https://github.com/torvalds/linux
Tip revision: 5d0c230f1de8c7515b6567d9afba1f196fb4e2f4 authored by Linus Torvalds on 30 July 2023, 20:23:47 UTC
Linux 6.5-rc4
Linux 6.5-rc4
Tip revision: 5d0c230
br_switchdev.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/ip.h>
#include <net/switchdev.h>
#include "br_private.h"
static struct static_key_false br_switchdev_tx_fwd_offload;
static bool nbp_switchdev_can_offload_tx_fwd(const struct net_bridge_port *p,
const struct sk_buff *skb)
{
if (!static_branch_unlikely(&br_switchdev_tx_fwd_offload))
return false;
return (p->flags & BR_TX_FWD_OFFLOAD) &&
(p->hwdom != BR_INPUT_SKB_CB(skb)->src_hwdom);
}
bool br_switchdev_frame_uses_tx_fwd_offload(struct sk_buff *skb)
{
if (!static_branch_unlikely(&br_switchdev_tx_fwd_offload))
return false;
return BR_INPUT_SKB_CB(skb)->tx_fwd_offload;
}
void br_switchdev_frame_set_offload_fwd_mark(struct sk_buff *skb)
{
skb->offload_fwd_mark = br_switchdev_frame_uses_tx_fwd_offload(skb);
}
/* Mark the frame for TX forwarding offload if this egress port supports it */
void nbp_switchdev_frame_mark_tx_fwd_offload(const struct net_bridge_port *p,
struct sk_buff *skb)
{
if (nbp_switchdev_can_offload_tx_fwd(p, skb))
BR_INPUT_SKB_CB(skb)->tx_fwd_offload = true;
}
/* Lazily adds the hwdom of the egress bridge port to the bit mask of hwdoms
* that the skb has been already forwarded to, to avoid further cloning to
* other ports in the same hwdom by making nbp_switchdev_allowed_egress()
* return false.
*/
void nbp_switchdev_frame_mark_tx_fwd_to_hwdom(const struct net_bridge_port *p,
struct sk_buff *skb)
{
if (nbp_switchdev_can_offload_tx_fwd(p, skb))
set_bit(p->hwdom, &BR_INPUT_SKB_CB(skb)->fwd_hwdoms);
}
void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
struct sk_buff *skb)
{
if (p->hwdom)
BR_INPUT_SKB_CB(skb)->src_hwdom = p->hwdom;
}
bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
const struct sk_buff *skb)
{
struct br_input_skb_cb *cb = BR_INPUT_SKB_CB(skb);
return !test_bit(p->hwdom, &cb->fwd_hwdoms) &&
(!skb->offload_fwd_mark || cb->src_hwdom != p->hwdom);
}
/* Flags that can be offloaded to hardware */
#define BR_PORT_FLAGS_HW_OFFLOAD (BR_LEARNING | BR_FLOOD | BR_PORT_MAB | \
BR_MCAST_FLOOD | BR_BCAST_FLOOD | BR_PORT_LOCKED | \
BR_HAIRPIN_MODE | BR_ISOLATED | BR_MULTICAST_TO_UNICAST)
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) {
NL_SET_ERR_MSG_WEAK_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, extack);
if (err) {
NL_SET_ERR_MSG_WEAK_MOD(extack,
"error setting offload flag on port");
return err;
}
return 0;
}
static void br_switchdev_fdb_populate(struct net_bridge *br,
struct switchdev_notifier_fdb_info *item,
const struct net_bridge_fdb_entry *fdb,
const void *ctx)
{
const struct net_bridge_port *p = READ_ONCE(fdb->dst);
item->addr = fdb->key.addr.addr;
item->vid = fdb->key.vlan_id;
item->added_by_user = test_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
item->offloaded = test_bit(BR_FDB_OFFLOADED, &fdb->flags);
item->is_local = test_bit(BR_FDB_LOCAL, &fdb->flags);
item->locked = false;
item->info.dev = (!p || item->is_local) ? br->dev : p->dev;
item->info.ctx = ctx;
}
void
br_switchdev_fdb_notify(struct net_bridge *br,
const struct net_bridge_fdb_entry *fdb, int type)
{
struct switchdev_notifier_fdb_info item;
if (test_bit(BR_FDB_LOCKED, &fdb->flags))
return;
/* Entries with these flags were created using ndm_state == NUD_REACHABLE,
* ndm_flags == NTF_MASTER( | NTF_STICKY), ext_flags == 0 by something
* equivalent to 'bridge fdb add ... master dynamic (sticky)'.
* Drivers don't know how to deal with these, so don't notify them to
* avoid confusing them.
