xref: /linux/net/core/dev.c (revision f24e9f586b377749dff37554696cf3a105540c94)
1 /*
2  * 	NET3	Protocol independent device support routines.
3  *
4  *		This program is free software; you can redistribute it and/or
5  *		modify it under the terms of the GNU General Public License
6  *		as published by the Free Software Foundation; either version
7  *		2 of the License, or (at your option) any later version.
8  *
9  *	Derived from the non IP parts of dev.c 1.0.19
10  * 		Authors:	Ross Biro
11  *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *				Mark Evans, <evansmp@uhura.aston.ac.uk>
13  *
14  *	Additional Authors:
15  *		Florian la Roche <rzsfl@rz.uni-sb.de>
16  *		Alan Cox <gw4pts@gw4pts.ampr.org>
17  *		David Hinds <dahinds@users.sourceforge.net>
18  *		Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
19  *		Adam Sulmicki <adam@cfar.umd.edu>
20  *              Pekka Riikonen <priikone@poesidon.pspt.fi>
21  *
22  *	Changes:
23  *              D.J. Barrow     :       Fixed bug where dev->refcnt gets set
24  *              			to 2 if register_netdev gets called
25  *              			before net_dev_init & also removed a
26  *              			few lines of code in the process.
27  *		Alan Cox	:	device private ioctl copies fields back.
28  *		Alan Cox	:	Transmit queue code does relevant
29  *					stunts to keep the queue safe.
30  *		Alan Cox	:	Fixed double lock.
31  *		Alan Cox	:	Fixed promisc NULL pointer trap
32  *		????????	:	Support the full private ioctl range
33  *		Alan Cox	:	Moved ioctl permission check into
34  *					drivers
35  *		Tim Kordas	:	SIOCADDMULTI/SIOCDELMULTI
36  *		Alan Cox	:	100 backlog just doesn't cut it when
37  *					you start doing multicast video 8)
38  *		Alan Cox	:	Rewrote net_bh and list manager.
39  *		Alan Cox	: 	Fix ETH_P_ALL echoback lengths.
40  *		Alan Cox	:	Took out transmit every packet pass
41  *					Saved a few bytes in the ioctl handler
42  *		Alan Cox	:	Network driver sets packet type before
43  *					calling netif_rx. Saves a function
44  *					call a packet.
45  *		Alan Cox	:	Hashed net_bh()
46  *		Richard Kooijman:	Timestamp fixes.
47  *		Alan Cox	:	Wrong field in SIOCGIFDSTADDR
48  *		Alan Cox	:	Device lock protection.
49  *		Alan Cox	: 	Fixed nasty side effect of device close
50  *					changes.
51  *		Rudi Cilibrasi	:	Pass the right thing to
52  *					set_mac_address()
53  *		Dave Miller	:	32bit quantity for the device lock to
54  *					make it work out on a Sparc.
55  *		Bjorn Ekwall	:	Added KERNELD hack.
56  *		Alan Cox	:	Cleaned up the backlog initialise.
57  *		Craig Metz	:	SIOCGIFCONF fix if space for under
58  *					1 device.
59  *	    Thomas Bogendoerfer :	Return ENODEV for dev_open, if there
60  *					is no device open function.
61  *		Andi Kleen	:	Fix error reporting for SIOCGIFCONF
62  *	    Michael Chastain	:	Fix signed/unsigned for SIOCGIFCONF
63  *		Cyrus Durgin	:	Cleaned for KMOD
64  *		Adam Sulmicki   :	Bug Fix : Network Device Unload
65  *					A network device unload needs to purge
66  *					the backlog queue.
67  *	Paul Rusty Russell	:	SIOCSIFNAME
68  *              Pekka Riikonen  :	Netdev boot-time settings code
69  *              Andrew Morton   :       Make unregister_netdevice wait
70  *              			indefinitely on dev->refcnt
71  * 		J Hadi Salim	:	- Backlog queue sampling
72  *				        - netif_rx() feedback
73  */
74 
75 #include <asm/uaccess.h>
76 #include <asm/system.h>
77 #include <linux/bitops.h>
78 #include <linux/capability.h>
79 #include <linux/cpu.h>
80 #include <linux/types.h>
81 #include <linux/kernel.h>
82 #include <linux/sched.h>
83 #include <linux/mutex.h>
84 #include <linux/string.h>
85 #include <linux/mm.h>
86 #include <linux/socket.h>
87 #include <linux/sockios.h>
88 #include <linux/errno.h>
89 #include <linux/interrupt.h>
90 #include <linux/if_ether.h>
91 #include <linux/netdevice.h>
92 #include <linux/etherdevice.h>
93 #include <linux/notifier.h>
94 #include <linux/skbuff.h>
95 #include <net/sock.h>
96 #include <linux/rtnetlink.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/stat.h>
100 #include <linux/if_bridge.h>
101 #include <linux/divert.h>
102 #include <net/dst.h>
103 #include <net/pkt_sched.h>
104 #include <net/checksum.h>
105 #include <linux/highmem.h>
106 #include <linux/init.h>
107 #include <linux/kmod.h>
108 #include <linux/module.h>
109 #include <linux/kallsyms.h>
110 #include <linux/netpoll.h>
111 #include <linux/rcupdate.h>
112 #include <linux/delay.h>
113 #include <linux/wireless.h>
114 #include <net/iw_handler.h>
115 #include <asm/current.h>
116 #include <linux/audit.h>
117 #include <linux/dmaengine.h>
118 #include <linux/err.h>
119 #include <linux/ctype.h>
120 
121 /*
122  *	The list of packet types we will receive (as opposed to discard)
123  *	and the routines to invoke.
124  *
125  *	Why 16. Because with 16 the only overlap we get on a hash of the
126  *	low nibble of the protocol value is RARP/SNAP/X.25.
127  *
128  *      NOTE:  That is no longer true with the addition of VLAN tags.  Not
129  *             sure which should go first, but I bet it won't make much
130  *             difference if we are running VLANs.  The good news is that
131  *             this protocol won't be in the list unless compiled in, so
132  *             the average user (w/out VLANs) will not be adversely affected.
133  *             --BLG
134  *
135  *		0800	IP
136  *		8100    802.1Q VLAN
137  *		0001	802.3
138  *		0002	AX.25
139  *		0004	802.2
140  *		8035	RARP
141  *		0005	SNAP
142  *		0805	X.25
143  *		0806	ARP
144  *		8137	IPX
145  *		0009	Localtalk
146  *		86DD	IPv6
147  */
148 
149 static DEFINE_SPINLOCK(ptype_lock);
150 static struct list_head ptype_base[16];	/* 16 way hashed list */
151 static struct list_head ptype_all;		/* Taps */
152 
153 #ifdef CONFIG_NET_DMA
154 static struct dma_client *net_dma_client;
155 static unsigned int net_dma_count;
156 static spinlock_t net_dma_event_lock;
157 #endif
158 
159 /*
160  * The @dev_base list is protected by @dev_base_lock and the rtnl
161  * semaphore.
162  *
163  * Pure readers hold dev_base_lock for reading.
164  *
165  * Writers must hold the rtnl semaphore while they loop through the
166  * dev_base list, and hold dev_base_lock for writing when they do the
167  * actual updates.  This allows pure readers to access the list even
168  * while a writer is preparing to update it.
169  *
170  * To put it another way, dev_base_lock is held for writing only to
171  * protect against pure readers; the rtnl semaphore provides the
172  * protection against other writers.
173  *
174  * See, for example usages, register_netdevice() and
175  * unregister_netdevice(), which must be called with the rtnl
176  * semaphore held.
177  */
178 struct net_device *dev_base;
179 static struct net_device **dev_tail = &dev_base;
180 DEFINE_RWLOCK(dev_base_lock);
181 
182 EXPORT_SYMBOL(dev_base);
183 EXPORT_SYMBOL(dev_base_lock);
184 
185 #define NETDEV_HASHBITS	8
186 static struct hlist_head dev_name_head[1<<NETDEV_HASHBITS];
187 static struct hlist_head dev_index_head[1<<NETDEV_HASHBITS];
188 
189 static inline struct hlist_head *dev_name_hash(const char *name)
190 {
191 	unsigned hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
192 	return &dev_name_head[hash & ((1<<NETDEV_HASHBITS)-1)];
193 }
194 
195 static inline struct hlist_head *dev_index_hash(int ifindex)
196 {
197 	return &dev_index_head[ifindex & ((1<<NETDEV_HASHBITS)-1)];
198 }
199 
200 /*
201  *	Our notifier list
202  */
203 
204 static RAW_NOTIFIER_HEAD(netdev_chain);
205 
206 /*
207  *	Device drivers call our routines to queue packets here. We empty the
208  *	queue in the local softnet handler.
