svn commit: r293776 - stable/10/usr.sbin/fstyp

[Slawa Olhovchenkov]

On Wed, Jan 13, 2016 at 08:35:14AM -0800, Matthew Ahrens wrote:

> On Wed, Jan 13, 2016 at 8:32 AM, Warner Losh <imp at bsdimp.com> wrote:
> 
> >
> > > On Jan 13, 2016, at 9:26 AM, Allan Jude <allanjude at FreeBSD.org> wrote:
> > >
> > > On 2016-01-13 08:18, Slawa Olhovchenkov wrote:
> > >> On Tue, Jan 12, 2016 at 04:38:09PM +0000, Allan Jude wrote:
> > >>
> > >>> Author: allanjude
> > >>> Date: Tue Jan 12 16:38:09 2016
> > >>> New Revision: 293776
> > >>> URL: https://svnweb.freebsd.org/changeset/base/293776
> > >>>
> > >>> Log:
> > >>>  MFC: r284589
> > >>>    Add the ability to detect ZFS and GELI encrypted file systems to
> > fstyp(8)
> > >>>
> > >>>  MFC: r284644
> > >>>    Fix GCC Warnings
> > >>>
> > >>>  MFC: r284728
> > >>>    Only build ZFS support in absense of WITHOUT_ZFS
> > >>
> > >> What purpose for switch off ZFS support in case WITHOUT_ZFS?
> > >>
> > >
> > > If the user builds FreeBSD WITHOUT_CDDL or WITHOUT_ZFS, then they are
> > > requesting that we not build the ZFS code, so building it anyway would
> > > be against their wishes. The most likely reason they would request this
> > > is for license reasons.

And what main reason in this case: license or memory consumption?

> > For x86, that may be true. For arm and mips platforms, ZFS is too much of a
> > memory pig-dog to run on much of the kit we run on in that space. Turning
> > it
> > off is part of removing the type 2 muda from the system.

How many additional memory footpint need for support ZFS detecting?

> > In any event, the double negative is true. Don’t build ZFS when its
> > absence has
> > been requested with WITHOUT_ZFS is correct.
> >
> 
> Some of the confusion may be because this is not building ZFS -
> just support for detecting ZFS pools in fstyp.  Which would be reasonable
> to do even if you are not building support for ZFS.

Yes, for diagnostic purpose (interactive and in srcipts).
Also, ZFS may be in FUSE or may be exported by iSCSI (and ZFS
detecting need for selecting raw disk for exporting).

> However, the fstyp ZFS code relies on libzfs and libnvpair which are CDDL
> licensed.  So if you did not build ZFS (or CDDL), the fstyp code could not
> work.

May be better relies on WITHOUT_CDDL? If main purpose is license reasons?