linux/net/8021q/vlan_core.c

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#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if_vlan.h>
#include <linux/netpoll.h>
#include <linux/export.h>
#include "vlan.h"
bool vlan_do_receive(struct sk_buff **skbp)
{
vlan: Centralize handling of hardware acceleration. Currently each driver that is capable of vlan hardware acceleration must be aware of the vlan groups that are configured and then pass the stripped tag to a specialized receive function. This is different from other types of hardware offload in that it places a significant amount of knowledge in the driver itself rather keeping it in the networking core. This makes vlan offloading function more similarly to other forms of offloading (such as checksum offloading or TSO) by doing the following: * On receive, stripped vlans are passed directly to the network core, without attempting to check for vlan groups or reconstructing the header if no group * vlans are made less special by folding the logic into the main receive routines * On transmit, the device layer will add the vlan header in software if the hardware doesn't support it, instead of spreading that logic out in upper layers, such as bonding. There are a number of advantages to this: * Fixes all bugs with drivers incorrectly dropping vlan headers at once. * Avoids having to disable VLAN acceleration when in promiscuous mode (good for bridging since it always puts devices in promiscuous mode). * Keeps VLAN tag separate until given to ultimate consumer, which avoids needing to do header reconstruction as in tg3 unless absolutely necessary. * Consolidates common code in core networking. Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-20 15:56:06 +02:00
struct sk_buff *skb = *skbp;
__be16 vlan_proto = skb->vlan_proto;
u16 vlan_id = vlan_tx_tag_get_id(skb);
struct net_device *vlan_dev;
struct vlan_pcpu_stats *rx_stats;
vlan_dev = vlan_find_dev(skb->dev, vlan_proto, vlan_id);
if (!vlan_dev)
vlan: Centralize handling of hardware acceleration. Currently each driver that is capable of vlan hardware acceleration must be aware of the vlan groups that are configured and then pass the stripped tag to a specialized receive function. This is different from other types of hardware offload in that it places a significant amount of knowledge in the driver itself rather keeping it in the networking core. This makes vlan offloading function more similarly to other forms of offloading (such as checksum offloading or TSO) by doing the following: * On receive, stripped vlans are passed directly to the network core, without attempting to check for vlan groups or reconstructing the header if no group * vlans are made less special by folding the logic into the main receive routines * On transmit, the device layer will add the vlan header in software if the hardware doesn't support it, instead of spreading that logic out in upper layers, such as bonding. There are a number of advantages to this: * Fixes all bugs with drivers incorrectly dropping vlan headers at once. * Avoids having to disable VLAN acceleration when in promiscuous mode (good for bridging since it always puts devices in promiscuous mode). * Keeps VLAN tag separate until given to ultimate consumer, which avoids needing to do header reconstruction as in tg3 unless absolutely necessary. * Consolidates common code in core networking. Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-20 15:56:06 +02:00
return false;
vlan: Centralize handling of hardware acceleration. Currently each driver that is capable of vlan hardware acceleration must be aware of the vlan groups that are configured and then pass the stripped tag to a specialized receive function. This is different from other types of hardware offload in that it places a significant amount of knowledge in the driver itself rather keeping it in the networking core. This makes vlan offloading function more similarly to other forms of offloading (such as checksum offloading or TSO) by doing the following: * On receive, stripped vlans are passed directly to the network core, without attempting to check for vlan groups or reconstructing the header if no group * vlans are made less special by folding the logic into the main receive routines * On transmit, the device layer will add the vlan header in software if the hardware doesn't support it, instead of spreading that logic out in upper layers, such as bonding. There are a number of advantages to this: * Fixes all bugs with drivers incorrectly dropping vlan headers at once. * Avoids having to disable VLAN acceleration when in promiscuous mode (good for bridging since it always puts devices in promiscuous mode). * Keeps VLAN tag separate until given to ultimate consumer, which avoids needing to do header reconstruction as in tg3 unless absolutely necessary. * Consolidates common code in core networking. Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-20 15:56:06 +02:00
skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
if (unlikely(!skb))
return false;
vlan: Centralize handling of hardware acceleration. Currently each driver that is capable of vlan hardware acceleration must be aware of the vlan groups that are configured and then pass the stripped tag to a specialized receive function. This is different from other types of hardware offload in that it places a significant amount of knowledge in the driver itself rather keeping it in the networking core. This makes vlan offloading function more similarly to other forms of offloading (such as checksum offloading or TSO) by doing the following: * On receive, stripped vlans are passed directly to the network core, without attempting to check for vlan groups or reconstructing the header if no group * vlans are made less special by folding the logic into the main receive routines * On transmit, the device layer will add the vlan header in software if the hardware doesn't support it, instead of spreading that logic out in upper layers, such as bonding. There are a number of advantages to this: * Fixes all bugs with drivers incorrectly dropping vlan headers at once. * Avoids having to disable VLAN acceleration when in promiscuous mode (good for bridging since it always puts devices in promiscuous mode). * Keeps VLAN tag separate until given to ultimate consumer, which avoids needing to do header reconstruction as in tg3 unless absolutely necessary. * Consolidates common code in core networking. Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-20 15:56:06 +02:00
skb->dev = vlan_dev;
if (skb->pkt_type == PACKET_OTHERHOST) {
/* Our lower layer thinks this is not local, let's make sure.
