In this talk Elad Raz from Mellanox Technologies talks about his effort to open source switch development and transition from proprietary SDKs to a standard, in-kernel solution.

1. Elad Raz, Jiri Pirko
Kernel TLV | 2016
Switchdev – No More SDK

2. © 2016 Mellanox Technologies 2
Switchdev is here to stay
What?
Why?
Where?

3. © 2016 Mellanox Technologies 3
Switchdev is here to stay
What?
Why?
Where?

4. © 2016 Mellanox Technologies 4
Switchdev is here to stay
What?
64 net-devices
Doing skb rx/tx, ethtool, port state and ndo offload

5. © 2016 Mellanox Technologies 5
Switchdev is here to stay
What?
switchdev_ops
.1D/.1Q Bridging – VLANs, PVID, FDB, IGMP…
Routing – FIB offload
and more

6. © 2016 Mellanox Technologies 6
Switchdev is here to stay
What?
In-kernel implementation
NO MORE SDK!
drivers/net/ethernet/mellanox/mlxsw

7. © 2016 Mellanox Technologies 7
Switchdev is here to stay
Devlink
set port type, port splitter, shared buffers, etc.
What?

8. © 2016 Mellanox Technologies 8
Switchdev is here to stay
QoS, Shared buffer
DCBNL interface implementation
What?

9. © 2016 Mellanox Technologies 9
Switchdev is here to stay
L3 offload
fix the current switchdev model, include VRF support
What?

10. © 2016 Mellanox Technologies 10
Switchdev is here to stay
What?
Why?
Where?
pen

11. © 2016 Mellanox Technologies 11
Switchdev is here to stay
Why?
Community based
Open-source
Standard behavior
Standard API

12. © 2016 Mellanox Technologies 12
Switchdev is here to stay
What?
Why?
Where?

13. © 2016 Mellanox Technologies 13
Switchdev is here to stay
Where?
Flows
tc cls_flower + selected acts offload

14. © 2016 Mellanox Technologies 14
Switchdev is here to stay
Where?
(e)BPF?

15. © 2016 Mellanox Technologies 15
SWITCHDEV
commit 007f790c8276271de26416f90d55561bcc96588a
Author: Jiri Pirko <jiri@resnulli.us>
Date: Fri Nov 28 14:34:17 2014 +0100
net: introduce generic switch devices support
The goal of this is to provide a possibility to support various switch
chips. Drivers should implement relevant ndos to do so. Now there is
only one ndo defined:
- for getting physical switch id is in place.
Note that user can use random port netdevice to access the switch.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Reviewed-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

16. © 2016 Mellanox Technologies 16
ROCKER
commit 4b8ac9660af07be6f6602b523929793eed314997
Author: Jiri Pirko <jiri@resnulli.us>
Date: Fri Nov 28 14:34:26 2014 +0100
rocker: introduce rocker switch driver
This patch introduces the first driver to benefit from the switchdev
infrastructure and to implement newly introduced switch ndos. This is a
driver for emulated switch chip implemented in qemu:
https://github.com/sfeldma/qemu-rocker/
This patch is a result of joint work with Scott Feldman.
Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Reviewed-by: Thomas Graf <tgraf@suug.ch>
Reviewed-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

17. © 2016 Mellanox Technologies 17
MLXSW
commit 93c1edb27f9e7ef7f276b91763c93242bbda71cb
Author: Jiri Pirko <jiri@mellanox.com>
Date: Wed Jul 29 23:33:46 2015 +0200
mlxsw: Introduce Mellanox switch driver core
Add core components of Mellanox switch driver infrastructure.
Core infrastructure is designed so that it can be used by multiple
bus drivers (PCI now, I2C and SGMII are planned to be implemented
in the future). Multiple switch kind drivers can be registered as well.
This core serves as a glue between buses and drivers.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Elad Raz <eladr@mellanox.com>
Reviewed-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

