mmap for JFFS2

[alex_khrist at km.ru]

Hi!
I use JFFS2 on NAND flash. Some apps require memory mapped file
opened with MAP_SHARED for read/write. But 'mmap' returns EINVAL,
since 'writepage'doesn't implemented for JFFS2 (even in 2.6.22 kernel).
It seems what I have to do it by myself. But I have some doubts.
Why it is not imlemented yet? What the troubles occur for JFFS2 developers?
Does anybody know some workarounds?
P.S. I can't change anything within given apps.

WBR, Alex Khristianovsky.
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