[v4,1/7] s390/ism: Set DMA coherent mask

Message ID 20230104120543.308933-2-schnelle@linux.ibm.com
State New
Headers
Series iommu/dma: s390 DMA API conversion and optimized IOTLB flushing |

Commit Message

Niklas Schnelle Jan. 4, 2023, 12:05 p.m. UTC
  A future change will convert the DMA API implementation from the
architecture specific arch/s390/pci/pci_dma.c to using the common code
drivers/iommu/dma-iommu.c which the utilizes the same IOMMU hardware
through the s390-iommu driver. Unlike the s390 specific DMA API this
requires devices to correctly call set the coherent mask to be allowed
to use IOVAs >2^32 in dma_alloc_coherent(). This was however not done
for ISM devices. ISM requires such addresses since currently the DMA
aperture for PCI devices starts at 2^32 and all calls to
dma_alloc_coherent() would thus fail.

Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
---
 drivers/s390/net/ism_drv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
  

Comments

Matthew Rosato Jan. 17, 2023, 3:09 p.m. UTC | #1
On 1/4/23 7:05 AM, Niklas Schnelle wrote:
> A future change will convert the DMA API implementation from the
> architecture specific arch/s390/pci/pci_dma.c to using the common code
> drivers/iommu/dma-iommu.c which the utilizes the same IOMMU hardware
> through the s390-iommu driver. Unlike the s390 specific DMA API this
> requires devices to correctly call set the coherent mask to be allowed
> to use IOVAs >2^32 in dma_alloc_coherent(). This was however not done
> for ISM devices. ISM requires such addresses since currently the DMA
> aperture for PCI devices starts at 2^32 and all calls to
> dma_alloc_coherent() would thus fail.
> 
> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
  

Patch

diff --git a/drivers/s390/net/ism_drv.c b/drivers/s390/net/ism_drv.c
index dfd401d9e362..aba03b613296 100644
--- a/drivers/s390/net/ism_drv.c
+++ b/drivers/s390/net/ism_drv.c
@@ -557,7 +557,7 @@  static int ism_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	if (ret)
 		goto err_disable;
 
-	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
+	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
 	if (ret)
 		goto err_resource;