dev.c 85.8 KB
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/*
 * 	NET3	Protocol independent device support routines.
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 *	Derived from the non IP parts of dev.c 1.0.19
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 * 		Authors:	Ross Biro
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 *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *				Mark Evans, <evansmp@uhura.aston.ac.uk>
 *
 *	Additional Authors:
 *		Florian la Roche <rzsfl@rz.uni-sb.de>
 *		Alan Cox <gw4pts@gw4pts.ampr.org>
 *		David Hinds <dahinds@users.sourceforge.net>
 *		Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
 *		Adam Sulmicki <adam@cfar.umd.edu>
 *              Pekka Riikonen <priikone@poesidon.pspt.fi>
 *
 *	Changes:
 *              D.J. Barrow     :       Fixed bug where dev->refcnt gets set
 *              			to 2 if register_netdev gets called
 *              			before net_dev_init & also removed a
 *              			few lines of code in the process.
 *		Alan Cox	:	device private ioctl copies fields back.
 *		Alan Cox	:	Transmit queue code does relevant
 *					stunts to keep the queue safe.
 *		Alan Cox	:	Fixed double lock.
 *		Alan Cox	:	Fixed promisc NULL pointer trap
 *		????????	:	Support the full private ioctl range
 *		Alan Cox	:	Moved ioctl permission check into
 *					drivers
 *		Tim Kordas	:	SIOCADDMULTI/SIOCDELMULTI
 *		Alan Cox	:	100 backlog just doesn't cut it when
 *					you start doing multicast video 8)
 *		Alan Cox	:	Rewrote net_bh and list manager.
 *		Alan Cox	: 	Fix ETH_P_ALL echoback lengths.
 *		Alan Cox	:	Took out transmit every packet pass
 *					Saved a few bytes in the ioctl handler
 *		Alan Cox	:	Network driver sets packet type before
 *					calling netif_rx. Saves a function
 *					call a packet.
 *		Alan Cox	:	Hashed net_bh()
 *		Richard Kooijman:	Timestamp fixes.
 *		Alan Cox	:	Wrong field in SIOCGIFDSTADDR
 *		Alan Cox	:	Device lock protection.
 *		Alan Cox	: 	Fixed nasty side effect of device close
 *					changes.
 *		Rudi Cilibrasi	:	Pass the right thing to
 *					set_mac_address()
 *		Dave Miller	:	32bit quantity for the device lock to
 *					make it work out on a Sparc.
 *		Bjorn Ekwall	:	Added KERNELD hack.
 *		Alan Cox	:	Cleaned up the backlog initialise.
 *		Craig Metz	:	SIOCGIFCONF fix if space for under
 *					1 device.
 *	    Thomas Bogendoerfer :	Return ENODEV for dev_open, if there
 *					is no device open function.
 *		Andi Kleen	:	Fix error reporting for SIOCGIFCONF
 *	    Michael Chastain	:	Fix signed/unsigned for SIOCGIFCONF
 *		Cyrus Durgin	:	Cleaned for KMOD
 *		Adam Sulmicki   :	Bug Fix : Network Device Unload
 *					A network device unload needs to purge
 *					the backlog queue.
 *	Paul Rusty Russell	:	SIOCSIFNAME
 *              Pekka Riikonen  :	Netdev boot-time settings code
 *              Andrew Morton   :       Make unregister_netdevice wait
 *              			indefinitely on dev->refcnt
 * 		J Hadi Salim	:	- Backlog queue sampling
 *				        - netif_rx() feedback
 */

#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/bitops.h>
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#include <linux/capability.h>
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#include <linux/config.h>
#include <linux/cpu.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
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#include <linux/mutex.h>
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#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/if_ether.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/notifier.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/rtnetlink.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/stat.h>
#include <linux/if_bridge.h>
#include <linux/divert.h>
#include <net/dst.h>
#include <net/pkt_sched.h>
#include <net/checksum.h>
#include <linux/highmem.h>
#include <linux/init.h>
#include <linux/kmod.h>
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/netpoll.h>
#include <linux/rcupdate.h>
#include <linux/delay.h>
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#include <linux/wireless.h>
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#include <net/iw_handler.h>
#include <asm/current.h>
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#include <linux/audit.h>
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#include <linux/dmaengine.h>
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#include <linux/err.h>
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/*
 *	The list of packet types we will receive (as opposed to discard)
 *	and the routines to invoke.
 *
 *	Why 16. Because with 16 the only overlap we get on a hash of the
 *	low nibble of the protocol value is RARP/SNAP/X.25.
 *
 *      NOTE:  That is no longer true with the addition of VLAN tags.  Not
 *             sure which should go first, but I bet it won't make much
 *             difference if we are running VLANs.  The good news is that
 *             this protocol won't be in the list unless compiled in, so
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 *             the average user (w/out VLANs) will not be adversely affected.
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 *             --BLG
 *
 *		0800	IP
 *		8100    802.1Q VLAN
 *		0001	802.3
 *		0002	AX.25
 *		0004	802.2
 *		8035	RARP
 *		0005	SNAP
 *		0805	X.25
 *		0806	ARP
 *		8137	IPX
 *		0009	Localtalk
 *		86DD	IPv6
 */

static DEFINE_SPINLOCK(ptype_lock);
static struct list_head ptype_base[16];	/* 16 way hashed list */
static struct list_head ptype_all;		/* Taps */

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#ifdef CONFIG_NET_DMA
static struct dma_client *net_dma_client;
static unsigned int net_dma_count;
static spinlock_t net_dma_event_lock;
#endif

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/*
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 * The @dev_base list is protected by @dev_base_lock and the rtnl
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 * semaphore.
 *
 * Pure readers hold dev_base_lock for reading.
 *
 * Writers must hold the rtnl semaphore while they loop through the
 * dev_base list, and hold dev_base_lock for writing when they do the
 * actual updates.  This allows pure readers to access the list even
 * while a writer is preparing to update it.
 *
 * To put it another way, dev_base_lock is held for writing only to
 * protect against pure readers; the rtnl semaphore provides the
 * protection against other writers.
 *
 * See, for example usages, register_netdevice() and
 * unregister_netdevice(), which must be called with the rtnl
 * semaphore held.
 */
struct net_device *dev_base;
static struct net_device **dev_tail = &dev_base;
DEFINE_RWLOCK(dev_base_lock);

EXPORT_SYMBOL(dev_base);
EXPORT_SYMBOL(dev_base_lock);

#define NETDEV_HASHBITS	8
static struct hlist_head dev_name_head[1<<NETDEV_HASHBITS];
static struct hlist_head dev_index_head[1<<NETDEV_HASHBITS];

static inline struct hlist_head *dev_name_hash(const char *name)
{
	unsigned hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
	return &dev_name_head[hash & ((1<<NETDEV_HASHBITS)-1)];
}

static inline struct hlist_head *dev_index_hash(int ifindex)
{
	return &dev_index_head[ifindex & ((1<<NETDEV_HASHBITS)-1)];
}

/*
 *	Our notifier list
 */

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static RAW_NOTIFIER_HEAD(netdev_chain);
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/*
 *	Device drivers call our routines to queue packets here. We empty the
 *	queue in the local softnet handler.
 */
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DEFINE_PER_CPU(struct softnet_data, softnet_data) = { NULL };
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#ifdef CONFIG_SYSFS
extern int netdev_sysfs_init(void);
extern int netdev_register_sysfs(struct net_device *);
extern void netdev_unregister_sysfs(struct net_device *);
#else
#define netdev_sysfs_init()	 	(0)
#define netdev_register_sysfs(dev)	(0)
#define	netdev_unregister_sysfs(dev)	do { } while(0)
#endif


