mlxsw: spectrum_ipip: Add Spectrum-1 ip6gre support

As explained in the previous patch, the existing Spectrum-2 ip6gre
implementation can be reused for Spectrum-1. Change the Spectrum-1
ip6gre operations structure to use the common operations.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxsw: spectrum_ipip: Rename Spectrum-2 ip6gre operations

There are two main differences between Spectrum-1 and newer ASICs in
terms of IP-in-IP support:

1. In Spectrum-1, RIFs representing ip6gre tunnels require two entries
in the RIF table.

2. In Spectrum-2 and newer ASICs, packets ingress the underlay (during
encapsulation) and egress the underlay (during decapsulation) via a
special generic loopback RIF.

The first difference was handled in previous patches by adding the
'double_rif_entry' field to the Spectrum-1 operations structure of
ip6gre RIFs. The second difference is handled during RIF creation, by
only creating a generic loopback RIF in Spectrum-2 and newer ASICs.

Therefore, the ip6gre operations can be shared between Spectrum-1 and
newer ASIC in a similar fashion to how the ipgre operations are shared.

Rename the operations to not be Spectrum-2 specific and move them
earlier in the file so that they could later be used for Spectrum-1.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxsw: spectrum_router: Add support for double entry RIFs

In Spectrum-1, loopback router interfaces (RIFs) used for IP-in-IP
encapsulation with an IPv6 underlay require two RIF entries and the RIF
index must be even.

Prepare for this change by extending the RIF parameters structure with a
'double_entry' field that indicates if the RIF being created requires
two RIF entries or not. Only set it for RIFs representing ip6gre tunnels
in Spectrum-1.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxsw: Avoid warning during ip6gre device removal

IPv6 addresses which are used for tunnels are stored in a hash table
with reference counting. When a new GRE tunnel is configured, the driver
is notified and configures it in hardware.

Currently, any change in the tunnel is not applied in the driver. It
means that if the remote address is changed, the driver is not aware of
this change and the first address will be used.

This behavior results in a warning [1] in scenarios such as the
following:

# ip link add name gre1 type ip6gre local 2000::3 remote 2000::fffe tos inherit ttl inherit
# ip link set name gre1 type ip6gre local 2000::3 remote 2000::ffff ttl inherit
# ip link delete gre1

The change of the address is not applied in the driver. Currently, the
driver uses the remote address which is stored in the 'parms' of the
overlay device. When the tunnel is removed, the new IPv6 address is
used, the driver tries to release it, but as it is not aware of the
change, this address is not configured and it warns about releasing non
existing IPv6 address.

Fix it by using the IPv6 address which is cached in the IPIP entry, this
address is the last one that the driver used, so even in cases such the
above, the first address will be released, without any warning.

[1]:

WARNING: CPU: 1 PID: 2197 at drivers/net/ethernet/mellanox/mlxsw/spectrum.c:2920 mlxsw_sp_ipv6_addr_put+0x146/0x220 [mlxsw_spectrum]
...
CPU: 1 PID: 2197 Comm: ip Not tainted 5.17.0-rc8-custom-95062-gc1e5ded51a9a #84
Hardware name: Mellanox Technologies Ltd. MSN4700/VMOD0010, BIOS 5.11 07/12/2021
RIP: 0010:mlxsw_sp_ipv6_addr_put+0x146/0x220 [mlxsw_spectrum]
...
Call Trace:
<TASK>
mlxsw_sp2_ipip_rem_addr_unset_gre6+0xf1/0x120 [mlxsw_spectrum]
mlxsw_sp_netdevice_ipip_ol_event+0xdb/0x640 [mlxsw_spectrum]
mlxsw_sp_netdevice_event+0xc4/0x850 [mlxsw_spectrum]
raw_notifier_call_chain+0x3c/0x50
call_netdevice_notifiers_info+0x2f/0x80
unregister_netdevice_many+0x311/0x6d0
rtnl_dellink+0x136/0x360
rtnetlink_rcv_msg+0x12f/0x380
netlink_rcv_skb+0x49/0xf0
netlink_unicast+0x233/0x340
netlink_sendmsg+0x202/0x440
____sys_sendmsg+0x1f3/0x220
___sys_sendmsg+0x70/0xb0
__sys_sendmsg+0x54/0xa0
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: e846efe2737b ("mlxsw: spectrum: Add hash table for IPv6 address mapping")
Reported-by: Maksym Yaremchuk <maksymy@nvidia.com>
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20220511115747.238602-1-idosch@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

