Before UBI got into mainline, there was a slight flash format
change - we did not have sequence number support, then added it.
We have carried full support of those ancient images till this
moment. Now the support is removed, well, not fully removed.
Now UBI will support only _clean_ old images, which were cleanly
detached last time (just before kernel upgrade). This is most
likely the case.
But we will not support unclean ancient images. Surprisingly,
this allows us to remove a big chunk of legacy code.
And the same should be true for downgrading: clean images should
downgrade fine, but unclean ones will not.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Hch asked not to use "unit" for sub-systems, let it be so.
Also some other commentaries modifications.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The new trend in linux is not to store headers which define
on-media format in the include/ directory, but instead, store
them locally. This is because these headers "do not define any
kernel<->userspace interface".
Do so for UBI as well.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>