Index: share/man/man9/Makefile
===================================================================
--- share/man/man9/Makefile
+++ share/man/man9/Makefile
@@ -2233,6 +2233,7 @@
 MLINKS+=VOP_CREATE.9 VOP_MKDIR.9 \
 	VOP_CREATE.9 VOP_MKNOD.9 \
 	VOP_CREATE.9 VOP_SYMLINK.9
+MLINKS+=VOP_FSYNC.9 VOP_FDATASYNC.9
 MLINKS+=VOP_GETPAGES.9 VOP_PUTPAGES.9
 MLINKS+=VOP_INACTIVE.9 VOP_RECLAIM.9
 MLINKS+=VOP_LOCK.9 vn_lock.9 \
Index: share/man/man9/VOP_FSYNC.9
===================================================================
--- share/man/man9/VOP_FSYNC.9
+++ share/man/man9/VOP_FSYNC.9
@@ -28,19 +28,23 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 24, 1996
+.Dd March 22, 2019
 .Dt VOP_FSYNC 9
 .Os
 .Sh NAME
+.Nm VOP_FDATASYNC ,
 .Nm VOP_FSYNC
 .Nd flush file system buffers for a file
 .Sh SYNOPSIS
 .In sys/param.h
 .In sys/vnode.h
 .Ft int
+.Fn VOP_FDATASYNC "struct vnode *vp" "struct thread *td"
+.Ft int
 .Fn VOP_FSYNC "struct vnode *vp" "int waitfor" "struct thread *td"
 .Sh DESCRIPTION
-This call flushes any dirty file system buffers for the file.
+.Fn VOP_FSYNC
+flushes any dirty file system buffers for the file.
 It is used to implement the
 .Xr sync 2
 and
@@ -65,6 +69,21 @@
 .It Fa td
 The calling thread.
 .El
+.Pp
+.Fn VOP_FDATASYNC
+is similar, but it does not require that all of the file's metadata be flushed.
+It only requires that the file's data be recoverable after a crash.
+It has the same arguments as
+.Fn VOP_FSYNC ,
+except for
+.Fa waitfor .
+Instead, 
+.Fn VOP_FDATASYNC
+should always wait for I/O to complete, as if called with
+.Dv MNT_WAIT .
+.Fn VOP_FDATASYNC
+is used to implement
+.Xr fdatasync 2 .
 .Sh LOCKS
 The file should be locked on entry.
 .Sh RETURN VALUES