Re: [PATCH net-next] net: bridge: use device address list insteadof dev_addr (repost)

From: Eric Dumazet
Date: Wed May 06 2009 - 11:14:25 EST


Jiri Pirko a écrit :
> (repost, no modifications)

Well, some changes are welcome :)

>
> This patch changes the handling of mac addresses of bridge port devices. Now
> it uses previously introduced list of device addresses. It allows the bridge to
> know more then one local mac address per port which is mandatory for the right
> work in some cases.
>
> Signed-off-by: Jiri Pirko <jpirko@xxxxxxxxxx>
> ---
> net/bridge/br_fdb.c | 101 ++++++++++++++++++++++++++++++----------------
> net/bridge/br_if.c | 2 +-
> net/bridge/br_notify.c | 2 +-
> net/bridge/br_private.h | 4 +-
> 4 files changed, 70 insertions(+), 39 deletions(-)
>
> diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
> index a48f5ef..1e63f76 100644
> --- a/net/bridge/br_fdb.c
> +++ b/net/bridge/br_fdb.c
> @@ -77,10 +77,26 @@ static inline void fdb_delete(struct net_bridge_fdb_entry *f)
> br_fdb_put(f);
> }
>
> -void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
> +static bool another_port_has_addr(const struct net_bridge_port *p,
> + struct net_bridge_fdb_entry *f)
> +{
> + struct net_bridge *br = p->br;
> + struct net_bridge_port *op;
> +
> + list_for_each_entry(op, &br->port_list, list) {
> + if (op != p && is_etherdev_addr(op->dev, f->addr.addr)) {
> + f->dst = op;
> + return 1;
> + }
> + }
> + return 0;
> +}
> +
> +void br_fdb_changeaddr(struct net_bridge_port *p, struct net_device *dev)
> {
> struct net_bridge *br = p->br;
> int i;
> + struct netdev_hw_addr *ha;
>
> spin_lock_bh(&br->hash_lock);
>
> @@ -92,26 +108,23 @@ void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
>
> f = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
> if (f->dst == p && f->is_local) {
> - /* maybe another port has same hw addr? */
> - struct net_bridge_port *op;
> - list_for_each_entry(op, &br->port_list, list) {
> - if (op != p &&
> - !compare_ether_addr(op->dev->dev_addr,
> - f->addr.addr)) {
> - f->dst = op;
> - goto insert;
> - }
> - }
> -
> - /* delete old one */
> - fdb_delete(f);
> - goto insert;
> + /*
> + * maybe another port has same hw addr?,
> + * if not then delete it
> + */
> + if (!another_port_has_addr(p, f))
> + fdb_delete(f);
> }
> }
> }
> - insert:
> - /* insert new address, may fail if invalid address or dup. */
> - fdb_insert(br, p, newaddr);
> +
> + /* insert device addresses, may fail if invalid address. */
> +
> + rcu_read_lock();

Same problem than a previous patch Jiri.

You should not use rcu_read_lock()/rcu_read_unlock() at all in this context,
since you already own a lock.


> + for_each_dev_addr(dev, ha) {
> + fdb_insert(br, p, ha->addr);
> + }
> + rcu_read_unlock();
>
> spin_unlock_bh(&br->hash_lock);
> }
> @@ -189,20 +202,9 @@ void br_fdb_delete_by_port(struct net_bridge *br,
> * then when one port is deleted, assign
> * the local entry to other port
> */
> - if (f->is_local) {
> - struct net_bridge_port *op;
> - list_for_each_entry(op, &br->port_list, list) {
> - if (op != p &&
> - !compare_ether_addr(op->dev->dev_addr,
> - f->addr.addr)) {
> - f->dst = op;
> - goto skip_delete;
> - }
> - }
> - }
> -
> - fdb_delete(f);
> - skip_delete: ;
> + if (!f->is_local ||
> + !another_port_has_addr(p, f))
> + fdb_delete(f);
> }
> }
> spin_unlock_bh(&br->hash_lock);
> @@ -338,7 +340,7 @@ static struct net_bridge_fdb_entry *fdb_create(struct hlist_head *head,
> }
>
> static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
> - const unsigned char *addr)
> + const unsigned char *addr)
> {
> struct hlist_head *head = &br->hash[br_mac_hash(addr)];
> struct net_bridge_fdb_entry *fdb;
> @@ -366,13 +368,42 @@ static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
> return 0;
> }
>
> +static int fdb_insert_dev(struct net_bridge *br, struct net_bridge_port *source,
> + struct net_device *dev)
> +{
> + struct netdev_hw_addr *ha, *ha2;
> + struct net_bridge_fdb_entry *fdb;
> + struct hlist_head *head;
> + int ret = 0;
> +
> + rcu_read_lock();


