Ivan Khoronzhuk says:

====================
net: ethernet: ti: cpsw: fix vlan mcast

The cpsw holds separate mcast entires for vlan entries. At this moment
driver adds only not vlan mcast addresses, omitting vlan/mcast entries.
As result mcast for vlans doesn't work. It can be fixed by adding same
mcast entries for every created vlan, but this patchseries uses more
sophisticated way and allows to create mcast entries only for vlans
that really require it. Generic functions from this series can be
reused for fixing vlan and macvlan unicast.

Simple example of ALE table before and after this series, having same
mcast entries as for vlan 100 as for real device (reserved vlan 2),
and one mcast address only for vlan 100 - 01:1b:19:00:00:00.

<---- Before this patchset ---->
vlan , vid = 2, untag_force = 0x5, reg_mcast = 0x5, mem_list = 0x5
mcast, vid = 2, addr = ff:ff:ff:ff:ff:ff, port_mask = 0x1
ucast, vid = 2, addr = 74:da:ea:47:7d:9d, persistant, port_num = 0x0
vlan , vid = 0, untag_force = 0x7, reg_mcast = 0x0, mem_list = 0x7
mcast, vid = 2, addr = 33:33:00:00:00:01, port_mask = 0x1
mcast, vid = 2, addr = 01:00:5e:00:00:01, port_mask = 0x1
vlan , vid = 1, untag_force = 0x3, reg_mcast = 0x3, mem_list = 0x3
mcast, vid = 1, addr = ff:ff:ff:ff:ff:ff, port_mask = 0x1
ucast, vid = 1, addr = 74:da:ea:47:7d:9c, persistant, port_num = 0x0
mcast, vid = 1, addr = 33:33:00:00:00:01, port_mask = 0x1
mcast, vid = 1, addr = 01:00:5e:00:00:01, port_mask = 0x1
mcast, vid = 2, addr = 01:80:c2:00:00:00, port_mask = 0x1
mcast, vid = 2, addr = 01:80:c2:00:00:03, port_mask = 0x1
mcast, vid = 2, addr = 01:80:c2:00:00:0e, port_mask = 0x1
mcast, vid = 1, addr = 01:80:c2:00:00:00, port_mask = 0x1
mcast, vid = 1, addr = 01:80:c2:00:00:03, port_mask = 0x1
mcast, vid = 1, addr = 01:80:c2:00:00:0e, port_mask = 0x1
mcast, vid = 2, addr = 33:33:ff:47:7d:9d, port_mask = 0x1
mcast, vid = 2, addr = 33:33:00:00:00:fb, port_mask = 0x1
mcast, vid = 2, addr = 33:33:00:01:00:03, port_mask = 0x1
mcast, vid = 1, addr = 33:33:ff:47:7d:9c, port_mask = 0x1
mcast, vid = 1, addr = 33:33:00:00:00:fb, port_mask = 0x1
mcast, vid = 1, addr = 33:33:00:01:00:03, port_mask = 0x1
mcast, vid = 1, addr = 01:00:5e:00:00:fb, port_mask = 0x1
mcast, vid = 1, addr = 01:00:5e:00:00:fc, port_mask = 0x1
vlan , vid = 100, untag_force = 0x0, reg_mcast = 0x5, mem_list = 0x5
ucast, vid = 100, addr = 74:da:ea:47:7d:9d, persistant, port_num = 0x0
mcast, vid = 100, addr = ff:ff:ff:ff:ff:ff, port_mask = 0x1
mcast, vid = 2, addr = 01:1b:19:00:00:00, port_mask = 0x1
			 ^^^
 Here mcast entry (ptpl2), has to be added only for vlan 100
 but added for reserved vlan 2...that's not enough.

