xfrm: Add explicit dev to .xdo_dev_state_{add,delete,free}

Previously, device driver IPSec offload implementations would fall into
two categories:
1. Those that used xso.dev to determine the offload device.
2. Those that used xso.real_dev to determine the offload device.

The first category didn't work with bonding while the second did.
In a non-bonding setup the two pointers are the same.

This commit adds explicit pointers for the offload netdevice to
.xdo_dev_state_add() / .xdo_dev_state_delete() / .xdo_dev_state_free()
which eliminates the confusion and allows drivers from the first
category to work with bonding.

xso.real_dev now becomes a private pointer managed by the bonding
driver.

Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 39365fd2ea17..3d2f6c879311 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -147,8 +147,16 @@ enum {
 };
 
 struct xfrm_dev_offload {
+	/* The device for this offload.
+	 * Device drivers should not use this directly, as that will prevent
+	 * them from working with bonding device. Instead, the device passed
+	 * to the add/delete callbacks should be used.
+	 */
 	struct net_device	*dev;
 	netdevice_tracker	dev_tracker;
+	/* This is a private pointer used by the bonding driver.
+	 * Device drivers should not use it.
+	 */
 	struct net_device	*real_dev;
 	unsigned long		offload_handle;
 	u8			dir : 2;