[lkml]   [2012]   [Aug]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: UBI fastmap updates

On Thu, 2012-08-02 at 18:32 +0200, Richard Weinberger wrote:
> > This should not happen. Fastmap should _reserve_ enough of PEBs for it
> > to operate. It should always find the PEB to write.
> What is the benefit?
> IOW what is wrong with the current approach?

Several reasons. The main is: fastmap will start consuming PEBs reserved
for volumes when the amount of available PEBs is just enough to map all
LEBs. This will break UBI liability.

> Why?
> If everything goes wrong, fastmap makes sure that no fastmap is on
> flash.
> In case of a powercut we fall back to scanning mode.
> R/O mode is overkill IMHO.

So can I interpret this the following way. Not only fastmap give no
guarantees that it exists after an unclean reboot, it does not even give
guarantees that it exists after a clean reboot.

Unless I am confused, the fastmap design is over-simplified.

Best Regards,
Artem Bityutskiy
[unhandled content-type:application/pgp-signature]
 \ /
  Last update: 2012-08-02 19:01    [W:0.075 / U:0.264 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site