@@ -548,6 +632,17 @@ static int gntdev_open(struct inode *inode, struct
file *flip)
}
flip->private_data = priv;
+#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
+ priv->dma_dev = gntdev_miscdev.this_device;
+
+ /*
+ * The device is not spawn from a device tree, so arch_setup_dma_ops
+ * is not called, thus leaving the device with dummy DMA ops.
+ * Fix this call of_dma_configure() with a NULL node to set
+ * default DMA ops.
+ */
+ of_dma_configure(priv->dma_dev, NULL);
Please note, that the code above will need a change while
applying to the mainline kernel because of API changes [1].
Unfortunately, current Xen tip kernel tree is v4.17-rc5 based,
so I cannot make the change in this patch now.
The change is trivial and requires:
-of_dma_configure(priv->dma_dev, NULL);
+of_dma_configure(priv->dma_dev, NULL, true);
+#endif
pr_debug("priv %p\n", priv);
return 0;
[1]
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3d6ce86ee79465e1b1b6e287f8ea26b553fc768e