209  */
210 DEFINE_PER_CPU(struct softnet_data, softnet_data) = { NULL };
211 
212 #ifdef CONFIG_SYSFS
213 extern int netdev_sysfs_init(void);
214 extern int netdev_register_sysfs(struct net_device *);
215 extern void netdev_unregister_sysfs(struct net_device *);
216 #else
217 #define netdev_sysfs_init()	 	(0)
218 #define netdev_register_sysfs(dev)	(0)
219 #define	netdev_unregister_sysfs(dev)	do { } while(0)
220 #endif
221 
222 
223 /*******************************************************************************
224 
225 		Protocol management and registration routines
226 
227 *******************************************************************************/
228 
229 /*
230  *	For efficiency
231  */
232 
233 static int netdev_nit;
234 
235 /*
236  *	Add a protocol ID to the list. Now that the input handler is
237  *	smarter we can dispense with all the messy stuff that used to be
238  *	here.
239  *
240  *	BEWARE!!! Protocol handlers, mangling input packets,
241  *	MUST BE last in hash buckets and checking protocol handlers
242  *	MUST start from promiscuous ptype_all chain in net_bh.
243  *	It is true now, do not change it.
244  *	Explanation follows: if protocol handler, mangling packet, will
245  *	be the first on list, it is not able to sense, that packet
246  *	is cloned and should be copied-on-write, so that it will
247  *	change it and subsequent readers will get broken packet.
248  *							--ANK (980803)
249  */
250 
251 /**
252  *	dev_add_pack - add packet handler
253  *	@pt: packet type declaration
254  *
255  *	Add a protocol handler to the networking stack. The passed &packet_type
256  *	is linked into kernel lists and may not be freed until it has been
257  *	removed from the kernel lists.
258  *
259  *	This call does not sleep therefore it can not
260  *	guarantee all CPU's that are in middle of receiving packets
261  *	will see the new packet type (until the next received packet).
262  */
263 
264 void dev_add_pack(struct packet_type *pt)
265 {
266 	int hash;
267 
268 	spin_lock_bh(&ptype_lock);
269 	if (pt->type == htons(ETH_P_ALL)) {
270 		netdev_nit++;
271 		list_add_rcu(&pt->list, &ptype_all);
272 	} else {
273 		hash = ntohs(pt->type) & 15;
274 		list_add_rcu(&pt->list, &ptype_base[hash]);
275 	}
276 	spin_unlock_bh(&ptype_lock);
277 }
278 
279 /**
280  *	__dev_remove_pack	 - remove packet handler
281  *	@pt: packet type declaration
282  *
283  *	Remove a protocol handler that was previously added to the kernel
284  *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
285  *	from the kernel lists and can be freed or reused once this function
286  *	returns.
287  *
288  *      The packet type might still be in use by receivers
289  *	and must not be freed until after all the CPU's have gone
290  *	through a quiescent state.
291  */
292 void __dev_remove_pack(struct packet_type *pt)
293 {
294 	struct list_head *head;
295 	struct packet_type *pt1;
296 
297 	spin_lock_bh(&ptype_lock);
298 
299 	if (pt->type == htons(ETH_P_ALL)) {
300 		netdev_nit--;
301 		head = &ptype_all;
302 	} else
303 		head = &ptype_base[ntohs(pt->type) & 15];
304 
305 	list_for_each_entry(pt1, head, list) {
306 		if (pt == pt1) {
307 			list_del_rcu(&pt->list);
308 			goto out;
309 		}
310 	}
311 
312 	printk(KERN_WARNING "dev_remove_pack: %p not found.\n", pt);
313 out:
314 	spin_unlock_bh(&ptype_lock);
315 }
316 /**
317  *	dev_remove_pack	 - remove packet handler
318  *	@pt: packet type declaration
319  *
320  *	Remove a protocol handler that was previously added to the kernel
321  *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
322  *	from the kernel lists and can be freed or reused once this function
323  *	returns.
324  *
325  *	This call sleeps to guarantee that no CPU is looking at the packet
326  *	type after return.
327  */
328 void dev_remove_pack(struct packet_type *pt)
329 {
330 	__dev_remove_pack(pt);
331 
332 	synchronize_net();
333 }
334 
335 /******************************************************************************
336 
337 		      Device Boot-time Settings Routines
338 
339 *******************************************************************************/
340 
341 /* Boot time configuration table */
342 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
343 
344 /**
345  *	netdev_boot_setup_add	- add new setup entry
346  *	@name: name of the device
347  *	@map: configured settings for the device
348  *
349  *	Adds new setup entry to the dev_boot_setup list.  The function
350  *	returns 0 on error and 1 on success.  This is a generic routine to
351  *	all netdevices.
352  */
353 static int netdev_boot_setup_add(char *name, struct ifmap *map)
354 {
355 	struct netdev_boot_setup *s;
356 	int i;
357 
358 	s = dev_boot_setup;
359 	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
360 		if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
361 			memset(s[i].name, 0, sizeof(s[i].name));
362 			strcpy(s[i].name, name);
363 			memcpy(&s[i].map, map, sizeof(s[i].map));
364 			break;
365 		}
366 	}
367 
368 	return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
369 }
370 
371 /**
372  *	netdev_boot_setup_check	- check boot time settings
373  *	@dev: the netdevice
374  *
375  * 	Check boot time settings for the device.
376  *	The found settings are set for the device to be used
377  *	later in the device probing.
378  *	Returns 0 if no settings found, 1 if they are.
379  */
380 int netdev_boot_setup_check(struct net_device *dev)
381 {
382 	struct netdev_boot_setup *s = dev_boot_setup;
383 	int i;
384 
385 	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
386 		if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
387 		    !strncmp(dev->name, s[i].name, strlen(s[i].name))) {
388 			dev->irq 	= s[i].map.irq;
389 			dev->base_addr 	= s[i].map.base_addr;
390 			dev->mem_start 	= s[i].map.mem_start;
391 			dev->mem_end 	= s[i].map.mem_end;
392 			return 1;
393 		}
394 	}
395 	return 0;
396 }
397 
398 
399 /**
400  *	netdev_boot_base	- get address from boot time settings
401  *	@prefix: prefix for network device
402  *	@unit: id for network device
403  *
404  * 	Check boot time settings for the base address of device.
405  *	The found settings are set for the device to be used
406  *	later in the device probing.
407  *	Returns 0 if no settings found.
408  */
409 unsigned long netdev_boot_base(const char *prefix, int unit)
410 {
411 	const struct netdev_boot_setup *s = dev_boot_setup;
412 	char name[IFNAMSIZ];
413 	int i;
414 
415 	sprintf(name, "%s%d", prefix, unit);
416 
417 	/*
418 	 * If device already registered then return base of 1
419 	 * to indicate not to probe for this interface
420 	 */
421 	if (__dev_get_by_name(name))
422 		return 1;
423 
424 	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
425 		if (!strcmp(name, s[i].name))
426 			return s[i].map.base_addr;
427 	return 0;
428 }
429 
430 /*
431  * Saves at boot time configured settings for any netdevice.
432  */
433 int __init netdev_boot_setup(char *str)
434 {
435 	int ints[5];
436 	struct ifmap map;
437 
438 	str = get_options(str, ARRAY_SIZE(ints), ints);
439 	if (!str || !*str)
440 		return 0;
441 
442 	/* Save settings */
443 	memset(&map, 0, sizeof(map));
444 	if (ints[0] > 0)
445 		map.irq = ints[1];
446 	if (ints[0] > 1)
447 		map.base_addr = ints[2];
448 	if (ints[0] > 2)
449 		map.mem_start = ints[3];
450 	if (ints[0] > 3)
451 		map.mem_end = ints[4];
452 
453 	/* Add new entry to the list */
454 	return netdev_boot_setup_add(str, &map);
455 }
456 
457 __setup("netdev=", netdev_boot_setup);
458 
459 /*******************************************************************************
460 
461 			    Device Interface Subroutines
462 
463 *******************************************************************************/
464 
465 /**
466  *	__dev_get_by_name	- find a device by its name
467  *	@name: name to find
468  *
469  *	Find an interface by name. Must be called under RTNL semaphore
470  *	or @dev_base_lock. If the name is found a pointer to the device
471  *	is returned. If the name is not found then %NULL is returned. The
472  *	reference counters are not incremented so the caller must be
473  *	careful with locks.
474  */
475 
476 struct net_device *__dev_get_by_name(const char *name)
477 {
478 	struct hlist_node *p;
479 
480 	hlist_for_each(p, dev_name_hash(name)) {
481 		struct net_device *dev
482 			= hlist_entry(p, struct net_device, name_hlist);
483 		if (!strncmp(dev->name, name, IFNAMSIZ))
484 			return dev;
485 	}
486 	return NULL;
487 }
488 
489 /**
490  *	dev_get_by_name		- find a device by its name
491  *	@name: name to find
492  *
493  *	Find an interface by name. This can be called from any
494  *	context and does its own locking. The returned handle has
495  *	the usage count incremented and the caller must use dev_put() to
496  *	release it when it is no longer needed. %NULL is returned if no
497  *	matching device is found.
498  */
499 
500 struct net_device *dev_get_by_name(const char *name)
501 {
502 	struct net_device *dev;
503 
504 	read_lock(&dev_base_lock);
505 	dev = __dev_get_by_name(name);
506 	if (dev)
507 		dev_hold(dev);
508 	read_unlock(&dev_base_lock);
509 	return dev;
510 }
511 
512 /**
513  *	__dev_get_by_index - find a device by its ifindex
514  *	@ifindex: index of device
515  *
516  *	Search for an interface by index. Returns %NULL if the device
517  *	is not found or a pointer to the device. The device has not
518  *	had its reference counter increased so the caller must be careful
519  *	about locking. The caller must hold either the RTNL semaphore
520  *	or @dev_base_lock.