*/
if (test_bit(BR_FDB_ADDED_BY_USER, &fdb->flags) &&
!test_bit(BR_FDB_STATIC, &fdb->flags) &&
!test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
return;
br_switchdev_fdb_populate(br, &item, fdb, NULL);
switch (type) {
case RTM_DELNEIGH:
call_switchdev_notifiers(SWITCHDEV_FDB_DEL_TO_DEVICE,
item.info.dev, &item.info, NULL);
break;
case RTM_NEWNEIGH:
call_switchdev_notifiers(SWITCHDEV_FDB_ADD_TO_DEVICE,
item.info.dev, &item.info, NULL);
break;
}
}
int br_switchdev_port_vlan_add(struct net_device *dev, u16 vid, u16 flags,
bool changed, 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,
.changed = changed,
};
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);
}
static int nbp_switchdev_hwdom_set(struct net_bridge_port *joining)
{
struct net_bridge *br = joining->br;
struct net_bridge_port *p;
int hwdom;
/* joining is yet to be added to the port list. */
list_for_each_entry(p, &br->port_list, list) {
if (netdev_phys_item_id_same(&joining->ppid, &p->ppid)) {
joining->hwdom = p->hwdom;
return 0;
}
}
hwdom = find_next_zero_bit(&br->busy_hwdoms, BR_HWDOM_MAX, 1);
if (hwdom >= BR_HWDOM_MAX)
return -EBUSY;
set_bit(hwdom, &br->busy_hwdoms);
joining->hwdom = hwdom;
return 0;
}
static void nbp_switchdev_hwdom_put(struct net_bridge_port *leaving)
{
struct net_bridge *br = leaving->br;
struct net_bridge_port *p;
/* leaving is no longer in the port list. */
list_for_each_entry(p, &br->port_list, list) {
if (p->hwdom == leaving->hwdom)
return;
}
clear_bit(leaving->hwdom, &br->busy_hwdoms);
}
static int nbp_switchdev_add(struct net_bridge_port *p,
struct netdev_phys_item_id ppid,
bool tx_fwd_offload,
struct netlink_ext_ack *extack)
{
int err;
if (p->offload_count) {
/* Prevent unsupported configurations such as a bridge port
* which is a bonding interface, and the member ports are from
* different hardware switches.
*/
if (!netdev_phys_item_id_same(&p->ppid, &ppid)) {
NL_SET_ERR_MSG_MOD(extack,
"Same bridge port cannot be offloaded by two physical switches");
return -EBUSY;
}
/* Tolerate drivers that call switchdev_bridge_port_offload()
* more than once for the same bridge port, such as when the
* bridge port is an offloaded bonding/team interface.
*/
p->offload_count++;
return 0;
}
p->ppid = ppid;
p->offload_count = 1;
err = nbp_switchdev_hwdom_set(p);
if (err)
return err;
if (tx_fwd_offload) {
p->flags |= BR_TX_FWD_OFFLOAD;
static_branch_inc(&br_switchdev_tx_fwd_offload);
}
return 0;
}
static void nbp_switchdev_del(struct net_bridge_port *p)
{
if (WARN_ON(!p->offload_count))
return;
p->offload_count--;
if (p->offload_count)
return;
if (p->hwdom)
nbp_switchdev_hwdom_put(p);
if (p->flags & BR_TX_FWD_OFFLOAD) {
p->flags &= ~BR_TX_FWD_OFFLOAD;
static_branch_dec(&br_switchdev_tx_fwd_offload);
}
}
static int
br_switchdev_fdb_replay_one(struct net_bridge *br, struct notifier_block *nb,
const struct net_bridge_fdb_entry *fdb,
unsigned long action, const void *ctx)
{
struct switchdev_notifier_fdb_info item;
int err;
br_switchdev_fdb_populate(br, &item, fdb, ctx);
err = nb->notifier_call(nb, action, &item);
return notifier_to_errno(err);
}
static int
br_switchdev_fdb_replay(const struct net_device *br_dev, const void *ctx,
bool adding, struct notifier_block *nb)
{
struct net_bridge_fdb_entry *fdb;
struct net_bridge *br;
unsigned long action;
int err = 0;
if (!nb)
return 0;
if (!netif_is_bridge_master(br_dev))
return -EINVAL;
br = netdev_priv(br_dev);
if (adding)
action = SWITCHDEV_FDB_ADD_TO_DEVICE;
else
action = SWITCHDEV_FDB_DEL_TO_DEVICE;
rcu_read_lock();
hlist_for_each_entry_rcu(fdb, &br->fdb_list, fdb_node) {
err = br_switchdev_fdb_replay_one(br, nb, fdb, action, ctx);
if (err)
break;
}
rcu_read_unlock();
return err;
}
