Alexis Bauvin says:

====================
net: Add VRF support for VXLAN underlay

v6 -> v7:
- proper locking for device in udp_tunnel following Sabrina Dubroca's advice

v5 -> v6:
- remove automatic rebinding patch following Roopa Prabhu's advice

v4 -> v5:
- move test script to its own patch (6/6)
- add schematic for test script
- apply David Ahern comments to the test script

v3 -> v4:
- rename vxlan_is_in_l3mdev_chain to netdev_is_upper master
- move it to net/core/dev.c
- make it return bool instead of int
- check if remote_ifindex is zero before resolving the l3mdev
- add testing script

v2 -> v3:
- fix build when CONFIG_NET_IPV6 is off
- fix build "unused l3mdev_master_upper_ifindex_by_index" build error with some
  configs

v1 -> v2:
- move vxlan_get_l3mdev from vxlan driver to l3mdev driver as
  l3mdev_master_upper_ifindex_by_index
- vxlan: rename variables named l3mdev_ifindex to ifindex

v0 -> v1:
- fix typos

We are trying to isolate the VXLAN traffic from different VMs with VRF as shown
in the schemas below:

+-------------------------+   +----------------------------+
| +----------+            |   |     +------------+         |
| |          |            |   |     |            |         |
| | tap-red  |            |   |     |  tap-blue  |         |
| |          |            |   |     |            |         |
| +----+-----+            |   |     +-----+------+         |
|      |                  |   |           |                |
|      |                  |   |           |                |
| +----+---+              |   |      +----+----+           |
| |        |              |   |      |         |           |
| | br-red |              |   |      | br-blue |           |
| |        |              |   |      |         |           |
| +----+---+              |   |      +----+----+           |
|      |                  |   |           |                |
|      |                  |   |           |                |
|      |                  |   |           |                |
| +----+--------+         |   |     +--------------+       |
| |             |         |   |     |              |       |
| |  vxlan-red  |         |   |     |  vxlan-blue  |       |
| |             |         |   |     |              |       |
| +------+------+         |   |     +-------+------+       |
|        |                |   |             |              |
|        |           VRF  |   |             |          VRF |
|        |           red  |   |             |         blue |
+-------------------------+   +----------------------------+
         |                                  |
         |                                  |
 +---------------------------------------------------------+
 |       |                                  |              |
 |       |                                  |              |
 |       |         +--------------+         |              |
 |       |         |              |         |              |
 |       +---------+  eth0.2030   +---------+              |
 |                 |  10.0.0.1/24 |                        |
 |                 +-----+--------+                    VRF |
 |                       |                            green|
 +---------------------------------------------------------+
                         |
                         |
                    +----+---+
                    |        |
                    |  eth0  |
                    |        |
                    +--------+

iproute2 commands to reproduce the setup:

ip link add green type vrf table 1
ip link set green up
ip link add eth0.2030 link eth0 type vlan id 2030
ip link set eth0.2030 master green
ip addr add 10.0.0.1/24 dev eth0.2030
ip link set eth0.2030 up

ip link add blue type vrf table 2
ip link set blue up
ip link add br-blue type bridge
ip link set br-blue master blue
ip link set br-blue up
ip link add vxlan-blue type vxlan id 2 local 10.0.0.1 dev eth0.2030 \
 port 4789
ip link set vxlan-blue master br-blue
ip link set vxlan-blue up
ip link set tap-blue master br-blue
ip link set tap-blue up

ip link add red type vrf table 3
ip link set red up
ip link add br-red type bridge
ip link set br-red master red
ip link set br-red up
ip link add vxlan-red type vxlan id 3 local 10.0.0.1 dev eth0.2030 \
 port 4789
ip link set vxlan-red master br-red
ip link set vxlan-red up
ip link set tap-red master br-red
ip link set tap-red up

We faced some issue in the datapath, here are the details:

* Egress traffic:
The vxlan packets are sent directly to the default VRF because it's where the
socket is bound, therefore the traffic has a default route via eth0. the
workaround is to force this traffic to VRF green with ip rules.

* Ingress traffic:
When receiving the traffic on eth0.2030 the vxlan socket is unreachable from
VRF green. The workaround is to enable *udp_l3mdev_accept* sysctl, but
this breaks isolation between overlay and underlay: packets sent from
blue or red by e.g. a guest VM will be accepted by the socket, allowing
injection of VXLAN packets from the overlay.

This patch series fixes the issues describe above by allowing VXLAN socket to be
bound to a specific VRF device therefore looking up in the correct table.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This script tests the support of a VXLAN underlay in a non-default VRF.