521  */
522 
523 struct net_device *__dev_get_by_index(int ifindex)
524 {
525 	struct hlist_node *p;
526 
527 	hlist_for_each(p, dev_index_hash(ifindex)) {
528 		struct net_device *dev
529 			= hlist_entry(p, struct net_device, index_hlist);
530 		if (dev->ifindex == ifindex)
531 			return dev;
532 	}
533 	return NULL;
534 }
535 
536 
537 /**
538  *	dev_get_by_index - find a device by its ifindex
539  *	@ifindex: index of device
540  *
541  *	Search for an interface by index. Returns NULL if the device
542  *	is not found or a pointer to the device. The device returned has
543  *	had a reference added and the pointer is safe until the user calls
544  *	dev_put to indicate they have finished with it.
545  */
546 
547 struct net_device *dev_get_by_index(int ifindex)
548 {
549 	struct net_device *dev;
550 
551 	read_lock(&dev_base_lock);
552 	dev = __dev_get_by_index(ifindex);
553 	if (dev)
554 		dev_hold(dev);
555 	read_unlock(&dev_base_lock);
556 	return dev;
557 }
558 
559 /**
560  *	dev_getbyhwaddr - find a device by its hardware address
561  *	@type: media type of device
562  *	@ha: hardware address
563  *
564  *	Search for an interface by MAC address. Returns NULL if the device
565  *	is not found or a pointer to the device. The caller must hold the
566  *	rtnl semaphore. The returned device has not had its ref count increased
567  *	and the caller must therefore be careful about locking
568  *
569  *	BUGS:
570  *	If the API was consistent this would be __dev_get_by_hwaddr
571  */
572 
573 struct net_device *dev_getbyhwaddr(unsigned short type, char *ha)
574 {
575 	struct net_device *dev;
576 
577 	ASSERT_RTNL();
578 
579 	for (dev = dev_base; dev; dev = dev->next)
580 		if (dev->type == type &&
581 		    !memcmp(dev->dev_addr, ha, dev->addr_len))
582 			break;
583 	return dev;
584 }
585 
586 EXPORT_SYMBOL(dev_getbyhwaddr);
587 
588 struct net_device *dev_getfirstbyhwtype(unsigned short type)
589 {
590 	struct net_device *dev;
591 
592 	rtnl_lock();
593 	for (dev = dev_base; dev; dev = dev->next) {
594 		if (dev->type == type) {
595 			dev_hold(dev);
596 			break;
597 		}
598 	}
599 	rtnl_unlock();
600 	return dev;
601 }
602 
603 EXPORT_SYMBOL(dev_getfirstbyhwtype);
604 
605 /**
606  *	dev_get_by_flags - find any device with given flags
607  *	@if_flags: IFF_* values
608  *	@mask: bitmask of bits in if_flags to check
609  *
610  *	Search for any interface with the given flags. Returns NULL if a device
611  *	is not found or a pointer to the device. The device returned has
612  *	had a reference added and the pointer is safe until the user calls
613  *	dev_put to indicate they have finished with it.
614  */
615 
616 struct net_device * dev_get_by_flags(unsigned short if_flags, unsigned short mask)
617 {
618 	struct net_device *dev;
619 
620 	read_lock(&dev_base_lock);
621 	for (dev = dev_base; dev != NULL; dev = dev->next) {
622 		if (((dev->flags ^ if_flags) & mask) == 0) {
623 			dev_hold(dev);
624 			break;
625 		}
626 	}
627 	read_unlock(&dev_base_lock);
628 	return dev;
629 }
630 
631 /**
632  *	dev_valid_name - check if name is okay for network device
633  *	@name: name string
634  *
635  *	Network device names need to be valid file names to
636  *	to allow sysfs to work.  We also disallow any kind of
637  *	whitespace.
638  */
639 int dev_valid_name(const char *name)
640 {
641 	if (*name == '\0')
642 		return 0;
643 	if (!strcmp(name, ".") || !strcmp(name, ".."))
644 		return 0;
645 
646 	while (*name) {
647 		if (*name == '/' || isspace(*name))
648 			return 0;
649 		name++;
650 	}
651 	return 1;
652 }
653 
654 /**
655  *	dev_alloc_name - allocate a name for a device
656  *	@dev: device
657  *	@name: name format string
658  *
659  *	Passed a format string - eg "lt%d" it will try and find a suitable
660  *	id. It scans list of devices to build up a free map, then chooses
661  *	the first empty slot. The caller must hold the dev_base or rtnl lock
662  *	while allocating the name and adding the device in order to avoid
663  *	duplicates.
664  *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
665  *	Returns the number of the unit assigned or a negative errno code.
666  */
667 
668 int dev_alloc_name(struct net_device *dev, const char *name)
669 {
670 	int i = 0;
671 	char buf[IFNAMSIZ];
672 	const char *p;
673 	const int max_netdevices = 8*PAGE_SIZE;
674 	long *inuse;
675 	struct net_device *d;
676 
677 	p = strnchr(name, IFNAMSIZ-1, '%');
678 	if (p) {
679 		/*
680 		 * Verify the string as this thing may have come from
681 		 * the user.  There must be either one "%d" and no other "%"
682 		 * characters.
683 		 */
684 		if (p[1] != 'd' || strchr(p + 2, '%'))
685 			return -EINVAL;
686 
687 		/* Use one page as a bit array of possible slots */
688 		inuse = (long *) get_zeroed_page(GFP_ATOMIC);
689 		if (!inuse)
690 			return -ENOMEM;
691 
692 		for (d = dev_base; d; d = d->next) {
693 			if (!sscanf(d->name, name, &i))
694 				continue;
695 			if (i < 0 || i >= max_netdevices)
696 				continue;
697 
698 			/*  avoid cases where sscanf is not exact inverse of printf */
699 			snprintf(buf, sizeof(buf), name, i);
700 			if (!strncmp(buf, d->name, IFNAMSIZ))
701 				set_bit(i, inuse);
702 		}
703 
704 		i = find_first_zero_bit(inuse, max_netdevices);
705 		free_page((unsigned long) inuse);
706 	}
707 
708 	snprintf(buf, sizeof(buf), name, i);
709 	if (!__dev_get_by_name(buf)) {
710 		strlcpy(dev->name, buf, IFNAMSIZ);
711 		return i;
712 	}
713 
714 	/* It is possible to run out of possible slots
715 	 * when the name is long and there isn't enough space left
716 	 * for the digits, or if all bits are used.
717 	 */
718 	return -ENFILE;
719 }
720 
721 
722 /**
723  *	dev_change_name - change name of a device
724  *	@dev: device
725  *	@newname: name (or format string) must be at least IFNAMSIZ
726  *
727  *	Change name of a device, can pass format strings "eth%d".
728  *	for wildcarding.
729  */
730 int dev_change_name(struct net_device *dev, char *newname)
731 {
732 	int err = 0;
733 
734 	ASSERT_RTNL();
735 
736 	if (dev->flags & IFF_UP)
737 		return -EBUSY;
738 
739 	if (!dev_valid_name(newname))
740 		return -EINVAL;
741 
742 	if (strchr(newname, '%')) {
743 		err = dev_alloc_name(dev, newname);
744 		if (err < 0)
745 			return err;
746 		strcpy(newname, dev->name);
747 	}
748 	else if (__dev_get_by_name(newname))
749 		return -EEXIST;
750 	else
751 		strlcpy(dev->name, newname, IFNAMSIZ);
752 
753 	err = class_device_rename(&dev->class_dev, dev->name);
754 	if (!err) {
755 		hlist_del(&dev->name_hlist);
756 		hlist_add_head(&dev->name_hlist, dev_name_hash(dev->name));
757 		raw_notifier_call_chain(&netdev_chain,
758 				NETDEV_CHANGENAME, dev);
759 	}
760 
761 	return err;
762 }
763 
764 /**
765  *	netdev_features_change - device changes features
766  *	@dev: device to cause notification
767  *
768  *	Called to indicate a device has changed features.
769  */
770 void netdev_features_change(struct net_device *dev)
771 {
772 	raw_notifier_call_chain(&netdev_chain, NETDEV_FEAT_CHANGE, dev);
773 }
774 EXPORT_SYMBOL(netdev_features_change);
775 
776 /**
777  *	netdev_state_change - device changes state
778  *	@dev: device to cause notification
779  *
780  *	Called to indicate a device has changed state. This function calls
781  *	the notifier chains for netdev_chain and sends a NEWLINK message
782  *	to the routing socket.
783  */
784 void netdev_state_change(struct net_device *dev)
785 {
786 	if (dev->flags & IFF_UP) {
787 		raw_notifier_call_chain(&netdev_chain,
788 				NETDEV_CHANGE, dev);
789 		rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
790 	}
791 }
792 
793 /**
794  *	dev_load 	- load a network module
795  *	@name: name of interface
796  *
797  *	If a network interface is not present and the process has suitable
798  *	privileges this function loads the module. If module loading is not
799  *	available in this kernel then it becomes a nop.
