* Re: How to ensure that different peripherals getting different IOVA address in kernel?
2015-09-23 1:55 ` How to ensure that different peripherals getting different IOVA address in kernel? chenfeng
@ 2015-09-23 2:42 ` Jiang Liu
2015-09-23 12:08 ` Robin Murphy
1 sibling, 0 replies; 3+ messages in thread
From: Jiang Liu @ 2015-09-23 2:42 UTC (permalink / raw)
To: chenfeng, joro, iommu, linux-kernel, rcallicotte, robin.murphy
Cc: Dan zhao, qijiwen, Peter Panshilin, Suzhuangluan, Yiping Xu,
Wangfei (William, Euler)
On 2015/9/23 9:55, chenfeng wrote:
> Hi all,
>
> In IOMMU architecture , how to make two different peripherals share the same page table ?
>
> In other words , is there a mechanism or structure to make two peripherals get completely different address.
>
> eg:
>
> peri-A、peri-B and peri-C share the same iova address 0-1G for some performance requests.
>
> So the A,B,C need to use the same IOVA generator to ensure this,but I don't find an architecture to make this.
>
> Any help will be appreciated.
Hi Chenfeng,
Seems IOMMU group may help you, please take a look at
Documentation/vfio.txt.
Thanks!
Gerry
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: How to ensure that different peripherals getting different IOVA address in kernel?
2015-09-23 1:55 ` How to ensure that different peripherals getting different IOVA address in kernel? chenfeng
2015-09-23 2:42 ` Jiang Liu
@ 2015-09-23 12:08 ` Robin Murphy
1 sibling, 0 replies; 3+ messages in thread
From: Robin Murphy @ 2015-09-23 12:08 UTC (permalink / raw)
To: chenfeng, joro, iommu, linux-kernel, rcallicotte, jiang.liu
Cc: Dan zhao, qijiwen, Peter Panshilin, Suzhuangluan, Yiping Xu,
Wangfei (William, Euler)
On 23/09/15 02:55, chenfeng wrote:
> Hi all,
>
> In IOMMU architecture , how to make two different peripherals share the same page table ?
>
> In other words , is there a mechanism or structure to make two peripherals get completely different address.
>
> eg:
>
> peri-A、peri-B and peri-C share the same iova address 0-1G for some performance requests.
>
> So the A,B,C need to use the same IOVA generator to ensure this,but I don't find an architecture to make this.
This is what IOMMU domains are all about: devices in one domain are
isolated from devices in different domains, so all you need to do is
make sure all devices that want to share buffers are attached to the
same domain, then they will all share that domain's IOVA space.
Robin.
>
> Any help will be appreciated.
>
> Puck
>
>
^ permalink raw reply [flat|nested] 3+ messages in thread