/*******************************************************************************

		Protocol management and registration routines

*******************************************************************************/

/*
 *	For efficiency
 */

int netdev_nit;

/*
 *	Add a protocol ID to the list. Now that the input handler is
 *	smarter we can dispense with all the messy stuff that used to be
 *	here.
 *
 *	BEWARE!!! Protocol handlers, mangling input packets,
 *	MUST BE last in hash buckets and checking protocol handlers
 *	MUST start from promiscuous ptype_all chain in net_bh.
 *	It is true now, do not change it.
 *	Explanation follows: if protocol handler, mangling packet, will
 *	be the first on list, it is not able to sense, that packet
 *	is cloned and should be copied-on-write, so that it will
 *	change it and subsequent readers will get broken packet.
 *							--ANK (980803)
 */

/**
 *	dev_add_pack - add packet handler
 *	@pt: packet type declaration
 *
 *	Add a protocol handler to the networking stack. The passed &packet_type
 *	is linked into kernel lists and may not be freed until it has been
 *	removed from the kernel lists.
 *
 *	This call does not sleep therefore it can not 
 *	guarantee all CPU's that are in middle of receiving packets
 *	will see the new packet type (until the next received packet).
 */

void dev_add_pack(struct packet_type *pt)
{
	int hash;

	spin_lock_bh(&ptype_lock);
	if (pt->type == htons(ETH_P_ALL)) {
		netdev_nit++;
		list_add_rcu(&pt->list, &ptype_all);
	} else {
		hash = ntohs(pt->type) & 15;
		list_add_rcu(&pt->list, &ptype_base[hash]);
	}
	spin_unlock_bh(&ptype_lock);
}

/**
 *	__dev_remove_pack	 - remove packet handler
 *	@pt: packet type declaration
 *
 *	Remove a protocol handler that was previously added to the kernel
 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
 *	from the kernel lists and can be freed or reused once this function
 *	returns. 
 *
 *      The packet type might still be in use by receivers
 *	and must not be freed until after all the CPU's have gone
 *	through a quiescent state.
 */
void __dev_remove_pack(struct packet_type *pt)
{
	struct list_head *head;
	struct packet_type *pt1;

	spin_lock_bh(&ptype_lock);

	if (pt->type == htons(ETH_P_ALL)) {
		netdev_nit--;
		head = &ptype_all;
	} else
		head = &ptype_base[ntohs(pt->type) & 15];

	list_for_each_entry(pt1, head, list) {
		if (pt == pt1) {
			list_del_rcu(&pt->list);
			goto out;
		}
	}

	printk(KERN_WARNING "dev_remove_pack: %p not found.\n", pt);
out:
	spin_unlock_bh(&ptype_lock);
}
/**
 *	dev_remove_pack	 - remove packet handler
 *	@pt: packet type declaration
 *
 *	Remove a protocol handler that was previously added to the kernel
 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
 *	from the kernel lists and can be freed or reused once this function
 *	returns.
 *
 *	This call sleeps to guarantee that no CPU is looking at the packet
 *	type after return.
 */
void dev_remove_pack(struct packet_type *pt)
{
	__dev_remove_pack(pt);
	
	synchronize_net();
}

/******************************************************************************

		      Device Boot-time Settings Routines

*******************************************************************************/

/* Boot time configuration table */
static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];

/**
 *	netdev_boot_setup_add	- add new setup entry
 *	@name: name of the device
 *	@map: configured settings for the device
 *
 *	Adds new setup entry to the dev_boot_setup list.  The function
 *	returns 0 on error and 1 on success.  This is a generic routine to
 *	all netdevices.
 */
static int netdev_boot_setup_add(char *name, struct ifmap *map)
{
	struct netdev_boot_setup *s;
	int i;

	s = dev_boot_setup;
	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
		if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
			memset(s[i].name, 0, sizeof(s[i].name));
			strcpy(s[i].name, name);
			memcpy(&s[i].map, map, sizeof(s[i].map));
			break;
		}
	}

	return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
}

/**
 *	netdev_boot_setup_check	- check boot time settings
 *	@dev: the netdevice
 *
 * 	Check boot time settings for the device.
 *	The found settings are set for the device to be used
 *	later in the device probing.
 *	Returns 0 if no settings found, 1 if they are.
 */
int netdev_boot_setup_check(struct net_device *dev)
{
	struct netdev_boot_setup *s = dev_boot_setup;
	int i;

	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
		if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
		    !strncmp(dev->name, s[i].name, strlen(s[i].name))) {
			dev->irq 	= s[i].map.irq;
			dev->base_addr 	= s[i].map.base_addr;
			dev->mem_start 	= s[i].map.mem_start;
			dev->mem_end 	= s[i].map.mem_end;
			return 1;
		}
	}
	return 0;
}


/**
 *	netdev_boot_base	- get address from boot time settings
 *	@prefix: prefix for network device
 *	@unit: id for network device
 *
 * 	Check boot time settings for the base address of device.
 *	The found settings are set for the device to be used
 *	later in the device probing.
 *	Returns 0 if no settings found.
 */
unsigned long netdev_boot_base(const char *prefix, int unit)
{
	const struct netdev_boot_setup *s = dev_boot_setup;
	char name[IFNAMSIZ];
	int i;

	sprintf(name, "%s%d", prefix, unit);

	/*
	 * If device already registered then return base of 1
	 * to indicate not to probe for this interface
	 */
	if (__dev_get_by_name(name))
		return 1;

	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
		if (!strcmp(name, s[i].name))
			return s[i].map.base_addr;
	return 0;
}

/*
 * Saves at boot time configured settings for any netdevice.
 */
int __init netdev_boot_setup(char *str)
{
	int ints[5];
	struct ifmap map;

	str = get_options(str, ARRAY_SIZE(ints), ints);
	if (!str || !*str)
		return 0;

	/* Save settings */
	memset(&map, 0, sizeof(map));
	if (ints[0] > 0)
		map.irq = ints[1];
	if (ints[0] > 1)
		map.base_addr = ints[2];
	if (ints[0] > 2)
		map.mem_start = ints[3];
	if (ints[0] > 3)
		map.mem_end = ints[4];

	/* Add new entry to the list */
	return netdev_boot_setup_add(str, &map);
}

__setup("netdev=", netdev_boot_setup);

/*******************************************************************************

			    Device Interface Subroutines

*******************************************************************************/

/**
 *	__dev_get_by_name	- find a device by its name
 *	@name: name to find
 *
 *	Find an interface by name. Must be called under RTNL semaphore
 *	or @dev_base_lock. If the name is found a pointer to the device
 *	is returned. If the name is not found then %NULL is returned. The
 *	reference counters are not incremented so the caller must be
 *	careful with locks.
 */

struct net_device *__dev_get_by_name(const char *name)
{
	struct hlist_node *p;

	hlist_for_each(p, dev_name_hash(name)) {
		struct net_device *dev
			= hlist_entry(p, struct net_device, name_hlist);
		if (!strncmp(dev->name, name, IFNAMSIZ))
			return dev;
	}
	return NULL;
}

/**
 *	dev_get_by_name		- find a device by its name
 *	@name: name to find
 *
 *	Find an interface by name. This can be called from any
 *	context and does its own locking. The returned handle has
 *	the usage count incremented and the caller must use dev_put() to
 *	release it when it is no longer needed. %NULL is returned if no
 *	matching device is found.
 */

struct net_device *dev_get_by_name(const char *name)
{
	struct net_device *dev;

	read_lock(&dev_base_lock);
	dev = __dev_get_by_name(name);
	if (dev)
		dev_hold(dev);
	read_unlock(&dev_base_lock);
	return dev;
}