<---- After this patchset ---->
vlan , vid = 2, untag_force = 0x5, reg_mcast = 0x5, mem_list = 0x5
mcast, vid = 2, addr = ff:ff:ff:ff:ff:ff, port_mask = 0x1
ucast, vid = 2, addr = 74:da:ea:47:7d:9d, persistant, port_num = 0x0
vlan , vid = 0, untag_force = 0x7, reg_mcast = 0x0, mem_list = 0x7
mcast, vid = 2, addr = 33:33:00:00:00:01, port_mask = 0x1
mcast, vid = 2, addr = 01:00:5e:00:00:01, port_mask = 0x1
vlan , vid = 1, untag_force = 0x3, reg_mcast = 0x3, mem_list = 0x3
mcast, vid = 1, addr = ff:ff:ff:ff:ff:ff, port_mask = 0x1
ucast, vid = 1, addr = 74:da:ea:47:7d:9c, persistant, port_num = 0x0
mcast, vid = 1, addr = 33:33:00:00:00:01, port_mask = 0x1
mcast, vid = 1, addr = 01:00:5e:00:00:01, port_mask = 0x1
mcast, vid = 2, addr = 01:80:c2:00:00:00, port_mask = 0x1
mcast, vid = 2, addr = 01:80:c2:00:00:03, port_mask = 0x1
mcast, vid = 2, addr = 01:80:c2:00:00:0e, port_mask = 0x1
mcast, vid = 1, addr = 01:80:c2:00:00:00, port_mask = 0x1
mcast, vid = 1, addr = 01:80:c2:00:00:03, port_mask = 0x1
mcast, vid = 1, addr = 01:80:c2:00:00:0e, port_mask = 0x1
mcast, vid = 2, addr = 33:33:ff:47:7d:9d, port_mask = 0x1
mcast, vid = 1, addr = 33:33:ff:47:7d:9c, port_mask = 0x1
mcast, vid = 2, addr = 33:33:00:00:00:fb, port_mask = 0x1
mcast, vid = 2, addr = 33:33:00:01:00:03, port_mask = 0x1
mcast, vid = 1, addr = 33:33:00:00:00:fb, port_mask = 0x1
mcast, vid = 1, addr = 33:33:00:01:00:03, port_mask = 0x1
vlan , vid = 100, untag_force = 0x0, reg_mcast = 0x5, mem_list = 0x5
ucast, vid = 100, addr = 74:da:ea:47:7d:9d, persistant, port_num = 0x0
mcast, vid = 100, addr = ff:ff:ff:ff:ff:ff, port_mask = 0x1
mcast, vid = 100, addr = 33:33:00:00:00:01, port_mask = 0x1
mcast, vid = 100, addr = 01:00:5e:00:00:01, port_mask = 0x1
mcast, vid = 100, addr = 33:33:ff:47:7d:9d, port_mask = 0x1
mcast, vid = 100, addr = 01:80:c2:00:00:00, port_mask = 0x1
mcast, vid = 100, addr = 01:80:c2:00:00:03, port_mask = 0x1
mcast, vid = 100, addr = 01:80:c2:00:00:0e, port_mask = 0x1
mcast, vid = 100, addr = 33:33:00:00:00:fb, port_mask = 0x1
mcast, vid = 100, addr = 33:33:00:01:00:03, port_mask = 0x1
mcast, vid = 100, addr = 01:1b:19:00:00:00, port_mask = 0x1
			 ^^^
    Here mcast entry (ptpl2), is added only for vlan 100
    as it should be.

Based on net-next/master

v2..v1:
  net: ethernet: ti: cpsw: fix vlan mcast
	- removed limit for legacy switch cpsw mode
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The vlan configuration is not restored after interface donw/up sequence
(if dual-emac - both interfaces). Tested on am572x EVM.

Steps to check:
~# ip link add link eth1 name eth1.100 type vlan id 100
~# ifconfig eth0 down
~# ifconfig eth1 down

Try to remove vid and observe warning:
~# ip link del eth1.100
[  739.526757] net eth1: removing vlanid 100 from vlan filter
[  739.533322] failed to kill vid 0081/100 for device eth1

This patch fixes it, restoring only vlan ALE entries and all other
unicast/multicast entries are restored by system calling rx_mode ndo.
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

At this moment, mcast addresses are added for real device only
(reserved vlans for dual-emac mode), even if a mcast address was added
for some vlan only, thus ALE doesn't have corresponding vlan mcast
entries after vlan socket joined multicast group. So ALE drops vlan
frames with mcast addresses intended for vlans and potentially can
receive mcast frames for base ndev. That's not correct. So, fix it by
creating only vlan/mcast entries as requested. Patch doesn't use any
additional lists and is based on device mc address list and cpsw ALE
table entries.
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

It's redundancy for the drivers to hold the list of vlans when
absolutely the same list exists in vlan core. In most cases it's
needed only to traverse the vlan devices, their vids and sync some
settings with h/w, so add API to simplify this.

