How to do a mmap ?

[Jerome de Vivie <jerome.devivie@free.fr>]

I'm currently writting a module. I use a file from kernelspace. Instead
of using "f_op" read/write calls, i would like to mmap this file into
the kernel memory and use it as a contiguous space.

I've try to do it by calling "do_mmap", but when i access the memory
from another process inside an "ioctl", i get an Oops with a
"segmentation fault". The address returned doesn't seem to be in good
segment for my module. 

I would like to have a valid address of the begining of the mmaped file
plus a "length", and being able to use this space when the module is
requested from processes. I also want to be able to remap this space if
the file grows. I don't know which functions or kernel structures i
should use.  Could you help me a bit ? 


Kind regards,

j.

PS: CC added to me are welcome.

-- 
Jérôme de Vivie
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