/**
 *	__dev_get_by_index - find a device by its ifindex
 *	@ifindex: index of device
 *
 *	Search for an interface by index. Returns %NULL if the device
 *	is not found or a pointer to the device. The device has not
 *	had its reference counter increased so the caller must be careful
 *	about locking. The caller must hold either the RTNL semaphore
 *	or @dev_base_lock.
 */

struct net_device *__dev_get_by_index(int ifindex)
{
	struct hlist_node *p;

	hlist_for_each(p, dev_index_hash(ifindex)) {
		struct net_device *dev
			= hlist_entry(p, struct net_device, index_hlist);
		if (dev->ifindex == ifindex)
			return dev;
	}
	return NULL;
}


/**
 *	dev_get_by_index - find a device by its ifindex
 *	@ifindex: index of device
 *
 *	Search for an interface by index. Returns NULL if the device
 *	is not found or a pointer to the device. The device returned has
 *	had a reference added and the pointer is safe until the user calls
 *	dev_put to indicate they have finished with it.
 */

struct net_device *dev_get_by_index(int ifindex)
{
	struct net_device *dev;

	read_lock(&dev_base_lock);
	dev = __dev_get_by_index(ifindex);
	if (dev)
		dev_hold(dev);
	read_unlock(&dev_base_lock);
	return dev;
}

/**
 *	dev_getbyhwaddr - find a device by its hardware address
 *	@type: media type of device
 *	@ha: hardware address
 *
 *	Search for an interface by MAC address. Returns NULL if the device
 *	is not found or a pointer to the device. The caller must hold the
 *	rtnl semaphore. The returned device has not had its ref count increased
 *	and the caller must therefore be careful about locking
 *
 *	BUGS:
 *	If the API was consistent this would be __dev_get_by_hwaddr
 */

struct net_device *dev_getbyhwaddr(unsigned short type, char *ha)
{
	struct net_device *dev;

	ASSERT_RTNL();

	for (dev = dev_base; dev; dev = dev->next)
		if (dev->type == type &&
		    !memcmp(dev->dev_addr, ha, dev->addr_len))
			break;
	return dev;
}

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EXPORT_SYMBOL(dev_getbyhwaddr);

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struct net_device *dev_getfirstbyhwtype(unsigned short type)
{
	struct net_device *dev;

	rtnl_lock();
	for (dev = dev_base; dev; dev = dev->next) {
		if (dev->type == type) {
			dev_hold(dev);
			break;
		}
	}
	rtnl_unlock();
	return dev;
}

EXPORT_SYMBOL(dev_getfirstbyhwtype);

/**
 *	dev_get_by_flags - find any device with given flags
 *	@if_flags: IFF_* values
 *	@mask: bitmask of bits in if_flags to check
 *
 *	Search for any interface with the given flags. Returns NULL if a device
 *	is not found or a pointer to the device. The device returned has 
 *	had a reference added and the pointer is safe until the user calls
 *	dev_put to indicate they have finished with it.
 */

struct net_device * dev_get_by_flags(unsigned short if_flags, unsigned short mask)
{
	struct net_device *dev;

	read_lock(&dev_base_lock);
	for (dev = dev_base; dev != NULL; dev = dev->next) {
		if (((dev->flags ^ if_flags) & mask) == 0) {
			dev_hold(dev);
			break;
		}
	}
	read_unlock(&dev_base_lock);
	return dev;
}

/**
 *	dev_valid_name - check if name is okay for network device
 *	@name: name string
 *
 *	Network device names need to be valid file names to
 *	to allow sysfs to work
 */
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int dev_valid_name(const char *name)
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{
	return !(*name == '\0' 
		 || !strcmp(name, ".")
		 || !strcmp(name, "..")
		 || strchr(name, '/'));
}

/**
 *	dev_alloc_name - allocate a name for a device
 *	@dev: device
 *	@name: name format string
 *
 *	Passed a format string - eg "lt%d" it will try and find a suitable
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 *	id. It scans list of devices to build up a free map, then chooses
 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 *	while allocating the name and adding the device in order to avoid
 *	duplicates.
 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 *	Returns the number of the unit assigned or a negative errno code.
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 */

int dev_alloc_name(struct net_device *dev, const char *name)
{
	int i = 0;
	char buf[IFNAMSIZ];
	const char *p;
	const int max_netdevices = 8*PAGE_SIZE;
	long *inuse;
	struct net_device *d;

	p = strnchr(name, IFNAMSIZ-1, '%');
	if (p) {
		/*
		 * Verify the string as this thing may have come from
		 * the user.  There must be either one "%d" and no other "%"
		 * characters.
		 */
		if (p[1] != 'd' || strchr(p + 2, '%'))
			return -EINVAL;

		/* Use one page as a bit array of possible slots */
		inuse = (long *) get_zeroed_page(GFP_ATOMIC);
		if (!inuse)
			return -ENOMEM;

		for (d = dev_base; d; d = d->next) {
			if (!sscanf(d->name, name, &i))
				continue;
			if (i < 0 || i >= max_netdevices)
				continue;

			/*  avoid cases where sscanf is not exact inverse of printf */
			snprintf(buf, sizeof(buf), name, i);
			if (!strncmp(buf, d->name, IFNAMSIZ))
				set_bit(i, inuse);
		}

		i = find_first_zero_bit(inuse, max_netdevices);
		free_page((unsigned long) inuse);
	}

	snprintf(buf, sizeof(buf), name, i);
	if (!__dev_get_by_name(buf)) {
		strlcpy(dev->name, buf, IFNAMSIZ);
		return i;
	}

	/* It is possible to run out of possible slots
	 * when the name is long and there isn't enough space left
	 * for the digits, or if all bits are used.
	 */
	return -ENFILE;
}


/**
 *	dev_change_name - change name of a device
 *	@dev: device
 *	@newname: name (or format string) must be at least IFNAMSIZ
 *
 *	Change name of a device, can pass format strings "eth%d".
 *	for wildcarding.
 */
int dev_change_name(struct net_device *dev, char *newname)
{
	int err = 0;

	ASSERT_RTNL();

	if (dev->flags & IFF_UP)
		return -EBUSY;

	if (!dev_valid_name(newname))
		return -EINVAL;

	if (strchr(newname, '%')) {
		err = dev_alloc_name(dev, newname);
		if (err < 0)
			return err;
		strcpy(newname, dev->name);
	}
	else if (__dev_get_by_name(newname))
		return -EEXIST;
	else
		strlcpy(dev->name, newname, IFNAMSIZ);

	err = class_device_rename(&dev->class_dev, dev->name);
	if (!err) {
		hlist_del(&dev->name_hlist);
		hlist_add_head(&dev->name_hlist, dev_name_hash(dev->name));
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		raw_notifier_call_chain(&netdev_chain,
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				NETDEV_CHANGENAME, dev);
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	}

	return err;
}

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/**
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 *	netdev_features_change - device changes features
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 *	@dev: device to cause notification
 *
 *	Called to indicate a device has changed features.
 */
void netdev_features_change(struct net_device *dev)
{
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	raw_notifier_call_chain(&netdev_chain, NETDEV_FEAT_CHANGE, dev);
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}
EXPORT_SYMBOL(netdev_features_change);

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/**
 *	netdev_state_change - device changes state
 *	@dev: device to cause notification
 *
 *	Called to indicate a device has changed state. This function calls
 *	the notifier chains for netdev_chain and sends a NEWLINK message
 *	to the routing socket.
 */
void netdev_state_change(struct net_device *dev)
{
	if (dev->flags & IFF_UP) {
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		raw_notifier_call_chain(&netdev_chain,
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				NETDEV_CHANGE, dev);
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		rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
	}
}