* This allows the VLAN to have a different MAC than the
* underlying device, and still route correctly. */
if (ether_addr_equal(eth_hdr(skb)->h_dest, vlan_dev->dev_addr))
skb->pkt_type = PACKET_HOST;
}
if (!(vlan_dev_priv(vlan_dev)->flags & VLAN_FLAG_REORDER_HDR)) {
unsigned int offset = skb->data - skb_mac_header(skb);
/*
* vlan_insert_tag expect skb->data pointing to mac header.
* So change skb->data before calling it and change back to
* original position later
*/
skb_push(skb, offset);
skb = *skbp = vlan_insert_tag(skb, skb->vlan_proto,
skb->vlan_tci);
if (!skb)
return false;
skb_pull(skb, offset + VLAN_HLEN);
skb_reset_mac_len(skb);
}
vlan: Centralize handling of hardware acceleration. Currently each driver that is capable of vlan hardware acceleration must be aware of the vlan groups that are configured and then pass the stripped tag to a specialized receive function. This is different from other types of hardware offload in that it places a significant amount of knowledge in the driver itself rather keeping it in the networking core. This makes vlan offloading function more similarly to other forms of offloading (such as checksum offloading or TSO) by doing the following: * On receive, stripped vlans are passed directly to the network core, without attempting to check for vlan groups or reconstructing the header if no group * vlans are made less special by folding the logic into the main receive routines * On transmit, the device layer will add the vlan header in software if the hardware doesn't support it, instead of spreading that logic out in upper layers, such as bonding. There are a number of advantages to this: * Fixes all bugs with drivers incorrectly dropping vlan headers at once. * Avoids having to disable VLAN acceleration when in promiscuous mode (good for bridging since it always puts devices in promiscuous mode). * Keeps VLAN tag separate until given to ultimate consumer, which avoids needing to do header reconstruction as in tg3 unless absolutely necessary. * Consolidates common code in core networking. Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-20 15:56:06 +02:00
skb->priority = vlan_get_ingress_priority(vlan_dev, skb->vlan_tci);
skb->vlan_tci = 0;
rx_stats = this_cpu_ptr(vlan_dev_priv(vlan_dev)->vlan_pcpu_stats);
u64_stats_update_begin(&rx_stats->syncp);
rx_stats->rx_packets++;
rx_stats->rx_bytes += skb->len;
if (skb->pkt_type == PACKET_MULTICAST)
rx_stats->rx_multicast++;
u64_stats_update_end(&rx_stats->syncp);
vlan: Centralize handling of hardware acceleration. Currently each driver that is capable of vlan hardware acceleration must be aware of the vlan groups that are configured and then pass the stripped tag to a specialized receive function. This is different from other types of hardware offload in that it places a significant amount of knowledge in the driver itself rather keeping it in the networking core. This makes vlan offloading function more similarly to other forms of offloading (such as checksum offloading or TSO) by doing the following: * On receive, stripped vlans are passed directly to the network core, without attempting to check for vlan groups or reconstructing the header if no group * vlans are made less special by folding the logic into the main receive routines * On transmit, the device layer will add the vlan header in software if the hardware doesn't support it, instead of spreading that logic out in upper layers, such as bonding. There are a number of advantages to this: * Fixes all bugs with drivers incorrectly dropping vlan headers at once. * Avoids having to disable VLAN acceleration when in promiscuous mode (good for bridging since it always puts devices in promiscuous mode). * Keeps VLAN tag separate until given to ultimate consumer, which avoids needing to do header reconstruction as in tg3 unless absolutely necessary. * Consolidates common code in core networking. Signed-off-by: Jesse Gross <jesse@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-20 15:56:06 +02:00
return true;
}
/* Must be invoked with rcu_read_lock. */
struct net_device *__vlan_find_dev_deep(struct net_device *dev,
__be16 vlan_proto, u16 vlan_id)
{
struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info);
if (vlan_info) {
return vlan_group_get_device(&vlan_info->grp,
vlan_proto, vlan_id);
} else {
/*
* Lower devices of master uppers (bonding, team) do not have
* grp assigned to themselves. Grp is assigned to upper device
* instead.