It does so by simulating two hypervisors and two VMs, an extended L2
between the VMs with the hypervisors as VTEPs with the underlay in a
VRF, and finally by pinging the two VMs.

It also tests that moving the underlay from a VRF to another works when
down/up the VXLAN interface.
Signed-off-by: Alexis Bauvin <abauvin@scaleway.com>
Reviewed-by: Amine Kherbouche <akherbouche@scaleway.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: Amine Kherbouche <akherbouche@scaleway.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Creating a VXLAN device with is underlay in the non-default VRF makes
egress route lookup fail or incorrect since it will resolve in the
default VRF, and ingress fail because the socket listens in the default
VRF.

This patch binds the underlying UDP tunnel socket to the l3mdev of the
lower device of the VXLAN device. This will listen in the proper VRF and
output traffic from said l3mdev, matching l3mdev routing rules and
looking up the correct routing table.

When the VXLAN device does not have a lower device, or the lower device
is in the default VRF, the socket will not be bound to any interface,
keeping the previous behaviour.

The underlay l3mdev is deduced from the VXLAN lower device
(IFLA_VXLAN_LINK).

+----------+                         +---------+
|          |                         |         |
| vrf-blue |                         | vrf-red |
|          |                         |         |
+----+-----+                         +----+----+
     |                                    |
     |                                    |
+----+-----+                         +----+----+
|          |                         |         |
| br-blue  |                         | br-red  |
|          |                         |         |
+----+-----+                         +---+-+---+
     |                                   | |
     |                             +-----+ +-----+
     |                             |             |
+----+-----+                +------+----+   +----+----+
|          |  lower device  |           |   |         |
|   eth0   | <- - - - - - - | vxlan-red |   | tap-red | (... more taps)
|          |                |           |   |         |
+----------+                +-----------+   +---------+
Signed-off-by: Alexis Bauvin <abauvin@scaleway.com>
Reviewed-by: Amine Kherbouche <akherbouche@scaleway.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: Amine Kherbouche <akherbouche@scaleway.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Existing functions to retreive the l3mdev of a device did not walk the
master chain to find the upper master. This patch adds a function to
find the l3mdev, even indirect through e.g. a bridge:

+----------+
|          |
| vrf-blue |
|          |
+----+-----+
     |
     |
+----+-----+
|          |
| br-blue  |
|          |
+----+-----+
     |
     |
+----+-----+
|          |
|   eth0   |
|          |
+----------+

This will properly resolve the l3mdev of eth0 to vrf-blue.
Signed-off-by: Alexis Bauvin <abauvin@scaleway.com>
Reviewed-by: Amine Kherbouche <akherbouche@scaleway.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: Amine Kherbouche <akherbouche@scaleway.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

UDP tunnel sockets are always opened unbound to a specific device. This
patch allow the socket to be bound on a custom device, which
incidentally makes UDP tunnels VRF-aware if binding to an l3mdev.
Signed-off-by: Alexis Bauvin <abauvin@scaleway.com>
Reviewed-by: Amine Kherbouche <akherbouche@scaleway.com>
Tested-by: Amine Kherbouche <akherbouche@scaleway.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Ido Schimmel says:

====================
mlxsw: Add 'fw_load_policy' devlink parameter

Shalom says:

Currently, drivers do not have the ability to control the firmware
loading policy and they always use their own fixed policy. This prevents
drivers from running the device with a different firmware version for
testing and/or debugging purposes. For example, testing a firmware bug
fix.

For these situations, the new devlink generic parameter,
'fw_load_policy', gives the ability to control this option and allows
drivers to run with a different firmware version than required by the
driver.

Patch #1 adds the new parameter to devlink. The other two patches, #2
and #3, add support for this parameter in the mlxsw driver.

Example:
  # Query the devlink parameters supported by the device
    $ devlink dev param show
    pci/0000:03:00.0:
      name fw_load_policy type generic
        values:
          cmode driverinit value driver

  # Flash new firmware using ethtool
    $ ethtool -f swp1 mellanox/mlxsw_spectrum-13.1703.4.mfa2

  # Toggle parameter
    $ devlink dev param set pci/0000:03:00.0 name fw_load_policy value flash cmode driverinit

  # devlink reset
    $ devlink dev reload pci/0000:03:00.0

  # Query firmware version to show changes took affect
    $ ethtool -i swp1
    driver: mlxsw_spectrum
    version: 1.0
    firmware-version: 13.1703.4
    expansion-rom-version:
    bus-info: 0000:03:00.0
    supports-statistics: yes
    supports-test: no
    supports-eeprom-access: no
    supports-register-dump: no
    supports-priv-flags: no

iproute2 patches available here:
https://github.com/tshalom/iproute2-next

v2:
* Change 'fw_version_check' to 'fw_load_policy' with values 'driver' and
  'flash' (Jakub)
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Load firmware version based on 'fw_load_policy' devlink parameter. The
driver supports these two options:
    * DEVLINK_PARAM_FW_LOAD_POLICY_VALUE_DRIVER (0)
      Default, load firmware version preferred by the driver
    * DEVLINK_PARAM_FW_LOAD_POLICY_VALUE_FLASH (1)
      Load firmware currently stored in flash

