[net-next PATCH RFC 1/8] page_pool: add helper functions for DMA

[Jesper Dangaard Brouer <brouer@redhat.com>]

From: Ilias Apalodimas <ilias.apalodimas@linaro.org>

Add helper functions for retreiving dma_addr_t stored in page_private and
unmapping dma addresses, mapped via the page_pool API.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 include/net/page_pool.h |    6 ++++++
 net/core/page_pool.c    |    7 +++++++
 2 files changed, 13 insertions(+)

diff --git a/include/net/page_pool.h b/include/net/page_pool.h
index 694d055e01ef..439f9183d4cd 100644
--- a/include/net/page_pool.h
+++ b/include/net/page_pool.h
@@ -111,6 +111,8 @@ struct page_pool *page_pool_create(const struct page_pool_params *params);
 
 void page_pool_destroy(struct page_pool *pool);
 
+void page_pool_unmap_page(struct page_pool *pool, struct page *page);
+
 /* Never call this directly, use helpers below */
 void __page_pool_put_page(struct page_pool *pool,
 			  struct page *page, bool allow_direct);
@@ -141,4 +143,8 @@ static inline bool is_page_pool_compiled_in(void)
 #endif
 }
 
+static inline dma_addr_t page_pool_get_dma_addr(struct page *page)
+{
+	return page_private(page);
+}
 #endif /* _NET_PAGE_POOL_H */
diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 43a932cb609b..26e14a17a67c 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -184,6 +184,13 @@ static void __page_pool_clean_page(struct page_pool *pool,
 	set_page_private(page, 0);
 }
 
+/* unmap the page and clean our state */
+void page_pool_unmap_page(struct page_pool *pool, struct page *page)
+{
+	__page_pool_clean_page(pool, page);
+}
+EXPORT_SYMBOL(page_pool_unmap_page);
+
 /* Return a page to the page allocator, cleaning up our state */
 static void __page_pool_return_page(struct page_pool *pool, struct page *page)
 {