static int br_switchdev_vlan_attr_replay(struct net_device *br_dev,
const void *ctx,
struct notifier_block *nb,
struct netlink_ext_ack *extack)
{
struct switchdev_notifier_port_attr_info attr_info = {
.info = {
.dev = br_dev,
.extack = extack,
.ctx = ctx,
},
};
struct net_bridge *br = netdev_priv(br_dev);
struct net_bridge_vlan_group *vg;
struct switchdev_attr attr;
struct net_bridge_vlan *v;
int err;
attr_info.attr = &attr;
attr.orig_dev = br_dev;
vg = br_vlan_group(br);
if (!vg)
return 0;
list_for_each_entry(v, &vg->vlan_list, vlist) {
if (v->msti) {
attr.id = SWITCHDEV_ATTR_ID_VLAN_MSTI;
attr.u.vlan_msti.vid = v->vid;
attr.u.vlan_msti.msti = v->msti;
err = nb->notifier_call(nb, SWITCHDEV_PORT_ATTR_SET,
&attr_info);
err = notifier_to_errno(err);
if (err)
return err;
}
}
return 0;
}
static int
br_switchdev_vlan_replay_one(struct notifier_block *nb,
struct net_device *dev,
struct switchdev_obj_port_vlan *vlan,
const void *ctx, unsigned long action,
struct netlink_ext_ack *extack)
{
struct switchdev_notifier_port_obj_info obj_info = {
.info = {
.dev = dev,
.extack = extack,
.ctx = ctx,
},
.obj = &vlan->obj,
};
int err;
err = nb->notifier_call(nb, action, &obj_info);
return notifier_to_errno(err);
}
static int br_switchdev_vlan_replay_group(struct notifier_block *nb,
struct net_device *dev,
struct net_bridge_vlan_group *vg,
const void *ctx, unsigned long action,
struct netlink_ext_ack *extack)
{
struct net_bridge_vlan *v;
int err = 0;
u16 pvid;
if (!vg)
return 0;
pvid = br_get_pvid(vg);
list_for_each_entry(v, &vg->vlan_list, vlist) {
struct switchdev_obj_port_vlan vlan = {
.obj.orig_dev = dev,
.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
.flags = br_vlan_flags(v, pvid),
.vid = v->vid,
};
if (!br_vlan_should_use(v))
continue;
err = br_switchdev_vlan_replay_one(nb, dev, &vlan, ctx,
action, extack);
if (err)
return err;
}
return 0;
}
static int br_switchdev_vlan_replay(struct net_device *br_dev,
const void *ctx, bool adding,
struct notifier_block *nb,
struct netlink_ext_ack *extack)
{
struct net_bridge *br = netdev_priv(br_dev);
struct net_bridge_port *p;
unsigned long action;
int err;
ASSERT_RTNL();
if (!nb)
return 0;
if (!netif_is_bridge_master(br_dev))
return -EINVAL;
if (adding)
action = SWITCHDEV_PORT_OBJ_ADD;
else
action = SWITCHDEV_PORT_OBJ_DEL;
err = br_switchdev_vlan_replay_group(nb, br_dev, br_vlan_group(br),
ctx, action, extack);
if (err)
return err;
list_for_each_entry(p, &br->port_list, list) {
struct net_device *dev = p->dev;
err = br_switchdev_vlan_replay_group(nb, dev,
nbp_vlan_group(p),
ctx, action, extack);
if (err)
return err;
}
if (adding) {
err = br_switchdev_vlan_attr_replay(br_dev, ctx, nb, extack);
if (err)
return err;
}
return 0;
}
#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
struct br_switchdev_mdb_complete_info {
struct net_bridge_port *port;
struct br_ip ip;
};
static void br_switchdev_mdb_complete(struct net_device *dev, int err, void *priv)
{
struct br_switchdev_mdb_complete_info *data = priv;
struct net_bridge_port_group __rcu **pp;
struct net_bridge_port_group *p;
struct net_bridge_mdb_entry *mp;
struct net_bridge_port *port = data->port;
struct net_bridge *br = port->br;
if (err)
goto err;
spin_lock_bh(&br->multicast_lock);
mp = br_mdb_ip_get(br, &data->ip);
if (!mp)
goto out;
for (pp = &mp->ports; (p = mlock_dereference(*pp, br)) != NULL;
pp = &p->next) {
if (p->key.port != port)
continue;
p->flags |= MDB_PG_FLAGS_OFFLOAD;
}
out:
spin_unlock_bh(&br->multicast_lock);
err:
kfree(priv);
}
static void br_switchdev_mdb_populate(struct switchdev_obj_port_mdb *mdb,
const struct net_bridge_mdb_entry *mp)
{
if (mp->addr.proto == htons(ETH_P_IP))
ip_eth_mc_map(mp->addr.dst.ip4, mdb->addr);