The second option, 'flash', allow the device to run with different firmware
version than preferred by the driver for testing and/or debugging purposes.
For example, testing a firmware bug fix.
Signed-off-by: Shalom Toledo <shalomt@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After flashing new firmware during the driver initialization flow (reload
or not), the driver should do a firmware reset when it gets -EAGAIN in
order to load the new one.
Signed-off-by: Shalom Toledo <shalomt@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Many drivers load the device's firmware image during the initialization
flow either from the flash or from the disk. Currently this option is not
controlled by the user and the driver decides from where to load the
firmware image.

'fw_load_policy' gives the ability to control this option which allows the
user to choose between different loading policies supported by the driver.

This parameter can be useful while testing and/or debugging the device. For
example, testing a firmware bug fix.
Signed-off-by: Shalom Toledo <shalomt@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently __set_phy_supported allows to add modes w/o checking whether
the PHY supports them. This is wrong, it should never add modes but
only remove modes we don't want to support.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Clang warns:

drivers/net/usb/aqc111.c:1326:37: warning: suggest braces around
initialization of subobject [-Wmissing-braces]
                struct aqc111_wol_cfg wol_cfg = { 0 };
                                                  ^
                                                  {}
1 warning generated.

Use memset to initialize the object to take compiler instrumentation out
of the equation.

Fixes: e58ba454 ("net: usb: aqc111: Add support for wake on LAN by MAGIC packet")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/net/ethernet/qualcomm/rmnet/rmnet_map_command.c: In function 'rmnet_map_do_flow_control':
drivers/net/ethernet/qualcomm/rmnet/rmnet_map_command.c:23:36: warning:
 variable 'cmd' set but not used [-Wunused-but-set-variable]
  struct rmnet_map_control_command *cmd;

'cmd' not used anymore now, should also be removed.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

The userspace may need to control the carrier state.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Didier Pallard <didier.pallard@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

the flowi* structures are used and memsetted by server functions
in critical path. Currently flowi_common has a couple of holes that
we can eliminate reordering the struct fields. As a side effect,
both flowi4 and flowi6 shrink by 8 bytes.

Before:
pahole -EC flowi_common
struct flowi_common {
// ...
	/* size: 40, cachelines: 1, members: 10 */
	/* sum members: 32, holes: 1, sum holes: 4 */
	/* padding: 4 */
	/* last cacheline: 40 bytes */
};
pahole -EC flowi6
struct flowi6 {
// ...
        /* size: 88, cachelines: 2, members: 6 */
        /* padding: 4 */
        /* last cacheline: 24 bytes */
};
pahole -EC flowi4
struct flowi4 {
// ...
        /* size: 56, cachelines: 1, members: 4 */
        /* padding: 4 */
        /* last cacheline: 56 bytes */
};

After:
struct flowi_common {
// ...
	/* size: 32, cachelines: 1, members: 10 */
	/* last cacheline: 32 bytes */
};
struct flowi6 {
// ...
        /* size: 80, cachelines: 2, members: 6 */
        /* padding: 4 */
        /* last cacheline: 16 bytes */
};
struct flowi4 {
// ...
        /* size: 48, cachelines: 1, members: 4 */
        /* padding: 4 */
        /* last cacheline: 48 bytes */
};
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Ido Schimmel says:

====================
mlxsw: Add VxLAN support with VLAN-aware bridges

Commit 53e50a6e ("Merge branch 'mlxsw-Add-VxLAN-support'") added
mlxsw support for VxLAN when the VxLAN device was enslaved to
VLAN-unaware bridges. This patchset extends mlxsw to also support VxLAN
with VLAN-aware bridges.

With VLAN-aware bridges, the VxLAN device's VNI is mapped to the VLAN
that is configured as 'pvid untagged' on the corresponding bridge port.
To prevent ambiguity, mlxsw forbids configurations in which the same
VLAN is configured as 'pvid untagged' on multiple VxLAN devices.

Patches #1-#2 add the necessary APIs in mlxsw and the bridge driver.