At least some of these drivers also can benefit:
grep "for_each.*vid" -r drivers/net/ethernet/

drivers/net/ethernet/hisilicon/hns3/hns3_enet.c:
drivers/net/ethernet/synopsys/dwc-xlgmac-hw.c:
drivers/net/ethernet/qlogic/qlge/qlge_main.c:
drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c:
drivers/net/ethernet/via/via-rhine.c:
drivers/net/ethernet/via/via-velocity.c:
drivers/net/ethernet/intel/igb/igb_main.c:
drivers/net/ethernet/intel/ice/ice_main.c:
drivers/net/ethernet/intel/e1000/e1000_main.c:
drivers/net/ethernet/intel/i40e/i40e_main.c:
drivers/net/ethernet/intel/e1000e/netdev.c:
drivers/net/ethernet/intel/igbvf/netdev.c:
drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c:
drivers/net/ethernet/intel/ixgb/ixgb_main.c:
drivers/net/ethernet/intel/ixgbe/ixgbe_main.c:
drivers/net/ethernet/amd/xgbe/xgbe-dev.c:
drivers/net/ethernet/emulex/benet/be_main.c:
drivers/net/ethernet/neterion/vxge/vxge-main.c:
drivers/net/ethernet/adaptec/starfire.c:
drivers/net/ethernet/brocade/bna/bnad.c:
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

In order to avoid all table update, and only remove or add new
address, the auxiliary function exists, named __hw_addr_sync_dev().
It allows end driver do nothing when nothing changed and add/rm when
concrete address is firstly added or lastly removed. But it doesn't
include cases when an address of real device or vlan was reused by
other vlans or vlan/macval devices.

For handaling events when address was reused/unreused the patch adds
new auxiliary routine - __hw_addr_ref_sync_dev(). It allows to do
nothing when nothing was changed and do updates only for an address
being added/reused/deleted/unreused. Thus, clone address changes for
vlans can be mirrored in the table. The function is exclusive with
__hw_addr_sync_dev(). It's responsibility of the end driver to
identify address vlan device, if it needs so.
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

As added in 3e59020a ("net: bql: add __netdev_tx_sent_queue()"), which
 see for performance rationale.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Michał Mirosław says:

====================
net: Remove VLAN_TAG_PRESENT from drivers

This series removes VLAN_TAG_PRESENT use from network drivers in
preparation to removing its special meaning.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Reviewed-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

This is a minimal change to allow removing of VLAN_TAG_PRESENT.
It leaves OVS unable to use CFI bit, as fixing this would need
a deeper surgery involving userspace interface.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

This just removes VLAN_TAG_PRESENT use.  VLAN TCI=0 special meaning is
deeply embedded in the driver code and so is left as is.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

return -ENOMEM directly instead of assigning it in a variable
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Current driver dynamically allocates an skb and maps it as DMA Rx
buffer. In order to prepare for upcoming XDP changes, let's introduce a
different allocation scheme.
Buffers are allocated dynamically and mapped into hardware.
During the Rx operation the driver uses build_skb() to produce the
necessary buffers for the network stack.
This change increases performance ~15% on 64b packets with smmu disabled
and ~5% with smmu enabled
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Interferences on the SPI line could distort the response of
available buffer space. So at least we should check that the
response doesn't exceed the maximum available buffer space.
In error case increase a new error counter and retry it later.
This behavior avoids buffer errors in the QCA7000, which
results in an unnecessary chip reset including packet loss.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When setting the SO_MARK socket option, if the mark changes, the dst
needs to be reset so that a new route lookup is performed.

This fixes the case where an application wants to change routing by
setting a new sk_mark.  If this is done after some packets have already
been sent, the dst is cached and has no effect.
Signed-off-by: David Barmann <david.barmann@stackpath.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Julian Wiedmann says:

====================
s390/qeth: updates 2018-11-08

please apply the following qeth patches to net-next.

The first patch allows one more device type to query the FW for a MAC address,
the others are all basically just removal of duplicated or unused code.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

qeth_l3_setup_netdev() checks if the hsuid attribute is set on the qeth
device, and propagates it to the net_device. In the past this was needed
to pick up any hsuid that was set before allocation of the net_device.

With commit d3d1b205 ("s390/qeth: allocate netdevice early") this
is no longer necessary, qeth_l3_dev_hsuid_store() always stores the
hsuid straight into dev->perm_addr.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If the CREATE ADDR sent by qeth_l3_iqd_read_initial_mac() fails, its
callback sets a random MAC address on the net_device. The error then
propagates back, and qeth_l3_setup_netdev() bails out without
registering the net_device.

