Re: kern/60456: FFS_NO_SNAPSHOT option is not entirely effective

[Taylor R Campbell <riastradh%NetBSD.org@localhost>]

> Date: Sat, 18 Jul 2026 14:53:08 -0700
> From: Jason Thorpe <thorpej%me.com@localhost>
> 
> > On Jul 18, 2026, at 12:51â?¯PM, Taylor R Campbell <riastradh%NetBSD.org@localhost> wrote:
> > 
> > Perhaps we should have an option that elides all of the file system
> > snapshot code, but adds a small check so that if you try to mount a
> > file system with any snapshots, it refuses to mount read/write -- only
> > allows mounting file systems with snapshots read-only, so that you
> > won't inadvertently corrupt the snapshots.
> 
> Indeed, vfs_trans.c also contributes a non-trivial bit of .text on
> smol machines.

vfs_trans.c is for a lot more than just snapshots -- e.g., it is
needed for unmounting or changing mount options, or for revoking
vnodes either with revoke(2) (closing ttys) or detaching devices.
Perhaps you can #ifdef out the cow pastures of vfs_trans.c but not the
other parts.