18. © 2016 Mellanox Technologies 18
ndo_ops
static const struct net_device_ops mlxsw_sp_port_netdev_ops = {
.ndo_open = mlxsw_sp_port_open,
.ndo_stop = mlxsw_sp_port_stop,
.ndo_start_xmit = mlxsw_sp_port_xmit,
.ndo_set_rx_mode = mlxsw_sp_set_rx_mode,
.ndo_set_mac_address = mlxsw_sp_port_set_mac_address,
.ndo_change_mtu = mlxsw_sp_port_change_mtu,
.ndo_get_stats64 = mlxsw_sp_port_get_stats64,
.ndo_vlan_rx_add_vid = mlxsw_sp_port_add_vid,
.ndo_vlan_rx_kill_vid = mlxsw_sp_port_kill_vid,
.ndo_fdb_add = switchdev_port_fdb_add,
.ndo_fdb_del = switchdev_port_fdb_del,
.ndo_fdb_dump = switchdev_port_fdb_dump,
.ndo_bridge_setlink = switchdev_port_bridge_setlink,
.ndo_bridge_getlink = switchdev_port_bridge_getlink,
.ndo_bridge_dellink = switchdev_port_bridge_dellink,
};

19. © 2016 Mellanox Technologies 19
switchdev_ops
static const struct switchdev_ops mlxsw_sp_port_switchdev_ops = {
.switchdev_port_attr_get = mlxsw_sp_port_attr_get,
.switchdev_port_attr_set = mlxsw_sp_port_attr_set,
.switchdev_port_obj_add = mlxsw_sp_port_obj_add,
.switchdev_port_obj_del = mlxsw_sp_port_obj_del,
.switchdev_port_obj_dump = mlxsw_sp_port_obj_dump,
};

20. © 2016 Mellanox Technologies 20
switchdev_attr
enum switchdev_attr_id {
SWITCHDEV_ATTR_ID_UNDEFINED,
SWITCHDEV_ATTR_ID_PORT_PARENT_ID,
SWITCHDEV_ATTR_ID_PORT_STP_STATE,
SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS,
SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME,
SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING,
};
struct switchdev_attr {
struct net_device *orig_dev;
enum switchdev_attr_id id;
u32 flags;
void *complete_priv;
void (*complete)(struct net_device *dev, int err, void *priv);
union {
struct netdev_phys_item_id ppid; /* PORT_PARENT_ID */
u8 stp_state; /* PORT_STP_STATE */
unsigned long brport_flags; /* PORT_BRIDGE_FLAGS */
u32 ageing_time; /* BRIDGE_AGEING_TIME */
bool vlan_filtering; /* BRIDGE_VLAN_FILTERING */
} u;
};

21. © 2016 Mellanox Technologies 21
switchdev_obj
enum switchdev_obj_id {
SWITCHDEV_OBJ_ID_UNDEFINED,
SWITCHDEV_OBJ_ID_PORT_VLAN,
SWITCHDEV_OBJ_ID_IPV4_FIB,
SWITCHDEV_OBJ_ID_PORT_FDB,
SWITCHDEV_OBJ_ID_PORT_MDB,
};
struct switchdev_obj {
struct net_device *orig_dev;
enum switchdev_obj_id id;
u32 flags;
void *complete_priv;
void (*complete)(struct net_device *dev, int err, void *priv);
};
/* SWITCHDEV_OBJ_ID_PORT_FDB */
struct switchdev_obj_port_fdb {
struct switchdev_obj obj;
unsigned char addr[ETH_ALEN];
u16 vid;
u16 ndm_state;
};

22. © 2016 Mellanox Technologies 22
call_switchdev_notifiers
info.addr = mac;
info.vid = vid;
notifier_type = adding ? SWITCHDEV_FDB_ADD : SWITCHDEV_FDB_DEL;
call_switchdev_notifiers(notifier_type, dev, &info.info);

23. © 2016 Mellanox Technologies 23
NETDEV_CHANGEUPPER
register_netdevice_notifier informs using
NETDEV_(PRE)CHANGEUPPER about:
• VLANs
• Bridges
• LAGs (Team/bond)

24. Thank You