diff options
| author | Vladimir Oltean <vladimir.oltean@nxp.com> | 2021-06-11 22:01:24 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-06-11 12:45:38 -0700 |
| commit | 4e50025129efabb07714c1f27a80526897da374b (patch) | |
| tree | bef1017e42111f0e3ffc5d6119ea58a677b6aa35 /net/dsa/slave.c | |
| parent | 6c0de59b3d735f4c8c704dae30db540204b496ec (diff) | |
net: dsa: generalize overhead for taggers that use both headers and trailers
Some really really weird switches just couldn't decide whether to use a
normal or a tail tagger, so they just did both.
This creates problems for DSA, because we only have the concept of an
'overhead' which can be applied to the headroom or to the tailroom of
the skb (like for example during the central TX reallocation procedure),
depending on the value of bool tail_tag, but not to both.
We need to generalize DSA to cater for these odd switches by
transforming the 'overhead / tail_tag' pair into 'needed_headroom /
needed_tailroom'.
The DSA master's MTU is increased to account for both.
The flow dissector code is modified such that it only calls the DSA
adjustment callback if the tagger has a non-zero header length.
Taggers are trivially modified to declare either needed_headroom or
needed_tailroom, based on the tail_tag value that they currently
declare.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/dsa/slave.c')
| -rw-r--r-- | net/dsa/slave.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/net/dsa/slave.c b/net/dsa/slave.c index d4756b920108..3ca509eb284d 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -1569,7 +1569,7 @@ int dsa_slave_change_mtu(struct net_device *dev, int new_mtu) mtu_limit = min_t(int, master->max_mtu, dev->max_mtu); old_master_mtu = master->mtu; - new_master_mtu = largest_mtu + cpu_dp->tag_ops->overhead; + new_master_mtu = largest_mtu + dsa_tag_protocol_overhead(cpu_dp->tag_ops); if (new_master_mtu > mtu_limit) return -ERANGE; @@ -1605,7 +1605,7 @@ int dsa_slave_change_mtu(struct net_device *dev, int new_mtu) out_port_failed: if (new_master_mtu != old_master_mtu) dsa_port_mtu_change(cpu_dp, old_master_mtu - - cpu_dp->tag_ops->overhead, + dsa_tag_protocol_overhead(cpu_dp->tag_ops), true); out_cpu_failed: if (new_master_mtu != old_master_mtu) @@ -1824,10 +1824,8 @@ void dsa_slave_setup_tagger(struct net_device *slave) const struct dsa_port *cpu_dp = dp->cpu_dp; struct net_device *master = cpu_dp->master; - if (cpu_dp->tag_ops->tail_tag) - slave->needed_tailroom = cpu_dp->tag_ops->overhead; - else - slave->needed_headroom = cpu_dp->tag_ops->overhead; + slave->needed_headroom = cpu_dp->tag_ops->needed_headroom; + slave->needed_tailroom = cpu_dp->tag_ops->needed_tailroom; /* Try to save one extra realloc later in the TX path (in the master) * by also inheriting the master's needed headroom and tailroom. * The 8021q driver also does this. |