/**
 *	dev_load 	- load a network module
 *	@name: name of interface
 *
 *	If a network interface is not present and the process has suitable
 *	privileges this function loads the module. If module loading is not
 *	available in this kernel then it becomes a nop.
 */

void dev_load(const char *name)
{
	struct net_device *dev;  

	read_lock(&dev_base_lock);
	dev = __dev_get_by_name(name);
	read_unlock(&dev_base_lock);

	if (!dev && capable(CAP_SYS_MODULE))
		request_module("%s", name);
}

static int default_rebuild_header(struct sk_buff *skb)
{
	printk(KERN_DEBUG "%s: default_rebuild_header called -- BUG!\n",
	       skb->dev ? skb->dev->name : "NULL!!!");
	kfree_skb(skb);
	return 1;
}


/**
 *	dev_open	- prepare an interface for use.
 *	@dev:	device to open
 *
 *	Takes a device from down to up state. The device's private open
 *	function is invoked and then the multicast lists are loaded. Finally
 *	the device is moved into the up state and a %NETDEV_UP message is
 *	sent to the netdev notifier chain.
 *
 *	Calling this function on an active interface is a nop. On a failure
 *	a negative errno code is returned.
 */
int dev_open(struct net_device *dev)
{
	int ret = 0;

	/*
	 *	Is it already up?
	 */

	if (dev->flags & IFF_UP)
		return 0;

	/*
	 *	Is it even present?
	 */
	if (!netif_device_present(dev))
		return -ENODEV;

	/*
	 *	Call device private open method
	 */
	set_bit(__LINK_STATE_START, &dev->state);
	if (dev->open) {
		ret = dev->open(dev);
		if (ret)
			clear_bit(__LINK_STATE_START, &dev->state);
	}

 	/*
	 *	If it went open OK then:
	 */

	if (!ret) {
		/*
		 *	Set the flags.
		 */
		dev->flags |= IFF_UP;

		/*
		 *	Initialize multicasting status
		 */
		dev_mc_upload(dev);

		/*
		 *	Wakeup transmit queue engine
		 */
		dev_activate(dev);

		/*
		 *	... and announce new interface.
		 */
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		raw_notifier_call_chain(&netdev_chain, NETDEV_UP, dev);
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	}
	return ret;
}

/**
 *	dev_close - shutdown an interface.
 *	@dev: device to shutdown
 *
 *	This function moves an active device into down state. A
 *	%NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
 *	is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
 *	chain.
 */
int dev_close(struct net_device *dev)
{
	if (!(dev->flags & IFF_UP))
		return 0;

	/*
	 *	Tell people we are going down, so that they can
	 *	prepare to death, when device is still operating.
	 */
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	raw_notifier_call_chain(&netdev_chain, NETDEV_GOING_DOWN, dev);
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	dev_deactivate(dev);

	clear_bit(__LINK_STATE_START, &dev->state);

	/* Synchronize to scheduled poll. We cannot touch poll list,
	 * it can be even on different cpu. So just clear netif_running(),
	 * and wait when poll really will happen. Actually, the best place
	 * for this is inside dev->stop() after device stopped its irq
	 * engine, but this requires more changes in devices. */

	smp_mb__after_clear_bit(); /* Commit netif_running(). */
	while (test_bit(__LINK_STATE_RX_SCHED, &dev->state)) {
		/* No hurry. */
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		msleep(1);
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	}

	/*
	 *	Call the device specific close. This cannot fail.
	 *	Only if device is UP
	 *
	 *	We allow it to be called even after a DETACH hot-plug
	 *	event.
	 */
	if (dev->stop)
		dev->stop(dev);

	/*
	 *	Device is now down.
	 */

	dev->flags &= ~IFF_UP;

	/*
	 * Tell people we are down
	 */
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	raw_notifier_call_chain(&netdev_chain, NETDEV_DOWN, dev);
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	return 0;
}


/*
 *	Device change register/unregister. These are not inline or static
 *	as we export them to the world.
 */

/**
 *	register_netdevice_notifier - register a network notifier block
 *	@nb: notifier
 *
 *	Register a notifier to be called when network device events occur.
 *	The notifier passed is linked into the kernel structures and must
 *	not be reused until it has been unregistered. A negative errno code
 *	is returned on a failure.
 *
 * 	When registered all registration and up events are replayed
 *	to the new notifier to allow device to have a race free 
 *	view of the network device list.
 */

int register_netdevice_notifier(struct notifier_block *nb)
{
	struct net_device *dev;
	int err;

	rtnl_lock();
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	err = raw_notifier_chain_register(&netdev_chain, nb);
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	if (!err) {
		for (dev = dev_base; dev; dev = dev->next) {
			nb->notifier_call(nb, NETDEV_REGISTER, dev);

			if (dev->flags & IFF_UP) 
				nb->notifier_call(nb, NETDEV_UP, dev);
		}
	}
	rtnl_unlock();
	return err;
}

/**
 *	unregister_netdevice_notifier - unregister a network notifier block
 *	@nb: notifier
 *
 *	Unregister a notifier previously registered by
 *	register_netdevice_notifier(). The notifier is unlinked into the
 *	kernel structures and may then be reused. A negative errno code
 *	is returned on a failure.
 */

int unregister_netdevice_notifier(struct notifier_block *nb)
{
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	int err;

	rtnl_lock();
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	err = raw_notifier_chain_unregister(&netdev_chain, nb);
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	rtnl_unlock();
	return err;
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}

/**
 *	call_netdevice_notifiers - call all network notifier blocks
 *      @val: value passed unmodified to notifier function
 *      @v:   pointer passed unmodified to notifier function
 *
 *	Call all network notifier blocks.  Parameters and return value
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 *	are as for raw_notifier_call_chain().
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 */

int call_netdevice_notifiers(unsigned long val, void *v)
{
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	return raw_notifier_call_chain(&netdev_chain, val, v);
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}

/* When > 0 there are consumers of rx skb time stamps */
static atomic_t netstamp_needed = ATOMIC_INIT(0);

void net_enable_timestamp(void)
{
	atomic_inc(&netstamp_needed);
}

void net_disable_timestamp(void)
{
	atomic_dec(&netstamp_needed);
}

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void __net_timestamp(struct sk_buff *skb)
{
	struct timeval tv;

	do_gettimeofday(&tv);
	skb_set_timestamp(skb, &tv);
}
EXPORT_SYMBOL(__net_timestamp);

static inline void net_timestamp(struct sk_buff *skb)
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{
	if (atomic_read(&netstamp_needed))
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		__net_timestamp(skb);
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	else {
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		skb->tstamp.off_sec = 0;
		skb->tstamp.off_usec = 0;
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	}
}

/*
 *	Support routine. Sends outgoing frames to any network
 *	taps currently in use.
 */

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static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
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{
	struct packet_type *ptype;
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	net_timestamp(skb);
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	rcu_read_lock();
	list_for_each_entry_rcu(ptype, &ptype_all, list) {
		/* Never send packets back to the socket
		 * they originated from - MvS (miquels@drinkel.ow.org)
		 */
		if ((ptype->dev == dev || !ptype->dev) &&
		    (ptype->af_packet_priv == NULL ||
		     (struct sock *)ptype->af_packet_priv != skb->sk)) {
			struct sk_buff *skb2= skb_clone(skb, GFP_ATOMIC);
			if (!skb2)
				break;

