|
|
|
|
|
|
|
|
|
|
xen-devel
[Xen-devel] Re: [PATCH 7/8] xen/mmu: Introduce IDENTITY_FRAME_BIT
To: |
Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx> |
Subject: |
[Xen-devel] Re: [PATCH 7/8] xen/mmu: Introduce IDENTITY_FRAME_BIT |
From: |
Ian Campbell <Ian.Campbell@xxxxxxxxxxxxx> |
Date: |
Tue, 4 Jan 2011 16:26:15 +0000 |
Cc: |
Jeremy Fitzhardinge <jeremy@xxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, Stefano Stabellini <Stefano.Stabellini@xxxxxxxxxxxxx>, "linux-kernel@xxxxxxxxxxxxxxx" <linux-kernel@xxxxxxxxxxxxxxx>, Jan Beulich <JBeulich@xxxxxxxxxx>, Konrad Rzeszutek Wilk <konrad@xxxxxxxxxx>, "hpa@xxxxxxxxx" <hpa@xxxxxxxxx> |
Delivery-date: |
Tue, 04 Jan 2011 08:28:00 -0800 |
Envelope-to: |
www-data@xxxxxxxxxxxxxxxxxxx |
In-reply-to: |
<1293738517-7287-8-git-send-email-konrad.wilk@xxxxxxxxxx> |
List-help: |
<mailto:xen-devel-request@lists.xensource.com?subject=help> |
List-id: |
Xen developer discussion <xen-devel.lists.xensource.com> |
List-post: |
<mailto:xen-devel@lists.xensource.com> |
List-subscribe: |
<http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe> |
List-unsubscribe: |
<http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe> |
Organization: |
Citrix Systems, Inc. |
References: |
<1293738517-7287-1-git-send-email-konrad.wilk@xxxxxxxxxx> <1293738517-7287-8-git-send-email-konrad.wilk@xxxxxxxxxx> |
Sender: |
xen-devel-bounces@xxxxxxxxxxxxxxxxxxx |
On Thu, 2010-12-30 at 19:48 +0000, Konrad Rzeszutek Wilk wrote:
> @@ -52,9 +53,12 @@ static inline unsigned long pfn_to_mfn(unsigned long pfn)
>
> mfn = get_phys_to_machine(pfn);
>
> - if (mfn != INVALID_P2M_ENTRY)
> + if (mfn != INVALID_P2M_ENTRY) {
> mfn &= ~FOREIGN_FRAME_BIT;
>
> + if (mfn & IDENTITY_FRAME_BIT)
> + mfn &= ~IDENTITY_FRAME_BIT;
> + }
I don't think the inner-if buys us anything here and the whole thing is
equivalent to:
if (mfn != INVALID_P2M_ENTRY)
mfn &= ~(FOREIGN_FRAME_BIT|IDENTITY_FRAME_BIT);
Not sure if the FOREIGN_FRAME_BIT|IDENTITY_FRAME_BIT construct gets
enough use to be worthy of a #define FRAME_TYPE_MASK etc.
> return mfn;
> }
>
> diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
> index d98bd43..d470435 100644
> --- a/arch/x86/xen/mmu.c
> +++ b/arch/x86/xen/mmu.c
> @@ -425,10 +425,10 @@ unsigned long get_phys_to_machine(unsigned long pfn)
> * would be wrong.
> */
> if (p2m_top[topidx] == p2m_mid_identity)
> - return pfn;
> + return pfn | IDENTITY_FRAME_BIT;
It's probably worth defining IDENTITY_FRAME(m) in the pattern of
FOREIGN_FRAME(m).
Ian.
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
<Prev in Thread] |
Current Thread |
[Next in Thread>
|
- [Xen-devel] Re: [PATCH 7/8] xen/mmu: Introduce IDENTITY_FRAME_BIT,
Ian Campbell <=
|
|
|
|
|