You should not use rcu_read_lock()/rcu_read_unlock() at all in this context


> + for_each_dev_addr(dev, ha) {
> + ret = fdb_insert(br, source, ha->addr);
> + if (ret)
> + goto unroll;
> + }
> + goto unlock;
> +unroll:
> + for_each_dev_addr(dev, ha2) {
> + if (ha2 == ha)
> + break;
> + head = &br->hash[br_mac_hash(ha2->addr)];
> + fdb = fdb_find(head, ha2->addr);
> + if (fdb && fdb->is_local)
> + fdb_delete(fdb);
> + }
> +unlock:
> + rcu_read_unlock();
> + return ret;
> +}
> +
> int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
> - const unsigned char *addr)
> + struct net_device *dev)
> {
> int ret;
>
> spin_lock_bh(&br->hash_lock);
> - ret = fdb_insert(br, source, addr);
> + ret = fdb_insert_dev(br, source, dev);
> spin_unlock_bh(&br->hash_lock);
> return ret;
> }
> diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
> index 8a96672..789cb30 100644
> --- a/net/bridge/br_if.c
> +++ b/net/bridge/br_if.c
> @@ -392,7 +392,7 @@ int br_add_if(struct net_bridge *br, struct net_device *dev)
> if (err)
> goto err0;
>
> - err = br_fdb_insert(br, p, dev->dev_addr);
> + err = br_fdb_insert(br, p, dev);
> if (err)
> goto err1;
>
> diff --git a/net/bridge/br_notify.c b/net/bridge/br_notify.c
> index 763a3ec..1423541 100644
> --- a/net/bridge/br_notify.c
> +++ b/net/bridge/br_notify.c
> @@ -48,7 +48,7 @@ static int br_device_event(struct notifier_block *unused, unsigned long event, v
>
> case NETDEV_CHANGEADDR:
> spin_lock_bh(&br->lock);
> - br_fdb_changeaddr(p, dev->dev_addr);
> + br_fdb_changeaddr(p, dev);
> br_stp_recalculate_bridge_id(br);
> spin_unlock_bh(&br->lock);
> break;
> diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
> index b6c3b71..65ffe3d 100644
> --- a/net/bridge/br_private.h
> +++ b/net/bridge/br_private.h
> @@ -148,7 +148,7 @@ extern int br_fdb_init(void);
> extern void br_fdb_fini(void);
> extern void br_fdb_flush(struct net_bridge *br);
> extern void br_fdb_changeaddr(struct net_bridge_port *p,
> - const unsigned char *newaddr);
> + struct net_device *dev);
> extern void br_fdb_cleanup(unsigned long arg);
> extern void br_fdb_delete_by_port(struct net_bridge *br,
> const struct net_bridge_port *p, int do_all);
> @@ -161,7 +161,7 @@ extern int br_fdb_fillbuf(struct net_bridge *br, void *buf,
> unsigned long count, unsigned long off);
> extern int br_fdb_insert(struct net_bridge *br,
> struct net_bridge_port *source,
> - const unsigned char *addr);
> + struct net_device *dev);
> extern void br_fdb_update(struct net_bridge *br,
> struct net_bridge_port *source,
> const unsigned char *addr);
>
>


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