Introduce new xdp_feature NETDEV_XDP_ACT_ZC_SG that will be used to
find out if user space that wants to do ZC multi-buffer will be able to
do so against underlying ZC driver.
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx>
---
include/uapi/linux/netdev.h | 6 ++++--
net/xdp/xsk_buff_pool.c | 6 ++++++
2 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index 639524b59930..c293014a4197 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -24,6 +24,8 @@
* XDP buffer support in the driver napi callback.
* @NETDEV_XDP_ACT_NDO_XMIT_SG: This feature informs if netdev implements
* non-linear XDP buffer support in ndo_xdp_xmit callback.
+ * @NETDEV_XDP_ACT_ZC_SG: This feature informs if netdev implements
+ * non-linear XDP buffer support in AF_XDP zero copy mode.
*/
enum netdev_xdp_act {
NETDEV_XDP_ACT_BASIC = 1,
@@ -33,8 +35,8 @@ enum netdev_xdp_act {
NETDEV_XDP_ACT_HW_OFFLOAD = 16,
NETDEV_XDP_ACT_RX_SG = 32,
NETDEV_XDP_ACT_NDO_XMIT_SG = 64,
-
- NETDEV_XDP_ACT_MASK = 127,
+ NETDEV_XDP_ACT_ZC_SG = 128,
+ NETDEV_XDP_ACT_MASK = 255,
};
enum {
diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c
index 0a9f8ea68de3..c8d65e5883ec 100644
--- a/net/xdp/xsk_buff_pool.c
+++ b/net/xdp/xsk_buff_pool.c
@@ -189,6 +189,12 @@ int xp_assign_dev(struct xsk_buff_pool *pool,
goto err_unreg_pool;
}
+ if (!(netdev->xdp_features & NETDEV_XDP_ACT_ZC_SG) &&
+ flags & XDP_USE_SG) {
+ err = -EOPNOTSUPP;
+ goto err_unreg_pool;
+ }
+
bpf.command = XDP_SETUP_XSK_POOL;
bpf.xsk.pool = pool;
bpf.xsk.queue_id = queue_id;
--
2.34.1