*/
struct net_device *upper_dev;
upper_dev = netdev_master_upper_dev_get_rcu(dev);
if (upper_dev)
return __vlan_find_dev_deep(upper_dev,
vlan_proto, vlan_id);
}
return NULL;
}
EXPORT_SYMBOL(__vlan_find_dev_deep);
struct net_device *vlan_dev_real_dev(const struct net_device *dev)
{
struct net_device *ret = vlan_dev_priv(dev)->real_dev;
while (is_vlan_dev(ret))
ret = vlan_dev_priv(ret)->real_dev;
return ret;
}
EXPORT_SYMBOL(vlan_dev_real_dev);
u16 vlan_dev_vlan_id(const struct net_device *dev)
{
return vlan_dev_priv(dev)->vlan_id;
}
EXPORT_SYMBOL(vlan_dev_vlan_id);
static struct sk_buff *vlan_reorder_header(struct sk_buff *skb)
{
if (skb_cow(skb, skb_headroom(skb)) < 0)
return NULL;
memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 2 * ETH_ALEN);
skb->mac_header += VLAN_HLEN;
return skb;
}
struct sk_buff *vlan_untag(struct sk_buff *skb)
{
struct vlan_hdr *vhdr;
u16 vlan_tci;
if (unlikely(vlan_tx_tag_present(skb))) {
/* vlan_tci is already set-up so leave this for another time */
return skb;
}
skb = skb_share_check(skb, GFP_ATOMIC);
if (unlikely(!skb))
goto err_free;
if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
goto err_free;
vhdr = (struct vlan_hdr *) skb->data;
vlan_tci = ntohs(vhdr->h_vlan_TCI);
__vlan_hwaccel_put_tag(skb, skb->protocol, vlan_tci);
skb_pull_rcsum(skb, VLAN_HLEN);
vlan_set_encap_proto(skb, vhdr);
skb = vlan_reorder_header(skb);
if (unlikely(!skb))
goto err_free;
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
skb_reset_mac_len(skb);
return skb;
err_free:
kfree_skb(skb);
return NULL;
}
EXPORT_SYMBOL(vlan_untag);
/*
* vlan info and vid list
*/
static void vlan_group_free(struct vlan_group *grp)
{
int i, j;
for (i = 0; i < VLAN_PROTO_NUM; i++)
for (j = 0; j < VLAN_GROUP_ARRAY_SPLIT_PARTS; j++)
kfree(grp->vlan_devices_arrays[i][j]);
}
static void vlan_info_free(struct vlan_info *vlan_info)
{
vlan_group_free(&vlan_info->grp);
kfree(vlan_info);
}
static void vlan_info_rcu_free(struct rcu_head *rcu)
{
vlan_info_free(container_of(rcu, struct vlan_info, rcu));
}
static struct vlan_info *vlan_info_alloc(struct net_device *dev)
{
struct vlan_info *vlan_info;
vlan_info = kzalloc(sizeof(struct vlan_info), GFP_KERNEL);
if (!vlan_info)
return NULL;
vlan_info->real_dev = dev;
INIT_LIST_HEAD(&vlan_info->vid_list);
return vlan_info;
}
struct vlan_vid_info {
struct list_head list;
__be16 proto;
u16 vid;
int refcount;
};
static bool vlan_hw_filter_capable(const struct net_device *dev,
const struct vlan_vid_info *vid_info)
{
if (vid_info->proto == htons(ETH_P_8021Q) &&
dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
return true;
if (vid_info->proto == htons(ETH_P_8021AD) &&
dev->features & NETIF_F_HW_VLAN_STAG_FILTER)
return true;
return false;
}
static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info,
__be16 proto, u16 vid)
{
struct vlan_vid_info *vid_info;
list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
if (vid_info->proto == proto && vid_info->vid == vid)
return vid_info;
}
return NULL;
}
static struct vlan_vid_info *vlan_vid_info_alloc(__be16 proto, u16 vid)
{
struct vlan_vid_info *vid_info;
vid_info = kzalloc(sizeof(struct vlan_vid_info), GFP_KERNEL);
if (!vid_info)
return NULL;
vid_info->proto = proto;
vid_info->vid = vid;
return vid_info;
}
static int __vlan_vid_add(struct vlan_info *vlan_info, __be16 proto, u16 vid,
struct vlan_vid_info **pvid_info)
{
struct net_device *dev = vlan_info->real_dev;
