Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

[cascardo/linux.git] / drivers / virtio / virtio_pci_legacy.c

diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c
index 8c4e617..6d9e517 100644 (file)
--- a/drivers/virtio/virtio_pci_legacy.c
+++ b/drivers/virtio/virtio_pci_legacy.c
@@ -212,10 +212,18 @@ int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev)
                return -ENODEV;
        }
 
-       rc = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64));
-       if (rc)
-               rc = dma_set_mask_and_coherent(&pci_dev->dev,
-                                               DMA_BIT_MASK(32));
+       rc = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(64));
+       if (rc) {
+               rc = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(32));
+       } else {
+               /*
+                * The virtio ring base address is expressed as a 32-bit PFN,
+                * with a page size of 1 << VIRTIO_PCI_QUEUE_ADDR_SHIFT.
+                */
+               dma_set_coherent_mask(&pci_dev->dev,
+                               DMA_BIT_MASK(32 + VIRTIO_PCI_QUEUE_ADDR_SHIFT));
+       }
+
        if (rc)
                dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA.  Trying to continue, but this might not work.\n");