diff options
Diffstat (limited to 'Documentation/networking')
| -rw-r--r-- | Documentation/networking/switchdev.txt | 53 |
1 files changed, 29 insertions, 24 deletions
diff --git a/Documentation/networking/switchdev.txt b/Documentation/networking/switchdev.txt index 00c703ce6903..da82cd75a4f6 100644 --- a/Documentation/networking/switchdev.txt +++ b/Documentation/networking/switchdev.txt @@ -300,33 +300,38 @@ IGMP Snooping XXX: complete this section -L3 routing ----------- +L3 Routing Offload +------------------ Offloading L3 routing requires that device be programmed with FIB entries from the kernel, with the device doing the FIB lookup and forwarding. The device does a longest prefix match (LPM) on FIB entries matching route prefix and -forwards the packet to the matching FIB entry's nexthop(s) egress ports. To -program the device, the switchdev driver is called with add/delete ops for IPv4 -and IPv6 FIB entries. For IPv4, the driver implements switchdev ops: - - int (*switchdev_fib_ipv4_add)(struct net_device *dev, - __be32 dst, int dst_len, - struct fib_info *fi, - u8 tos, u8 type, - u32 nlflags, u32 tb_id); - - int (*switchdev_fib_ipv4_del)(struct net_device *dev, - __be32 dst, int dst_len, - struct fib_info *fi, - u8 tos, u8 type, - u32 tb_id); - -to add/delete IPv4 dst/dest_len prefix on table tb_id. The *fi structure holds -details on the route and route's nexthops. *dev is one of the port netdevs -mentioned in the routes next hop list. If the output port netdevs referenced -in the route's nexthop list don't all have the same switch ID, the driver is -not called to add/delete the FIB entry. +forwards the packet to the matching FIB entry's nexthop(s) egress ports. + +To program the device, the driver implements support for +SWITCHDEV_OBJ_IPV[4|6]_FIB object using switchdev_port_obj_xxx ops. +switchdev_port_obj_add is used for both adding a new FIB entry to the device, +or modifying an existing entry on the device. + +XXX: Currently, only SWITCHDEV_OBJ_IPV4_FIB objects are supported. + +SWITCHDEV_OBJ_IPV4_FIB object passes: + + struct switchdev_obj_ipv4_fib { /* IPV4_FIB */ + u32 dst; + int dst_len; + struct fib_info *fi; + u8 tos; + u8 type; + u32 nlflags; + u32 tb_id; + } ipv4_fib; + +to add/modify/delete IPv4 dst/dest_len prefix on table tb_id. The *fi +structure holds details on the route and route's nexthops. *dev is one of the +port netdevs mentioned in the routes next hop list. If the output port netdevs +referenced in the route's nexthop list don't all have the same switch ID, the +driver is not called to add/modify/delete the FIB entry. Routes offloaded to the device are labeled with "offload" in the ip route listing: @@ -344,7 +349,7 @@ listing: 12.0.0.4 via 11.0.0.9 dev sw1p2 proto zebra metric 20 offload 192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.15 -XXX: add/del IPv6 FIB API +XXX: add/mod/del IPv6 FIB API Nexthop Resolution ^^^^^^^^^^^^^^^^^^ |