1 files changed, 29 insertions, 5 deletions

diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helpers.h
index 1d397c1a0043..873631c79ab1 100644
--- a/include/net/page_pool/helpers.h
+++ b/include/net/page_pool/helpers.h
@@ -52,13 +52,15 @@
 #ifndef _NET_PAGE_POOL_HELPERS_H
 #define _NET_PAGE_POOL_HELPERS_H
 
+#include <linux/dma-mapping.h>
+
 #include <net/page_pool/types.h>
 
 #ifdef CONFIG_PAGE_POOL_STATS
 /* Deprecated driver-facing API, use netlink instead */
 int page_pool_ethtool_stats_get_count(void);
 u8 *page_pool_ethtool_stats_get_strings(u8 *data);
-u64 *page_pool_ethtool_stats_get(u64 *data, void *stats);
+u64 *page_pool_ethtool_stats_get(u64 *data, const void *stats);
 
 bool page_pool_get_stats(const struct page_pool *pool,
 			 struct page_pool_stats *stats);
@@ -73,7 +75,7 @@ static inline u8 *page_pool_ethtool_stats_get_strings(u8 *data)
 	return data;
 }
 
-static inline u64 *page_pool_ethtool_stats_get(u64 *data, void *stats)
+static inline u64 *page_pool_ethtool_stats_get(u64 *data, const void *stats)
 {
 	return data;
 }
@@ -204,8 +206,8 @@ static inline void *page_pool_dev_alloc_va(struct page_pool *pool,
  * Get the stored dma direction. A driver might decide to store this locally
  * and avoid the extra cache line from page_pool to determine the direction.
  */
-static
-inline enum dma_data_direction page_pool_get_dma_dir(struct page_pool *pool)
+static inline enum dma_data_direction
+page_pool_get_dma_dir(const struct page_pool *pool)
 {
 	return pool->p.dma_dir;
 }
@@ -370,7 +372,7 @@ static inline void page_pool_free_va(struct page_pool *pool, void *va,
  * Fetch the DMA address of the page. The page pool to which the page belongs
  * must had been created with PP_FLAG_DMA_MAP.
  */
-static inline dma_addr_t page_pool_get_dma_addr(struct page *page)
+static inline dma_addr_t page_pool_get_dma_addr(const struct page *page)
 {
 	dma_addr_t ret = page->dma_addr;
 
@@ -395,6 +397,28 @@ static inline bool page_pool_set_dma_addr(struct page *page, dma_addr_t addr)
 	return false;
 }
 
+/**
+ * page_pool_dma_sync_for_cpu - sync Rx page for CPU after it's written by HW
+ * @pool: &page_pool the @page belongs to
+ * @page: page to sync
+ * @offset: offset from page start to "hard" start if using PP frags
+ * @dma_sync_size: size of the data written to the page
+ *
+ * Can be used as a shorthand to sync Rx pages before accessing them in the
+ * driver. Caller must ensure the pool was created with ``PP_FLAG_DMA_MAP``.
+ * Note that this version performs DMA sync unconditionally, even if the
+ * associated PP doesn't perform sync-for-device.
+ */
+static inline void page_pool_dma_sync_for_cpu(const struct page_pool *pool,
+					      const struct page *page,
+					      u32 offset, u32 dma_sync_size)
+{
+	dma_sync_single_range_for_cpu(pool->p.dev,
+				      page_pool_get_dma_addr(page),
+				      offset + pool->p.offset, dma_sync_size,
+				      page_pool_get_dma_dir(pool));
+}
+
 static inline bool page_pool_put(struct page_pool *pool)
 {
 	return refcount_dec_and_test(&pool->user_cnt);