Any subsequent call to qeth_l3_setup_netdev() will then attempt a fresh
CREATE ADDR which either 1) also fails, or 2) sets a proper MAC address
on the net_device. Consequently, the net_device will never be registered
with a random MAC and we can drop the fallback code.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

qeth_l3_send_ipa_arp_cmd() is merely a wrapper around
qeth_send_control_data() now. So push the length adjustment into
QETH_SETASS_BASE_LEN, and remove the wrapper. While at it, also remove
some redundant 0-initializations.

qeth_send_setassparms() requires that callers prepare their command
parameters, so that they can be copied into the parameter area in one
go. Skip the indirection, and just let callers set up the command
themselves.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Call qeth_prepare_ipa_cmd() during setup of a new IPA cmd buffer, so
that it is used for all commands. Thus ARP and SNMP requests don't have
to do their own initialization.

This will now also set the proper MPC protocol version for SNMP requests
on L2 devices.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Re-implement the card-by-RDEV lookup by using device model concepts, and
remove the now redundant list of all qeth card instances in the system.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since commit 82bf5c08 ("s390/qeth: add support for IPv6 TSO"),
qeth_xmit() also knows how to build TSO packets and is practically
identical to qeth_l3_xmit().
Convert qeth_l3_xmit() into a thin wrapper that merely strips the
L2 header off a packet, and calls qeth_xmit() for the actual
TX processing.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Filling the HW header from one single function will make it easier to
rip out all the duplicated transmit code in qeth_l3_xmit(). On top, this
saves one conditional branch in the TSO path.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

By default, READ MAC on a Layer2 OSD device returns the adapter's
burnt-in MAC address. Given the default scenario of many virtual devices
on the same adapter, qeth can't make any use of this address and
therefore skips the READ MAC call for this device type.

But in some configurations, the READ MAC command for a Layer2 OSD device
actually returns a pre-provisioned, virtual MAC address. So enable the
READ MAC code to detect this situation, and let the L2 subdriver
call READ MAC for OSD devices.

This also removes the QETH_LAYER2_MAC_READ flag, which protects L2
devices against calling READ MAC multiple times. Instead protect the
whole call to qeth_l2_request_initial_mac().
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

if local is NULL pointer, and the following access of local's
dev will trigger panic, which is same as BUG_ON
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Stefano Brivio says:

====================
ICMP error handling for UDP tunnels

This series introduces ICMP error handling for UDP tunnels and
encapsulations and related selftests. We need to handle ICMP errors to
support PMTU discovery and route redirection -- this support is entirely
missing right now:

- patch 1/11 adds a socket lookup for UDP tunnels that use, by design,
  the same destination port on both endpoints -- i.e. VXLAN and GENEVE
- patches 2/11 to 7/11 are specific to VxLAN and GENEVE
- patches 8/11 and 9/11 add infrastructure for lookup of encapsulations
  where sent packets cannot be matched via receiving socket lookup, i.e.
  FoU and GUE
- patches 10/11 and 11/11 are specific to FoU and GUE

v2: changes are listed in the single patches
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Introduce eight tests, for FoU and GUE, with IPv4 and IPv6 payload,
on IPv4 and IPv6 transport, that check that PMTU exceptions are created
with the right value when exceeding the MTU on a link of the path.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

As the destination port in FoU and GUE receiving sockets doesn't
necessarily match the remote destination port, we can't associate errors
to the encapsulating tunnels with a socket lookup -- we need to blindly
try them instead. This means we don't even know if we are handling errors
for FoU or GUE without digging into the packets.

Hence, implement a single handler for both, one for IPv4 and one for IPv6,
that will check whether the packet that generated the ICMP error used a
direct IP encapsulation or if it had a GUE header, and send the error to
the matching protocol handler, if any.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

ICMP error handling is currently not possible for UDP tunnels not
employing a receiving socket with local destination port matching the
remote one, because we have no way to look them up.

Add an err_handler tunnel encapsulation operation that can be exported by
tunnels in order to pass the error to the protocol implementing the
encapsulation. We can't easily use a lookup function as we did for VXLAN
and GENEVE, as protocol error handlers, which would be in turn called by
implementations of this new operation, handle the errors themselves,
together with the tunnel lookup.

Without a socket, we can't be sure which encapsulation error handler is
the appropriate one: encapsulation handlers (the ones for FoU and GUE
introduced in the next patch, e.g.) will need to check the new error codes
returned by protocol handlers to figure out if errors match the given
encapsulation, and, in turn, report this error back, so that we can try
all of them in __udp{4,6}_lib_err_encap_no_sk() until we have a match.

v2:
- Name all arguments in err_handler prototypes (David Miller)
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

We'll need this to handle ICMP errors for tunnels without a sending socket
(i.e. FoU and GUE). There, we might have to look up different types of IP
tunnels, registered as network protocols, before we get a match, so we
want this for the error handlers of IPPROTO_IPIP and IPPROTO_IPV6 in both
inet_protos and inet6_protos. These error codes will be used in the next
patch.

