linux/net/bridge/br_vlan.c
Toshiaki Makita bdf4351bbc bridge: Remove unnecessary vlan_put_tag in br_handle_vlan
br_handle_vlan() pushes HW accelerated vlan tag into skbuff when outgoing
port is the bridge device.
This is unnecessary because __netif_receive_skb_core() can handle skbs
with HW accelerated vlan tag. In current implementation,
__netif_receive_skb_core() needs to extract the vlan tag embedded in skb
data. This could cause low network performance especially when receiving
frames at a high frame rate on the bridge device.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 21:29:27 -08:00

404 lines
7.8 KiB
C

#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/slab.h>
#include "br_private.h"
static void __vlan_add_pvid(struct net_port_vlans *v, u16 vid)
{
if (v->pvid == vid)
return;
smp_wmb();
v->pvid = vid;
}
static void __vlan_delete_pvid(struct net_port_vlans *v, u16 vid)
{
if (v->pvid != vid)
return;
smp_wmb();
v->pvid = 0;
}
static void __vlan_add_flags(struct net_port_vlans *v, u16 vid, u16 flags)
{
if (flags & BRIDGE_VLAN_INFO_PVID)
__vlan_add_pvid(v, vid);
if (flags & BRIDGE_VLAN_INFO_UNTAGGED)
set_bit(vid, v->untagged_bitmap);
}
static int __vlan_add(struct net_port_vlans *v, u16 vid, u16 flags)
{
struct net_bridge_port *p = NULL;
struct net_bridge *br;
struct net_device *dev;
int err;
if (test_bit(vid, v->vlan_bitmap)) {
__vlan_add_flags(v, vid, flags);
return 0;
}
if (v->port_idx) {
p = v->parent.port;
br = p->br;
dev = p->dev;
} else {
br = v->parent.br;
dev = br->dev;
}
if (p) {
/* Add VLAN to the device filter if it is supported.
* Stricly speaking, this is not necessary now, since
* devices are made promiscuous by the bridge, but if
* that ever changes this code will allow tagged
* traffic to enter the bridge.
*/
err = vlan_vid_add(dev, htons(ETH_P_8021Q), vid);
if (err)
return err;
}
err = br_fdb_insert(br, p, dev->dev_addr, vid);
if (err) {
br_err(br, "failed insert local address into bridge "
"forwarding table\n");
goto out_filt;
}
set_bit(vid, v->vlan_bitmap);
v->num_vlans++;
__vlan_add_flags(v, vid, flags);
return 0;
out_filt:
if (p)
vlan_vid_del(dev, htons(ETH_P_8021Q), vid);
return err;
}
static int __vlan_del(struct net_port_vlans *v, u16 vid)
{
if (!test_bit(vid, v->vlan_bitmap))
return -EINVAL;
__vlan_delete_pvid(v, vid);
clear_bit(vid, v->untagged_bitmap);
if (v->port_idx)
vlan_vid_del(v->parent.port->dev, htons(ETH_P_8021Q), vid);
clear_bit(vid, v->vlan_bitmap);
v->num_vlans--;
if (bitmap_empty(v->vlan_bitmap, VLAN_N_VID)) {
if (v->port_idx)
rcu_assign_pointer(v->parent.port->vlan_info, NULL);
else
rcu_assign_pointer(v->parent.br->vlan_info, NULL);
kfree_rcu(v, rcu);
}
return 0;
}
static void __vlan_flush(struct net_port_vlans *v)
{
smp_wmb();
v->pvid = 0;
bitmap_zero(v->vlan_bitmap, VLAN_N_VID);
if (v->port_idx)
rcu_assign_pointer(v->parent.port->vlan_info, NULL);
else
rcu_assign_pointer(v->parent.br->vlan_info, NULL);
kfree_rcu(v, rcu);
}
/* Strip the tag from the packet. Will return skb with tci set 0. */
static struct sk_buff *br_vlan_untag(struct sk_buff *skb)
{
if (skb->protocol != htons(ETH_P_8021Q)) {
skb->vlan_tci = 0;
return skb;
}
skb->vlan_tci = 0;
skb = vlan_untag(skb);
if (skb)
skb->vlan_tci = 0;
return skb;
}
struct sk_buff *br_handle_vlan(struct net_bridge *br,
const struct net_port_vlans *pv,
struct sk_buff *skb)
{
u16 vid;
if (!br->vlan_enabled)
goto out;
/* At this point, we know that the frame was filtered and contains
* a valid vlan id. If the vlan id is set in the untagged bitmap,
* send untagged; otherwise, send tagged.
*/
br_vlan_get_tag(skb, &vid);
if (test_bit(vid, pv->untagged_bitmap))
skb = br_vlan_untag(skb);
out:
return skb;
}
/* Called under RCU */
bool br_allowed_ingress(struct net_bridge *br, struct net_port_vlans *v,
struct sk_buff *skb, u16 *vid)
{
int err;
/* If VLAN filtering is disabled on the bridge, all packets are
* permitted.
*/
if (!br->vlan_enabled)
return true;
/* If there are no vlan in the permitted list, all packets are
* rejected.
*/
if (!v)
return false;
err = br_vlan_get_tag(skb, vid);
if (!*vid) {
u16 pvid = br_get_pvid(v);
/* Frame had a tag with VID 0 or did not have a tag.
