UBI fastmap updates

[Shmulik Ladkani]

Hi,

On Thu, 2 Aug 2012 19:45:38 +0200 Richard Weinberger <richard at nod.at> wrote:
> Okay, then let's explicitly reserve a few PEBs for fastmap.
> This should be very easy task.

Need to consider what's expected when migrating from a former non-FM
UBI system to an FM enabled system, in the case where all PEBs where
consumed (reserved) in the former system.

> How much PEB should be reserved? 2 x sizeof(fastmap)?

Since FM does not use EBA's atomic LEB change when writing the new
fastmap, but instead implements its own FM "leb change" internally -
then reserving 2x is needed if we'd like to avoid reusing the same
fastmap PEB.

Regards,
Shmulik