mlxsw: spectrum_matchall: Perform priority checks earlier

Perform the priority check earlier in the function instead of repeating
it for every action. This fixes a bug that allowed matchall rules with
sample action to be added in front of flower rules on egress.

Fixes: 54d0e963f683 ("mlxsw: spectrum_matchall: Add support for egress sampling")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: spectrum_matchall: Convert if statements to a switch statement

Previous patch moved the protocol check out of the action check, so
these if statements can now be converted to a switch statement. Perform
the conversion.

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

mlxsw: spectrum_matchall: Perform protocol check earlier

Perform the protocol check earlier in the function instead of repeating
it for every action. Example:

# tc filter add dev swp1 ingress proto ip matchall skip_sw action sample group 1 rate 100
Error: matchall rules only supported with 'all' protocol.
We have an error talking to the kernel

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

mlxsw: spectrum_matchall: Add support for egress sampling

Allow user space to install a matchall classifier with sample action on
egress. This is only supported on Spectrum-2 onwards, so Spectrum-1 will
continue to return an error.

Programming the hardware to sample on egress is identical to ingress
sampling with the sole change of using a different sampling trigger.

Upon receiving a sampled packet, the sampling trigger (ingress vs.
egress) will be encoded in the mirroring reason in the Completion Queue
Element (CQE). The mirroring reason is used to lookup the sampling
parameters (e.g., psample group) which are passed to the psample module.

Note that locally generated packets that are sampled are simply
consumed. This is done for several reasons.

First, such packets do not have an ingress netdev given that their Rx
local port is the CPU port. This breaks several basic assumptions.

Second, sampling using the same interface (tc), but with flower
classifier will not result in locally generated packets being sampled
given that such packets are not subject to the policy engine.

Third, realistically, this is not a big deal given that the vast
majority of the packets being transmitted through the port are not
locally generated packets.

Fourth, if such packets do need to be sampled, they can be sampled with
a 'skip_hw' filter and reported to the same sampling group as the data
path packets. The software sampling rate can also be adjusted to fit the
rate of the locally generated packets which is much lower than the rate
of the data path traffic.

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

mlxsw: spectrum: Start using sampling triggers hash table

Start using the previously introduced sampling triggers hash table to
store sampling parameters instead of storing them as attributes of the
sampled port.

This makes it easier to introduce new sampling triggers.

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

mlxsw: spectrum_matchall: Pass matchall entry to sampling operations

The entry will be required by the next patches, so pass it. No
functional changes intended.

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

mlxsw: spectrum_matchall: Push sampling checks to per-ASIC operations

Push some sampling checks to the per-ASIC operations, as they are no
longer relevant for all ASICs.

The sampling rate validation against the MPSC maximum rate is only
relevant for Spectrum-1, as Spectrum-2 and later ASICs no longer use
MPSC register for sampling.

The ingress / egress validation is pushed down to the per-ASIC
operations since subsequent patches are going to remove it for
Spectrum-2 and later ASICs.

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

mlxsw: spectrum_matchall: Propagate extack further

Due to the differences between Spectrum-1 and later ASICs, some of the
checks currently performed at the common code (where extack is
available) will need to be pushed to the per-ASIC operations.

As a preparation, propagate extack further to maintain proper error
reporting.

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

mlxsw: spectrum_matchall: Implement sampling using mirroring

Spectrum-2 and later ASICs support sampling of packets by mirroring to
the CPU with probability. There are several advantages compared to the
legacy dedicated sampling mechanism:

* Extra metadata per-packet: Egress port, egress traffic class, traffic
class occupancy and end-to-end latency
* Ability to sample packets on egress / per-flow

Convert Spectrum-2 and later ASICs to perform sampling by mirroring to
the CPU with probability.

Subsequent patches will add support for egress / per-flow sampling and
expose the extra metadata.

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

mlxsw: spectrum_matchall: Split sampling support between ASICs

Sampling of ingress packets is supported using a dedicated sampling
mechanism on all Spectrum ASICs. However, Spectrum-2 and later ASICs
support more sophisticated sampling by mirroring packets to the CPU.

As a preparation for more advanced sampling configurations, split the
sampling operations between Spectrum-1 and later ASICs.

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

mlxsw: spectrum_span: Add SPAN probability rate support

Currently, every packet that matches a mirroring trigger (e.g., received
packets, buffer dropped packets) is mirrored. Spectrum-2 and later ASICs
support mirroring with probability, where every 1 in N matched packets
is mirrored.

Extend the API that creates the binding between the trigger and the SPAN
agent with a probability rate parameter, which is an attribute of the
trigger. Set it to '1' to maintain existing behavior.

Subsequent patches will use it to perform more sophisticated sampling,
by mirroring packets to the CPU with probability.

