2002-10-19 17:13:43

by arun4linux

[permalink] [raw]
Subject: mmap doubts

Hello,

As per our requirement, we are exporting the hardware personalities (Base Addresses) to the user space by implementing mmap(). (We write device driver for application specific PCI based controllers)

I would like to know how mmap() works actually. I meant the flow, address translations, etc.

Will there be any cache problem, if we use mmap()?

I also want to know how ring 3 and ring 0 matters in mmap() as we export ring 0 address to user space (ring 3). ( we work on intel platform).

Will there be any time delay if we use mmap() and access hardware in the user space?

It would be helpful, if you any one of you could explain/answer my doubts.

Have a nice time.

Warm Regards

Arun




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