800  */
801 
802 void dev_load(const char *name)
803 {
804 	struct net_device *dev;
805 
806 	read_lock(&dev_base_lock);
807 	dev = __dev_get_by_name(name);
808 	read_unlock(&dev_base_lock);
809 
810 	if (!dev && capable(CAP_SYS_MODULE))
811 		request_module("%s", name);
812 }
813 
814 static int default_rebuild_header(struct sk_buff *skb)
815 {
816 	printk(KERN_DEBUG "%s: default_rebuild_header called -- BUG!\n",
817 	       skb->dev ? skb->dev->name : "NULL!!!");
818 	kfree_skb(skb);
819 	return 1;
820 }
821 
822 
823 /**
824  *	dev_open	- prepare an interface for use.
825  *	@dev:	device to open
826  *
827  *	Takes a device from down to up state. The device's private open
828  *	function is invoked and then the multicast lists are loaded. Finally
829  *	the device is moved into the up state and a %NETDEV_UP message is
830  *	sent to the netdev notifier chain.
831  *
832  *	Calling this function on an active interface is a nop. On a failure
833  *	a negative errno code is returned.
834  */
835 int dev_open(struct net_device *dev)
836 {
837 	int ret = 0;
838 
839 	/*
840 	 *	Is it already up?
841 	 */
842 
843 	if (dev->flags & IFF_UP)
844 		return 0;
845 
846 	/*
847 	 *	Is it even present?
848 	 */
849 	if (!netif_device_present(dev))
850 		return -ENODEV;
851 
852 	/*
853 	 *	Call device private open method
854 	 */
855 	set_bit(__LINK_STATE_START, &dev->state);
856 	if (dev->open) {
857 		ret = dev->open(dev);
858 		if (ret)
859 			clear_bit(__LINK_STATE_START, &dev->state);
860 	}
861 
862  	/*
863 	 *	If it went open OK then:
864 	 */
865 
866 	if (!ret) {
867 		/*
868 		 *	Set the flags.
869 		 */
870 		dev->flags |= IFF_UP;
871 
872 		/*
873 		 *	Initialize multicasting status
874 		 */
875 		dev_mc_upload(dev);
876 
877 		/*
878 		 *	Wakeup transmit queue engine
879 		 */
880 		dev_activate(dev);
881 
882 		/*
883 		 *	... and announce new interface.
884 		 */
885 		raw_notifier_call_chain(&netdev_chain, NETDEV_UP, dev);
886 	}
887 	return ret;
888 }
889 
890 /**
891  *	dev_close - shutdown an interface.
892  *	@dev: device to shutdown
893  *
894  *	This function moves an active device into down state. A
895  *	%NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
896  *	is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
897  *	chain.
898  */
899 int dev_close(struct net_device *dev)
900 {
901 	if (!(dev->flags & IFF_UP))
902 		return 0;
903 
904 	/*
905 	 *	Tell people we are going down, so that they can
906 	 *	prepare to death, when device is still operating.
907 	 */
908 	raw_notifier_call_chain(&netdev_chain, NETDEV_GOING_DOWN, dev);
909 
910 	dev_deactivate(dev);
911 
912 	clear_bit(__LINK_STATE_START, &dev->state);
913 
914 	/* Synchronize to scheduled poll. We cannot touch poll list,
915 	 * it can be even on different cpu. So just clear netif_running(),
916 	 * and wait when poll really will happen. Actually, the best place
917 	 * for this is inside dev->stop() after device stopped its irq
918 	 * engine, but this requires more changes in devices. */
919 
920 	smp_mb__after_clear_bit(); /* Commit netif_running(). */
921 	while (test_bit(__LINK_STATE_RX_SCHED, &dev->state)) {
922 		/* No hurry. */
923 		msleep(1);
924 	}
925 
926 	/*
927 	 *	Call the device specific close. This cannot fail.
928 	 *	Only if device is UP
929 	 *
930 	 *	We allow it to be called even after a DETACH hot-plug
931 	 *	event.
932 	 */
933 	if (dev->stop)
934 		dev->stop(dev);
935 
936 	/*
937 	 *	Device is now down.
938 	 */
939 
940 	dev->flags &= ~IFF_UP;
941 
942 	/*
943 	 * Tell people we are down
944 	 */
945 	raw_notifier_call_chain(&netdev_chain, NETDEV_DOWN, dev);
946 
947 	return 0;
948 }
949 
950 
951 /*
952  *	Device change register/unregister. These are not inline or static
953  *	as we export them to the world.
954  */
955 
956 /**
957  *	register_netdevice_notifier - register a network notifier block
958  *	@nb: notifier
959  *
960  *	Register a notifier to be called when network device events occur.
961  *	The notifier passed is linked into the kernel structures and must
962  *	not be reused until it has been unregistered. A negative errno code
963  *	is returned on a failure.
964  *
965  * 	When registered all registration and up events are replayed
966  *	to the new notifier to allow device to have a race free
967  *	view of the network device list.
968  */
969 
970 int register_netdevice_notifier(struct notifier_block *nb)
971 {
972 	struct net_device *dev;
973 	int err;
974 
975 	rtnl_lock();
976 	err = raw_notifier_chain_register(&netdev_chain, nb);
977 	if (!err) {
978 		for (dev = dev_base; dev; dev = dev->next) {
979 			nb->notifier_call(nb, NETDEV_REGISTER, dev);
980 
981 			if (dev->flags & IFF_UP)
982 				nb->notifier_call(nb, NETDEV_UP, dev);
983 		}
984 	}
985 	rtnl_unlock();
986 	return err;
987 }
988 
989 /**
990  *	unregister_netdevice_notifier - unregister a network notifier block
991  *	@nb: notifier
992  *
993  *	Unregister a notifier previously registered by
994  *	register_netdevice_notifier(). The notifier is unlinked into the
995  *	kernel structures and may then be reused. A negative errno code
996  *	is returned on a failure.
997  */
998 
999 int unregister_netdevice_notifier(struct notifier_block *nb)
1000 {
1001 	int err;
1002 
1003 	rtnl_lock();
1004 	err = raw_notifier_chain_unregister(&netdev_chain, nb);
1005 	rtnl_unlock();
1006 	return err;
1007 }
1008 
1009 /**
1010  *	call_netdevice_notifiers - call all network notifier blocks
1011  *      @val: value passed unmodified to notifier function
1012  *      @v:   pointer passed unmodified to notifier function
1013  *
1014  *	Call all network notifier blocks.  Parameters and return value
1015  *	are as for raw_notifier_call_chain().
1016  */
1017 
1018 int call_netdevice_notifiers(unsigned long val, void *v)
1019 {
1020 	return raw_notifier_call_chain(&netdev_chain, val, v);
1021 }
1022 
1023 /* When > 0 there are consumers of rx skb time stamps */
1024 static atomic_t netstamp_needed = ATOMIC_INIT(0);
1025 
1026 void net_enable_timestamp(void)
1027 {
1028 	atomic_inc(&netstamp_needed);
1029 }
1030 
1031 void net_disable_timestamp(void)
1032 {
1033 	atomic_dec(&netstamp_needed);
1034 }
1035 
1036 void __net_timestamp(struct sk_buff *skb)
1037 {
1038 	struct timeval tv;
1039 
1040 	do_gettimeofday(&tv);
1041 	skb_set_timestamp(skb, &tv);
1042 }
1043 EXPORT_SYMBOL(__net_timestamp);
1044 
1045 static inline void net_timestamp(struct sk_buff *skb)
1046 {
1047 	if (atomic_read(&netstamp_needed))
1048 		__net_timestamp(skb);
1049 	else {
1050 		skb->tstamp.off_sec = 0;
1051 		skb->tstamp.off_usec = 0;
1052 	}
1053 }
1054 
1055 /*
1056  *	Support routine. Sends outgoing frames to any network
1057  *	taps currently in use.
1058  */
1059 
1060 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1061 {
1062 	struct packet_type *ptype;
1063 
1064 	net_timestamp(skb);
1065 
1066 	rcu_read_lock();
1067 	list_for_each_entry_rcu(ptype, &ptype_all, list) {
1068 		/* Never send packets back to the socket
1069 		 * they originated from - MvS (miquels@drinkel.ow.org)
1070 		 */
1071 		if ((ptype->dev == dev || !ptype->dev) &&
1072 		    (ptype->af_packet_priv == NULL ||
1073 		     (struct sock *)ptype->af_packet_priv != skb->sk)) {
1074 			struct sk_buff *skb2= skb_clone(skb, GFP_ATOMIC);
1075 			if (!skb2)
1076 				break;
1077 
1078 			/* skb->nh should be correctly
1079 			   set by sender, so that the second statement is
1080 			   just protection against buggy protocols.