For consistency, return sensible error codes in protocol error handlers
whenever handlers can't handle errors because, even if valid, they don't
match a protocol or any of its states.

This has no effect on existing error handling paths.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use a router between endpoints, implemented via namespaces, set a low MTU
between router and destination endpoint, exceed it and check PMTU value in
route exceptions.

v2:
- Introduce IPv4 tests right away, if iproute2 doesn't support the 'df'
  link option they will be skipped (David Ahern)
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

draft-ietf-nvo3-geneve-08 says:

   It is strongly RECOMMENDED that Path MTU Discovery ([RFC1191],
   [RFC1981]) be used by setting the DF bit in the IP header when Geneve
   packets are transmitted over IPv4 (this is the default with IPv6).

Now that ICMP error handling is working for GENEVE, we can comply with
this recommendation.

Make this configurable, though, to avoid breaking existing setups. By
default, DF won't be set. It can be set or inherited from inner IPv4
packets. If it's configured to be inherited and we are encapsulating IPv6,
it will be set.

This only applies to non-lwt tunnels: if an external control plane is
used, tunnel key will still control the DF flag.

v2:
- DF behaviour configuration only applies for non-lwt tunnels, apply DF
  setting only if (!geneve->collect_md) in geneve_xmit_skb()
  (Stephen Hemminger)
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Export an encap_err_lookup() operation to match an ICMP error against a
valid VNI.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use a router between endpoints, implemented via namespaces, set a low MTU
between router and destination endpoint, exceed it and check PMTU value in
route exceptions.

v2:
- Change all occurrences of VxLAN to VXLAN (Jiri Benc)
- Introduce IPv4 tests right away, if iproute2 doesn't support the 'df'
  link option they will be skipped (David Ahern)
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Allow users to set the IPv4 DF bit in outgoing packets, or to inherit its
value from the IPv4 inner header. If the encapsulated protocol is IPv6 and
DF is configured to be inherited, always set it.

For IPv4, inheriting DF from the inner header was probably intended from
the very beginning judging by the comment to vxlan_xmit(), but it wasn't
actually implemented -- also because it would have done more harm than
good, without handling for ICMP Fragmentation Needed messages.

According to RFC 7348, "Path MTU discovery MAY be used". An expired RFC
draft, draft-saum-nvo3-pmtud-over-vxlan-05, whose purpose was to describe
PMTUD implementation, says that "is a MUST that Vxlan gateways [...]
SHOULD set the DF-bit [...]", whatever that means.

Given this background, the only sane option is probably to let the user
decide, and keep the current behaviour as default.

This only applies to non-lwt tunnels: if an external control plane is
used, tunnel key will still control the DF flag.

v2:
- DF behaviour configuration only applies for non-lwt tunnels, move DF
  setting to if (!info) block in vxlan_xmit_one() (Stephen Hemminger)
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Export an encap_err_lookup() operation to match an ICMP error against a
valid VNI.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

For both IPv4 and IPv6, if we can't match errors to a socket, try
tunnels before ignoring them. Look up a socket with the original source
and destination ports as found in the UDP packet inside the ICMP payload,
this will work for tunnels that force the same destination port for both
endpoints, i.e. VXLAN and GENEVE.

Actually, lwtunnels could break this assumption if they are configured by
an external control plane to have different destination ports on the
endpoints: in this case, we won't be able to trace ICMP messages back to
them.

For IPv6 redirect messages, call ip6_redirect() directly with the output
interface argument set to the interface we received the packet from (as
it's the very interface we should build the exception on), otherwise the
new nexthop will be rejected. There's no such need for IPv4.

Tunnels can now export an encap_err_lookup() operation that indicates a
match. Pass the packet to the lookup function, and if the tunnel driver
reports a matching association, continue with regular ICMP error handling.

v2:
- Added newline between network and transport header sets in
  __udp{4,6}_lib_err_encap() (David Miller)
- Removed redundant skb_reset_network_header(skb); in
  __udp4_lib_err_encap()
- Removed redundant reassignment of iph in __udp4_lib_err_encap()
  (Sabrina Dubroca)
- Edited comment to __udp{4,6}_lib_err_encap() to reflect the fact this
  won't work with lwtunnels configured to use asymmetric ports. By the way,
  it's VXLAN, not VxLAN (Jiri Benc)
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Trivial fix to spelling mistake in dev_err error message
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

avoid to compute the hash value if dev is not null, since
hash value is not used
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>