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From: "sumanesh samanta" <sumanesh@hotmail.com>
To: linux-kernel@vger.kernel.org
Subject: kernel 2.4x - getting physical address for pages in HIGHMEM 
Date: Wed, 23 Jul 2003 00:09:54 +0000
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Hi,

I am facing a lot of problems in trying to get the physical address(actually 
bus address) from of page.

The most obvious answer, virt_to_bus(kmap(page)) seems to work for pages 
that are NOT  in high memory.

For pages in high memory, I have read up a lot of documentation, and mailing 
list questions, but the only thing that seems to work for me is,
(page-mem_map)<<PAGE_SHIFT

Now, the mail i got this from says that this would work only when  mem_map 
[] starts at zero.

I am pretty confused here, this seems to be a obvious problem, why does 
Linux not have a pretty macro or function that would work in all situations?

PS. please cc me in any answers, as I am not subscribed to this list.

Thanks
sumanesh

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