1081 			 */
1082 			skb2->mac.raw = skb2->data;
1083 
1084 			if (skb2->nh.raw < skb2->data ||
1085 			    skb2->nh.raw > skb2->tail) {
1086 				if (net_ratelimit())
1087 					printk(KERN_CRIT "protocol %04x is "
1088 					       "buggy, dev %s\n",
1089 					       skb2->protocol, dev->name);
1090 				skb2->nh.raw = skb2->data;
1091 			}
1092 
1093 			skb2->h.raw = skb2->nh.raw;
1094 			skb2->pkt_type = PACKET_OUTGOING;
1095 			ptype->func(skb2, skb->dev, ptype, skb->dev);
1096 		}
1097 	}
1098 	rcu_read_unlock();
1099 }
1100 
1101 
1102 void __netif_schedule(struct net_device *dev)
1103 {
1104 	if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) {
1105 		unsigned long flags;
1106 		struct softnet_data *sd;
1107 
1108 		local_irq_save(flags);
1109 		sd = &__get_cpu_var(softnet_data);
1110 		dev->next_sched = sd->output_queue;
1111 		sd->output_queue = dev;
1112 		raise_softirq_irqoff(NET_TX_SOFTIRQ);
1113 		local_irq_restore(flags);
1114 	}
1115 }
1116 EXPORT_SYMBOL(__netif_schedule);
1117 
1118 void __netif_rx_schedule(struct net_device *dev)
1119 {
1120 	unsigned long flags;
1121 
1122 	local_irq_save(flags);
1123 	dev_hold(dev);
1124 	list_add_tail(&dev->poll_list, &__get_cpu_var(softnet_data).poll_list);
1125 	if (dev->quota < 0)
1126 		dev->quota += dev->weight;
1127 	else
1128 		dev->quota = dev->weight;
1129 	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
1130 	local_irq_restore(flags);
1131 }
1132 EXPORT_SYMBOL(__netif_rx_schedule);
1133 
1134 void dev_kfree_skb_any(struct sk_buff *skb)
1135 {
1136 	if (in_irq() || irqs_disabled())
1137 		dev_kfree_skb_irq(skb);
1138 	else
1139 		dev_kfree_skb(skb);
1140 }
1141 EXPORT_SYMBOL(dev_kfree_skb_any);
1142 
1143 
1144 /* Hot-plugging. */
1145 void netif_device_detach(struct net_device *dev)
1146 {
1147 	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
1148 	    netif_running(dev)) {
1149 		netif_stop_queue(dev);
1150 	}
1151 }
1152 EXPORT_SYMBOL(netif_device_detach);
1153 
1154 void netif_device_attach(struct net_device *dev)
1155 {
1156 	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
1157 	    netif_running(dev)) {
1158 		netif_wake_queue(dev);
1159  		__netdev_watchdog_up(dev);
1160 	}
1161 }
1162 EXPORT_SYMBOL(netif_device_attach);
1163 
1164 
1165 /*
1166  * Invalidate hardware checksum when packet is to be mangled, and
1167  * complete checksum manually on outgoing path.
1168  */
1169 int skb_checksum_help(struct sk_buff *skb, int inward)
1170 {
1171 	unsigned int csum;
1172 	int ret = 0, offset = skb->h.raw - skb->data;
1173 
1174 	if (inward)
1175 		goto out_set_summed;
1176 
1177 	if (unlikely(skb_shinfo(skb)->gso_size)) {
1178 		/* Let GSO fix up the checksum. */
1179 		goto out_set_summed;
1180 	}
1181 
1182 	if (skb_cloned(skb)) {
1183 		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
1184 		if (ret)
1185 			goto out;
1186 	}
1187 
1188 	BUG_ON(offset > (int)skb->len);
1189 	csum = skb_checksum(skb, offset, skb->len-offset, 0);
1190 
1191 	offset = skb->tail - skb->h.raw;
1192 	BUG_ON(offset <= 0);
1193 	BUG_ON(skb->csum + 2 > offset);
1194 
1195 	*(u16*)(skb->h.raw + skb->csum) = csum_fold(csum);
1196 
1197 out_set_summed:
1198 	skb->ip_summed = CHECKSUM_NONE;
1199 out:
1200 	return ret;
1201 }
1202 
1203 /**
1204  *	skb_gso_segment - Perform segmentation on skb.
1205  *	@skb: buffer to segment
1206  *	@features: features for the output path (see dev->features)
1207  *
1208  *	This function segments the given skb and returns a list of segments.
1209  *
1210  *	It may return NULL if the skb requires no segmentation.  This is
1211  *	only possible when GSO is used for verifying header integrity.
1212  */
1213 struct sk_buff *skb_gso_segment(struct sk_buff *skb, int features)
1214 {
1215 	struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
1216 	struct packet_type *ptype;
1217 	int type = skb->protocol;
1218 	int err;
1219 
1220 	BUG_ON(skb_shinfo(skb)->frag_list);
1221 
1222 	skb->mac.raw = skb->data;
1223 	skb->mac_len = skb->nh.raw - skb->data;
1224 	__skb_pull(skb, skb->mac_len);
1225 
1226 	if (unlikely(skb->ip_summed != CHECKSUM_HW)) {
1227 		if (skb_header_cloned(skb) &&
1228 		    (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
1229 			return ERR_PTR(err);
1230 	}
1231 
1232 	rcu_read_lock();
1233 	list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type) & 15], list) {
1234 		if (ptype->type == type && !ptype->dev && ptype->gso_segment) {
1235 			if (unlikely(skb->ip_summed != CHECKSUM_HW)) {
1236 				err = ptype->gso_send_check(skb);
1237 				segs = ERR_PTR(err);
1238 				if (err || skb_gso_ok(skb, features))
1239 					break;
1240 				__skb_push(skb, skb->data - skb->nh.raw);
1241 			}
1242 			segs = ptype->gso_segment(skb, features);
1243 			break;
1244 		}
1245 	}
1246 	rcu_read_unlock();
1247 
1248 	__skb_push(skb, skb->data - skb->mac.raw);
1249 
1250 	return segs;
1251 }
1252 
1253 EXPORT_SYMBOL(skb_gso_segment);
1254 
1255 /* Take action when hardware reception checksum errors are detected. */
1256 #ifdef CONFIG_BUG
1257 void netdev_rx_csum_fault(struct net_device *dev)
1258 {
1259 	if (net_ratelimit()) {
1260 		printk(KERN_ERR "%s: hw csum failure.\n",
1261 			dev ? dev->name : "<unknown>");
1262 		dump_stack();
1263 	}
1264 }
1265 EXPORT_SYMBOL(netdev_rx_csum_fault);
1266 #endif
1267 
1268 /* Actually, we should eliminate this check as soon as we know, that:
1269  * 1. IOMMU is present and allows to map all the memory.
1270  * 2. No high memory really exists on this machine.
1271  */
1272 
1273 static inline int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
1274 {
1275 #ifdef CONFIG_HIGHMEM
1276 	int i;
1277 
1278 	if (dev->features & NETIF_F_HIGHDMA)
1279 		return 0;
1280 
1281 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
1282 		if (PageHighMem(skb_shinfo(skb)->frags[i].page))
1283 			return 1;
1284 
1285 #endif
1286 	return 0;
1287 }
1288 
1289 struct dev_gso_cb {
1290 	void (*destructor)(struct sk_buff *skb);
1291 };
1292 
1293 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
1294 
1295 static void dev_gso_skb_destructor(struct sk_buff *skb)
1296 {
1297 	struct dev_gso_cb *cb;
1298 
1299 	do {
1300 		struct sk_buff *nskb = skb->next;
1301 
1302 		skb->next = nskb->next;
1303 		nskb->next = NULL;
1304 		kfree_skb(nskb);
1305 	} while (skb->next);
1306 
1307 	cb = DEV_GSO_CB(skb);
1308 	if (cb->destructor)
1309 		cb->destructor(skb);
1310 }
1311 
1312 /**
1313  *	dev_gso_segment - Perform emulated hardware segmentation on skb.
1314  *	@skb: buffer to segment
1315  *
1316  *	This function segments the given skb and stores the list of segments
1317  *	in skb->next.
1318  */
1319 static int dev_gso_segment(struct sk_buff *skb)
1320 {
1321 	struct net_device *dev = skb->dev;
1322 	struct sk_buff *segs;
1323 	int features = dev->features & ~(illegal_highdma(dev, skb) ?
