Re: [RFC 2/4] virtio: Override device's DMA OPS with virtio_direct_dma_ops selectively
From: Christoph Hellwig <hch@infradead.org>
Date: 2018-07-30 09:25:55
Also in:
lkml
+const struct dma_map_ops virtio_direct_dma_ops;
This belongs into a header if it is non-static. If you only use it in this file anyway please mark it static and avoid a forward declaration.
quoted hunk ↗ jump to hunk
+ int virtio_finalize_features(struct virtio_device *dev) { int ret = dev->config->finalize_features(dev);@@ -174,6 +176,9 @@ int virtio_finalize_features(struct virtio_device *dev) if (ret) return ret; + if (virtio_has_iommu_quirk(dev)) + set_dma_ops(dev->dev.parent, &virtio_direct_dma_ops);
This needs a big fat comment explaining what is going on here. Also not new, but I find the existance of virtio_has_iommu_quirk and its name horribly confusing. It might be better to open code it here once only a single caller is left.