const struct net_device_ops *ops = dev->netdev_ops;
struct vlan_vid_info *vid_info;
int err;
vid_info = vlan_vid_info_alloc(proto, vid);
if (!vid_info)
return -ENOMEM;
if (vlan_hw_filter_capable(dev, vid_info)) {
err = ops->ndo_vlan_rx_add_vid(dev, proto, vid);
if (err) {
kfree(vid_info);
return err;
}
}
list_add(&vid_info->list, &vlan_info->vid_list);
vlan_info->nr_vids++;
*pvid_info = vid_info;
return 0;
}
int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
{
struct vlan_info *vlan_info;
struct vlan_vid_info *vid_info;
bool vlan_info_created = false;
int err;
ASSERT_RTNL();
vlan_info = rtnl_dereference(dev->vlan_info);
if (!vlan_info) {
vlan_info = vlan_info_alloc(dev);
if (!vlan_info)
return -ENOMEM;
vlan_info_created = true;
}
vid_info = vlan_vid_info_get(vlan_info, proto, vid);
if (!vid_info) {
err = __vlan_vid_add(vlan_info, proto, vid, &vid_info);
if (err)
goto out_free_vlan_info;
}
vid_info->refcount++;
if (vlan_info_created)
rcu_assign_pointer(dev->vlan_info, vlan_info);
return 0;
out_free_vlan_info:
if (vlan_info_created)
kfree(vlan_info);
return err;
}
EXPORT_SYMBOL(vlan_vid_add);
static void __vlan_vid_del(struct vlan_info *vlan_info,
struct vlan_vid_info *vid_info)
{
struct net_device *dev = vlan_info->real_dev;
const struct net_device_ops *ops = dev->netdev_ops;
__be16 proto = vid_info->proto;
u16 vid = vid_info->vid;
int err;
if (vlan_hw_filter_capable(dev, vid_info)) {
err = ops->ndo_vlan_rx_kill_vid(dev, proto, vid);
if (err) {
pr_warn("failed to kill vid %04x/%d for device %s\n",
proto, vid, dev->name);
}
}
list_del(&vid_info->list);
kfree(vid_info);
vlan_info->nr_vids--;
}
void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
{
struct vlan_info *vlan_info;
struct vlan_vid_info *vid_info;
ASSERT_RTNL();
vlan_info = rtnl_dereference(dev->vlan_info);
if (!vlan_info)
return;
vid_info = vlan_vid_info_get(vlan_info, proto, vid);
if (!vid_info)
return;
vid_info->refcount--;
if (vid_info->refcount == 0) {
__vlan_vid_del(vlan_info, vid_info);
if (vlan_info->nr_vids == 0) {
RCU_INIT_POINTER(dev->vlan_info, NULL);
call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
}
}
}
EXPORT_SYMBOL(vlan_vid_del);
int vlan_vids_add_by_dev(struct net_device *dev,
const struct net_device *by_dev)
{
struct vlan_vid_info *vid_info;
struct vlan_info *vlan_info;
int err;
ASSERT_RTNL();
vlan_info = rtnl_dereference(by_dev->vlan_info);
if (!vlan_info)
return 0;
list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
err = vlan_vid_add(dev, vid_info->proto, vid_info->vid);
if (err)
goto unwind;
}
return 0;
unwind:
list_for_each_entry_continue_reverse(vid_info,
&vlan_info->vid_list,
list) {
vlan_vid_del(dev, vid_info->proto, vid_info->vid);
}
return err;
}
EXPORT_SYMBOL(vlan_vids_add_by_dev);
void vlan_vids_del_by_dev(struct net_device *dev,
const struct net_device *by_dev)
{
struct vlan_vid_info *vid_info;
struct vlan_info *vlan_info;
ASSERT_RTNL();
vlan_info = rtnl_dereference(by_dev->vlan_info);
if (!vlan_info)
return;
list_for_each_entry(vid_info, &vlan_info->vid_list, list)
vlan_vid_del(dev, vid_info->proto, vid_info->vid);
}
EXPORT_SYMBOL(vlan_vids_del_by_dev);
bool vlan_uses_dev(const struct net_device *dev)
{
struct vlan_info *vlan_info;
ASSERT_RTNL();
vlan_info = rtnl_dereference(dev->vlan_info);
if (!vlan_info)
return false;
return vlan_info->grp.nr_vlan_devs ? true : false;
}
EXPORT_SYMBOL(vlan_uses_dev);