* See if pvid is set on this port. That tells us which
* vlan untagged or priority-tagged traffic belongs to.
*/
if (pvid == VLAN_N_VID)
return false;
/* PVID is set on this port. Any untagged or priority-tagged
* ingress frame is considered to belong to this vlan.
*/
*vid = pvid;
if (likely(err))
/* Untagged Frame. */
__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), pvid);
else
/* Priority-tagged Frame.
* At this point, We know that skb->vlan_tci had
* VLAN_TAG_PRESENT bit and its VID field was 0x000.
* We update only VID field and preserve PCP field.
*/
skb->vlan_tci |= pvid;
return true;
}
/* Frame had a valid vlan tag. See if vlan is allowed */
if (test_bit(*vid, v->vlan_bitmap))
return true;
return false;
}
/* Called under RCU. */
bool br_allowed_egress(struct net_bridge *br,
const struct net_port_vlans *v,
const struct sk_buff *skb)
{
u16 vid;
if (!br->vlan_enabled)
return true;
if (!v)
return false;
br_vlan_get_tag(skb, &vid);
if (test_bit(vid, v->vlan_bitmap))
return true;
return false;
}
/* Must be protected by RTNL.
* Must be called with vid in range from 1 to 4094 inclusive.
*/
int br_vlan_add(struct net_bridge *br, u16 vid, u16 flags)
{
struct net_port_vlans *pv = NULL;
int err;
ASSERT_RTNL();
pv = rtnl_dereference(br->vlan_info);
if (pv)
return __vlan_add(pv, vid, flags);
/* Create port vlan infomration
*/
pv = kzalloc(sizeof(*pv), GFP_KERNEL);
if (!pv)
return -ENOMEM;
pv->parent.br = br;
err = __vlan_add(pv, vid, flags);
if (err)
goto out;
rcu_assign_pointer(br->vlan_info, pv);
return 0;
out:
kfree(pv);
return err;
}
/* Must be protected by RTNL.
* Must be called with vid in range from 1 to 4094 inclusive.
*/
int br_vlan_delete(struct net_bridge *br, u16 vid)
{
struct net_port_vlans *pv;
ASSERT_RTNL();
pv = rtnl_dereference(br->vlan_info);
if (!pv)
return -EINVAL;
spin_lock_bh(&br->hash_lock);
fdb_delete_by_addr(br, br->dev->dev_addr, vid);
spin_unlock_bh(&br->hash_lock);
__vlan_del(pv, vid);
return 0;
}
void br_vlan_flush(struct net_bridge *br)
{
struct net_port_vlans *pv;
ASSERT_RTNL();
pv = rtnl_dereference(br->vlan_info);
if (!pv)
return;
__vlan_flush(pv);
}
int br_vlan_filter_toggle(struct net_bridge *br, unsigned long val)
{
if (!rtnl_trylock())
return restart_syscall();
if (br->vlan_enabled == val)
goto unlock;
br->vlan_enabled = val;
unlock:
rtnl_unlock();
return 0;
}
/* Must be protected by RTNL.
* Must be called with vid in range from 1 to 4094 inclusive.
*/
int nbp_vlan_add(struct net_bridge_port *port, u16 vid, u16 flags)
{
struct net_port_vlans *pv = NULL;
int err;
ASSERT_RTNL();
pv = rtnl_dereference(port->vlan_info);
if (pv)
return __vlan_add(pv, vid, flags);
/* Create port vlan infomration
*/
pv = kzalloc(sizeof(*pv), GFP_KERNEL);
if (!pv) {
err = -ENOMEM;
goto clean_up;
}
pv->port_idx = port->port_no;
pv->parent.port = port;
err = __vlan_add(pv, vid, flags);
if (err)
goto clean_up;
rcu_assign_pointer(port->vlan_info, pv);
return 0;
clean_up:
kfree(pv);
return err;
}
/* Must be protected by RTNL.
* Must be called with vid in range from 1 to 4094 inclusive.
*/
int nbp_vlan_delete(struct net_bridge_port *port, u16 vid)
{
struct net_port_vlans *pv;
ASSERT_RTNL();
pv = rtnl_dereference(port->vlan_info);
if (!pv)
return -EINVAL;
spin_lock_bh(&port->br->hash_lock);
fdb_delete_by_addr(port->br, port->dev->dev_addr, vid);
spin_unlock_bh(&port->br->hash_lock);
return __vlan_del(pv, vid);
}
void nbp_vlan_flush(struct net_bridge_port *port)
{
struct net_port_vlans *pv;
u16 vid;
ASSERT_RTNL();
pv = rtnl_dereference(port->vlan_info);
if (!pv)
return;
for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID)
vlan_vid_del(port->dev, htons(ETH_P_8021Q), vid);
__vlan_flush(pv);
}
bool nbp_vlan_find(struct net_bridge_port *port, u16 vid)
{
struct net_port_vlans *pv;
bool found = false;
rcu_read_lock();
pv = rcu_dereference(port->vlan_info);
if (!pv)
goto out;
if (test_bit(vid, pv->vlan_bitmap))
found = true;
out:
rcu_read_unlock();
return found;
}