1324 					 NETIF_F_SG : 0);
1325 
1326 	segs = skb_gso_segment(skb, features);
1327 
1328 	/* Verifying header integrity only. */
1329 	if (!segs)
1330 		return 0;
1331 
1332 	if (unlikely(IS_ERR(segs)))
1333 		return PTR_ERR(segs);
1334 
1335 	skb->next = segs;
1336 	DEV_GSO_CB(skb)->destructor = skb->destructor;
1337 	skb->destructor = dev_gso_skb_destructor;
1338 
1339 	return 0;
1340 }
1341 
1342 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
1343 {
1344 	if (likely(!skb->next)) {
1345 		if (netdev_nit)
1346 			dev_queue_xmit_nit(skb, dev);
1347 
1348 		if (netif_needs_gso(dev, skb)) {
1349 			if (unlikely(dev_gso_segment(skb)))
1350 				goto out_kfree_skb;
1351 			if (skb->next)
1352 				goto gso;
1353 		}
1354 
1355 		return dev->hard_start_xmit(skb, dev);
1356 	}
1357 
1358 gso:
1359 	do {
1360 		struct sk_buff *nskb = skb->next;
1361 		int rc;
1362 
1363 		skb->next = nskb->next;
1364 		nskb->next = NULL;
1365 		rc = dev->hard_start_xmit(nskb, dev);
1366 		if (unlikely(rc)) {
1367 			nskb->next = skb->next;
1368 			skb->next = nskb;
1369 			return rc;
1370 		}
1371 		if (unlikely(netif_queue_stopped(dev) && skb->next))
1372 			return NETDEV_TX_BUSY;
1373 	} while (skb->next);
1374 
1375 	skb->destructor = DEV_GSO_CB(skb)->destructor;
1376 
1377 out_kfree_skb:
1378 	kfree_skb(skb);
1379 	return 0;
1380 }
1381 
1382 #define HARD_TX_LOCK(dev, cpu) {			\
1383 	if ((dev->features & NETIF_F_LLTX) == 0) {	\
1384 		netif_tx_lock(dev);			\
1385 	}						\
1386 }
1387 
1388 #define HARD_TX_UNLOCK(dev) {				\
1389 	if ((dev->features & NETIF_F_LLTX) == 0) {	\
1390 		netif_tx_unlock(dev);			\
1391 	}						\
1392 }
1393 
1394 /**
1395  *	dev_queue_xmit - transmit a buffer
1396  *	@skb: buffer to transmit
1397  *
1398  *	Queue a buffer for transmission to a network device. The caller must
1399  *	have set the device and priority and built the buffer before calling
1400  *	this function. The function can be called from an interrupt.
1401  *
1402  *	A negative errno code is returned on a failure. A success does not
1403  *	guarantee the frame will be transmitted as it may be dropped due
1404  *	to congestion or traffic shaping.
1405  *
1406  * -----------------------------------------------------------------------------------
1407  *      I notice this method can also return errors from the queue disciplines,
1408  *      including NET_XMIT_DROP, which is a positive value.  So, errors can also
1409  *      be positive.
1410  *
1411  *      Regardless of the return value, the skb is consumed, so it is currently
1412  *      difficult to retry a send to this method.  (You can bump the ref count
1413  *      before sending to hold a reference for retry if you are careful.)
1414  *
1415  *      When calling this method, interrupts MUST be enabled.  This is because
1416  *      the BH enable code must have IRQs enabled so that it will not deadlock.
1417  *          --BLG
1418  */
1419 
1420 int dev_queue_xmit(struct sk_buff *skb)
1421 {
1422 	struct net_device *dev = skb->dev;
1423 	struct Qdisc *q;
1424 	int rc = -ENOMEM;
1425 
1426 	/* GSO will handle the following emulations directly. */
1427 	if (netif_needs_gso(dev, skb))
1428 		goto gso;
1429 
1430 	if (skb_shinfo(skb)->frag_list &&
1431 	    !(dev->features & NETIF_F_FRAGLIST) &&
1432 	    __skb_linearize(skb))
1433 		goto out_kfree_skb;
1434 
1435 	/* Fragmented skb is linearized if device does not support SG,
1436 	 * or if at least one of fragments is in highmem and device
1437 	 * does not support DMA from it.
1438 	 */
1439 	if (skb_shinfo(skb)->nr_frags &&
1440 	    (!(dev->features & NETIF_F_SG) || illegal_highdma(dev, skb)) &&
1441 	    __skb_linearize(skb))
1442 		goto out_kfree_skb;
1443 
1444 	/* If packet is not checksummed and device does not support
1445 	 * checksumming for this protocol, complete checksumming here.
1446 	 */
1447 	if (skb->ip_summed == CHECKSUM_HW &&
1448 	    (!(dev->features & NETIF_F_GEN_CSUM) &&
1449 	     (!(dev->features & NETIF_F_IP_CSUM) ||
1450 	      skb->protocol != htons(ETH_P_IP))))
1451 	      	if (skb_checksum_help(skb, 0))
1452 	      		goto out_kfree_skb;
1453 
1454 gso:
1455 	spin_lock_prefetch(&dev->queue_lock);
1456 
1457 	/* Disable soft irqs for various locks below. Also
1458 	 * stops preemption for RCU.
1459 	 */
1460 	rcu_read_lock_bh();
1461 
1462 	/* Updates of qdisc are serialized by queue_lock.
1463 	 * The struct Qdisc which is pointed to by qdisc is now a
1464 	 * rcu structure - it may be accessed without acquiring
1465 	 * a lock (but the structure may be stale.) The freeing of the
1466 	 * qdisc will be deferred until it's known that there are no
1467 	 * more references to it.
1468 	 *
1469 	 * If the qdisc has an enqueue function, we still need to
1470 	 * hold the queue_lock before calling it, since queue_lock
1471 	 * also serializes access to the device queue.
1472 	 */
1473 
1474 	q = rcu_dereference(dev->qdisc);
1475 #ifdef CONFIG_NET_CLS_ACT
1476 	skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_EGRESS);
1477 #endif
1478 	if (q->enqueue) {
1479 		/* Grab device queue */
1480 		spin_lock(&dev->queue_lock);
1481 
1482 		rc = q->enqueue(skb, q);
1483 
1484 		qdisc_run(dev);
1485 
1486 		spin_unlock(&dev->queue_lock);
1487 		rc = rc == NET_XMIT_BYPASS ? NET_XMIT_SUCCESS : rc;
1488 		goto out;
1489 	}
1490 
1491 	/* The device has no queue. Common case for software devices:
1492 	   loopback, all the sorts of tunnels...
1493 
1494 	   Really, it is unlikely that netif_tx_lock protection is necessary
1495 	   here.  (f.e. loopback and IP tunnels are clean ignoring statistics
1496 	   counters.)
1497 	   However, it is possible, that they rely on protection
1498 	   made by us here.
1499 
1500 	   Check this and shot the lock. It is not prone from deadlocks.
1501 	   Either shot noqueue qdisc, it is even simpler 8)
1502 	 */
1503 	if (dev->flags & IFF_UP) {
1504 		int cpu = smp_processor_id(); /* ok because BHs are off */
1505 
1506 		if (dev->xmit_lock_owner != cpu) {
1507 
1508 			HARD_TX_LOCK(dev, cpu);
1509 
1510 			if (!netif_queue_stopped(dev)) {
1511 				rc = 0;
1512 				if (!dev_hard_start_xmit(skb, dev)) {
1513 					HARD_TX_UNLOCK(dev);
1514 					goto out;
1515 				}
1516 			}
1517 			HARD_TX_UNLOCK(dev);
1518 			if (net_ratelimit())
1519 				printk(KERN_CRIT "Virtual device %s asks to "
1520 				       "queue packet!\n", dev->name);
1521 		} else {
1522 			/* Recursion is detected! It is possible,
1523 			 * unfortunately */
1524 			if (net_ratelimit())
1525 				printk(KERN_CRIT "Dead loop on virtual device "
1526 				       "%s, fix it urgently!\n", dev->name);
1527 		}
1528 	}
1529 
1530 	rc = -ENETDOWN;
1531 	rcu_read_unlock_bh();
1532 
1533 out_kfree_skb:
1534 	kfree_skb(skb);
1535 	return rc;
1536 out:
1537 	rcu_read_unlock_bh();
1538 	return rc;
1539 }
1540 
1541 
1542 /*=======================================================================
1543 			Receiver routines
1544   =======================================================================*/
1545 
1546 int netdev_max_backlog = 1000;
1547 int netdev_budget = 300;
1548 int weight_p = 64;            /* old backlog weight */
1549 
1550 DEFINE_PER_CPU(struct netif_rx_stats, netdev_rx_stat) = { 0, };
1551 
1552 
1553 /**
1554  *	netif_rx	-	post buffer to the network code
1555  *	@skb: buffer to post
1556  *
1557  *	This function receives a packet from a device driver and queues it for
1558  *	the upper (protocol) levels to process.  It always succeeds. The buffer
1559  *	may be dropped during processing for congestion control or by the
1560  *	protocol layers.
1561  *
1562  *	return values:
1563  *	NET_RX_SUCCESS	(no congestion)
1564  *	NET_RX_CN_LOW   (low congestion)
1565  *	NET_RX_CN_MOD   (moderate congestion)
1566  *	NET_RX_CN_HIGH  (high congestion)
1567  *	NET_RX_DROP     (packet was dropped)
1568  *
1569  */
1570 
1571 int netif_rx(struct sk_buff *skb)
1572 {
1573 	struct softnet_data *queue;
1574 	unsigned long flags;
1575 
1576 	/* if netpoll wants it, pretend we never saw it */
1577 	if (netpoll_rx(skb))
1578 		return NET_RX_DROP;
1579 
1580 	if (!skb->tstamp.off_sec)
1581 		net_timestamp(skb);
1582 
1583 	/*
1584 	 * The code is rearranged so that the path is the most
1585 	 * short when CPU is congested, but is still operating.
