Re: [DistroKit] [PATCH 5/6] images: remove qemu size hack

[Roland Hieber <rhi@pengutronix.de>]

On Wed, Oct 11, 2023 at 11:45:37AM +0200, Roland Hieber wrote:
> On Wed, Oct 11, 2023 at 11:40:40AM +0200, Roland Hieber wrote:
> > On Wed, Oct 11, 2023 at 08:51:15AM +0200, Michael Olbrich wrote:
> > > On Tue, Oct 10, 2023 at 09:16:30PM +0200, Roland Hieber wrote:
> > > > genimage knows about the 'size' option for images to fill the image to a
> > > > certain size, and since genimage v14 it supports the 'fill' option to
> > > > write all zeroes at the end of the image and not cut them off to
> > > > optimise the image size. Use this to blow up the images that are used
> > > > with qemu to the next power of two so qemu can work with them, and
> > > > remove our invisible-partition-at-the-end hack.
> > > > 
> > > > On MIPS, we also need to decrease the size of the last partition so that
> > > > it still fits inside the specified image size, because the first MiB
> > > > (when using 1 MiB alignment) is occupied by the partition table, so the
> > > > first partition only starts at offset 1 MiB.
> > > > 
> > > > Signed-off-by: Roland Hieber <rhi@pengutronix.de>
> > > > ---
> > > >  .../platform-mips/config/images/ar9331.config    | 16 ++++------------
> > > >  configs/platform-mips/config/images/malta.config | 16 ++++------------
> > > >  .../platform-mipsel/config/images/malta.config   | 16 ++++------------
> > > >  .../config/images/vexpress-nor.config            | 10 +++-------
> > > >  .../platform-v7a/config/images/vexpress.config   | 15 +++------------
> > > >  .../config/images/vexpress-nor.config            | 10 +++-------
> > > >  .../config/images/vexpress.config                | 15 +++------------
> > > >  7 files changed, 24 insertions(+), 74 deletions(-)
> > > > 
> > > > diff --git a/configs/platform-mips/config/images/ar9331.config b/configs/platform-mips/config/images/ar9331.config
> > > > index 07125bea4c88..8012cf0f839d 100644
> > > > --- a/configs/platform-mips/config/images/ar9331.config
> > > > +++ b/configs/platform-mips/config/images/ar9331.config
> > > > @@ -1,7 +1,10 @@
> > > >  image @IMAGE@ {
> > > > +	/* Note: qemu will complain if the SD card size is not a power of two */
> > > > +	size = 1G
> > > >  	hdimage {
> > > >  		align = 1M
> > > >  		disk-signature = 0x74823abf
> > > > +		fill = true
> > > >  	}
> > > >  	partition root-A {
> > > >  		image = root.ext2
> > > > @@ -10,18 +13,7 @@ image @IMAGE@ {
> > > >  	}
> > > >  	partition data {
> > > >  		partition-type = 0x83
> > > > -		size = 512M
> > > > -	}
> > > > -	/* genimage does not write zeros at the end of an image to save space,
> > > > -	 * but the kernel in qemu will complain if the image file is smaller
> > > > -	 * than the partition sizes. work around this by adding an empty
> > > > -	 * partition at the end.
> > > > -	 */
> > > > -	partition end {
> > > > -		image = /dev/null
> > > > -		size = 1M
> > > > -		offset = 1025M
> > > > -		in-partition-table = false
> > > > +		size = 511M
> > > 
> > > The last partition can have a 'fill = true' property if the image size is
> > > explicitly specified. That's better than calculating it manually.
> > 
> > Apparently not…?
> 
> Ah. Because it was only added in genimage commit e123753a4f03, which is
> not released yet, so PTXdist can't have it yet.
> 
> https://github.com/pengutronix/genimage/commit/e123753a4f03415dad7c

Ah, but there is the option 'autoresize', which works as expected in
hdimage sections. Will use that for v2.

 - Roland

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