linux/net/8021q/vlan_core.c
Dan Carpenter f9586f79bf vlan: add rtnl_dereference() annotations
The original code generates a Sparse warning:
net/8021q/vlan_core.c:336:9:
	error: incompatible types in comparison expression (different address spaces)

It's ok to dereference __rcu pointers here because we are holding the
RTNL lock.  I've added some calls to rtnl_dereference() to silence the
warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-14 02:39:30 -05:00

372 lines
8.3 KiB
C

#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, bool last_handler)
{
struct sk_buff *skb = *skbp;
u16 vlan_id = skb->vlan_tci & VLAN_VID_MASK;
struct net_device *vlan_dev;
struct vlan_pcpu_stats *rx_stats;
vlan_dev = vlan_find_dev(skb->dev, vlan_id);
if (!vlan_dev) {
/* Only the last call to vlan_do_receive() should change
* pkt_type to PACKET_OTHERHOST
*/
if (vlan_id && last_handler)
skb->pkt_type = PACKET_OTHERHOST;
return false;
}
skb = *skbp = skb_share_check(skb, GFP_ATOMIC);
if (unlikely(!skb))
return false;
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 (!compare_ether_addr(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_tci);
if (!skb)
return false;
skb_pull(skb, offset + VLAN_HLEN);
skb_reset_mac_len(skb);
}
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);
return true;
}
/* Must be invoked with rcu_read_lock or with RTNL. */
struct net_device *__vlan_find_dev_deep(struct net_device *real_dev,
u16 vlan_id)
{
struct vlan_info *vlan_info = rcu_dereference_rtnl(real_dev->vlan_info);
if (vlan_info) {
return vlan_group_get_device(&vlan_info->grp, vlan_id);
} else {
/*
* Bonding slaves do not have grp assigned to themselves.
* Grp is assigned to bonding master instead.
*/
if (netif_is_bond_slave(real_dev))
return __vlan_find_dev_deep(real_dev->master, vlan_id);
}
return NULL;
}
EXPORT_SYMBOL(__vlan_find_dev_deep);
struct net_device *vlan_dev_real_dev(const struct net_device *dev)
{
return vlan_dev_priv(dev)->real_dev;
}
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;
skb_reset_mac_len(skb);
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, 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);
return skb;
err_free:
kfree_skb(skb);
return NULL;
}
/*
* vlan info and vid list
*/
static void vlan_group_free(struct vlan_group *grp)
{
int i;
for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++)
kfree(grp->vlan_devices_arrays[i]);
}
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;
unsigned short vid;
int refcount;
};
static struct vlan_vid_info *vlan_vid_info_get(struct vlan_info *vlan_info,
unsigned short vid)
{
struct vlan_vid_info *vid_info;
list_for_each_entry(vid_info, &vlan_info->vid_list, list) {
if (vid_info->vid == vid)
return vid_info;
}
return NULL;
}
static struct vlan_vid_info *vlan_vid_info_alloc(unsigned short vid)
{
struct vlan_vid_info *vid_info;
vid_info = kzalloc(sizeof(struct vlan_vid_info), GFP_KERNEL);
if (!vid_info)
return NULL;
vid_info->vid = vid;
return vid_info;
}
static int __vlan_vid_add(struct vlan_info *vlan_info, unsigned short 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(vid);
if (!vid_info)
return -ENOMEM;
if ((dev->features & NETIF_F_HW_VLAN_FILTER) &&
ops->ndo_vlan_rx_add_vid) {
err = ops->ndo_vlan_rx_add_vid(dev, 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, unsigned short 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, vid);
if (!vid_info) {
err = __vlan_vid_add(vlan_info, 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;
unsigned short vid = vid_info->vid;
int err;
if ((dev->features & NETIF_F_HW_VLAN_FILTER) &&
ops->ndo_vlan_rx_kill_vid) {
err = ops->ndo_vlan_rx_kill_vid(dev, vid);
if (err) {
pr_warn("failed to kill vid %d for device %s\n",
vid, dev->name);
}
}
list_del(&vid_info->list);
kfree(vid_info);
vlan_info->nr_vids--;
}
void vlan_vid_del(struct net_device *dev, unsigned short 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, 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->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->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->vid);
}
EXPORT_SYMBOL(vlan_vids_del_by_dev);