Support for btrfs in pv-grub

Support for btrfs in pv-grub

[Charles Arnold]

Code to support btrfs in pv-grub was added almost two years ago (c/s 25154).
Building the code doesn't seem to be enabled in stubdom/grub/Makefile.
Was this functionality ever intended to work? 
Does anyone know the status of this code?

Re: Support for btrfs in pv-grub

[Ian Campbell]

On Wed, 2014-02-26 at 15:59 -0700, Charles Arnold wrote:
> Code to support btrfs in pv-grub was added almost two years ago (c/s 25154).

Ccing the author.

> Building the code doesn't seem to be enabled in stubdom/grub/Makefile.
> Was this functionality ever intended to work?

One would like to assume so!

> Does anyone know the status of this code?

Matt?

Looks like Makefile.am was patched but not Makefile.in, and I don't
think we run automake as part of the stubdom build process.

Ian.

Re: Support for btrfs in pv-grub

[Matt Wilson]

On Fri, Feb 28, 2014 at 02:42:28AM +0000, Ian Campbell wrote:
> On Wed, 2014-02-26 at 15:59 -0700, Charles Arnold wrote:
> > Code to support btrfs in pv-grub was added almost two years ago (c/s 25154).
> 
> Ccing the author.
> 
> > Building the code doesn't seem to be enabled in stubdom/grub/Makefile.
> > Was this functionality ever intended to work?
> 
> One would like to assume so!
> 
> > Does anyone know the status of this code?
> 
> Matt?
> 
> Looks like Makefile.am was patched but not Makefile.in, and I don't
> think we run automake as part of the stubdom build process.

True, but we also don't use the Makefiles in grub-upstream to build
GRUB. We use xen/stubdom/grub/Makefile, which also isn't patched to
build the btrfs code.

Unfortunately when I added it grub/Makefile, it doesn't build on a
modern compiler.

Do you think we should revert the patch that adds btrfs support?

--msw

Re: Support for btrfs in pv-grub

[Charles Arnold]

>>> On 2/27/2014 at 08:30 PM, Matt Wilson <msw@linux.com> wrote: 
> On Fri, Feb 28, 2014 at 02:42:28AM +0000, Ian Campbell wrote:
>> On Wed, 2014-02-26 at 15:59 -0700, Charles Arnold wrote:
>> > Code to support btrfs in pv-grub was added almost two years ago (c/s 25154).
>> 
>> Ccing the author.
>> 
>> > Building the code doesn't seem to be enabled in stubdom/grub/Makefile.
>> > Was this functionality ever intended to work?
>> 
>> One would like to assume so!
>> 
>> > Does anyone know the status of this code?
>> 
>> Matt?
>> 
>> Looks like Makefile.am was patched but not Makefile.in, and I don't
>> think we run automake as part of the stubdom build process.
> 
> True, but we also don't use the Makefiles in grub-upstream to build
> GRUB. We use xen/stubdom/grub/Makefile, which also isn't patched to
> build the btrfs code.
> 
> Unfortunately when I added it grub/Makefile, it doesn't build on a
> modern compiler.
> 
> Do you think we should revert the patch that adds btrfs support?
> 
> --msw

Another option would be to fix the compiler errors and get it working :)
The compiler has problems with the cassert define and to many args in
the call to next_partition in the 61btrfs.diff patch.  These issues may be
worked around but given that the code has never actually been used there
may be runtime problems as well.  Is there someone familiar enough with
btrfs on the list to work through these issues?

- Charles

Re: Support for btrfs in pv-grub

[Ian Campbell]

On Thu, 2014-02-27 at 19:30 -0800, Matt Wilson wrote:
> On Fri, Feb 28, 2014 at 02:42:28AM +0000, Ian Campbell wrote:
> > On Wed, 2014-02-26 at 15:59 -0700, Charles Arnold wrote:
> > > Code to support btrfs in pv-grub was added almost two years ago (c/s 25154).
> > 
> > Ccing the author.
> > 
> > > Building the code doesn't seem to be enabled in stubdom/grub/Makefile.
> > > Was this functionality ever intended to work?
> > 
> > One would like to assume so!
> > 
> > > Does anyone know the status of this code?
> > 
> > Matt?
> > 
> > Looks like Makefile.am was patched but not Makefile.in, and I don't
> > think we run automake as part of the stubdom build process.
> 
> True, but we also don't use the Makefiles in grub-upstream to build
> GRUB. We use xen/stubdom/grub/Makefile, which also isn't patched to
> build the btrfs code.

So this code was untested when it was submitted and you aren't using it
today?

> Unfortunately when I added it grub/Makefile, it doesn't build on a
> modern compiler.
> 
> Do you think we should revert the patch that adds btrfs support?

Unless someone is going to fix it up up as Charles suggests then it
seems misleading to keep it in the code base.

Ian.