mlxsw: spectrum_ipip: Use common hash table for IPv6 address mapping

Use the common hash table introduced by the previous patch instead of
the IP-in-IP specific implementation.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: Add support for IP-in-IP with IPv6 underlay for Spectrum-2 and above

Currently, mlxsw driver supports IP-in-IP only with IPv4 underlay.
Add support for IPv6 underlay for Spectrum-2 and above.

Most of the configurations are same to IPv4, the main difference between
IPv4 and IPv6 is related to saving IP addresses.
IPv6 addresses are saved as part of KVD and the relevant registers hold
pointer to them.
Add API for that as part of ipip_ops, so then only Spectrum-2 and above
will save IPv6 addresses in this way.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_router: Increase parsing depth for IPv6 decapsulation

The Spectrum ASIC has a configurable limit on how deep into the packet
it parses. By default, the limit is 96 bytes.

For IP-in-IP packets, with IPv6 outer and inner headers, the default
parsing depth is not enough and without increasing it such packets cannot
be properly decapsulated.

Use the existing API to set parsing depth, call it once for each
decapsulation entry when it is created/destroyed.
There is no need to protect the code with new mutex because 'router->lock'
is already taken in these code paths.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_ipip: Add mlxsw_sp_ipip_gre6_ops

Add operations for IP-in-IP GRE6. For now the function can_offload()
returns false and the other functions warn as they should never be called.

A later patch will add dedicated operations for Spectrum-2 which will
support IPv6 underlay, so use 'mlxsw_sp1_' prefix for the new operations.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: Create separate ipip_ops_arr for different ASICs

Currently, there is support for IP-in-IP only with IPv4 underlay for all
supported Spectrum ASICs.
The next patches will add support for IPv6 underlay only for Spectrum-2
and above.

Add infrastructure for splitting IP-in-IP support between different
ASICs - create separate ipip_ops_arr and add ipips_init function to set the
right ops.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: Take tunnel's type into account when searching underlay device

The function __mlxsw_sp_ipip_netdev_ul_dev_get() returns the underlay
device that corresponds to the overlay device that it gets.
Currently, this function assumes that the tunnel is IPv4 GRE, because it
is the only one that is supported by mlxsw driver.

This assumption will no longer be correct when IPv6 GRE support is added,
resulting in wrong underlay device being returned.
Instead, check 'ol_dev->type' and return the underlay device accordingly.

Move the function to spectrum_ipip.c because spectrum_router.c should not
be aware to tunnel type.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_ipip: Create common function for mlxsw_sp_ipip_ol_netdev_change_gre()

The function mlxsw_sp_ipip_ol_netdev_change_gre4() contains code that
can be shared between IPv4 and IPv6.
The only difference is the way that arguments are taken from tunnel
parameters, which are different between IPv4 and IPv6.

For that, add structure 'mlxsw_sp_ipip_parms' to hold all the required
parameters for the function and save it as part of
'struct mlxsw_sp_ipip_entry' instead of the existing structure that is
not shared between IPv4 and IPv6. Add new operation as part of
'mlxsw_sp_ipip_ops' to initialize the new structure.

Then mlxsw_sp_ipip_ol_netdev_change_gre{4,6}() will prepare the new
structure and both will call the same function.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_ipip: Pass IP tunnel parameters by reference and as 'const'

Currently, there are several functions that handle 'struct ip_tunnel_parm'
and 'struct __ip6_tnl_parm'.

