[PATCH v3 1/7] s390/ism: Set DMA coherent mask

Niklas Schnelle
2023-01-02T11:56:47Z

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.

Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
---
v1 -> v2:
- Use dma_set_mask_and_coherent() (Christoph Hellwig)

drivers/s390/net/ism_drv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

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;

--
2.34.1