			/* skb->nh should be correctly
			   set by sender, so that the second statement is
			   just protection against buggy protocols.
			 */
			skb2->mac.raw = skb2->data;

			if (skb2->nh.raw < skb2->data ||
			    skb2->nh.raw > skb2->tail) {
				if (net_ratelimit())
					printk(KERN_CRIT "protocol %04x is "
					       "buggy, dev %s\n",
					       skb2->protocol, dev->name);
				skb2->nh.raw = skb2->data;
			}

			skb2->h.raw = skb2->nh.raw;
			skb2->pkt_type = PACKET_OUTGOING;
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			ptype->func(skb2, skb->dev, ptype, skb->dev);
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		}
	}
	rcu_read_unlock();
}

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void __netif_schedule(struct net_device *dev)
{
	if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) {
		unsigned long flags;
		struct softnet_data *sd;

		local_irq_save(flags);
		sd = &__get_cpu_var(softnet_data);
		dev->next_sched = sd->output_queue;
		sd->output_queue = dev;
		raise_softirq_irqoff(NET_TX_SOFTIRQ);
		local_irq_restore(flags);
	}
}
EXPORT_SYMBOL(__netif_schedule);

void __netif_rx_schedule(struct net_device *dev)
{
	unsigned long flags;

	local_irq_save(flags);
	dev_hold(dev);
	list_add_tail(&dev->poll_list, &__get_cpu_var(softnet_data).poll_list);
	if (dev->quota < 0)
		dev->quota += dev->weight;
	else
		dev->quota = dev->weight;
	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
	local_irq_restore(flags);
}
EXPORT_SYMBOL(__netif_rx_schedule);

void dev_kfree_skb_any(struct sk_buff *skb)
{
	if (in_irq() || irqs_disabled())
		dev_kfree_skb_irq(skb);
	else
		dev_kfree_skb(skb);
}
EXPORT_SYMBOL(dev_kfree_skb_any);


/* Hot-plugging. */
void netif_device_detach(struct net_device *dev)
{
	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
		netif_stop_queue(dev);
	}
}
EXPORT_SYMBOL(netif_device_detach);

void netif_device_attach(struct net_device *dev)
{
	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
		netif_wake_queue(dev);
 		__netdev_watchdog_up(dev);
	}
}
EXPORT_SYMBOL(netif_device_attach);


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/*
 * Invalidate hardware checksum when packet is to be mangled, and
 * complete checksum manually on outgoing path.
 */
int skb_checksum_help(struct sk_buff *skb, int inward)
{
	unsigned int csum;
	int ret = 0, offset = skb->h.raw - skb->data;

	if (inward) {
		skb->ip_summed = CHECKSUM_NONE;
		goto out;
	}

	if (skb_cloned(skb)) {
		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
		if (ret)
			goto out;
	}

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	BUG_ON(offset > (int)skb->len);
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	csum = skb_checksum(skb, offset, skb->len-offset, 0);

	offset = skb->tail - skb->h.raw;
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	BUG_ON(offset <= 0);
	BUG_ON(skb->csum + 2 > offset);
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	*(u16*)(skb->h.raw + skb->csum) = csum_fold(csum);
	skb->ip_summed = CHECKSUM_NONE;
out:	
	return ret;
}

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/**
 *	skb_gso_segment - Perform segmentation on skb.
 *	@skb: buffer to segment
 *	@sg: whether scatter-gather is supported on the target.
 *
 *	This function segments the given skb and returns a list of segments.
 */
struct sk_buff *skb_gso_segment(struct sk_buff *skb, int sg)
{
	struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
	struct packet_type *ptype;
	int type = skb->protocol;

	BUG_ON(skb_shinfo(skb)->frag_list);
	BUG_ON(skb->ip_summed != CHECKSUM_HW);

	skb->mac.raw = skb->data;
	skb->mac_len = skb->nh.raw - skb->data;
	__skb_pull(skb, skb->mac_len);

	rcu_read_lock();
	list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type) & 15], list) {
		if (ptype->type == type && !ptype->dev && ptype->gso_segment) {
			segs = ptype->gso_segment(skb, sg);
			break;
		}
	}
	rcu_read_unlock();

	return segs;
}

EXPORT_SYMBOL(skb_gso_segment);

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/* Take action when hardware reception checksum errors are detected. */
#ifdef CONFIG_BUG
void netdev_rx_csum_fault(struct net_device *dev)
{
	if (net_ratelimit()) {
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		printk(KERN_ERR "%s: hw csum failure.\n", 
			dev ? dev->name : "<unknown>");
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		dump_stack();
	}
}
EXPORT_SYMBOL(netdev_rx_csum_fault);
#endif

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#ifdef CONFIG_HIGHMEM
/* Actually, we should eliminate this check as soon as we know, that:
 * 1. IOMMU is present and allows to map all the memory.
 * 2. No high memory really exists on this machine.
 */

static inline int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
{
	int i;

	if (dev->features & NETIF_F_HIGHDMA)
		return 0;

	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
		if (PageHighMem(skb_shinfo(skb)->frags[i].page))
			return 1;

	return 0;
}
#else
#define illegal_highdma(dev, skb)	(0)
#endif

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struct dev_gso_cb {
	void (*destructor)(struct sk_buff *skb);
};

#define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)

static void dev_gso_skb_destructor(struct sk_buff *skb)
{
	struct dev_gso_cb *cb;

	do {
		struct sk_buff *nskb = skb->next;

		skb->next = nskb->next;
		nskb->next = NULL;
		kfree_skb(nskb);
	} while (skb->next);

	cb = DEV_GSO_CB(skb);
	if (cb->destructor)
		cb->destructor(skb);
}

/**
 *	dev_gso_segment - Perform emulated hardware segmentation on skb.
 *	@skb: buffer to segment
 *
 *	This function segments the given skb and stores the list of segments
 *	in skb->next.
 */
static int dev_gso_segment(struct sk_buff *skb)
{
	struct net_device *dev = skb->dev;
	struct sk_buff *segs;

	segs = skb_gso_segment(skb, dev->features & NETIF_F_SG &&
				    !illegal_highdma(dev, skb));
	if (unlikely(IS_ERR(segs)))
		return PTR_ERR(segs);

	skb->next = segs;
	DEV_GSO_CB(skb)->destructor = skb->destructor;
	skb->destructor = dev_gso_skb_destructor;

	return 0;
}

int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	if (likely(!skb->next)) {
		if (netdev_nit)
			dev_queue_xmit_nit(skb, dev);

		if (!netif_needs_gso(dev, skb))
			return dev->hard_start_xmit(skb, dev);

		if (unlikely(dev_gso_segment(skb)))
			goto out_kfree_skb;
	}

	do {
		struct sk_buff *nskb = skb->next;
		int rc;

		skb->next = nskb->next;
		nskb->next = NULL;
		rc = dev->hard_start_xmit(nskb, dev);
		if (unlikely(rc)) {
			skb->next = nskb;
			return rc;
		}
	} while (skb->next);
	
	skb->destructor = DEV_GSO_CB(skb)->destructor;

out_kfree_skb:
	kfree_skb(skb);
	return 0;
}

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#define HARD_TX_LOCK(dev, cpu) {			\
	if ((dev->features & NETIF_F_LLTX) == 0) {	\
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		netif_tx_lock(dev);			\
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	}						\
}

#define HARD_TX_UNLOCK(dev) {				\
	if ((dev->features & NETIF_F_LLTX) == 0) {	\
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		netif_tx_unlock(dev);			\
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	}						\
}