Change the mentioned functions to get IP tunnel parameters by reference
and as 'const'.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_router: Pass payload pointer to nexthop update function

Have the caller pass a pointer to the payload of the RATR register to
the function updating a single nexthop / adjacency entry.

In a subsequent patch, this will allow the caller to make sure
replacement was successful by querying the state of the adjacency entry
after replacement and comparing with the initial request.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_router: Add ability to overwrite adjacency entry only when inactive

Allow the driver to instruct the device to only overwrite an adjacency
entry if its activity is cleared. Currently, adjacency entry is always
overwritten, regardless of activity.

This will be used by subsequent patches to prevent replacement of active
nexthop buckets.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum: Fix ECN marking in tunnel decapsulation

Cited commit changed the behavior of the software data path with regards
to the ECN marking of decapsulated packets. However, the commit did not
change other callers of __INET_ECN_decapsulate(), namely mlxsw. The
driver is using the function in order to ensure that the hardware and
software data paths act the same with regards to the ECN marking of
decapsulated packets.

The discrepancy was uncovered by commit 5aa3c334a449 ("selftests:
forwarding: vxlan_bridge_1d: Fix vxlan ecn decapsulate value") that
aligned the selftest to the new behavior. Without this patch the
selftest passes when used with veth pairs, but fails when used with
mlxsw netdevs.

Fix this by instructing the device to propagate the ECT(1) mark from the
outer header to the inner header when the inner header is ECT(0), for
both NVE and IP-in-IP tunnels.

A helper is added in order not to duplicate the code between both tunnel
types.

Fixes: b723748750ec ("tunnel: Propagate ECT(1) when decapsulating as recommended by RFC6040")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_router: Reduce mlxsw_sp_ipip_fib_entry_op_gre4()

Turned out that mlxsw_sp_ipip_fib_entry_op_gre4() does not need to
figure out the IP address and virtual router id. Those are exactly
the same as in the fib_entry it is called for. So just use that and
reduce mlxsw_sp_ipip_fib_entry_op_gre4() function to only call
mlxsw_sp_ipip_fib_entry_op_gre4_rtdp() make the ipip decap op
code similar to nve.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_ipip: Remove overlay protocol from can_offload() callback

The overlay protocol (i.e., IPv4/IPv6) that is being encapsulated has
no impact on whether a certain IP tunnel can be offloaded or not. Only
the underlay protocol matters.

Therefore, remove the unused overlay protocol parameter from the
callback.

This will later allow us to consolidate code paths between IPv4 and IPv6
code.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxsw: spectrum_router: Introduce fib_entry priv for low-level ops

Prepare for the low-level ops that need to store some data alongside
the fib_entry and introduce a per-fib_entry priv for ll ops.
The priv is reference counted as in the follow-up patch it is going
to be saved in pack() function and used later on in commit() even in
case the related fib_entry gets freed in the middle.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxsw: spectrum: Push RALUE packing and writing into low-level router ops

With follow-up introduction of XM implementation, XMDR register is
going to be optionally used instead of RALUE register. Push the RALUE
packing helpers and write call into low-level router ops.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxsw: spectrum: Export RALUE pack helper and use it from IPIP

As the RALUE packing is going to be put into op, make the user from
IPIP code use the same helper as the router code does.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxsw: spectrum: Propagate context from work handler containing RALUE payload

Currently, RALUE payload is defined locally in the function that is
calling the register write. With introduction of alternative register to
RALUE, XMDR, it has to be possible to put multiple FIB entry
operations into single register write.

So in order to prepare for that, have per-work entry operation context
and propagate it all the way down to the functions writing RALUE.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxsw: spectrum_router: Use RALUE-independent op arg

Since the write/delete of FIB entry is going to be implemented by XMDR
register for XM implementation, introduce RALUE-independent enum for op
so the enum could be used in both RALUE and XMDR.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxsw: Add ECN configurations with IPinIP tunnels

Initialize ECN mapping registers during router init according to
INET_ECN_encapsulate() and INET_ECN_decapsulate().

