Re: [PATCH 4/4] POWERPC: Merge 32 and 64-bit dma code
From: Christoph Hellwig <hch@lst.de>
Date: 2008-09-08 22:03:58
- if (unlikely(dev == NULL || dev->archdata.dma_ops == NULL))
+
+ if (unlikely(dev == NULL) || dev->archdata.dma_ops == NULL) {
+#ifdef CONFIG_PPC64
return NULL;
+#else
+ /* Use default on 32-bit if dma_ops is not set up */
+ return &dma_direct_ops;
+#endif
+ }
+This is okay for the transition, but I think long-term it should be setup for all busses.
quoted hunk ↗ jump to hunk
}@@ -132,7 +154,14 @@ static inline dma_addr_t dma_map_single_attrs(struct device *dev, struct dma_mapping_ops *dma_ops = get_dma_ops(dev); BUG_ON(!dma_ops); - return dma_ops->map_single(dev, cpu_addr, size, direction, attrs); + + if (dma_ops->map_single) + return dma_ops->map_single(dev, cpu_addr, size, direction, + attrs); + + return dma_ops->map_page(dev, virt_to_page(cpu_addr), + (unsigned long)cpu_addr % PAGE_SIZE, size, + direction, attrs);
Why would a dma ops implementation not provide map_single/unmap_single?