Patches #3-#4 perform small refactoring in order to prepare mlxsw for
VLAN-aware support.

Patch #5 finally enables the enslavement of VxLAN devices to a
VLAN-aware bridge. Among other things, it extends mlxsw to handle
switchdev notifications about VLAN add / delete on a VxLAN device
enslaved to an offloaded VLAN-aware bridge.

Patches #6-#8 add selftests to test the new functionality.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The test is very similar to its VLAN-unaware counterpart
(vxlan_bridge_1d.sh), but instead of using multiple VLAN-unaware
bridges, a single VLAN-aware bridge is used with multiple VLANs.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Extend the existing VLAN-unaware tests with their VLAN-aware
counterparts. This includes sanitization of invalid configuration and
offload indication on the local route performing decapsulation and the
FDB entries perform encapsulation.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Previous patches add the ability to work with VLAN-aware bridges and
VxLAN devices, so make sure such configuration no longer fails.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 1c30d183 ("mlxsw: spectrum: Enable VxLAN enslavement to
bridges") enabled the enslavement of VxLAN devices to bridges that have
mlxsw ports (or their upper) as slaves. This patch extends mlxsw to also
support VLAN-aware bridges.

The patch is similar in nature to mentioned commit, but there is one
major difference. With VLAN-aware bridges, the VxLAN device's VNI is
mapped to the VLAN that is configured as PVID and egress untagged on the
bridge port.

Therefore, the driver is extended to listen to VLAN configuration on
VxLAN devices of interest and enable / disable NVE encapsulation on the
corresponding 802.1Q FIDs.

To prevent ambiguity, the driver makes sure that a given VLAN is not
configured as PVID and egress untagged on multiple VxLAN devices. This
sanitization takes place both when a port is enslaved to a bridge with
existing VxLAN devices and when a VLAN is added to / removed from a
VxLAN device of interest.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The vxlan_join() function resolves the FID on which the VNI should be
set and then sets the VNI. Currently, the FID is simply resolved
according to the ifindex of the bridge device to which the VxLAN device
is enslaved. This works because only VLAN-unaware bridges are supported.

With VLAN-aware bridges the FID would need to be resolved based on the
VLAN to which the VNI is mapped to.

Add the VLAN ID to the argument list of the function.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The function mlxsw_sp_bridge_vxlan_leave() is currently split between
VLAN-aware and VLAN-unaware bridges, but actually both types can use the
same function.

The function needs to resolve the FID that corresponds to the VxLAN
device and disable NVE encapsulation on it. Instead of looking up the
FID differently for VLAN-aware and VLAN-unaware bridges, we can always
use the VxLAN's device VNI.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In a similar fashion to commit 564c6d72 ("mlxsw: spectrum_fid: Add
APIs to lookup FID without creating it"), add a corresponding API to
lookup 802.1Q FIDs.

This is a prerequisite to VxLAN support with VLAN-aware bridges and will
allow us to resolve a 802.1Q FID by its VLAN when an FDB entry is added
on the bridge port of the VxLAN device.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, the function only works for the bridge device itself, but
subsequent patches will need to be able to query the PVID of a given
bridge port, so extend the function.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Ariel Elior says:

====================
qed*: Doorbell overflow recovery

Doorbell Overflow
If sufficient CPU cores will send doorbells at a sufficiently high rate, they
can cause an overflow in the doorbell queue block message fifo. When fill level
reaches maximum, the device stops accepting all doorbells from that PF until a
recovery procedure has taken place.

Doorbell Overflow Recovery
The recovery procedure basically means resending the last doorbell for every
doorbelling entity. A doorbelling entity is anything which may send doorbells:
L2 tx ring, rdma sq/rq/cq, light l2, vf l2 tx ring, spq, etc. This relies on
the design assumption that all doorbells are aggregative, so last doorbell
carries the information of all previous doorbells.

APIs
All doorbelling entities need to register with the mechanism before sending
doorbells. The registration entails providing the doorbell address the entity
would be using, and a virtual address where last doorbell data can be found.
Typically fastpath structures already have this construct.

Executing the recovery procedure
Handling the attentions, iterating over all the registered entities and
resending their doorbells, is all handled within qed core module.

Relevance
All doorbelling entities in all protocols need to register with the mechanism,
via the new APIs. Technically this is quite simple (just call the API). Some
protocol fastpath implementation may not have the doorbell data stored anywhere
(compute it from scratch every time) and will have to add such a place.
This is rare and is also better practice (save some cycles on the fastpath).

Performance Penalty
No performance penalty should incur as a result of this feature. If anything
performance can improve by avoiding recalcualtion of doorbell data everytime
doorbell is sent (in some flows).

