[PATCH AUTOSEL 4.19 6/9] vxlan: Copy needed_tailroom from lowerdev

[Sasha Levin <sashal@kernel.org>]

From: Sven Eckelmann <sven@narfation.org>

[ Upstream commit a5e74021e84bb5eadf760aaf2c583304f02269be ]

While vxlan doesn't need any extra tailroom, the lowerdev might need it. In
that case, copy it over to reduce the chance for additional (re)allocations
in the transmit path.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Link: https://lore.kernel.org/r/20201126125247.1047977-2-sven@narfation.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/vxlan.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 8481a21fe7afb..66fffbd64a33f 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -3182,6 +3182,8 @@ static void vxlan_config_apply(struct net_device *dev,
 		needed_headroom = lowerdev->hard_header_len;
 		needed_headroom += lowerdev->needed_headroom;
 
+		dev->needed_tailroom = lowerdev->needed_tailroom;
+
 		max_mtu = lowerdev->mtu - (use_ipv6 ? VXLAN6_HEADROOM :
 					   VXLAN_HEADROOM);
 		if (max_mtu < ETH_MIN_MTU)
-- 
2.27.0