Re: ubifs version 1 compatibility

[Hamish Moffatt <hamish@cloud.net.au>]

On Thu, Mar 26, 2009 at 11:50:23AM +0200, Artem Bityutskiy wrote:
> On Thu, 2009-03-26 at 18:44 +1100, Hamish Moffatt wrote:
> makes it very difficult to turn old image into new one. This will
> basically mean we need:
> 
> 1. extract files from the old image
> 2. feed them to mkfs.ubifs.
> 
> > Maybe before upgrade we could run mkfs.ubifs using the contents of the
> > existing volume to create the new format, unmount it and ubiupdatevol it..
> 
> The easiest way to do this is to boot the old kernel,
> e.g. in vmware, extract the files using the nandsim technique:
> http://www.linux-mtd.infradead.org/faq/ubifs.html#L_ubifs_nandsim
> 
> then feed them to mkfs.ubifs.

Well I have these files on embedded devices out in the real world. The
volume is storing user data, so I need to do this change in-place.

> But yes, a user-space utility to extract files from an image would be
> of course nicer, but again it is something which is not easy to do.

OK I will investigate having the system build a new file system with
a new mkfs.ubifs while running the old kernel.. Alternatively I may be
able to stash the data somewhere else and copy it back when the new
kernel first boots.. I probably have some space in NOR for a small JFFS2
volume. Or I'll tar directly to an mtdblock device or something :)


thanks
Hamish
-- 
Hamish Moffatt VK3SB <hamish@debian.org> <hamish@cloud.net.au>