[PATCH] olpc.fth - grow the root filesystem partition on boot

[James Cameron]

On Wed, Mar 14, 2012 at 07:02:51PM -0400, John Watlington wrote:
> 
> On Mar 14, 2012, at 6:04 PM, James Cameron wrote:
> 
> > On Wed, Mar 14, 2012 at 08:37:23AM -0600, Daniel Drake wrote:
> >> On Wed, Mar 14, 2012 at 7:06 AM, Richard Smith <richard at laptop.org> wrote:
> >>> On Wed, Mar 14, 2012 at 1:35 AM, James Cameron <quozl at laptop.org> wrote:
> >>>> Grows the second partition so that it takes up all remaining space on
> >>>> the eMMC or microSD card. ?Fix for #11690. ?Part of #10040.
> >>>> 
> >>>> Costs 120ms. ?(Use of a flag file costs 130ms).
> >>>> 
> >>> 
> >>> I don't think its necessary to do this check every boot. I propose you
> >>> move it to after fs-update has installed an image.
> >> 
> >> Also, olpc.fth isn't executed in the secure boot path, so it does need
> >> to be put somewhere else. I like Richard's suggestion.
> > 
> > This would break fs-verify, and is therefore unacceptable.
> 
> Is this really a concern ?   It doesn't break fs-verify if one is using the correct
> image for the storage device in question.   Or are we tweaking the filesystem
> to get the extra few MB with some cards ?

With #11690 and #10040 fixed, we would only need to create one image for
the smallest storage device shipped.  Every image would then be the
correct image.

Yes, this method can be used to "free up" the unused space between the
size of the smallest image and the size of the smallest storage device
shipped, but that is a side-effect.

fs-verify is used after fs-update in factory to ensure that the
fs-update was successful.

We might instead place it in the olpc.fth path for insecure boot, and in
the fs-update path for secure install.

Or we might add it to the tail of fs-update, and add an
fs-update-no-resize for the factory to use, with an fs-resize for them
to use after fs-verify.

-- 
James Cameron
http://quozl.linux.org.au/