1586 	 */
1587 	local_irq_save(flags);
1588 	queue = &__get_cpu_var(softnet_data);
1589 
1590 	__get_cpu_var(netdev_rx_stat).total++;
1591 	if (queue->input_pkt_queue.qlen <= netdev_max_backlog) {
1592 		if (queue->input_pkt_queue.qlen) {
1593 enqueue:
1594 			dev_hold(skb->dev);
1595 			__skb_queue_tail(&queue->input_pkt_queue, skb);
1596 			local_irq_restore(flags);
1597 			return NET_RX_SUCCESS;
1598 		}
1599 
1600 		netif_rx_schedule(&queue->backlog_dev);
1601 		goto enqueue;
1602 	}
1603 
1604 	__get_cpu_var(netdev_rx_stat).dropped++;
1605 	local_irq_restore(flags);
1606 
1607 	kfree_skb(skb);
1608 	return NET_RX_DROP;
1609 }
1610 
1611 int netif_rx_ni(struct sk_buff *skb)
1612 {
1613 	int err;
1614 
1615 	preempt_disable();
1616 	err = netif_rx(skb);
1617 	if (local_softirq_pending())
1618 		do_softirq();
1619 	preempt_enable();
1620 
1621 	return err;
1622 }
1623 
1624 EXPORT_SYMBOL(netif_rx_ni);
1625 
1626 static inline struct net_device *skb_bond(struct sk_buff *skb)
1627 {
1628 	struct net_device *dev = skb->dev;
1629 
1630 	if (dev->master) {
1631 		if (skb_bond_should_drop(skb)) {
1632 			kfree_skb(skb);
1633 			return NULL;
1634 		}
1635 		skb->dev = dev->master;
1636 	}
1637 
1638 	return dev;
1639 }
1640 
1641 static void net_tx_action(struct softirq_action *h)
1642 {
1643 	struct softnet_data *sd = &__get_cpu_var(softnet_data);
1644 
1645 	if (sd->completion_queue) {
1646 		struct sk_buff *clist;
1647 
1648 		local_irq_disable();
1649 		clist = sd->completion_queue;
1650 		sd->completion_queue = NULL;
1651 		local_irq_enable();
1652 
1653 		while (clist) {
1654 			struct sk_buff *skb = clist;
1655 			clist = clist->next;
1656 
1657 			BUG_TRAP(!atomic_read(&skb->users));
1658 			__kfree_skb(skb);
1659 		}
1660 	}
1661 
1662 	if (sd->output_queue) {
1663 		struct net_device *head;
1664 
1665 		local_irq_disable();
1666 		head = sd->output_queue;
1667 		sd->output_queue = NULL;
1668 		local_irq_enable();
1669 
1670 		while (head) {
1671 			struct net_device *dev = head;
1672 			head = head->next_sched;
1673 
1674 			smp_mb__before_clear_bit();
1675 			clear_bit(__LINK_STATE_SCHED, &dev->state);
1676 
1677 			if (spin_trylock(&dev->queue_lock)) {
1678 				qdisc_run(dev);
1679 				spin_unlock(&dev->queue_lock);
1680 			} else {
1681 				netif_schedule(dev);
1682 			}
1683 		}
1684 	}
1685 }
1686 
1687 static __inline__ int deliver_skb(struct sk_buff *skb,
1688 				  struct packet_type *pt_prev,
1689 				  struct net_device *orig_dev)
1690 {
1691 	atomic_inc(&skb->users);
1692 	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1693 }
1694 
1695 #if defined(CONFIG_BRIDGE) || defined (CONFIG_BRIDGE_MODULE)
1696 int (*br_handle_frame_hook)(struct net_bridge_port *p, struct sk_buff **pskb);
1697 struct net_bridge;
1698 struct net_bridge_fdb_entry *(*br_fdb_get_hook)(struct net_bridge *br,
1699 						unsigned char *addr);
1700 void (*br_fdb_put_hook)(struct net_bridge_fdb_entry *ent);
1701 
1702 static __inline__ int handle_bridge(struct sk_buff **pskb,
1703 				    struct packet_type **pt_prev, int *ret,
1704 				    struct net_device *orig_dev)
1705 {
1706 	struct net_bridge_port *port;
1707 
1708 	if ((*pskb)->pkt_type == PACKET_LOOPBACK ||
1709 	    (port = rcu_dereference((*pskb)->dev->br_port)) == NULL)
1710 		return 0;
1711 
1712 	if (*pt_prev) {
1713 		*ret = deliver_skb(*pskb, *pt_prev, orig_dev);
1714 		*pt_prev = NULL;
1715 	}
1716 
1717 	return br_handle_frame_hook(port, pskb);
1718 }
1719 #else
1720 #define handle_bridge(skb, pt_prev, ret, orig_dev)	(0)
1721 #endif
1722 
1723 #ifdef CONFIG_NET_CLS_ACT
1724 /* TODO: Maybe we should just force sch_ingress to be compiled in
1725  * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
1726  * a compare and 2 stores extra right now if we dont have it on
1727  * but have CONFIG_NET_CLS_ACT
1728  * NOTE: This doesnt stop any functionality; if you dont have
1729  * the ingress scheduler, you just cant add policies on ingress.
1730  *
1731  */
1732 static int ing_filter(struct sk_buff *skb)
1733 {
1734 	struct Qdisc *q;
1735 	struct net_device *dev = skb->dev;
1736 	int result = TC_ACT_OK;
1737 
1738 	if (dev->qdisc_ingress) {
1739 		__u32 ttl = (__u32) G_TC_RTTL(skb->tc_verd);
1740 		if (MAX_RED_LOOP < ttl++) {
1741 			printk(KERN_WARNING "Redir loop detected Dropping packet (%s->%s)\n",
1742 				skb->input_dev->name, skb->dev->name);
1743 			return TC_ACT_SHOT;
1744 		}
1745 
1746 		skb->tc_verd = SET_TC_RTTL(skb->tc_verd,ttl);
1747 
1748 		skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_INGRESS);
1749 
1750 		spin_lock(&dev->ingress_lock);
1751 		if ((q = dev->qdisc_ingress) != NULL)
1752 			result = q->enqueue(skb, q);
1753 		spin_unlock(&dev->ingress_lock);
1754 
1755 	}
1756 
1757 	return result;
1758 }
1759 #endif
1760 
1761 int netif_receive_skb(struct sk_buff *skb)
1762 {
1763 	struct packet_type *ptype, *pt_prev;
1764 	struct net_device *orig_dev;
1765 	int ret = NET_RX_DROP;
1766 	unsigned short type;
1767 
1768 	/* if we've gotten here through NAPI, check netpoll */
1769 	if (skb->dev->poll && netpoll_rx(skb))
1770 		return NET_RX_DROP;
1771 
1772 	if (!skb->tstamp.off_sec)
1773 		net_timestamp(skb);
1774 
1775 	if (!skb->input_dev)
1776 		skb->input_dev = skb->dev;
1777 
1778 	orig_dev = skb_bond(skb);
1779 
1780 	if (!orig_dev)
1781 		return NET_RX_DROP;
1782 
1783 	__get_cpu_var(netdev_rx_stat).total++;
1784 
1785 	skb->h.raw = skb->nh.raw = skb->data;
1786 	skb->mac_len = skb->nh.raw - skb->mac.raw;
1787 
1788 	pt_prev = NULL;
1789 
1790 	rcu_read_lock();
1791 
1792 #ifdef CONFIG_NET_CLS_ACT
1793 	if (skb->tc_verd & TC_NCLS) {
1794 		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
1795 		goto ncls;
1796 	}
1797 #endif
1798 
1799 	list_for_each_entry_rcu(ptype, &ptype_all, list) {
1800 		if (!ptype->dev || ptype->dev == skb->dev) {
1801 			if (pt_prev)
1802 				ret = deliver_skb(skb, pt_prev, orig_dev);
1803 			pt_prev = ptype;
1804 		}
1805 	}
1806 
1807 #ifdef CONFIG_NET_CLS_ACT
1808 	if (pt_prev) {
1809 		ret = deliver_skb(skb, pt_prev, orig_dev);
1810 		pt_prev = NULL; /* noone else should process this after*/
1811 	} else {
1812 		skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
1813 	}
1814 
1815 	ret = ing_filter(skb);
1816 
1817 	if (ret == TC_ACT_SHOT || (ret == TC_ACT_STOLEN)) {
1818 		kfree_skb(skb);
1819 		goto out;
1820 	}
1821 
1822 	skb->tc_verd = 0;
1823 ncls:
1824 #endif
1825 
1826 	handle_diverter(skb);
1827 
1828 	if (handle_bridge(&skb, &pt_prev, &ret, orig_dev))
1829 		goto out;
1830 
1831 	type = skb->protocol;
1832 	list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type)&15], list) {
1833 		if (ptype->type == type &&
1834 		    (!ptype->dev || ptype->dev == skb->dev)) {
1835 			if (pt_prev)
1836 				ret = deliver_skb(skb, pt_prev, orig_dev);
1837 			pt_prev = ptype;
1838 		}
1839 	}
1840 
1841 	if (pt_prev) {
1842 		ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1843 	} else {
1844 		kfree_skb(skb);
1845 		/* Jamal, now you will not able to escape explaining
1846 		 * me how you were going to use this. :-)
1847 		 */
1848 		ret = NET_RX_DROP;
1849 	}
1850 
1851 out:
1852 	rcu_read_unlock();
1853 	return ret;
1854 }
1855 
1856 static int process_backlog(struct net_device *backlog_dev, int *budget)
