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Subject: Re: [PATCH -V1 4/9] arch/powerpc: Use vsid and segment offset to
 represent virtual address
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Sat, 30 Jun 2012 07:45:36 +1000
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On Fri, 2012-06-29 at 19:47 +0530, Aneesh Kumar K.V wrote:
>  
> +/* 78 bit power virtual address */
>  struct virt_addr {
> -       unsigned long addr;
> +       unsigned long vsid;
> +       unsigned long seg_off;
>  };

Do we really need to do that ? It's really nasty...

We are trying to add only a few bits, we get 12 for free by just using a
page number (4k based always, not PAGE_SHIFT based btw) no ? That should
get us going for a while....

Cheers,
Ben.