/**
 *	dev_queue_xmit - transmit a buffer
 *	@skb: buffer to transmit
 *
 *	Queue a buffer for transmission to a network device. The caller must
 *	have set the device and priority and built the buffer before calling
 *	this function. The function can be called from an interrupt.
 *
 *	A negative errno code is returned on a failure. A success does not
 *	guarantee the frame will be transmitted as it may be dropped due
 *	to congestion or traffic shaping.
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 *
 * -----------------------------------------------------------------------------------
 *      I notice this method can also return errors from the queue disciplines,
 *      including NET_XMIT_DROP, which is a positive value.  So, errors can also
 *      be positive.
 *
 *      Regardless of the return value, the skb is consumed, so it is currently
 *      difficult to retry a send to this method.  (You can bump the ref count
 *      before sending to hold a reference for retry if you are careful.)
 *
 *      When calling this method, interrupts MUST be enabled.  This is because
 *      the BH enable code must have IRQs enabled so that it will not deadlock.
 *          --BLG
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 */

int dev_queue_xmit(struct sk_buff *skb)
{
	struct net_device *dev = skb->dev;
	struct Qdisc *q;
	int rc = -ENOMEM;

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	/* GSO will handle the following emulations directly. */
	if (netif_needs_gso(dev, skb))
		goto gso;

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	if (skb_shinfo(skb)->frag_list &&
	    !(dev->features & NETIF_F_FRAGLIST) &&
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	    __skb_linearize(skb))
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		goto out_kfree_skb;

	/* Fragmented skb is linearized if device does not support SG,
	 * or if at least one of fragments is in highmem and device
	 * does not support DMA from it.
	 */
	if (skb_shinfo(skb)->nr_frags &&
	    (!(dev->features & NETIF_F_SG) || illegal_highdma(dev, skb)) &&
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	    __skb_linearize(skb))
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		goto out_kfree_skb;

	/* If packet is not checksummed and device does not support
	 * checksumming for this protocol, complete checksumming here.
	 */
	if (skb->ip_summed == CHECKSUM_HW &&
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	    (!(dev->features & NETIF_F_GEN_CSUM) &&
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	     (!(dev->features & NETIF_F_IP_CSUM) ||
	      skb->protocol != htons(ETH_P_IP))))
	      	if (skb_checksum_help(skb, 0))
	      		goto out_kfree_skb;

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	spin_lock_prefetch(&dev->queue_lock);

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	/* Disable soft irqs for various locks below. Also 
	 * stops preemption for RCU. 
	 */
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	rcu_read_lock_bh(); 
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	/* Updates of qdisc are serialized by queue_lock. 
	 * The struct Qdisc which is pointed to by qdisc is now a 
	 * rcu structure - it may be accessed without acquiring 
	 * a lock (but the structure may be stale.) The freeing of the
	 * qdisc will be deferred until it's known that there are no 
	 * more references to it.
	 * 
	 * If the qdisc has an enqueue function, we still need to 
	 * hold the queue_lock before calling it, since queue_lock
	 * also serializes access to the device queue.
	 */

	q = rcu_dereference(dev->qdisc);
#ifdef CONFIG_NET_CLS_ACT
	skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_EGRESS);
#endif
	if (q->enqueue) {
		/* Grab device queue */
		spin_lock(&dev->queue_lock);

		rc = q->enqueue(skb, q);

		qdisc_run(dev);

		spin_unlock(&dev->queue_lock);
		rc = rc == NET_XMIT_BYPASS ? NET_XMIT_SUCCESS : rc;
		goto out;
	}

	/* The device has no queue. Common case for software devices:
	   loopback, all the sorts of tunnels...

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	   Really, it is unlikely that netif_tx_lock protection is necessary
	   here.  (f.e. loopback and IP tunnels are clean ignoring statistics
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	   counters.)
	   However, it is possible, that they rely on protection
	   made by us here.

	   Check this and shot the lock. It is not prone from deadlocks.
	   Either shot noqueue qdisc, it is even simpler 8)
	 */
	if (dev->flags & IFF_UP) {
		int cpu = smp_processor_id(); /* ok because BHs are off */

		if (dev->xmit_lock_owner != cpu) {

			HARD_TX_LOCK(dev, cpu);

			if (!netif_queue_stopped(dev)) {
				rc = 0;
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				if (!dev_hard_start_xmit(skb, dev)) {
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					HARD_TX_UNLOCK(dev);
					goto out;
				}
			}
			HARD_TX_UNLOCK(dev);
			if (net_ratelimit())
				printk(KERN_CRIT "Virtual device %s asks to "
				       "queue packet!\n", dev->name);
		} else {
			/* Recursion is detected! It is possible,
			 * unfortunately */
			if (net_ratelimit())
				printk(KERN_CRIT "Dead loop on virtual device "
				       "%s, fix it urgently!\n", dev->name);
		}
	}

	rc = -ENETDOWN;
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	rcu_read_unlock_bh();
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out_kfree_skb:
	kfree_skb(skb);
	return rc;
out:
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	rcu_read_unlock_bh();
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	return rc;
}


/*=======================================================================
			Receiver routines
  =======================================================================*/

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int netdev_max_backlog = 1000;
int netdev_budget = 300;
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int weight_p = 64;            /* old backlog weight */

DEFINE_PER_CPU(struct netif_rx_stats, netdev_rx_stat) = { 0, };


/**
 *	netif_rx	-	post buffer to the network code
 *	@skb: buffer to post
 *
 *	This function receives a packet from a device driver and queues it for
 *	the upper (protocol) levels to process.  It always succeeds. The buffer
 *	may be dropped during processing for congestion control or by the
 *	protocol layers.
 *
 *	return values:
 *	NET_RX_SUCCESS	(no congestion)
 *	NET_RX_CN_LOW   (low congestion)
 *	NET_RX_CN_MOD   (moderate congestion)
 *	NET_RX_CN_HIGH  (high congestion)
 *	NET_RX_DROP     (packet was dropped)
 *
 */

int netif_rx(struct sk_buff *skb)
{
	struct softnet_data *queue;
	unsigned long flags;

	/* if netpoll wants it, pretend we never saw it */
	if (netpoll_rx(skb))
		return NET_RX_DROP;

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	if (!skb->tstamp.off_sec)
		net_timestamp(skb);
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	/*
	 * The code is rearranged so that the path is the most
	 * short when CPU is congested, but is still operating.
	 */
	local_irq_save(flags);
	queue = &__get_cpu_var(softnet_data);

	__get_cpu_var(netdev_rx_stat).total++;
	if (queue->input_pkt_queue.qlen <= netdev_max_backlog) {
		if (queue->input_pkt_queue.qlen) {
enqueue:
			dev_hold(skb->dev);
			__skb_queue_tail(&queue->input_pkt_queue, skb);
			local_irq_restore(flags);
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			return NET_RX_SUCCESS;
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		}

		netif_rx_schedule(&queue->backlog_dev);
		goto enqueue;
	}

	__get_cpu_var(netdev_rx_stat).dropped++;
	local_irq_restore(flags);

	kfree_skb(skb);
	return NET_RX_DROP;
}

int netif_rx_ni(struct sk_buff *skb)
{
	int err;

	preempt_disable();
	err = netif_rx(skb);
	if (local_softirq_pending())
		do_softirq();
	preempt_enable();

	return err;
}

EXPORT_SYMBOL(netif_rx_ni);

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static inline struct net_device *skb_bond(struct sk_buff *skb)
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{
	struct net_device *dev = skb->dev;

