net/mlx5: Lag, Use mlx5_lag_dev() instead of derefering pointers

Use the existing wrapper mlx5_lag_dev() to access the lag object from
dev for better maintainability and consistent code.

Signed-off-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5: Lag, correct get the port select mode str

mode & mode_flags is updated at the end of mlx5_activate_lag which
may not reflect the actual mode as shown in below logic:
mlx5_activate_lag(struct mlx5_lag *ldev,
|-- unsigned long flags = 0;
|-- err = mlx5_lag_set_flags(ldev, mode, tracker, shared_fdb, &flags);
|-- err = mlx5_create_lag(ldev, tracker, mode, flags);
|-- mlx5_get_str_port_sel_mode(ldev);
|-- ldev->mode = mode;
|-- ldev->mode_flags = flags;
Use mode & flag as parameters to get port select mode info.

Fixes: 94db33177819 ("net/mlx5: Support multiport eswitch mode")
Signed-off-by: Liu, Changcheng <jerrliu@nvidia.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5: Lag, decouple FDB selection and shared FDB

Multiport eswitch is required to use native FDB selection instead of
affinity, This was achieved by passing the shared_fdb flag down
the HW lag creation path. While it did accomplish the goal of setting
FDB selection mode to native, it had the side effect of also
creating a shared FDB configuration.

This created a few issues:
- TC rules are inserted into a non active FDB, which means traffic isn't
offloaded as all traffic will reach only a single FDB.
- All wire traffic is treated as if a single physical port received it; while
this is true for a bond configuration, this shouldn't be the case for
multiport eswitch.

Create a new flag MLX5_LAG_MODE_FLAG_FDB_SEL_MODE_NATIVE
to indicate what FDB selection mode should be used.

Fixes: 94db33177819 ("net/mlx5: Support multiport eswitch mode")
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5: Support multiport eswitch mode

Multiport eswitch mode is a LAG mode that allows to add rules that
forward traffic to a specific physical port without being affected by LAG
affinity configuration.

This mode of operation is mutual exclusive with the other LAG modes used
by multipath and bonding.

To make the transition between the modes, we maintain a counter on the
number of rules specifying one of the uplink representors as the target
of mirred egress redirect action.

An example of such rule would be:

$ tc filter add dev enp8s0f0_0 prot all root flower dst_mac \
00:11:22:33:44:55 action mirred egress redirect dev enp8s0f0

If the reference count just grows to one and LAG is not in use, we
create the LAG in multiport eswitch mode. Other mode changes are not
allowed while in this mode. When the reference count reaches zero, we
destroy the LAG and let other modes be used if needed.

logic also changed such that if forwarding to some uplink destination
cannot be guaranteed, we fail the operation so the rule will eventually
be in software and not in hardware.

Signed-off-by: Eli Cohen <elic@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5: Lag, refactor lag state machine

LAG state machine is implemented using bit flags. However, all these bit
flags, except for MLX5_LAG_FLAG_HASH_BASED, are really mutual exclusive.

In addition, MLX5_LAG_FLAG_READY is used by bonding to mark if we have
our netdevices successfully added to lag and does not really belong in
the same flags variable as the other flags.

Rename MLX5_LAG_FLAG_READY to MLX5_LAG_FLAG_NDEVS_READY to better
reflect its purpose and put it in a new flags variable.

For the rest of the flags, we introduce a mode enum to hold the state
of the LAG.

Remove the shared fdb boolean flag from struct mlx5_lag and store this
configuration as a mode flag.

Change all flag related operations to use standard Linux APIs.

Signed-off-by: Eli Cohen <elic@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5: Lag, add debugfs to query hardware lag state

Lag state has become very complicated with many modes, flags, types and
port selections methods and future work will add additional features.

Add a debugfs to query the current lag state. A new directory named "lag"
will be created under the mlx5 debugfs directory. As the driver has
debugfs per pci function the location will be: <debugfs>/mlx5/<BDF>/lag

For example:
/sys/kernel/debug/mlx5/0000:08:00.0/lag

The following files are exposed:

- state: Returns "active" or "disabled". If "active" it means hardware
lag is active.

- members: Returns the BDFs of all the members of lag object.

- type: Returns the type of the lag currently configured. Valid only
if hardware lag is active.
* "roce" - Members are bare metal PFs.
* "switchdev" - Members are in switchdev mode.
* "multipath" - ECMP offloads.

- port_sel_mode: Returns the egress port selection method, valid
only if hardware lag is active.
* "queue_affinity" - Egress port is selected by
the QP/SQ affinity.
* "hash" - Egress port is selected by hash done on
each packet. Controlled by: xmit_hash_policy of the
bond device.
- flags: Returns flags that are specific per lag @type. Valid only if
hardware lag is active.
* "shared_fdb" - "on" or "off", if "on" single FDB is used.

- mapping: Returns the mapping which is used to select egress port.
Valid only if hardware lag is active.
If @port_sel_mode is "hash" returns the active egress ports.
The hash result will select only active ports.
if @port_sel_mode is "queue_affinity" returns the mapping
between the configured port affinity of the QP/SQ and actual
egress port. For example:
* 1:1 - Mapping means if the configured affinity is port 1
traffic will egress via port 1.
* 1:2 - Mapping means if the configured affinity is port 1
traffic will egress via port 2. This can happen
if port 1 is down or in active/backup mode and port 1
is backup.

Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>