Newer
Older
if (err) {
WARN_ON(&ptype->list == head);
kfree_skb(skb);
return NET_RX_SUCCESS;
}
out:
return netif_receive_skb(skb);
}
static void napi_gro_flush(struct napi_struct *napi)
{
struct sk_buff *skb, *next;
for (skb = napi->gro_list; skb; skb = next) {
next = skb->next;
skb->next = NULL;
napi_gro_complete(skb);
}
napi->gro_count = 0;
napi->gro_list = NULL;
}
enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
{
struct sk_buff **pp = NULL;
struct packet_type *ptype;
__be16 type = skb->protocol;
struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK];
if (!(skb->dev->features & NETIF_F_GRO))
goto normal;
if (skb_is_gso(skb) || skb_has_frags(skb))
rcu_read_lock();
list_for_each_entry_rcu(ptype, head, list) {
if (ptype->type != type || ptype->dev || !ptype->gro_receive)
continue;
skb_set_network_header(skb, skb_gro_offset(skb));
mac_len = skb->network_header - skb->mac_header;
skb->mac_len = mac_len;
NAPI_GRO_CB(skb)->same_flow = 0;
NAPI_GRO_CB(skb)->flush = 0;
pp = ptype->gro_receive(&napi->gro_list, skb);
break;
}
rcu_read_unlock();
if (&ptype->list == head)
goto normal;
same_flow = NAPI_GRO_CB(skb)->same_flow;
ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
if (pp) {
struct sk_buff *nskb = *pp;
*pp = nskb->next;
nskb->next = NULL;
napi_gro_complete(nskb);
napi->gro_count--;
if (NAPI_GRO_CB(skb)->flush || napi->gro_count >= MAX_GRO_SKBS)
napi->gro_count++;
NAPI_GRO_CB(skb)->count = 1;
skb_shinfo(skb)->gso_size = skb_gro_len(skb);
skb->next = napi->gro_list;
napi->gro_list = skb;
if (skb_headlen(skb) < skb_gro_offset(skb)) {
int grow = skb_gro_offset(skb) - skb_headlen(skb);
BUG_ON(skb->end - skb->tail < grow);
memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
skb->tail += grow;
skb->data_len -= grow;
skb_shinfo(skb)->frags[0].page_offset += grow;
skb_shinfo(skb)->frags[0].size -= grow;
if (unlikely(!skb_shinfo(skb)->frags[0].size)) {
put_page(skb_shinfo(skb)->frags[0].page);
memmove(skb_shinfo(skb)->frags,
skb_shinfo(skb)->frags + 1,
--skb_shinfo(skb)->nr_frags);
}
ret = GRO_NORMAL;
goto pull;
EXPORT_SYMBOL(dev_gro_receive);
static gro_result_t
__napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
if (netpoll_rx_on(skb))
return GRO_NORMAL;
for (p = napi->gro_list; p; p = p->next) {
NAPI_GRO_CB(p)->same_flow =
(p->dev == skb->dev) &&
!compare_ether_header(skb_mac_header(p),
skb_gro_mac_header(skb));
NAPI_GRO_CB(p)->flush = 0;
}
return dev_gro_receive(napi, skb);
}
gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
switch (ret) {
case GRO_NORMAL:
if (netif_receive_skb(skb))
ret = GRO_DROP;
break;
case GRO_DROP:
case GRO_MERGED_FREE:
case GRO_HELD:
case GRO_MERGED:
break;
return ret;
}
EXPORT_SYMBOL(napi_skb_finish);
void skb_gro_reset_offset(struct sk_buff *skb)
{
NAPI_GRO_CB(skb)->data_offset = 0;
NAPI_GRO_CB(skb)->frag0 = NULL;
NAPI_GRO_CB(skb)->frag0_len = 0;
if (skb->mac_header == skb->tail &&
!PageHighMem(skb_shinfo(skb)->frags[0].page)) {
NAPI_GRO_CB(skb)->frag0 =
page_address(skb_shinfo(skb)->frags[0].page) +
skb_shinfo(skb)->frags[0].page_offset;
NAPI_GRO_CB(skb)->frag0_len = skb_shinfo(skb)->frags[0].size;
}
}
EXPORT_SYMBOL(skb_gro_reset_offset);
gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
skb_gro_reset_offset(skb);
return napi_skb_finish(__napi_gro_receive(napi, skb), skb);
}
EXPORT_SYMBOL(napi_gro_receive);
