[I/OAT]: Utility functions for offloading sk_buff to iovec copies
Provides for pinning user space pages in memory, copying to iovecs,
and copying from sk_buffs including fragmented and chained sk_buffs.
Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 3078154..78b236c 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -333,5 +333,27 @@
int dma_async_device_register(struct dma_device *device);
void dma_async_device_unregister(struct dma_device *device);
+/* --- Helper iov-locking functions --- */
+
+struct dma_page_list {
+ char *base_address;
+ int nr_pages;
+ struct page **pages;
+};
+
+struct dma_pinned_list {
+ int nr_iovecs;
+ struct dma_page_list page_list[0];
+};
+
+struct dma_pinned_list *dma_pin_iovec_pages(struct iovec *iov, size_t len);
+void dma_unpin_iovec_pages(struct dma_pinned_list* pinned_list);
+
+dma_cookie_t dma_memcpy_to_iovec(struct dma_chan *chan, struct iovec *iov,
+ struct dma_pinned_list *pinned_list, unsigned char *kdata, size_t len);
+dma_cookie_t dma_memcpy_pg_to_iovec(struct dma_chan *chan, struct iovec *iov,
+ struct dma_pinned_list *pinned_list, struct page *page,
+ unsigned int offset, size_t len);
+
#endif /* CONFIG_DMA_ENGINE */
#endif /* DMAENGINE_H */