Add the database used to register doorbelling entities, and APIs for adding
and deleting entries, and logic for traversing the database and doorbelling
once on behalf of all entities.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

All L2 queues funnel through this flow, so this would cover the
regular RSS queues, as well queues created for VFs, mqos queues,
xdp queues, etc.
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Most of the doorbelling entities are outside of the core module.
L2 queues, Roce queues, iscsi and fcoe all need to register.
Make the APIs available for these drivers.
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Light L2 queues are doorbelling entities. Modify the implementation
to keep the doorbell data necessary for doorbelling in well known
location instead of recomputing every time. Register the LL2 queue
with doorbell recovery mechanism.
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Slow path queue is a doorbelling entity. Register it with the overflow mechanism.
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In case of an attention from the doorbell queue block, analyze the HW
indications. In case of a doorbell overflow, execute a doorbell recovery.
Since there can be spurious indications (race conditions between multiple PFs),
schedule a periodic task for checking whether a doorbell overflow may have been
missed. After a set time with no indications, terminate the periodic task.
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add the database used to register doorbelling entities, and APIs for adding
and deleting entries, and logic for traversing the database and doorbelling
once on behalf of all entities.
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jakub Kicinski says:

====================
rtnetlink: avoid a warning in rtnl_newlink()

I've been hoping for some time that someone more competent would fix
the stack frame size warning in rtnl_newlink(), but looks like I'll
have to take a stab at it myself :)  That's the only warning I see
in most of my builds.

First patch refactors away a somewhat surprising if (1) code block.
Reindentation will most likely cause cherry-pick problems but OTOH
rtnl_newlink() doesn't seem to be changed often, so perhaps we can
risk it in the name of cleaner code?

Second patch fixes the warning in simplest possible way.  I was
pondering if there is any more clever solution, but I can't see it..
rtnl_newlink() is quite long with a lot of possible execution paths
so doing memory allocations half way through leads to very ugly
results.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Standard kernel compilation produces the following warning:

net/core/rtnetlink.c: In function ‘rtnl_newlink’:
net/core/rtnetlink.c:3232:1: warning: the frame size of 1288 bytes is larger than 1024 bytes [-Wframe-larger-than=]
 }
  ^

This should not really be an issue, as rtnl_newlink() stack is
generally quite shallow.

Fix the warning by allocating attributes with kmalloc() in a wrapper
and passing it down to rtnl_newlink(), avoiding complexities on error
paths.

Alternatively we could kmalloc() some structure within rtnl_newlink(),
slave attributes look like a good candidate.  In practice it adds to
already rather high complexity and length of the function.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnl_newlink() used to create VLAs based on link kind.  Since
commit ccf8dbcd ("rtnetlink: Remove VLA usage") statically
sized array is created on the stack, so there is no more use
for a separate code block that used to be the VLA's live range.

While at it christmas tree the variables.  Note that there is
a goto-based retry so to be on the safe side the variables can
no longer be initialized in place.  It doesn't seem to matter,
logically, but why make the code harder to read..
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jakub Kicinski says:

====================
nfp: update TX path to enable repr offloads

This set starts with three micro optimizations to the TX path.
The improvement is measurable, but below 1% of CPU utilization.

Patches 4 - 9 add basic TX offloads to representor devices, like
checksum offload or TSO, and remove the unnecessary TX lock and
Qdisc (our representors are software constructs on top of the PF).

The last 2 patches add more info to error messages - id of command
which failed and exact location of incorrect TLVs, very useful for
debugging.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

FW reconfiguration timeouts are a common indicator of FW trouble.
To make debugging easier print requested update and control word
when reconfiguration fails.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When troubleshooting incorrect FW capabilities it's useful to know
where the faulty TLV is located.  Add offset to all errors messages.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

FW/HW can generally support the standard networking offloads
on representors without any trouble.  Add the ability for FW
to advertise which features should be available on representors.

Because representors are muxed on top of the vNIC we need to listen
on feature changes of their lower devices, and update their features
appropriately.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Up until now we never needed to keep a networking locks around
representors accesses, we only accessed them when device was
reconfigured (under nfp pf->lock) or on fast path (under RCU).
Now we want to be able to iterate over all representors during
notifications, so make sure representor assignment is done
under RTNL lock.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Our representors are software devices built on top of the PF
vNIC, the queuing should only happen at the vNIC netdevice.
Allow representors to run qdisc-less.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Our representors are software devices built on top of the PF
vNIC, the only state they have are per-cpu stats, so make
the TX run locklessly.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>