diff options
| author | Sven Eckelmann <sven@narfation.org> | 2023-07-27 10:13:43 +0200 |
|---|---|---|
| committer | Simon Wunderlich <sw@simonwunderlich.de> | 2023-08-03 21:11:42 +0200 |
| commit | 112cbcb4af90c4b108b120a28089872d2234a350 (patch) | |
| tree | ceee6971b2cb36529ea02c892675f6a1894e2c6e /net/batman-adv | |
| parent | e4b817804579624b47823d87e647ec6c3d3ab827 (diff) | |
batman-adv: Check hardif MTU against runtime MTU
If the MTU of the soft/mesh interface was already reduced (enough), it is
not necessary to print a warning about a hard interface not having a MTU to
transport ethernet payloads of 1500 bytes.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Diffstat (limited to 'net/batman-adv')
| -rw-r--r-- | net/batman-adv/hard-interface.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c index 41c1ad33d009..5a4ff9a81e74 100644 --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -9,6 +9,7 @@ #include <linux/atomic.h> #include <linux/byteorder/generic.h> +#include <linux/compiler.h> #include <linux/container_of.h> #include <linux/errno.h> #include <linux/gfp.h> @@ -699,9 +700,14 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface, struct batadv_priv *bat_priv; __be16 ethertype = htons(ETH_P_BATMAN); int max_header_len = batadv_max_header_len(); + unsigned int required_mtu; + unsigned int hardif_mtu; int ret; - if (hard_iface->net_dev->mtu < ETH_MIN_MTU + max_header_len) + hardif_mtu = READ_ONCE(hard_iface->net_dev->mtu); + required_mtu = READ_ONCE(soft_iface->mtu) + max_header_len; + + if (hardif_mtu < ETH_MIN_MTU + max_header_len) return -EINVAL; if (hard_iface->if_status != BATADV_IF_NOT_IN_USE) @@ -734,18 +740,18 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface, hard_iface->net_dev->name); if (atomic_read(&bat_priv->fragmentation) && - hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len) + hardif_mtu < required_mtu) batadv_info(hard_iface->soft_iface, "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to %i would solve the problem.\n", - hard_iface->net_dev->name, hard_iface->net_dev->mtu, - ETH_DATA_LEN + max_header_len); + hard_iface->net_dev->name, hardif_mtu, + required_mtu); if (!atomic_read(&bat_priv->fragmentation) && - hard_iface->net_dev->mtu < ETH_DATA_LEN + max_header_len) + hardif_mtu < required_mtu) batadv_info(hard_iface->soft_iface, "The MTU of interface %s is too small (%i) to handle the transport of batman-adv packets. If you experience problems getting traffic through try increasing the MTU to %i.\n", - hard_iface->net_dev->name, hard_iface->net_dev->mtu, - ETH_DATA_LEN + max_header_len); + hard_iface->net_dev->name, hardif_mtu, + required_mtu); if (batadv_hardif_is_iface_up(hard_iface)) batadv_hardif_activate_interface(hard_iface); |