void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
{
__skb_pull(skb, skb_headlen(skb));
skb_reserve(skb, NET_IP_ALIGN - skb_headroom(skb));
napi->skb = skb;
}
EXPORT_SYMBOL(napi_reuse_skb);
struct sk_buff *napi_get_frags(struct napi_struct *napi)
{
struct sk_buff *skb = napi->skb;
if (!skb) {
skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
if (skb)
napi->skb = skb;
EXPORT_SYMBOL(napi_get_frags);
gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
gro_result_t ret)
switch (ret) {
case GRO_NORMAL:
skb->protocol = eth_type_trans(skb, skb->dev);
if (ret == GRO_HELD)
skb_gro_pull(skb, -ETH_HLEN);
else if (netif_receive_skb(skb))
ret = GRO_DROP;
case GRO_DROP:
case GRO_MERGED_FREE:
napi_reuse_skb(napi, skb);
break;
case GRO_MERGED:
break;
return ret;
EXPORT_SYMBOL(napi_frags_finish);
struct sk_buff *napi_frags_skb(struct napi_struct *napi)
{
struct sk_buff *skb = napi->skb;
struct ethhdr *eth;
unsigned int hlen;
unsigned int off;
napi->skb = NULL;
skb_reset_mac_header(skb);
skb_gro_reset_offset(skb);
off = skb_gro_offset(skb);
hlen = off + sizeof(*eth);
eth = skb_gro_header_fast(skb, off);
if (skb_gro_header_hard(skb, hlen)) {
eth = skb_gro_header_slow(skb, hlen, off);
if (unlikely(!eth)) {
napi_reuse_skb(napi, skb);
skb = NULL;
goto out;
}
}
skb_gro_pull(skb, sizeof(*eth));
/*
* This works because the only protocols we care about don't require
* special handling. We'll fix it up properly at the end.
*/
skb->protocol = eth->h_proto;
out:
return skb;
}
EXPORT_SYMBOL(napi_frags_skb);
gro_result_t napi_gro_frags(struct napi_struct *napi)
struct sk_buff *skb = napi_frags_skb(napi);
return GRO_DROP;
return napi_frags_finish(napi, skb, __napi_gro_receive(napi, skb));
}
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/*
* net_rps_action sends any pending IPI's for rps.
* Note: called with local irq disabled, but exits with local irq enabled.
*/
static void net_rps_action_and_irq_enable(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
struct softnet_data *remsd = sd->rps_ipi_list;
if (remsd) {
sd->rps_ipi_list = NULL;
local_irq_enable();
/* Send pending IPI's to kick RPS processing on remote cpus. */
while (remsd) {
struct softnet_data *next = remsd->rps_ipi_next;
if (cpu_online(remsd->cpu))
__smp_call_function_single(remsd->cpu,
&remsd->csd, 0);
remsd = next;
}
} else
#endif
local_irq_enable();
}
static int process_backlog(struct napi_struct *napi, int quota)
struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
#ifdef CONFIG_RPS
/* Check if we have pending ipi, its better to send them now,
* not waiting net_rx_action() end.
*/
if (sd->rps_ipi_list) {
local_irq_disable();
net_rps_action_and_irq_enable(sd);
}
#endif
napi->weight = weight_p;
local_irq_disable();
while (work < quota) {
unsigned int qlen;
while ((skb = __skb_dequeue(&sd->process_queue))) {
local_irq_enable();
__netif_receive_skb(skb);
if (++work >= quota)
return work;
local_irq_disable();
}
qlen = skb_queue_len(&sd->input_pkt_queue);
if (qlen) {
input_queue_head_add(sd, qlen);
skb_queue_splice_tail_init(&sd->input_pkt_queue,
&sd->process_queue);
}
if (qlen < quota - work) {
/*
* Inline a custom version of __napi_complete().
* only current cpu owns and manipulates this napi,
* and NAPI_STATE_SCHED is the only possible flag set on backlog.
* we can use a plain write instead of clear_bit(),
* and we dont need an smp_mb() memory barrier.
