspend_umnt: recursed"));
 
Index: sys/sys/mount.h
===================================================================
--- sys/sys/mount.h
+++ sys/sys/mount.h
@@ -511,6 +511,7 @@
 #define	VFCF_JAIL	0x00400000	/* can be mounted from within a jail */
 #define	VFCF_DELEGADMIN	0x00800000	/* supports delegated administration */
 #define	VFCF_SBDRY	0x01000000	/* defer stop requests */
+#define	VFCF_SUSPEND	0x02000000	/* rely on VFS to provide suspension */
 
 typedef uint32_t fsctlop_t;
 
Index: sys/ufs/ffs/ffs_vfsops.c
===================================================================
--- sys/ufs/ffs/ffs_vfsops.c
+++ sys/ufs/ffs/ffs_vfsops.c
@@ -109,7 +109,7 @@
 	.vfs_susp_clean =	process_deferred_inactive,
 };
 
-VFS_SET(ufs_vfsops, ufs, 0);
+VFS_SET(ufs_vfsops, ufs, VFCF_SUSPEND);
 MODULE_VERSION(ufs, 1);
 
 static b_strategy_t ffs_geom_strategy;