devlink: introduce possibility to expose info about nested devlinks

In mlx5, there is a devlink instance created for PCI device. Also, one
separate devlink instance is created for auxiliary device that
represents the netdev of uplink port. This relation is currently
invisible to the devlink user.

Benefit from the rel infrastructure and allow for nested devlink
instance to set the relationship for the nested-in devlink instance.
Note that there may be many nested instances, therefore use xarray to
hold the list of rel_indexes for individual nested instances.

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

diff --git a/include/net/devlink.h b/include/net/devlink.h
index 0dfcd7d7fa18a217f763d42e8c5e003c369df73e..fad8e36e3d9889d4803dae232b748519c6e4fd1a 100644 (file)
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -1921,6 +1921,8 @@ devlink_health_reporter_state_update(struct devlink_health_reporter *reporter,
 void
 devlink_health_reporter_recovery_done(struct devlink_health_reporter *reporter);
 
+int devl_nested_devlink_set(struct devlink *devlink,
+                           struct devlink *nested_devlink);
 bool devlink_is_reload_failed(const struct devlink *devlink);
 void devlink_remote_reload_actions_performed(struct devlink *devlink,
                                             enum devlink_reload_limit limit,

diff --git a/net/devlink/core.c b/net/devlink/core.c
index 2a98ff9a2f6b5b3fcc0f80d17ab696ea564c166b..bcbbb952569f559a69bf6afc00be35ed330174c2 100644 (file)
--- a/net/devlink/core.c
+++ b/net/devlink/core.c
@@ -430,6 +430,7 @@ struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
        xa_init_flags(&devlink->ports, XA_FLAGS_ALLOC);
        xa_init_flags(&devlink->params, XA_FLAGS_ALLOC);
        xa_init_flags(&devlink->snapshot_ids, XA_FLAGS_ALLOC);
+       xa_init_flags(&devlink->nested_rels, XA_FLAGS_ALLOC);
        write_pnet(&devlink->_net, net);
        INIT_LIST_HEAD(&devlink->rate_list);
        INIT_LIST_HEAD(&devlink->linecard_list);
@@ -476,6 +477,7 @@ void devlink_free(struct devlink *devlink)
        WARN_ON(!list_empty(&devlink->linecard_list));
        WARN_ON(!xa_empty(&devlink->ports));
 
+       xa_destroy(&devlink->nested_rels);
        xa_destroy(&devlink->snapshot_ids);
        xa_destroy(&devlink->params);
        xa_destroy(&devlink->ports);

diff --git a/net/devlink/dev.c b/net/devlink/dev.c
index 3ae26d9088ab35a4fb16ef987b5d5415fff414f4..dc8039ca2b388bc360a6191910ee7848284445bf 100644 (file)
--- a/net/devlink/dev.c
+++ b/net/devlink/dev.c
@@ -138,6 +138,23 @@ nla_put_failure:
        return -EMSGSIZE;
 }
 
+static int devlink_nl_nested_fill(struct sk_buff *msg, struct devlink *devlink)
+{
+       unsigned long rel_index;
+       void *unused;
+       int err;
+
+       xa_for_each(&devlink->nested_rels, rel_index, unused) {
+               err = devlink_rel_devlink_handle_put(msg, devlink,
+                                                    rel_index,
+                                                    DEVLINK_ATTR_NESTED_DEVLINK,
+                                                    NULL);
+               if (err)
+                       return err;
+       }
+       return 0;
+}
+
 static int devlink_nl_fill(struct sk_buff *msg, struct devlink *devlink,
                           enum devlink_command cmd, u32 portid,
                           u32 seq, int flags)
@@ -164,6 +181,10 @@ static int devlink_nl_fill(struct sk_buff *msg, struct devlink *devlink,
                goto dev_stats_nest_cancel;
 
        nla_nest_end(msg, dev_stats);
+
+       if (devlink_nl_nested_fill(msg, devlink))
+               goto nla_put_failure;
+
        genlmsg_end(msg, hdr);
        return 0;
 
@@ -230,6 +251,34 @@ int devlink_nl_get_dumpit(struct sk_buff *msg, struct netlink_callback *cb)
        return devlink_nl_dumpit(msg, cb, devlink_nl_get_dump_one);
 }
 
+static void devlink_rel_notify_cb(struct devlink *devlink, u32 obj_index)
+{
+       devlink_notify(devlink, DEVLINK_CMD_NEW);
+}
+
+static void devlink_rel_cleanup_cb(struct devlink *devlink, u32 obj_index,
+                                  u32 rel_index)
+{
+       xa_erase(&devlink->nested_rels, rel_index);
+}
+
+int devl_nested_devlink_set(struct devlink *devlink,
+                           struct devlink *nested_devlink)
+{
+       u32 rel_index;
+       int err;
+
+       err = devlink_rel_nested_in_add(&rel_index, devlink->index, 0,
+                                       devlink_rel_notify_cb,
+                                       devlink_rel_cleanup_cb,
+                                       nested_devlink);
+       if (err)
+               return err;
+       return xa_insert(&devlink->nested_rels, rel_index,
+                        xa_mk_value(0), GFP_KERNEL);
+}
+EXPORT_SYMBOL_GPL(devl_nested_devlink_set);
+
 void devlink_notify_register(struct devlink *devlink)
 {
        devlink_notify(devlink, DEVLINK_CMD_NEW);

diff --git a/net/devlink/devl_internal.h b/net/devlink/devl_internal.h
index 4cb534aff44db7d912527968962dc4444a8f93e3..741d1bf1bec888087b01d1d99868d614bafd7641 100644 (file)
--- a/net/devlink/devl_internal.h
+++ b/net/devlink/devl_internal.h
@@ -58,6 +58,7 @@ struct devlink {
        refcount_t refcount;
        struct rcu_work rwork;
        struct devlink_rel *rel;
+       struct xarray nested_rels;
        char priv[] __aligned(NETDEV_ALIGN);
 };