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

mlxsw: spectrum_span: Allow setting policer on a SPAN agent

When mirroring packets to the CPU port the mirrored packets are trapped
to the CPU. However, unlike other traps, it is not possible to set a
policer on the associated trap group. Instead, the policer needs to be
set on the SPAN agent.

Moreover, the policer ID must be within a specified range: From a
configurable (even) base ID to this base plus the maximum number of SPAN
agents.

While the immediate use case is to set the policer on a SPAN agent that
mirrors to the CPU port, a policer can be set on any SPAN agent.
Therefore, the operation is implemented for all SPAN agent types.

Extend the SPAN agent request API to allow passing the desired policer
ID that should be bound to the SPAN agent. Return an error for
Spectrum-1, as it does not support policer setting on a SPAN agent.

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

mlxsw: spectrum_span: Allow passing parameters to SPAN agents

Currently, the only parameter of a SPAN agent is the netdev which
the SPAN agent should mirror to.

The next patch will add the ability to request a SPAN agent that mirrors
to a specific netdev and has a specific policer ID bound to it. This is
required when mirroring packets to the CPU port.

Therefore, encapsulate the sole parameter to mlxsw_sp_span_agent_get()
in a structure, so that it could later be extended with policer
information.

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

mlxsw: spectrum_matchall: Publish matchall data structures

A following patch introduces offloading of filters attached to blocks bound
to the RED tail_drop qevent. The only classifier that mlxsw will permit in
this role is matchall. mlxsw currently offloads matchall filters used with
clsact qdisc. The data structures used for that offload will come handy for
the qevent offload as well. Publish them in spectrum.h.

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

mlxsw: spectrum_matchall: Forbid to insert matchall rules in collision with flower rules

On ingress, the matchall rules doing mirroring and sampling are offloaded
into hardware blocks that are processed before any flower rules.
On egress, the matchall mirroring rules are offloaded into hardware
block that is processed after all flower rules.

Therefore check the priorities of inserted matchall rules against
existing flower rules and ensure the correct ordering.

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

mlxsw: spectrum_matchall: Expose a function to get min and max rule priority

Introduce an infrastructure that allows to get minimum and maximum
rule priority for specified chain. This is going to be used by
a subsequent patch to enforce ordering between flower and
matchall filters.

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

mlxsw: spectrum_matchall: Put matchall list into substruct of flow struct

As there are going to be other matchall specific fields in flow
structure, put the existing list field into matchall substruct.

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

mlxsw: spectrum_matchall: Restrict sample action to be allowed only on ingress

HW supports packet sampling on ingress only. Check and fail if user
is adding sample on egress.

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

mlxsw: spectrum: Convert matchall-based mirroring to new SPAN API

In matchall-based mirroring, mirroring is not done with ACLs, but a SPAN
agent is bound to the ingress / egress of a port and all incoming /
outgoing traffic is mirrored.

Convert this type of mirroring to use the new API.

First the SPAN agent is resolved, then the port is marked as analyzed
and its egress mirror buffer is potentially allocated. Lastly, the
binding is performed.

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

mlxsw: spectrum_matchall: Process matchall events from the same cb as flower

Currently there are two callbacks registered: one for matchall,
one for flower. This causes the user to see "in_hw_count 2" in TC filter
dump. Because of this and also as a preparation for future matchall
offload for rules equivalent to flower-all-match, move the processing of
shared block into matchall.c. Leave only one cb for mlxsw driver
per-block.

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: Avoid copying sample values and use RCU pointer direcly instead

Currently, only the psample_group is accessed using RCU on RX path.
However, it is possible (unlikely) that other sample values get change
during RX processing. Fix this by having the port->sample struct
accessed as RCU pointer, containing all sample values including
psample_group pointer. That avoids extra alloc per-port, copying the
values and the race condition described above.

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_matchall: Push per-port rule add/del into separate functions

As the replace/destroy is going to be used later on per-block, push
the per-port rule addition/deletion into separate functions.

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_matchall: Move ingress indication into mall_entry

Instead of having it in mirror_entry structure, move it to mall_entry
and set it during rule insertion.

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_matchall: Pass mall_entry as arg to mlxsw_sp_mall_port_sample_add()

In the preparation for future changes, have the
mlxsw_sp_mall_port_sample_add() function to accept mall_entry including
all needed info originally obtained from cls and act pointers.

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_matchall: Pass mall_entry as arg to mlxsw_sp_mall_port_mirror_add()

In the preparation for future changes, have the
mlxsw_sp_mall_port_mirror_add() function to accept mall_entry including
the "to_dev" originally obtained from act pointer.

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: Push matchall bits into a separate file

Similar to flower, have matchall related code in a separate file.
Do some small renaming on the way (consistent "mall" prefixes,
dropped "_tc_", dropped "_port_" where suitable).

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>