#if IS_ENABLED(CONFIG_IPV6)
else if (mp->addr.proto == htons(ETH_P_IPV6))
ipv6_eth_mc_map(&mp->addr.dst.ip6, mdb->addr);
#endif
else
ether_addr_copy(mdb->addr, mp->addr.dst.mac_addr);
mdb->vid = mp->addr.vid;
}
static void br_switchdev_host_mdb_one(struct net_device *dev,
struct net_device *lower_dev,
struct net_bridge_mdb_entry *mp,
int type)
{
struct switchdev_obj_port_mdb mdb = {
.obj = {
.id = SWITCHDEV_OBJ_ID_HOST_MDB,
.flags = SWITCHDEV_F_DEFER,
.orig_dev = dev,
},
};
br_switchdev_mdb_populate(&mdb, mp);
switch (type) {
case RTM_NEWMDB:
switchdev_port_obj_add(lower_dev, &mdb.obj, NULL);
break;
case RTM_DELMDB:
switchdev_port_obj_del(lower_dev, &mdb.obj);
break;
}
}
static void br_switchdev_host_mdb(struct net_device *dev,
struct net_bridge_mdb_entry *mp, int type)
{
struct net_device *lower_dev;
struct list_head *iter;
netdev_for_each_lower_dev(dev, lower_dev, iter)
br_switchdev_host_mdb_one(dev, lower_dev, mp, type);
}
static int
br_switchdev_mdb_replay_one(struct notifier_block *nb, struct net_device *dev,
const struct switchdev_obj_port_mdb *mdb,
unsigned long action, const void *ctx,
struct netlink_ext_ack *extack)
{
struct switchdev_notifier_port_obj_info obj_info = {
.info = {
.dev = dev,
.extack = extack,
.ctx = ctx,
},
.obj = &mdb->obj,
};
int err;
err = nb->notifier_call(nb, action, &obj_info);
return notifier_to_errno(err);
}
static int br_switchdev_mdb_queue_one(struct list_head *mdb_list,
enum switchdev_obj_id id,
const struct net_bridge_mdb_entry *mp,
struct net_device *orig_dev)
{
struct switchdev_obj_port_mdb *mdb;
mdb = kzalloc(sizeof(*mdb), GFP_ATOMIC);
if (!mdb)
return -ENOMEM;
mdb->obj.id = id;
mdb->obj.orig_dev = orig_dev;
br_switchdev_mdb_populate(mdb, mp);
list_add_tail(&mdb->obj.list, mdb_list);
return 0;
}
void br_switchdev_mdb_notify(struct net_device *dev,
struct net_bridge_mdb_entry *mp,
struct net_bridge_port_group *pg,
int type)
{
struct br_switchdev_mdb_complete_info *complete_info;
struct switchdev_obj_port_mdb mdb = {
.obj = {
.id = SWITCHDEV_OBJ_ID_PORT_MDB,
.flags = SWITCHDEV_F_DEFER,
},
};
if (!pg)
return br_switchdev_host_mdb(dev, mp, type);
br_switchdev_mdb_populate(&mdb, mp);
mdb.obj.orig_dev = pg->key.port->dev;
switch (type) {
case RTM_NEWMDB:
complete_info = kmalloc(sizeof(*complete_info), GFP_ATOMIC);
if (!complete_info)
break;
complete_info->port = pg->key.port;
complete_info->ip = mp->addr;
mdb.obj.complete_priv = complete_info;
mdb.obj.complete = br_switchdev_mdb_complete;
if (switchdev_port_obj_add(pg->key.port->dev, &mdb.obj, NULL))
kfree(complete_info);
break;
case RTM_DELMDB:
switchdev_port_obj_del(pg->key.port->dev, &mdb.obj);
break;
}
}
#endif
static int
br_switchdev_mdb_replay(struct net_device *br_dev, struct net_device *dev,
const void *ctx, bool adding, struct notifier_block *nb,
struct netlink_ext_ack *extack)
{
#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
const struct net_bridge_mdb_entry *mp;
struct switchdev_obj *obj, *tmp;
struct net_bridge *br;
unsigned long action;
LIST_HEAD(mdb_list);
int err = 0;
ASSERT_RTNL();
if (!nb)
return 0;
if (!netif_is_bridge_master(br_dev) || !netif_is_bridge_port(dev))
return -EINVAL;
br = netdev_priv(br_dev);
if (!br_opt_get(br, BROPT_MULTICAST_ENABLED))
return 0;
/* We cannot walk over br->mdb_list protected just by the rtnl_mutex,
* because the write-side protection is br->multicast_lock. But we
* need to emulate the [ blocking ] calling context of a regular
* switchdev event, so since both br->multicast_lock and RCU read side
* critical sections are atomic, we have no choice but to pick the RCU
* read side lock, queue up all our events, leave the critical section
* and notify switchdev from blocking context.