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	if (dev->master) {
		/*
		 * On bonding slaves other than the currently active
		 * slave, suppress duplicates except for 802.3ad
		 * ETH_P_SLOW and alb non-mcast/bcast.
		 */
		if (dev->priv_flags & IFF_SLAVE_INACTIVE) {
			if (dev->master->priv_flags & IFF_MASTER_ALB) {
				if (skb->pkt_type != PACKET_BROADCAST &&
				    skb->pkt_type != PACKET_MULTICAST)
					goto keep;
			}

			if (dev->master->priv_flags & IFF_MASTER_8023AD &&
			    skb->protocol == __constant_htons(ETH_P_SLOW))
				goto keep;
		
			kfree_skb(skb);
			return NULL;
		}
keep:
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		skb->dev = dev->master;
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	}
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	return dev;
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}

static void net_tx_action(struct softirq_action *h)
{
	struct softnet_data *sd = &__get_cpu_var(softnet_data);

	if (sd->completion_queue) {
		struct sk_buff *clist;

		local_irq_disable();
		clist = sd->completion_queue;
		sd->completion_queue = NULL;
		local_irq_enable();

		while (clist) {
			struct sk_buff *skb = clist;
			clist = clist->next;

			BUG_TRAP(!atomic_read(&skb->users));
			__kfree_skb(skb);
		}
	}

	if (sd->output_queue) {
		struct net_device *head;

		local_irq_disable();
		head = sd->output_queue;
		sd->output_queue = NULL;
		local_irq_enable();

		while (head) {
			struct net_device *dev = head;
			head = head->next_sched;

			smp_mb__before_clear_bit();
			clear_bit(__LINK_STATE_SCHED, &dev->state);

			if (spin_trylock(&dev->queue_lock)) {
				qdisc_run(dev);
				spin_unlock(&dev->queue_lock);
			} else {
				netif_schedule(dev);
			}
		}
	}
}

static __inline__ int deliver_skb(struct sk_buff *skb,
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				  struct packet_type *pt_prev,
				  struct net_device *orig_dev)
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{
	atomic_inc(&skb->users);
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	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
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}

#if defined(CONFIG_BRIDGE) || defined (CONFIG_BRIDGE_MODULE)
int (*br_handle_frame_hook)(struct net_bridge_port *p, struct sk_buff **pskb);
struct net_bridge;
struct net_bridge_fdb_entry *(*br_fdb_get_hook)(struct net_bridge *br,
						unsigned char *addr);
void (*br_fdb_put_hook)(struct net_bridge_fdb_entry *ent);

static __inline__ int handle_bridge(struct sk_buff **pskb,
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				    struct packet_type **pt_prev, int *ret,
				    struct net_device *orig_dev)
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{
	struct net_bridge_port *port;

	if ((*pskb)->pkt_type == PACKET_LOOPBACK ||
	    (port = rcu_dereference((*pskb)->dev->br_port)) == NULL)
		return 0;

	if (*pt_prev) {
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		*ret = deliver_skb(*pskb, *pt_prev, orig_dev);
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		*pt_prev = NULL;
	} 
	
	return br_handle_frame_hook(port, pskb);
}
#else
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#define handle_bridge(skb, pt_prev, ret, orig_dev)	(0)
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#endif

#ifdef CONFIG_NET_CLS_ACT
/* TODO: Maybe we should just force sch_ingress to be compiled in
 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
 * a compare and 2 stores extra right now if we dont have it on
 * but have CONFIG_NET_CLS_ACT
 * NOTE: This doesnt stop any functionality; if you dont have 
 * the ingress scheduler, you just cant add policies on ingress.
 *
 */
static int ing_filter(struct sk_buff *skb) 
{
	struct Qdisc *q;
	struct net_device *dev = skb->dev;
	int result = TC_ACT_OK;
	
	if (dev->qdisc_ingress) {
		__u32 ttl = (__u32) G_TC_RTTL(skb->tc_verd);
		if (MAX_RED_LOOP < ttl++) {
			printk("Redir loop detected Dropping packet (%s->%s)\n",
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				skb->input_dev->name, skb->dev->name);
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			return TC_ACT_SHOT;
		}

		skb->tc_verd = SET_TC_RTTL(skb->tc_verd,ttl);

		skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_INGRESS);
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		spin_lock(&dev->ingress_lock);
		if ((q = dev->qdisc_ingress) != NULL)
			result = q->enqueue(skb, q);
		spin_unlock(&dev->ingress_lock);

	}

	return result;
}
#endif

int netif_receive_skb(struct sk_buff *skb)
{
	struct packet_type *ptype, *pt_prev;
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	struct net_device *orig_dev;
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	int ret = NET_RX_DROP;
	unsigned short type;

	/* if we've gotten here through NAPI, check netpoll */
	if (skb->dev->poll && netpoll_rx(skb))
		return NET_RX_DROP;

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	if (!skb->tstamp.off_sec)
		net_timestamp(skb);
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	if (!skb->input_dev)
		skb->input_dev = skb->dev;

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	orig_dev = skb_bond(skb);
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	if (!orig_dev)
		return NET_RX_DROP;

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	__get_cpu_var(netdev_rx_stat).total++;

	skb->h.raw = skb->nh.raw = skb->data;
	skb->mac_len = skb->nh.raw - skb->mac.raw;

	pt_prev = NULL;

	rcu_read_lock();

#ifdef CONFIG_NET_CLS_ACT
	if (skb->tc_verd & TC_NCLS) {
		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
		goto ncls;
	}
#endif

	list_for_each_entry_rcu(ptype, &ptype_all, list) {
		if (!ptype->dev || ptype->dev == skb->dev) {
			if (pt_prev) 
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				ret = deliver_skb(skb, pt_prev, orig_dev);
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			pt_prev = ptype;
		}
	}

#ifdef CONFIG_NET_CLS_ACT
	if (pt_prev) {
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		ret = deliver_skb(skb, pt_prev, orig_dev);
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		pt_prev = NULL; /* noone else should process this after*/
	} else {
		skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
	}

	ret = ing_filter(skb);

	if (ret == TC_ACT_SHOT || (ret == TC_ACT_STOLEN)) {
		kfree_skb(skb);
		goto out;
	}

	skb->tc_verd = 0;
ncls:
#endif

	handle_diverter(skb);

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	if (handle_bridge(&skb, &pt_prev, &ret, orig_dev))
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		goto out;

	type = skb->protocol;
	list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type)&15], list) {
		if (ptype->type == type &&
		    (!ptype->dev || ptype->dev == skb->dev)) {
			if (pt_prev) 
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				ret = deliver_skb(skb, pt_prev, orig_dev);
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			pt_prev = ptype;
		}
	}

	if (pt_prev) {
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		ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
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	} else {
		kfree_skb(skb);
		/* Jamal, now you will not able to escape explaining
		 * me how you were going to use this. :-)
		 */
		ret = NET_RX_DROP;
	}

out:
	rcu_read_unlock();
	return ret;
}

static int process_backlog(struct net_device *backlog_dev, int *budget)
{
	int work = 0;
	int quota = min(backlog_dev->quota, *budget);
	struct softnet_data *queue = &__get_cpu_var(softnet_data);
	unsigned long start_time = jiffies;

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	backlog_dev->weight = weight_p;
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	for (;;) {
		struct sk_buff *skb;
		struct net_device *dev;

		local_irq_disable();
		skb = __skb_dequeue(&queue->input_pkt_queue);
		if (!skb)
			goto job_done;
		local_irq_enable();

		dev = skb->dev;

		netif_receive_skb(skb);

		dev_put(dev);

		work++;

		if (work >= quota || jiffies - start_time > 1)
			break;

	}

	backlog_dev->quota -= work;
	*budget -= work;
	return -1;

job_done:
	backlog_dev->quota -= work;
	*budget -= work;

	list_del(&backlog_dev->poll_list);
	smp_mb__before_clear_bit();
	netif_poll_enable(backlog_dev);

	local_irq_enable();
	return 0;
}

static void net_rx_action(struct softirq_action *h)
{
	struct softnet_data *queue = &__get_cpu_var(softnet_data);
	unsigned long start_time = jiffies;
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	int budget = netdev_budget;
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	void *have;

