prefect(page) is a common thing to be called from drivers. Add
netmem_prefetch that can be called on generic netmem. Skips the prefetch
for net_iovs.

Signed-off-by: Mina Almasry <almasrymina@google.com>
---
 include/net/netmem.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/net/netmem.h b/include/net/netmem.h
index 8a6e20be4b9d..923c47147aa8 100644
--- a/include/net/netmem.h
+++ b/include/net/netmem.h
@@ -171,4 +171,11 @@ static inline unsigned long netmem_get_dma_addr(netmem_ref netmem)
 	return __netmem_clear_lsb(netmem)->dma_addr;
 }
 
+static inline void netmem_prefetch(netmem_ref netmem)
+{
+	if (netmem_is_net_iov(netmem))
+		return;
+
+	prefetch(netmem_to_page(netmem));
+}
 #endif /* _NET_NETMEM_H */
-- 
2.47.0.163.g1226f6d8fa-goog