For IP-in-IP encapsulation, this is required to ensure that ECN bits in
the underlay are set in accordance with the kernel. For decapsulation,
this is required to ensure that packets with invalid ECN combination in
underlay and overlay are trapped to the kernel and not forwarded.

Signed-off-by: Amit Cohen <amitc@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_router: Update tunnel decap properties

Spectrum-2 requires to specify the egress RIF when setting tunnel decap
properties. Add a method for accessing the underlay RIF index and then use
it when setting decap properties.

Signed-off-by: Nir Dotan <nird@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: Replace license text with SPDX identifiers and adjust copyrights

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_ipip: Support decoding IPv6 tunnel addresses

To support mirroring to ip6gretap, the SPAN module needs to be able to
decode IPv6 addresses specified at that tunnel.

Extend mlxsw_sp_ipip_netdev_saddr() and mlxsw_sp_ipip_netdev_daddr() to
support IPv6 addresses. To that end, add and publish a support function
mlxsw_sp_ipip_netdev_parms6().

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_ipip: Extract mlxsw_sp_l3addr_is_zero

Extract the logic for determining whether a given IPv4/IPv6 address is
all-zeroes from mlxsw_sp_ipip_tunnel_complete to a separate function.
Make that function public within the module.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum: Distinguish between IPv4/6 tunnels

struct ip_tunnel_parm, where GRE and several other tunnel types hold
information, is IPv4-specific. The current router / ipip code in mlxsw
however uses it as if it were generic.

Make it clear that it's not. Rename many functions from _params_ to
_params4_. mlxsw_sp_ipip_parms_saddr() and _daddr() take a proto
argument to dispatch on it. Move the dispatch logic to
mlxsw_sp_ipip_netdev_saddr() and _daddr(), and replace with
single-protocol functions.

In struct mlxsw_sp_ipip_entry, move the "parms" field to a (for the time
being, singleton) union. Update users throughout.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_ipip: Handle underlay device change

When a bound device of an IP-in-IP tunnel changes, such as through
'ip tunnel change name $name dev $dev', the loopback backing the tunnel
needs to be recreated.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum: Handle NETDEV_CHANGE on L3 tunnels

Changes to L3 tunnel netdevices (through `ip tunnel change' as well as
`ip link set') lead to NETDEV_CHANGE being generated on the tunnel
device. Because what is relevant for the tunnel in question depends on
the tunnel type, handling of the event is dispatched to the IPIP module
through a newly-added interface mlxsw_sp_ipip_ops.ol_netdev_change().

IPIP tunnels now remember the last set of tunnel parameters in struct
mlxsw_sp_ipip_entry.parms, and use it to figure out what exactly has
changed.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_ipip: Split accessor functions

To implement NETDEV_CHANGE notifications on IP-in-IP tunnels, the
handler needs to figure out what actually changed, to understand how
exactly to update the offloads. It will do so by storing struct
ip_tunnel_parm with previous configuration, and comparing that to the
new version.

To facilitate these comparisons, extract the code that operates on
struct ip_tunnel_parm from the existing accessor functions, and make
those a thin wrapper that extracts tunnel parameters and dispatches.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum: Move mlxsw_sp_ipip_netdev_{s, d}addr{, 4}()

These functions ideologically belong to the IPIP module, and some
follow-up work will benefit from their presence there.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_router: Support GRE tunnels

This patch introduces callbacks and tunnel type to offload GRE tunnels.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_router: Add mlxsw_sp_ipip_ops

Details of individual tunnel types are kept in an array of
mlxsw_sp_ipip_ops objects. Follow-up patches will use the list to
determine whether a constructed RIF should be a loopback, and to decide
whether a next hop references a tunnel.

The list is currently empty, follow-up patches will add support for GRE.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>