Re: [PATCH net-next v2 2/7] net: switchdev: support static FDB addresses

On Thu, Aug 6, 2015 at 7:19 AM, Vivien Didelot
[off-list ref] wrote:

On 15-08-05 23:28:15, Scott Feldman wrote:

quoted

On Wed, Aug 5, 2015 at 10:44 PM, Vivien Didelot
[off-list ref] wrote:

quoted

This patch adds a is_static boolean to the switchdev_obj_fdb structure,
in order to set the ndm_state to either NUD_NOARP or NUD_REACHABLE.

Signed-off-by: Vivien Didelot <redacted>
---
 include/net/switchdev.h   | 1 +
 net/switchdev/switchdev.c | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/net/switchdev.h b/include/net/switchdev.h
index e90e1a0..0e296b8 100644
--- a/include/net/switchdev.h
+++ b/include/net/switchdev.h

@@ -72,6 +72,7 @@ struct switchdev_obj {
                struct switchdev_obj_fdb {              /* PORT_FDB */
                        u8 addr[ETH_ALEN];
                        u16 vid;
+                       bool is_static;

What do you think about changing this to u16 ndm_state?  That way, it
can be used on input (fdb add) and output (fdb dump), and the driver
can privately track the state, kind of like how the bridge keeps
is_static, is_local, etc.

I'm OK with the change. Should we consider NUD_NONE (0) a valid value?

quoted

quoted

                } fdb;
        } u;
 };

diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
index 9db87a3..e9d1cac 100644
--- a/net/switchdev/switchdev.c
+++ b/net/switchdev/switchdev.c

@@ -811,7 +811,7 @@ static int switchdev_port_fdb_dump_cb(struct net_device *dev,
        ndm->ndm_flags   = NTF_SELF;
        ndm->ndm_type    = 0;
        ndm->ndm_ifindex = dev->ifindex;
-       ndm->ndm_state   = NUD_REACHABLE;
+       ndm->ndm_state   = obj->u.fdb.is_static ? NUD_NOARP : NUD_REACHABLE;

In other word, do we prefer this:

    ndm->ndm_state = obj->u.fdb.ndm_state == NUD_NONE ?
                     NUD_REACHABLE : obj->u.fdb.ndm_state;

Or this (meaning switchdev users cannot leave it blank and must at least
set NUD_REACHABLE themselves):

    ndm->ndm_state = obj->u.fdb.ndm_state;

My preference would be this option.