From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joerg Roedel <joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org>
Subject: Re: Bug: Freeing dma regions
Date: Wed, 2 Mar 2016 13:35:19 +0100
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To: David Kiarie <davidkiarie4-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
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On Wed, Mar 02, 2016 at 11:40:04AM +0300, David Kiarie wrote:
> What effect is setting the value next_bit to last invalidated index
> supposed to have ?

The idea is to safe the IOTLB flush by not re-using the address-range
until the allocator wraps around to 0 again. We only allocate address
ranges between next_bit and end-of-range. This way we don't need a flush
after every unmap operation.



	Joerg