gvinum: add deprecation notice

Vinum is a Logical Volume Manager that was introduced in FreeBSD 3.0,
and for FreeBSD 5 was ported to geom(4) as gvinum. gvinum has had no
specific development at least as far back as 2010, and has a number of
known bugs which are unlikely to be resolved.

Add a deprecation notice to raise awareness but state that vinum "may
not be" available in FreeBSD 14.  Either it will be removed and the
notice will be updated to "is not" available, or someone will step up
to fix issues and maintain it and we will remove the notice.

Reviewed by:	imp (earlier version)
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D29424

(cherry picked from commit b218441ac074d9cb9417e284980bf87f79a89585)

1 files changed, 17 insertions, 1 deletions

diff --git a/sbin/gvinum/gvinum.8 b/sbin/gvinum/gvinum.8
index 950a0188946f..a8135e9bf4a2 100644
--- a/sbin/gvinum/gvinum.8
+++ b/sbin/gvinum/gvinum.8
@@ -28,12 +28,28 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd May 6, 2014
+.Dd March 28, 2021
 .Dt GVINUM 8
 .Os
 .Sh NAME
 .Nm gvinum
 .Nd Logical Volume Manager control program
+.Sh DEPRECATION NOTICE
+.Nm
+and associated
+.Xr geom 4
+kernel support is deprecated, and may not be available in
+.Fx 14.0
+and later.
+Users are advised to migrate to
+.Xr gconcat 8 ,
+.Xr gmirror 8 ,
+.Xr gstripe 8 ,
+.Xr graid 8 ,
+or
+.Xr ZFS 8 .
+More information is available at
+.Pa https://wiki.freebsd.org/DeprecationPlan/gvinum .
 .Sh SYNOPSIS
 .Nm
 .Op Ar command