*/
list_del(&napi->poll_list);
napi->state = 0;
quota = work + qlen;
}
}
local_irq_enable();
return work;
}
/**
* __napi_schedule - schedule for receive
* @n: entry to schedule
*
* The entry's receive function will be scheduled to run
*/
void __napi_schedule(struct napi_struct *n)
{
unsigned long flags;
local_irq_save(flags);
____napi_schedule(&__get_cpu_var(softnet_data), n);
local_irq_restore(flags);
EXPORT_SYMBOL(__napi_schedule);
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void __napi_complete(struct napi_struct *n)
{
BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
BUG_ON(n->gro_list);
list_del(&n->poll_list);
smp_mb__before_clear_bit();
clear_bit(NAPI_STATE_SCHED, &n->state);
}
EXPORT_SYMBOL(__napi_complete);
void napi_complete(struct napi_struct *n)
{
unsigned long flags;
/*
* don't let napi dequeue from the cpu poll list
* just in case its running on a different cpu
*/
if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
return;
napi_gro_flush(n);
local_irq_save(flags);
__napi_complete(n);
local_irq_restore(flags);
}
EXPORT_SYMBOL(napi_complete);
void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
int (*poll)(struct napi_struct *, int), int weight)
{
INIT_LIST_HEAD(&napi->poll_list);
napi->gro_count = 0;
napi->poll = poll;
napi->weight = weight;
list_add(&napi->dev_list, &dev->napi_list);
napi->dev = dev;
spin_lock_init(&napi->poll_lock);
napi->poll_owner = -1;
#endif
set_bit(NAPI_STATE_SCHED, &napi->state);
}
EXPORT_SYMBOL(netif_napi_add);
void netif_napi_del(struct napi_struct *napi)
{
struct sk_buff *skb, *next;
list_del_init(&napi->dev_list);
for (skb = napi->gro_list; skb; skb = next) {
next = skb->next;
skb->next = NULL;
kfree_skb(skb);
}
napi->gro_list = NULL;
napi->gro_count = 0;
}
EXPORT_SYMBOL(netif_napi_del);
static void net_rx_action(struct softirq_action *h)
{
struct softnet_data *sd = &__get_cpu_var(softnet_data);
unsigned long time_limit = jiffies + 2;
int budget = netdev_budget;
while (!list_empty(&sd->poll_list)) {
struct napi_struct *n;
int work, weight;
/* If softirq window is exhuasted then punt.
* Allow this to run for 2 jiffies since which will allow
* an average latency of 1.5/HZ.
*/
if (unlikely(budget <= 0 || time_after(jiffies, time_limit)))
goto softnet_break;
local_irq_enable();
/* Even though interrupts have been re-enabled, this
* access is safe because interrupts can only add new
* entries to the tail of this list, and only ->poll()
* calls can remove this head entry from the list.
*/
n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
have = netpoll_poll_lock(n);
weight = n->weight;
/* This NAPI_STATE_SCHED test is for avoiding a race
* with netpoll's poll_napi(). Only the entity which
* obtains the lock and sees NAPI_STATE_SCHED set will
* actually make the ->poll() call. Therefore we avoid
* accidently calling ->poll() when NAPI is not scheduled.
*/
work = 0;
if (test_bit(NAPI_STATE_SCHED, &n->state)) {
work = n->poll(n, weight);
trace_napi_poll(n);
}
WARN_ON_ONCE(work > weight);
budget -= work;
local_irq_disable();
/* Drivers must not modify the NAPI state if they
* consume the entire weight. In such cases this code
* still "owns" the NAPI instance and therefore can
* move the instance around on the list at-will.
*/
if (unlikely(work == weight)) {
if (unlikely(napi_disable_pending(n))) {
local_irq_enable();
napi_complete(n);
local_irq_disable();
} else
list_move_tail(&n->poll_list, &sd->poll_list);
netpoll_poll_unlock(have);
net_rps_action_and_irq_enable(sd);
#ifdef CONFIG_NET_DMA
/*
* There may not be any more sk_buffs coming right now, so push
* any pending DMA copies to hardware
*/
dma_issue_pending_all();
__raise_softirq_irqoff(NET_RX_SOFTIRQ);
goto out;
}
static gifconf_func_t *gifconf_list[NPROTO];
/**
* register_gifconf - register a SIOCGIF handler
* @family: Address family
* @gifconf: Function handler
*
* Register protocol dependent address dumping routines. The handler
* that is passed must not be freed or reused until it has been replaced
* by another handler.
*/
int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
{
if (family >= NPROTO)
return -EINVAL;
gifconf_list[family] = gifconf;
return 0;
}
/*
* Map an interface index to its name (SIOCGIFNAME)
*/
/*
* We need this ioctl for efficient implementation of the
* if_indextoname() function required by the IPv6 API. Without
* it, we would have to search all the interfaces to find a
* match. --pb
*/
static int dev_ifname(struct net *net, struct ifreq __user *arg)
{
struct net_device *dev;
struct ifreq ifr;
/*
* Fetch the caller's info block.
*/
if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
return -EFAULT;
rcu_read_lock();
dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex);
return -ENODEV;
}
strcpy(ifr.ifr_name, dev->name);
if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
return -EFAULT;
return 0;
}
/*
* Perform a SIOCGIFCONF call. This structure will change
* size eventually, and there is nothing I can do about it.
