genetlink: use attrs from struct genl_info

Since dumps carry struct genl_info now, use the attrs pointer
from genl_info and remove the one in struct genl_dumpit_info.

Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20230814214723.2924989-6-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: convert some netlink netdev iterators to depend on the xarray

Reap the benefits of easier iteration thanks to the xarray.
Convert just the genetlink ones, those are easier to test.

Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20230726185530.2247698-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ethtool: tunnels: check the return value of nla_nest_start()

Check the return value of nla_nest_start(). When starting the entry
level nested attributes, if the tailroom of socket buffer is
insufficient to store the attribute header and payload, the return value
will be NULL.

There is, however, no real bug here since if the skb is full
nla_put_be16() will fail as well and we'll error out.

Signed-off-by: Li Zhong <floridsleeves@gmail.com>
Link: https://lore.kernel.org/r/20220921181716.1629541-1-floridsleeves@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ethtool: use ethnl_parse_header_dev_put()

It seems I missed that most ethnl_parse_header_dev_get() callers
declare an on-stack struct ethnl_req_info, and that they simply call
dev_put(req_info.dev) when about to return.

Add ethnl_parse_header_dev_put() helper to properly untrack
reference taken by ethnl_parse_header_dev_get().

Fixes: e4b8954074f6 ("netlink: add net device refcount tracker to struct ethnl_req_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ethtool: link up ethnl_header_policy as a nested policy

To get the most out of parsing by the core, and to allow dumping
full policies we need to specify which policy applies to nested
attrs. For headers it's ethnl_header_policy.

$ sed -i 's@\(ETHTOOL_A_.*HEADER\].*=\) { .type = NLA_NESTED },@\1\n\t\tNLA_POLICY_NESTED(ethnl_header_policy),@' net/ethtool/*

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

ethtool: trim policy tables

Since ethtool uses strict attribute validation there's no need
to initialize all attributes in policy tables. 0 is NLA_UNSPEC
which is going to be rejected. Remove the NLA_REJECTs.

Similarly attributes above maxattrs are rejected, so there's
no need to always size the policy tables to ETHTOOL_A_..._MAX.

v2: - new patch

Suggested-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

ethtool: wire up get policies to ops

Wire up policies for get commands in struct nla_policy of the ethtool
family. Make use of genetlink code attr validation and parsing, as well
as allow dumping policies to user space.

For every ETHTOOL_MSG_*_GET:
- add 'ethnl_' prefix to policy name
- add extern declaration in net/ethtool/netlink.h
- wire up the policy & attr in ethtool_genl_ops[].
- remove .request_policy and .max_attr from ethnl_request_ops.

Obviously core only records the first "layer" of parsed attrs
so we still need to parse the sub-attrs of the nested header
attribute.

v2:
- merge of patches 1 and 2 from v1
- remove stray empty lines in ops
- also remove .max_attr

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

ethtool: add and use message type for tunnel info reply

Tunnel offload info code uses ETHTOOL_MSG_TUNNEL_INFO_GET message type (cmd
field in genetlink header) for replies to tunnel info netlink request, i.e.
the same value as the request have. This is a problem because we are using
two separate enums for userspace to kernel and kernel to userspace message
types so that this ETHTOOL_MSG_TUNNEL_INFO_GET (28) collides with
ETHTOOL_MSG_CABLE_TEST_TDR_NTF which is what message type 28 means for
kernel to userspace messages.

As the tunnel info request reached mainline in 5.9 merge window, we should
still be able to fix the reply message type without breaking backward
compatibility.

Fixes: c7d759eb7b12 ("ethtool: add tunnel info interface")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

udp_tunnel: add the ability to hard-code IANA VXLAN

mlx5 has the IANA VXLAN port (4789) hard coded by the device,
instead of being added dynamically when tunnels are created.

To support this add a workaround flag to struct udp_tunnel_nic_info.
Skipping updates for the port is fairly trivial, dumping the hard
coded port via ethtool requires some code duplication. The port
is not a part of any real table, we dump it in a special table
which has no tunnel types supported and only one entry.

This is the last known workaround / hack needed to convert
all drivers to the new infra.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

ethtool: add tunnel info interface

Add an interface to report offloaded UDP ports via ethtool netlink.

Now that core takes care of tracking which UDP tunnel ports the NICs
are aware of we can quite easily export this information out to
user space.

The responsibility of writing the netlink dumps is split between
ethtool code and udp_tunnel_nic.c - since udp_tunnel module may
not always be loaded, yet we should always report the capabilities
of the NIC.

$ ethtool --show-tunnels eth0
Tunnel information for eth0:
UDP port table 0:
Size: 4
Types: vxlan
No entries
UDP port table 1:
Size: 4
Types: geneve, vxlan-gpe
Entries (1):
port 1230, vxlan-gpe

v4:
- back to v2, build fix is now directly in udp_tunnel.h
v3:
- don't compile ETHTOOL_MSG_TUNNEL_INFO_GET in if CONFIG_INET
not set.
v2:
- fix string set count,
- reorder enums in the uAPI,
- fix type of ETHTOOL_A_TUNNEL_UDP_TABLE_TYPES to bitset
in docs and comments.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>