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From: David Mosberger <davidm@napali.hpl.hp.com>
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Date: Mon, 20 May 2002 11:07:24 -0700
To: Sanket Rathi <sanket.rathi@cdac.ernet.in>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>, linux-kernel@vger.kernel.org
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>>>>> On Thu, 16 May 2002 21:24:10 +0530 (IST), Sanket Rathi <sanket.rathi@cdac.ernet.in> said:

  Sanket> No actually i don't want that for DMA it is for diffrent
  Sanket> requirment.  actually in our device there is a page table in
  Sanket> device which have virtual to physical address translation we
  Sanket> save virtual address in device and corresponding physical
  Sanket> address. but we can store only upto 44 bit information of
  Sanket> virtual address thats why i want that.

  Sanket> Can you help me in this

There is no way to limit virtual memory to 44 bits.  I don't know how
your device works, but just fyi: ia64 divides the address space into 8
equal-sized regions and user space applications tend to use at least
two regions (2 for text and 3 for data/stack).  This means that even
with the smallest page size, you'll have to take virtual address bits
61-63 into account.

Hope this helps,

	--david
--
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