* Thus we will need a 'compatibility mode'.
*/
static int dev_ifconf(struct net *net, char __user *arg)
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{
struct ifconf ifc;
struct net_device *dev;
char __user *pos;
int len;
int total;
int i;
/*
* Fetch the caller's info block.
*/
if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
return -EFAULT;
pos = ifc.ifc_buf;
len = ifc.ifc_len;
/*
* Loop over the interfaces, and write an info block for each.
*/
total = 0;
for_each_netdev(net, dev) {
for (i = 0; i < NPROTO; i++) {
if (gifconf_list[i]) {
int done;
if (!pos)
done = gifconf_list[i](dev, NULL, 0);
else
done = gifconf_list[i](dev, pos + total,
len - total);
if (done < 0)
return -EFAULT;
total += done;
}
}
/*
* All done. Write the updated control block back to the caller.
*/
ifc.ifc_len = total;
/*
* Both BSD and Solaris return 0 here, so we do too.
*/
return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
}
#ifdef CONFIG_PROC_FS
/*
* This is invoked by the /proc filesystem handler to display a device
* in detail.
*/
void *dev_seq_start(struct seq_file *seq, loff_t *pos)
struct net *net = seq_file_net(seq);
if (!*pos)
return SEQ_START_TOKEN;
for_each_netdev_rcu(net, dev)
if (off++ == *pos)
return dev;
}
void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct net_device *dev = (v == SEQ_START_TOKEN) ?
first_net_device(seq_file_net(seq)) :
next_net_device((struct net_device *)v);
return rcu_dereference(dev);
}
void dev_seq_stop(struct seq_file *seq, void *v)
}
static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
{
const struct net_device_stats *stats = dev_get_stats(dev);
seq_printf(seq, "%6s: %7lu %7lu %4lu %4lu %4lu %5lu %10lu %9lu "
"%8lu %7lu %4lu %4lu %4lu %5lu %7lu %10lu\n",
dev->name, stats->rx_bytes, stats->rx_packets,
stats->rx_errors,
stats->rx_dropped + stats->rx_missed_errors,
stats->rx_fifo_errors,
stats->rx_length_errors + stats->rx_over_errors +
stats->rx_crc_errors + stats->rx_frame_errors,
stats->rx_compressed, stats->multicast,
stats->tx_bytes, stats->tx_packets,
stats->tx_errors, stats->tx_dropped,
stats->tx_fifo_errors, stats->collisions,
stats->tx_carrier_errors +
stats->tx_aborted_errors +
stats->tx_window_errors +
stats->tx_heartbeat_errors,
stats->tx_compressed);
}
/*
* Called from the PROCfs module. This now uses the new arbitrary sized
* /proc/net interface to create /proc/net/dev
*/
static int dev_seq_show(struct seq_file *seq, void *v)
{
if (v == SEQ_START_TOKEN)
seq_puts(seq, "Inter-| Receive "
" | Transmit\n"
" face |bytes packets errs drop fifo frame "
"compressed multicast|bytes packets errs "
"drop fifo colls carrier compressed\n");
else
dev_seq_printf_stats(seq, v);
return 0;
}
static struct softnet_data *softnet_get_online(loff_t *pos)
}
static void *softnet_seq_start(struct seq_file *seq, loff_t *pos)
{
return softnet_get_online(pos);
}
static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
++*pos;
return softnet_get_online(pos);
}
static void softnet_seq_stop(struct seq_file *seq, void *v)
{
}
static int softnet_seq_show(struct seq_file *seq, void *v)
{
seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x\n",
0, 0, 0, 0, /* was fastroute */
static const struct seq_operations dev_seq_ops = {
.start = dev_seq_start,
.next = dev_seq_next,
.stop = dev_seq_stop,
.show = dev_seq_show,
};
static int dev_seq_open(struct inode *inode, struct file *file)
{
return seq_open_net(inode, file, &dev_seq_ops,
sizeof(struct seq_net_private));
static const struct file_operations dev_seq_fops = {
.owner = THIS_MODULE,
.open = dev_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_net,
static const struct seq_operations softnet_seq_ops = {
.start = softnet_seq_start,
.next = softnet_seq_next,
.stop = softnet_seq_stop,
.show = softnet_seq_show,
};
static int softnet_seq_open(struct inode *inode, struct file *file)
{
return seq_open(file, &softnet_seq_ops);
}
