[PATCH v4 net-next 2/9] net: bridge: offload all port flags at once in br_setport

Vladimir Oltean
2021-02-12T01:06:35Z

If for example this command:

ip link set swp0 type bridge_slave flood off mcast_flood off learning off

succeeded at configuring BR_FLOOD and BR_MCAST_FLOOD but not at
BR_LEARNING, there would be no attempt to revert the partial state in
any way. Arguably, if the user changes more than one flag through the
same netlink command, this one _should_ be all or nothing, which means
it should be passed through switchdev as all or nothing.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
Changes in v4:
Leave br->lock alone completely.

Changes in v3:
Don't attempt to drop br->lock around br_switchdev_set_port_flag now,
move that part to a later patch.

Changes in v2:
Patch is new.

Changes in v2:
Patch is new.

net/bridge/br_netlink.c | 109 ++++++++++++--------------------------
net/bridge/br_switchdev.c | 6 ++-
2 files changed, 39 insertions(+), 76 deletions(-)

diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index bd3962da345a..bf469f824944 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -853,87 +853,58 @@ static int br_set_port_state(struct net_bridge_port *p, u8 state)
}

/* Set/clear or port flags based on attribute */
-static int br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[],
- int attrtype, unsigned long mask)
+static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[],
+ int attrtype, unsigned long mask)
{
- unsigned long flags;
- int err;
-
if (!tb[attrtype])
- return 0;
+ return;

if (nla_get_u8(tb[attrtype]))
- flags = p->flags | mask;
+ p->flags |= mask;
else
- flags = p->flags & ~mask;
-
- err = br_switchdev_set_port_flag(p, flags, mask);
- if (err)
- return err;
-
- p->flags = flags;
- return 0;
+ p->flags &= ~mask;
}

/* Process bridge protocol info on port */
static int br_setport(struct net_bridge_port *p, struct nlattr *tb[])
{
- unsigned long old_flags = p->flags;
- bool br_vlan_tunnel_old = false;
+ unsigned long old_flags, changed_mask;
+ bool br_vlan_tunnel_old;
int err;

- err = br_set_port_flag(p, tb, IFLA_BRPORT_MODE, BR_HAIRPIN_MODE);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_GUARD, BR_BPDU_GUARD);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_FAST_LEAVE, BR_MULTICAST_FAST_LEAVE);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_LEARNING, BR_LEARNING);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_UNICAST_FLOOD, BR_FLOOD);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_MCAST_FLOOD, BR_MCAST_FLOOD);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_MCAST_TO_UCAST, BR_MULTICAST_TO_UNICAST);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_BCAST_FLOOD, BR_BCAST_FLOOD);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP, BR_PROXYARP);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP_WIFI, BR_PROXYARP_WIFI);
- if (err)
- return err;
-
- br_vlan_tunnel_old = (p->flags & BR_VLAN_TUNNEL) ? true : false;
- err = br_set_port_flag(p, tb, IFLA_BRPORT_VLAN_TUNNEL, BR_VLAN_TUNNEL);
- if (err)
+ old_flags = p->flags;
+ br_vlan_tunnel_old = (old_flags & BR_VLAN_TUNNEL) ? true : false;
+
+ br_set_port_flag(p, tb, IFLA_BRPORT_MODE, BR_HAIRPIN_MODE);
+ br_set_port_flag(p, tb, IFLA_BRPORT_GUARD, BR_BPDU_GUARD);
+ br_set_port_flag(p, tb, IFLA_BRPORT_FAST_LEAVE,
+ BR_MULTICAST_FAST_LEAVE);
+ br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK);
+ br_set_port_flag(p, tb, IFLA_BRPORT_LEARNING, BR_LEARNING);
+ br_set_port_flag(p, tb, IFLA_BRPORT_UNICAST_FLOOD, BR_FLOOD);
+ br_set_port_flag(p, tb, IFLA_BRPORT_MCAST_FLOOD, BR_MCAST_FLOOD);
+ br_set_port_flag(p, tb, IFLA_BRPORT_MCAST_TO_UCAST,
+ BR_MULTICAST_TO_UNICAST);
+ br_set_port_flag(p, tb, IFLA_BRPORT_BCAST_FLOOD, BR_BCAST_FLOOD);
+ br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP, BR_PROXYARP);
+ br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP_WIFI, BR_PROXYARP_WIFI);
+ br_set_port_flag(p, tb, IFLA_BRPORT_VLAN_TUNNEL, BR_VLAN_TUNNEL);
+ br_set_port_flag(p, tb, IFLA_BRPORT_NEIGH_SUPPRESS, BR_NEIGH_SUPPRESS);
+ br_set_port_flag(p, tb, IFLA_BRPORT_ISOLATED, BR_ISOLATED);
+
+ changed_mask = old_flags ^ p->flags;
+
+ err = br_switchdev_set_port_flag(p, p->flags, changed_mask);
+ if (err) {
+ p->flags = old_flags;
return err;
+ }

if (br_vlan_tunnel_old && !(p->flags & BR_VLAN_TUNNEL))
nbp_vlan_tunnel_info_flush(p);

+ br_port_flags_change(p, changed_mask);
+
if (tb[IFLA_BRPORT_COST]) {
err = br_stp_set_path_cost(p, nla_get_u32(tb[IFLA_BRPORT_COST]));
if (err)
@@ -982,15 +953,6 @@ static int br_setport(struct net_bridge_port *p, struct nlattr *tb[])
p->group_fwd_mask = fwd_mask;
}

- err = br_set_port_flag(p, tb, IFLA_BRPORT_NEIGH_SUPPRESS,
- BR_NEIGH_SUPPRESS);
- if (err)
- return err;
-
- err = br_set_port_flag(p, tb, IFLA_BRPORT_ISOLATED, BR_ISOLATED);
- if (err)
- return err;
-
if (tb[IFLA_BRPORT_BACKUP_PORT]) {
struct net_device *backup_dev = NULL;
u32 backup_ifindex;
@@ -1008,7 +970,6 @@ static int br_setport(struct net_bridge_port *p, struct nlattr *tb[])
return err;
}

- br_port_flags_change(p, old_flags ^ p->flags);
return 0;
}

diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
index a9c23ef83443..6a9db6aa5c04 100644
--- a/net/bridge/br_switchdev.c
+++ b/net/bridge/br_switchdev.c
@@ -65,16 +65,18 @@ int br_switchdev_set_port_flag(struct net_bridge_port *p,
struct switchdev_attr attr = {
.orig_dev = p->dev,
.id = SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS,
- .u.brport_flags = mask,
};
struct switchdev_notifier_port_attr_info info = {
.attr = &attr,
};
int err;

- if (mask & ~BR_PORT_FLAGS_HW_OFFLOAD)
+ mask &= BR_PORT_FLAGS_HW_OFFLOAD;
+ if (!mask)
return 0;

+ attr.u.brport_flags = mask;
+
/* We run from atomic context here */
err = call_switchdev_notifiers(SWITCHDEV_PORT_ATTR_SET, p->dev,
&info.info, NULL);
--
2.25.1