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	local_irq_disable();

	while (!list_empty(&queue->poll_list)) {
		struct net_device *dev;

		if (budget <= 0 || jiffies - start_time > 1)
			goto softnet_break;

		local_irq_enable();

		dev = list_entry(queue->poll_list.next,
				 struct net_device, poll_list);
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		have = netpoll_poll_lock(dev);
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		if (dev->quota <= 0 || dev->poll(dev, &budget)) {
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			netpoll_poll_unlock(have);
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			local_irq_disable();
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			list_move_tail(&dev->poll_list, &queue->poll_list);
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			if (dev->quota < 0)
				dev->quota += dev->weight;
			else
				dev->quota = dev->weight;
		} else {
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			netpoll_poll_unlock(have);
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			dev_put(dev);
			local_irq_disable();
		}
	}
out:
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#ifdef CONFIG_NET_DMA
	/*
	 * There may not be any more sk_buffs coming right now, so push
	 * any pending DMA copies to hardware
	 */
	if (net_dma_client) {
		struct dma_chan *chan;
		rcu_read_lock();
		list_for_each_entry_rcu(chan, &net_dma_client->channels, client_node)
			dma_async_memcpy_issue_pending(chan);
		rcu_read_unlock();
	}
#endif
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	local_irq_enable();
	return;

softnet_break:
	__get_cpu_var(netdev_rx_stat).time_squeeze++;
	__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 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;

	read_lock(&dev_base_lock);
	dev = __dev_get_by_index(ifr.ifr_ifindex);
	if (!dev) {
		read_unlock(&dev_base_lock);
		return -ENODEV;
	}

	strcpy(ifr.ifr_name, dev->name);
	read_unlock(&dev_base_lock);

	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(char __user *arg)
{
	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 (dev = dev_base; dev; dev = dev->next) {
		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.
 */
static __inline__ struct net_device *dev_get_idx(loff_t pos)
{
	struct net_device *dev;
	loff_t i;

	for (i = 0, dev = dev_base; dev && i < pos; ++i, dev = dev->next);

	return i == pos ? dev : NULL;
}

void *dev_seq_start(struct seq_file *seq, loff_t *pos)
{
	read_lock(&dev_base_lock);
	return *pos ? dev_get_idx(*pos - 1) : SEQ_START_TOKEN;
}

void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	++*pos;
	return v == SEQ_START_TOKEN ? dev_base : ((struct net_device *)v)->next;
}

void dev_seq_stop(struct seq_file *seq, void *v)
{
	read_unlock(&dev_base_lock);
}

static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
{
	if (dev->get_stats) {
		struct net_device_stats *stats = dev->get_stats(dev);

		seq_printf(seq, "%6s:%8lu %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);
	} else
		seq_printf(seq, "%6s: No statistics available.\n", dev->name);
}

/*
 *	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 netif_rx_stats *softnet_get_online(loff_t *pos)
{
	struct netif_rx_stats *rc = NULL;

	while (*pos < NR_CPUS)
	       	if (cpu_online(*pos)) {
			rc = &per_cpu(netdev_rx_stat, *pos);
			break;
		} else
			++*pos;
	return rc;
}

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)
{
	struct netif_rx_stats *s = v;

	seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x\n",
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		   s->total, s->dropped, s->time_squeeze, 0,
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		   0, 0, 0, 0, /* was fastroute */
		   s->cpu_collision );
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	return 0;
}

static 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(file, &dev_seq_ops);
}

static struct file_operations dev_seq_fops = {
	.owner	 = THIS_MODULE,
	.open    = dev_seq_open,
	.read    = seq_read,
	.llseek  = seq_lseek,
	.release = seq_release,
};

static 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 struct file_operations softnet_seq_fops = {
	.owner	 = THIS_MODULE,
	.open    = softnet_seq_open,
	.read    = seq_read,
	.llseek  = seq_lseek,
	.release = seq_release,
};

2204
#ifdef CONFIG_WIRELESS_EXT
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extern int wireless_proc_init(void);
#else
#define wireless_proc_init() 0
#endif

static int __init dev_proc_init(void)
{
	int rc = -ENOMEM;

	if (!proc_net_fops_create("dev", S_IRUGO, &dev_seq_fops))
		goto out;
	if (!proc_net_fops_create("softnet_stat", S_IRUGO, &softnet_seq_fops))
		goto out_dev;
	if (wireless_proc_init())
		goto out_softnet;
	rc = 0;
out:
	return rc;
out_softnet:
	proc_net_remove("softnet_stat");
out_dev:
	proc_net_remove("dev");
	goto out;
}
#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;
	
	synchronize_net();

	if (old)
		dev_put(old);

	if (master)
		slave->flags |= IFF_SLAVE;
	else
		slave->flags &= ~IFF_SLAVE;

	rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE);
	return 0;
}

/**
 *	dev_set_promiscuity	- update promiscuity count on a device
 *	@dev: device
 *	@inc: modifier
 *
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 *	Add or remove promiscuity from a device. While the count in the device
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 *	remains above zero the interface remains promiscuous. Once it hits zero
 *	the device reverts back to normal filtering operation. A negative inc
 *	value is used to drop promiscuity on the device.
 */
void dev_set_promiscuity(struct net_device *dev, int inc)
{
	unsigned short old_flags = dev->flags;

	if ((dev->promiscuity += inc) == 0)
		dev->flags &= ~IFF_PROMISC;
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	else
		dev->flags |= IFF_PROMISC;
	if (dev->flags != old_flags) {
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		dev_mc_upload(dev);
		printk(KERN_INFO "device %s %s promiscuous mode\n",
		       dev->name, (dev->flags & IFF_PROMISC) ? "entered" :
		       					       "left");
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		audit_log(current->audit_context, GFP_ATOMIC,
			AUDIT_ANOM_PROMISCUOUS,
			"dev=%s prom=%d old_prom=%d auid=%u",
			dev->name, (dev->flags & IFF_PROMISC),
			(old_flags & IFF_PROMISC),
			audit_get_loginuid(current->audit_context)); 
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	}
}

/**
 *	dev_set_allmulti	- update allmulti count on a device
 *	@dev: device
 *	@inc: modifier
 *
 *	Add or remove reception of all multicast frames to a device. While the
 *	count in the device remains above zero the interface remains listening
 *	to all interfaces. Once it hits zero the device reverts back to normal
 *	filtering operation. A negative @inc value is used to drop the counter
 *	when releasing a resource needing all multicasts.
 */

void dev_set_allmulti(struct net_device *dev, int inc)
{
	unsigned short old_flags = dev->flags;

	dev->flags |= IFF_ALLMULTI;
	if ((dev->allmulti += inc) == 0)
		dev->flags &= ~IFF_ALLMULTI;
	if (dev->flags ^ old_flags)
		dev_mc_upload(dev);
}

unsigned dev_get_flags(const struct net_device *dev)
{
	unsigned flags;

	flags = (dev->flags & ~(IFF_PROMISC |
				IFF_ALLMULTI |
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				IFF_RUNNING |
				IFF_LOWER_UP |
				IFF_DORMANT)) |
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		(dev->gflags & (IFF_PROMISC |
				IFF_ALLMULTI));

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	if (netif_running(dev)) {
		if (netif_oper_up(dev))
			flags |= IFF_RUNNING;
		if (netif_carrier_ok(dev))
			flags |= IFF_LOWER_UP;
		if (netif_dormant(dev))
			flags |= IFF_DORMANT;