*/
rcu_read_lock();
hlist_for_each_entry_rcu(mp, &br->mdb_list, mdb_node) {
struct net_bridge_port_group __rcu * const *pp;
const struct net_bridge_port_group *p;
if (mp->host_joined) {
err = br_switchdev_mdb_queue_one(&mdb_list,
SWITCHDEV_OBJ_ID_HOST_MDB,
mp, br_dev);
if (err) {
rcu_read_unlock();
goto out_free_mdb;
}
}
for (pp = &mp->ports; (p = rcu_dereference(*pp)) != NULL;
pp = &p->next) {
if (p->key.port->dev != dev)
continue;
err = br_switchdev_mdb_queue_one(&mdb_list,
SWITCHDEV_OBJ_ID_PORT_MDB,
mp, dev);
if (err) {
rcu_read_unlock();
goto out_free_mdb;
}
}
}
rcu_read_unlock();
if (adding)
action = SWITCHDEV_PORT_OBJ_ADD;
else
action = SWITCHDEV_PORT_OBJ_DEL;
list_for_each_entry(obj, &mdb_list, list) {
err = br_switchdev_mdb_replay_one(nb, dev,
SWITCHDEV_OBJ_PORT_MDB(obj),
action, ctx, extack);
if (err)
goto out_free_mdb;
}
out_free_mdb:
list_for_each_entry_safe(obj, tmp, &mdb_list, list) {
list_del(&obj->list);
kfree(SWITCHDEV_OBJ_PORT_MDB(obj));
}
if (err)
return err;
#endif
return 0;
}
static int nbp_switchdev_sync_objs(struct net_bridge_port *p, const void *ctx,
struct notifier_block *atomic_nb,
struct notifier_block *blocking_nb,
struct netlink_ext_ack *extack)
{
struct net_device *br_dev = p->br->dev;
struct net_device *dev = p->dev;
int err;
err = br_switchdev_vlan_replay(br_dev, ctx, true, blocking_nb, extack);
if (err && err != -EOPNOTSUPP)
return err;
err = br_switchdev_mdb_replay(br_dev, dev, ctx, true, blocking_nb,
extack);
if (err && err != -EOPNOTSUPP)
return err;
err = br_switchdev_fdb_replay(br_dev, ctx, true, atomic_nb);
if (err && err != -EOPNOTSUPP)
return err;
return 0;
}
static void nbp_switchdev_unsync_objs(struct net_bridge_port *p,
const void *ctx,
struct notifier_block *atomic_nb,
struct notifier_block *blocking_nb)
{
struct net_device *br_dev = p->br->dev;
struct net_device *dev = p->dev;
br_switchdev_fdb_replay(br_dev, ctx, false, atomic_nb);
br_switchdev_mdb_replay(br_dev, dev, ctx, false, blocking_nb, NULL);
br_switchdev_vlan_replay(br_dev, ctx, false, blocking_nb, NULL);
}
/* Let the bridge know that this port is offloaded, so that it can assign a
* switchdev hardware domain to it.
*/
int br_switchdev_port_offload(struct net_bridge_port *p,
struct net_device *dev, const void *ctx,
struct notifier_block *atomic_nb,
struct notifier_block *blocking_nb,
bool tx_fwd_offload,
struct netlink_ext_ack *extack)
{
struct netdev_phys_item_id ppid;
int err;
err = dev_get_port_parent_id(dev, &ppid, false);
if (err)
return err;
err = nbp_switchdev_add(p, ppid, tx_fwd_offload, extack);
if (err)
return err;
err = nbp_switchdev_sync_objs(p, ctx, atomic_nb, blocking_nb, extack);
if (err)
goto out_switchdev_del;
return 0;
out_switchdev_del:
nbp_switchdev_del(p);
return err;
}
void br_switchdev_port_unoffload(struct net_bridge_port *p, const void *ctx,
struct notifier_block *atomic_nb,
struct notifier_block *blocking_nb)
{
nbp_switchdev_unsync_objs(p, ctx, atomic_nb, blocking_nb);
nbp_switchdev_del(p);
}