net/mlx5e: Extract remaining tunnel encap code to dedicated file

Move set_encap_dests() and clean_encap_dests() to the tunnel encap
dedicated file. And rename them to mlx5e_tc_tun_encap_dests_set()
and mlx5e_tc_tun_encap_dests_unset().

No functional change in this patch. It is needed in the next patch.

Signed-off-by: Chris Mi <cmi@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5e: Offload rule only when all encaps are valid

The cited commit adds a for loop to support multiple encapsulations.
But it only checks if the last encap is valid.

Fix it by setting slow path flag when one of the encap is invalid.

Fixes: f493f15534ec ("net/mlx5e: Move flow attr reformat action bit to per dest flags")
Signed-off-by: Chris Mi <cmi@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5e: Pass attr arg for attaching/detaching encaps

In later commit that we will have multiple attr instances per flow
we would like to pass a specific attr instance to set encaps.

Currently the mlx5_flow object contains a single mlx5_attr instance.
However, multi table actions (e.g. CT) instantiate multiple attr instances.

Currently mlx5e_attach/detach_encap() reads the first attr instance
from the flow instance. Modify the functions to receive the attr
instance as a parameter which is set by the calling function.

Signed-off-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Oz Shlomo <ozsh@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5e: Handle FIB events to update tunnel endpoint device

Process FIB route update events to dynamically update the stack device
rules when tunnel routing changes. Use rtnl lock to prevent FIB event
handler from running concurrently with neigh update and neigh stats
workqueue tasks. Use encap_tbl_lock mutex to synchronize with TC rule
update path that doesn't use rtnl lock.

FIB event workflow for encap flows:

- Unoffload all flows attached to route encaps from slow or fast path
depending on encap destination endpoint neigh state.

- Update encap IP header according to new route dev.

- Update flows mod_hdr action that is responsible for overwriting reg_c0
source port bits to source port of new underlying VF of new route dev. This
step requires changing flow create/delete code to save flow parse attribute
mod_hdr_acts structure for whole flow lifetime instead of deallocating it
after flow creation. Refactor mod_hdr code to allow saving id of individual
mod_hdr actions and updating them with dedicated helper.

- Offload all flows to either slow or fast path depending on encap
destination endpoint neigh state.

FIB event workflow for decap flows:

- Unoffload all route flows from hardware. When last route flow is deleted
all indirect table rules for the route dev will also be deleted.

- Update flow attr decap_vport and destination MAC according to underlying
VF of new rote dev.

- Offload all route flows back to hardware creating new indirect table
rules according to updated flow attribute data.

Extract some neigh update code to helper functions to be used by both neigh
update and route update infrastructure.

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5e: Create route entry infrastructure

Implement dedicated route entry infrastructure to be used in following
patch by route update event. Both encap (indirectly through their
corresponding encap entries) and decap (directly) flows are attached to
routing entry. Since route update also requires updating encap (route
device MAC address is a source MAC address of tunnel encapsulation), same
encap_tbl_lock mutex is used for synchronization.

The new infrastructure looks similar to existing infrastructures for shared
encap, mod_hdr and hairpin entries:

- Per-eswitch hash table is used for quick entry lookup.

- Flows are attached to per-entry linked list and hold reference to entry
during their lifetime.

- Atomic reference counting and rcu mechanisms are used as synchronization
primitives for concurrent access.

The infrastructure also enables connection tracking on stacked devices
topology by attaching CT chain 0 flow on tunneling dev to decap route
entry.

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

net/mlx5e: Extract tc tunnel encap/decap code to dedicated file

Following patches in series extend the extracted code with routing
infrastructure. To improve code modularity created a dedicated
tc_tun_encap.c source file and move encap/decap related code to the new
file. Export code that is used by both regular TC code and encap/decap code
into tc_priv.h (new header intended to be used only by TC module). Rename
some exported functions by adding "mlx5e_" prefix to their names.

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>