Re: RFC: direct MTD support for SquashFS

From: Ferenc Wagner
Date: Thu Mar 18 2010 - 12:55:40 EST


Peter Korsgaard <jacmet@xxxxxxxxxx> writes:

>>>>>> "Ferenc" == Ferenc Wagner <wferi@xxxxxxx> writes:
>
> Ferenc> In embedded systems, SquashFS over MTD would be a considerable
> Ferenc> win, as that would permit configuring without CONFIG_BLOCK.
> Ferenc> Please find attached a naive patch against 2.6.33 for this. It
> Ferenc> does not handle bad MTD blocks, that could be handled by gluebi
> Ferenc> (once you're willing to take the UBI overhead), or by a custom
> Ferenc> solution later.
>
> Ferenc> For now, 2.6.34 gained pluggable decompressors, so this patch
> Ferenc> does not apply anymore, though the main idea holds. My
> Ferenc> questions: is the community interested in integrating something
> Ferenc> like this, should this patch transformed into something
> Ferenc> acceptable, or am I a total lunatic? I don't know a thing
> Ferenc> about filesystem development, but willing to learn and
> Ferenc> refactor. Comments welcome.
>
> Nice, I have been thinking about that as well. What kind of size savings
> are you getting with this?

I could only compare apples to oranges before porting the patch to the
LZMA variant. So I refrain from that for a couple of days yet. But
meanwhile I started adding a pluggable backend framework to SquashFS,
and would much appreciate some comments about the applicability of this
idea. The patch is (intended to be) a no-op, applies on top of current
git (a3d3203e4bb40f253b1541e310dc0f9305be7c84).
--
Thanks,
Feri.