From: David Gibson
This improves I/O performance for guests using the PAPR paravirtualization
interface by making the H_PUT_TCE hcall faster, by implementing it in
real mode. H_PUT_TCE is used for updating virtual IOMMU tables, and is
used both for virtual I/O and for real I/O in the PAPR interf
On 11.05.2011, at 12:46, Paul Mackerras wrote:
> From: David Gibson
>
> This improves I/O performance for guests using the PAPR paravirtualization
> interface by making the H_PUT_TCE hcall faster, by implementing it in
> real mode. H_PUT_TCE is used for updating virtual IOMMU tables, and is
>
On Tue, 2011-05-17 at 10:01 +0200, Alexander Graf wrote:
> I'm not sure I fully understand how this is supposed to work. If the
> tables are kept inside the kernel, how does userspace get to know
> where to DMA to?
The guest gets a dma range from the device-tree which is the range of
device-side d
On 17.05.2011, at 11:11, Benjamin Herrenschmidt wrote:
> On Tue, 2011-05-17 at 10:01 +0200, Alexander Graf wrote:
>> I'm not sure I fully understand how this is supposed to work. If the
>> tables are kept inside the kernel, how does userspace get to know
>> where to DMA to?
>
> The guest gets a
On Tue, 2011-05-17 at 11:31 +0200, Alexander Graf wrote:
> On 17.05.2011, at 11:11, Benjamin Herrenschmidt wrote:
>
> > On Tue, 2011-05-17 at 10:01 +0200, Alexander Graf wrote:
> >> I'm not sure I fully understand how this is supposed to work. If the
> >> tables are kept inside the kernel, how doe
On 17.05.2011, at 11:35, Benjamin Herrenschmidt wrote:
> On Tue, 2011-05-17 at 11:31 +0200, Alexander Graf wrote:
>> On 17.05.2011, at 11:11, Benjamin Herrenschmidt wrote:
>>
>>> On Tue, 2011-05-17 at 10:01 +0200, Alexander Graf wrote:
I'm not sure I fully understand how this is supposed to
