Merge branch 'net-netsec-Add-XDP-Support'

Ilias Apalodimas says:

====================
net: netsec: Add XDP Support

This is a respin of https://www.spinics.net/lists/netdev/msg526066.html
Since page_pool API fixes are merged into net-next we can now safely use
it's DMA mapping capabilities.

First patch changes the buffer allocation from napi/netdev_alloc_frag()
to page_pool API. Although this will lead to slightly reduced performance
(on raw packet drops only) we can use the API for XDP buffer recycling.
Another side effect is a slight increase in memory usage, due to using a
single page per packet.

The second patch adds XDP support on the driver.
There's a bunch of interesting options that come up due to the single
Tx queue.
Locking is needed(to avoid messing up the Tx queues since ndo_xdp_xmit
and the normal stack can co-exist). We also need to track down the
'buffer type' for TX and properly free or recycle the packet depending
on it's nature.

Changes since RFC:
- Bug fixes from Jesper and Maciej
- Added page pool API to retrieve the DMA direction

Changes since v1:
- Use page_pool_free correctly if xdp_rxq_info_reg() failed
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/socionext/Kconfig

@@ -26,6 +26,7 @@ config SNI_NETSEC
 	tristate "Socionext NETSEC ethernet support"
 	depends on (ARCH_SYNQUACER || COMPILE_TEST) && OF
 	select PHYLIB
+	select PAGE_POOL
 	select MII
 	---help---
 	  Enable to add support for the SocioNext NetSec Gigabit Ethernet

include/net/page_pool.h

@@ -112,6 +112,15 @@ static inline struct page *page_pool_dev_alloc_pages(struct page_pool *pool)
 	return page_pool_alloc_pages(pool, gfp);
 }
 
+/* get the stored dma direction. A driver might decide to treat 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)
+{
+	return pool->p.dma_dir;
+}
+
 struct page_pool *page_pool_create(const struct page_pool_params *params);
 
 void __page_pool_free(struct page_pool *pool);