static const struct file_operations softnet_seq_fops = {
.owner = THIS_MODULE,
.open = softnet_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static void *ptype_get_idx(loff_t pos)
{
struct packet_type *pt = NULL;
loff_t i = 0;
int t;
list_for_each_entry_rcu(pt, &ptype_all, list) {
if (i == pos)
return pt;
++i;
}
for (t = 0; t < PTYPE_HASH_SIZE; t++) {
list_for_each_entry_rcu(pt, &ptype_base[t], list) {
if (i == pos)
return pt;
++i;
}
}
return NULL;
}
static void *ptype_seq_start(struct seq_file *seq, loff_t *pos)
__acquires(RCU)
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{
rcu_read_lock();
return *pos ? ptype_get_idx(*pos - 1) : SEQ_START_TOKEN;
}
static void *ptype_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct packet_type *pt;
struct list_head *nxt;
int hash;
++*pos;
if (v == SEQ_START_TOKEN)
return ptype_get_idx(0);
pt = v;
nxt = pt->list.next;
if (pt->type == htons(ETH_P_ALL)) {
if (nxt != &ptype_all)
goto found;
hash = 0;
nxt = ptype_base[0].next;
} else
hash = ntohs(pt->type) & PTYPE_HASH_MASK;
while (nxt == &ptype_base[hash]) {
if (++hash >= PTYPE_HASH_SIZE)
return NULL;
nxt = ptype_base[hash].next;
}
found:
return list_entry(nxt, struct packet_type, list);
}
static void ptype_seq_stop(struct seq_file *seq, void *v)
__releases(RCU)
{
rcu_read_unlock();
}
static int ptype_seq_show(struct seq_file *seq, void *v)
{
struct packet_type *pt = v;
if (v == SEQ_START_TOKEN)
seq_puts(seq, "Type Device Function\n");
else if (pt->dev == NULL || dev_net(pt->dev) == seq_file_net(seq)) {
if (pt->type == htons(ETH_P_ALL))
seq_puts(seq, "ALL ");
else
seq_printf(seq, "%04x", ntohs(pt->type));
seq_printf(seq, " %-8s %pF\n",
pt->dev ? pt->dev->name : "", pt->func);
}
return 0;
}
static const struct seq_operations ptype_seq_ops = {
.start = ptype_seq_start,
.next = ptype_seq_next,
.stop = ptype_seq_stop,
.show = ptype_seq_show,
};
static int ptype_seq_open(struct inode *inode, struct file *file)
{
return seq_open_net(inode, file, &ptype_seq_ops,
sizeof(struct seq_net_private));
}
static const struct file_operations ptype_seq_fops = {
.owner = THIS_MODULE,
.open = ptype_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_net,
static int __net_init dev_proc_net_init(struct net *net)
if (!proc_net_fops_create(net, "dev", S_IRUGO, &dev_seq_fops))
if (!proc_net_fops_create(net, "softnet_stat", S_IRUGO, &softnet_seq_fops))
if (!proc_net_fops_create(net, "ptype", S_IRUGO, &ptype_seq_fops))
if (wext_proc_init(net))
proc_net_remove(net, "ptype");
proc_net_remove(net, "softnet_stat");
proc_net_remove(net, "dev");
static void __net_exit dev_proc_net_exit(struct net *net)
{
wext_proc_exit(net);
proc_net_remove(net, "ptype");
proc_net_remove(net, "softnet_stat");
proc_net_remove(net, "dev");
}
static struct pernet_operations __net_initdata dev_proc_ops = {
.init = dev_proc_net_init,
.exit = dev_proc_net_exit,
};
static int __init dev_proc_init(void)
{
return register_pernet_subsys(&dev_proc_ops);
}
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#else
#define dev_proc_init() 0
#endif /* CONFIG_PROC_FS */
/**
* netdev_set_master - set up master/slave pair
* @slave: slave device
* @master: new master device
*
* Changes the master device of the slave. Pass %NULL to break the
* bonding. The caller must hold the RTNL semaphore. On a failure
* a negative errno code is returned. On success the reference counts
* are adjusted, %RTM_NEWLINK is sent to the routing socket and the
* function returns zero.
*/
int netdev_set_master(struct net_device *slave, struct net_device *master)
{
struct net_device *old = slave->master;
ASSERT_RTNL();
if (master) {
if (old)
return -EBUSY;
dev_hold(master);
}
slave->master = master;
if (master)
slave->flags |= IFF_SLAVE;
else
slave->flags &= ~IFF_SLAVE;
rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE);
return 0;
}
static void dev_change_rx_flags(struct net_device *dev, int flags)
{