linux/net/bridge/br_switchdev.c
Vladimir Oltean e18f4c18ab net: switchdev: pass flags and mask to both {PRE_,}BRIDGE_FLAGS attributes
This switchdev attribute offers a counterproductive API for a driver
writer, because although br_switchdev_set_port_flag gets passed a
"flags" and a "mask", those are passed piecemeal to the driver, so while
the PRE_BRIDGE_FLAGS listener knows what changed because it has the
"mask", the BRIDGE_FLAGS listener doesn't, because it only has the final
value. But certain drivers can offload only certain combinations of
settings, like for example they cannot change unicast flooding
independently of multicast flooding - they must be both on or both off.
The way the information is passed to switchdev makes drivers not
expressive enough, and unable to reject this request ahead of time, in
the PRE_BRIDGE_FLAGS notifier, so they are forced to reject it during
the deferred BRIDGE_FLAGS attribute, where the rejection is currently
ignored.

This patch also changes drivers to make use of the "mask" field for edge
detection when possible.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-12 17:08:04 -08:00

175 lines
4.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <net/switchdev.h>
#include "br_private.h"
static int br_switchdev_mark_get(struct net_bridge *br, struct net_device *dev)
{
struct net_bridge_port *p;
/* dev is yet to be added to the port list. */
list_for_each_entry(p, &br->port_list, list) {
if (netdev_port_same_parent_id(dev, p->dev))
return p->offload_fwd_mark;
}
return ++br->offload_fwd_mark;
}
int nbp_switchdev_mark_set(struct net_bridge_port *p)
{
struct netdev_phys_item_id ppid = { };
int err;
ASSERT_RTNL();
err = dev_get_port_parent_id(p->dev, &ppid, true);
if (err) {
if (err == -EOPNOTSUPP)
return 0;
return err;
}
p->offload_fwd_mark = br_switchdev_mark_get(p->br, p->dev);
return 0;
}
void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
struct sk_buff *skb)
{
if (skb->offload_fwd_mark && !WARN_ON_ONCE(!p->offload_fwd_mark))
BR_INPUT_SKB_CB(skb)->offload_fwd_mark = p->offload_fwd_mark;
}
bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
const struct sk_buff *skb)
{
return !skb->offload_fwd_mark ||
BR_INPUT_SKB_CB(skb)->offload_fwd_mark != p->offload_fwd_mark;
}
/* Flags that can be offloaded to hardware */
#define BR_PORT_FLAGS_HW_OFFLOAD (BR_LEARNING | BR_FLOOD | \
BR_MCAST_FLOOD | BR_BCAST_FLOOD)
int br_switchdev_set_port_flag(struct net_bridge_port *p,
unsigned long flags,
unsigned long mask,
struct netlink_ext_ack *extack)
{
struct switchdev_attr attr = {
.orig_dev = p->dev,
};
struct switchdev_notifier_port_attr_info info = {
.attr = &attr,
};
int err;
mask &= BR_PORT_FLAGS_HW_OFFLOAD;
if (!mask)
return 0;
attr.id = SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS;
attr.u.brport_flags.val = flags;
attr.u.brport_flags.mask = mask;
/* We run from atomic context here */
err = call_switchdev_notifiers(SWITCHDEV_PORT_ATTR_SET, p->dev,
&info.info, extack);
err = notifier_to_errno(err);
if (err == -EOPNOTSUPP)
return 0;
if (err) {
if (extack && !extack->_msg)
NL_SET_ERR_MSG_MOD(extack,
"bridge flag offload is not supported");
return -EOPNOTSUPP;
}
attr.id = SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS;
attr.flags = SWITCHDEV_F_DEFER;
err = switchdev_port_attr_set(p->dev, &attr);
if (err) {
NL_SET_ERR_MSG_MOD(extack, "error setting offload flag on port");
return err;
}
return 0;
}
static void
br_switchdev_fdb_call_notifiers(bool adding, const unsigned char *mac,
u16 vid, struct net_device *dev,
bool added_by_user, bool offloaded)
{
struct switchdev_notifier_fdb_info info;
unsigned long notifier_type;
info.addr = mac;
info.vid = vid;
info.added_by_user = added_by_user;
info.offloaded = offloaded;
notifier_type = adding ? SWITCHDEV_FDB_ADD_TO_DEVICE : SWITCHDEV_FDB_DEL_TO_DEVICE;
call_switchdev_notifiers(notifier_type, dev, &info.info, NULL);
}
void
br_switchdev_fdb_notify(const struct net_bridge_fdb_entry *fdb, int type)
{
if (!fdb->dst)
return;
switch (type) {
case RTM_DELNEIGH:
br_switchdev_fdb_call_notifiers(false, fdb->key.addr.addr,
fdb->key.vlan_id,
fdb->dst->dev,
test_bit(BR_FDB_ADDED_BY_USER,
&fdb->flags),
test_bit(BR_FDB_OFFLOADED,
&fdb->flags));
break;
case RTM_NEWNEIGH:
br_switchdev_fdb_call_notifiers(true, fdb->key.addr.addr,
fdb->key.vlan_id,
fdb->dst->dev,
test_bit(BR_FDB_ADDED_BY_USER,
&fdb->flags),
test_bit(BR_FDB_OFFLOADED,
&fdb->flags));
break;
}
}
int br_switchdev_port_vlan_add(struct net_device *dev, u16 vid, u16 flags,
struct netlink_ext_ack *extack)
{
struct switchdev_obj_port_vlan v = {
.obj.orig_dev = dev,
.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
.flags = flags,
.vid = vid,
};
return switchdev_port_obj_add(dev, &v.obj, extack);
}
int br_switchdev_port_vlan_del(struct net_device *dev, u16 vid)
{
struct switchdev_obj_port_vlan v = {
.obj.orig_dev = dev,
.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
.vid = vid,
};
return switchdev_port_obj_del(dev, &v.obj);
}