diff mbox series

s390x/pci: Set the iommu region size as guest wants

Message ID 1546968819-8166-1-git-send-email-pmorel@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series s390x/pci: Set the iommu region size as guest wants | expand

Commit Message

Pierre Morel Jan. 8, 2019, 5:33 p.m. UTC
The size of the accessible iommu memory region in the guest
is calculated by the gues as:
    (PCI Address Limit) - (PCI Base Address) + 1.

Let's use this value to limit the IOMMU region size.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
---
 hw/s390x/s390-pci-bus.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Cornelia Huck Jan. 9, 2019, 12:59 p.m. UTC | #1
On Tue,  8 Jan 2019 18:33:39 +0100
Pierre Morel <pmorel@linux.ibm.com> wrote:

> The size of the accessible iommu memory region in the guest
> is calculated by the gues as:

s/gues/guest/

>     (PCI Address Limit) - (PCI Base Address) + 1.
> 
> Let's use this value to limit the IOMMU region size.

These are values provided by the guest in the mpcifc call, aren't they?
Let's mention that in the patch description, so it is more obvious :)

> 
> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
> ---
>  hw/s390x/s390-pci-bus.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
> index 69e0671..e97696a 100644
> --- a/hw/s390x/s390-pci-bus.c
> +++ b/hw/s390x/s390-pci-bus.c
> @@ -660,7 +660,7 @@ void s390_pci_iommu_enable(S390PCIIOMMU *iommu)
>      char *name = g_strdup_printf("iommu-s390-%04x", iommu->pbdev->uid);
>      memory_region_init_iommu(&iommu->iommu_mr, sizeof(iommu->iommu_mr),
>                               TYPE_S390_IOMMU_MEMORY_REGION, OBJECT(&iommu->mr),
> -                             name, iommu->pal + 1);
> +                             name, iommu->pal - iommu->pba + 1);
>      iommu->enabled = true;
>      memory_region_add_subregion(&iommu->mr, 0, MEMORY_REGION(&iommu->iommu_mr));
>      g_free(name);
Pierre Morel Jan. 10, 2019, 12:50 p.m. UTC | #2
On 09/01/2019 13:59, Cornelia Huck wrote:
> On Tue,  8 Jan 2019 18:33:39 +0100
> Pierre Morel <pmorel@linux.ibm.com> wrote:
> 
>> The size of the accessible iommu memory region in the guest
>> is calculated by the gues as:
> 
> s/gues/guest/
> 
>>      (PCI Address Limit) - (PCI Base Address) + 1.
>>
>> Let's use this value to limit the IOMMU region size.
> 
> These are values provided by the guest in the mpcifc call, aren't they?
> Let's mention that in the patch description, so it is more obvious :)
> 

OK thanks.

Regards,
Pierre
diff mbox series

Patch

diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index 69e0671..e97696a 100644
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -660,7 +660,7 @@  void s390_pci_iommu_enable(S390PCIIOMMU *iommu)
     char *name = g_strdup_printf("iommu-s390-%04x", iommu->pbdev->uid);
     memory_region_init_iommu(&iommu->iommu_mr, sizeof(iommu->iommu_mr),
                              TYPE_S390_IOMMU_MEMORY_REGION, OBJECT(&iommu->mr),
-                             name, iommu->pal + 1);
+                             name, iommu->pal - iommu->pba + 1);
     iommu->enabled = true;
     memory_region_add_subregion(&iommu->mr, 0, MEMORY_REGION(&iommu->iommu_mr));
     g_free(name);