1857 {
1858 	int work = 0;
1859 	int quota = min(backlog_dev->quota, *budget);
1860 	struct softnet_data *queue = &__get_cpu_var(softnet_data);
1861 	unsigned long start_time = jiffies;
1862 
1863 	backlog_dev->weight = weight_p;
1864 	for (;;) {
1865 		struct sk_buff *skb;
1866 		struct net_device *dev;
1867 
1868 		local_irq_disable();
1869 		skb = __skb_dequeue(&queue->input_pkt_queue);
1870 		if (!skb)
1871 			goto job_done;
1872 		local_irq_enable();
1873 
1874 		dev = skb->dev;
1875 
1876 		netif_receive_skb(skb);
1877 
1878 		dev_put(dev);
1879 
1880 		work++;
1881 
1882 		if (work >= quota || jiffies - start_time > 1)
1883 			break;
1884 
1885 	}
1886 
1887 	backlog_dev->quota -= work;
1888 	*budget -= work;
1889 	return -1;
1890 
1891 job_done:
1892 	backlog_dev->quota -= work;
1893 	*budget -= work;
1894 
1895 	list_del(&backlog_dev->poll_list);
1896 	smp_mb__before_clear_bit();
1897 	netif_poll_enable(backlog_dev);
1898 
1899 	local_irq_enable();
1900 	return 0;
1901 }
1902 
1903 static void net_rx_action(struct softirq_action *h)
1904 {
1905 	struct softnet_data *queue = &__get_cpu_var(softnet_data);
1906 	unsigned long start_time = jiffies;
1907 	int budget = netdev_budget;
1908 	void *have;
1909 
1910 	local_irq_disable();
1911 
1912 	while (!list_empty(&queue->poll_list)) {
1913 		struct net_device *dev;
1914 
1915 		if (budget <= 0 || jiffies - start_time > 1)
1916 			goto softnet_break;
1917 
1918 		local_irq_enable();
1919 
1920 		dev = list_entry(queue->poll_list.next,
1921 				 struct net_device, poll_list);
1922 		have = netpoll_poll_lock(dev);
1923 
1924 		if (dev->quota <= 0 || dev->poll(dev, &budget)) {
1925 			netpoll_poll_unlock(have);
1926 			local_irq_disable();
1927 			list_move_tail(&dev->poll_list, &queue->poll_list);
1928 			if (dev->quota < 0)
1929 				dev->quota += dev->weight;
1930 			else
1931 				dev->quota = dev->weight;
1932 		} else {
1933 			netpoll_poll_unlock(have);
1934 			dev_put(dev);
1935 			local_irq_disable();
1936 		}
1937 	}
1938 out:
1939 #ifdef CONFIG_NET_DMA
1940 	/*
1941 	 * There may not be any more sk_buffs coming right now, so push
1942 	 * any pending DMA copies to hardware
1943 	 */
1944 	if (net_dma_client) {
1945 		struct dma_chan *chan;
1946 		rcu_read_lock();
1947 		list_for_each_entry_rcu(chan, &net_dma_client->channels, client_node)
1948 			dma_async_memcpy_issue_pending(chan);
1949 		rcu_read_unlock();
1950 	}
1951 #endif
1952 	local_irq_enable();
1953 	return;
1954 
1955 softnet_break:
1956 	__get_cpu_var(netdev_rx_stat).time_squeeze++;
1957 	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
1958 	goto out;
1959 }
1960 
1961 static gifconf_func_t * gifconf_list [NPROTO];
1962 
1963 /**
1964  *	register_gifconf	-	register a SIOCGIF handler
1965  *	@family: Address family
1966  *	@gifconf: Function handler
1967  *
1968  *	Register protocol dependent address dumping routines. The handler
1969  *	that is passed must not be freed or reused until it has been replaced
1970  *	by another handler.
1971  */
1972 int register_gifconf(unsigned int family, gifconf_func_t * gifconf)
1973 {
1974 	if (family >= NPROTO)
1975 		return -EINVAL;
1976 	gifconf_list[family] = gifconf;
1977 	return 0;
1978 }
1979 
1980 
1981 /*
1982  *	Map an interface index to its name (SIOCGIFNAME)
1983  */
1984 
1985 /*
1986  *	We need this ioctl for efficient implementation of the
1987  *	if_indextoname() function required by the IPv6 API.  Without
1988  *	it, we would have to search all the interfaces to find a
1989  *	match.  --pb
1990  */
1991 
1992 static int dev_ifname(struct ifreq __user *arg)
1993 {
1994 	struct net_device *dev;
1995 	struct ifreq ifr;
1996 
1997 	/*
1998 	 *	Fetch the caller's info block.
1999 	 */
2000 
2001 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
2002 		return -EFAULT;
2003 
2004 	read_lock(&dev_base_lock);
2005 	dev = __dev_get_by_index(ifr.ifr_ifindex);
2006 	if (!dev) {
2007 		read_unlock(&dev_base_lock);
2008 		return -ENODEV;
2009 	}
2010 
2011 	strcpy(ifr.ifr_name, dev->name);
2012 	read_unlock(&dev_base_lock);
2013 
2014 	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
2015 		return -EFAULT;
2016 	return 0;
2017 }
2018 
2019 /*
2020  *	Perform a SIOCGIFCONF call. This structure will change
2021  *	size eventually, and there is nothing I can do about it.
2022  *	Thus we will need a 'compatibility mode'.
2023  */
2024 
2025 static int dev_ifconf(char __user *arg)
2026 {
2027 	struct ifconf ifc;
2028 	struct net_device *dev;
2029 	char __user *pos;
2030 	int len;
2031 	int total;
2032 	int i;
2033 
2034 	/*
2035 	 *	Fetch the caller's info block.
2036 	 */
2037 
2038 	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
2039 		return -EFAULT;
2040 
2041 	pos = ifc.ifc_buf;
2042 	len = ifc.ifc_len;
2043 
2044 	/*
2045 	 *	Loop over the interfaces, and write an info block for each.
2046 	 */
2047 
2048 	total = 0;
2049 	for (dev = dev_base; dev; dev = dev->next) {
2050 		for (i = 0; i < NPROTO; i++) {
2051 			if (gifconf_list[i]) {
2052 				int done;
2053 				if (!pos)
2054 					done = gifconf_list[i](dev, NULL, 0);
2055 				else
2056 					done = gifconf_list[i](dev, pos + total,
2057 							       len - total);
2058 				if (done < 0)
2059 					return -EFAULT;
2060 				total += done;
2061 			}
2062 		}
2063   	}
2064 
2065 	/*
2066 	 *	All done.  Write the updated control block back to the caller.
2067 	 */
2068 	ifc.ifc_len = total;
2069 
2070 	/*
2071 	 * 	Both BSD and Solaris return 0 here, so we do too.
2072 	 */
2073 	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
2074 }
2075 
2076 #ifdef CONFIG_PROC_FS
2077 /*
2078  *	This is invoked by the /proc filesystem handler to display a device
2079  *	in detail.
2080  */
2081 static __inline__ struct net_device *dev_get_idx(loff_t pos)
2082 {
2083 	struct net_device *dev;
2084 	loff_t i;
2085 
2086 	for (i = 0, dev = dev_base; dev && i < pos; ++i, dev = dev->next);
2087 
2088 	return i == pos ? dev : NULL;
2089 }
2090 
2091 void *dev_seq_start(struct seq_file *seq, loff_t *pos)
2092 {
2093 	read_lock(&dev_base_lock);
2094 	return *pos ? dev_get_idx(*pos - 1) : SEQ_START_TOKEN;
2095 }
2096 
2097 void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2098 {
2099 	++*pos;
2100 	return v == SEQ_START_TOKEN ? dev_base : ((struct net_device *)v)->next;
2101 }
2102 
2103 void dev_seq_stop(struct seq_file *seq, void *v)
2104 {
2105 	read_unlock(&dev_base_lock);
2106 }
2107 
2108 static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
2109 {
2110 	if (dev->get_stats) {
2111 		struct net_device_stats *stats = dev->get_stats(dev);
2112 
2113 		seq_printf(seq, "%6s:%8lu %7lu %4lu %4lu %4lu %5lu %10lu %9lu "
2114 				"%8lu %7lu %4lu %4lu %4lu %5lu %7lu %10lu\n",
2115 			   dev->name, stats->rx_bytes, stats->rx_packets,
2116 			   stats->rx_errors,
2117 			   stats->rx_dropped + stats->rx_missed_errors,
2118 			   stats->rx_fifo_errors,
2119 			   stats->rx_length_errors + stats->rx_over_errors +
2120 			     stats->rx_crc_errors + stats->rx_frame_errors,
2121 			   stats->rx_compressed, stats->multicast,
2122 			   stats->tx_bytes, stats->tx_packets,
2123 			   stats->tx_errors, stats->tx_dropped,
2124 			   stats->tx_fifo_errors, stats->collisions,
2125 			   stats->tx_carrier_errors +
2126 			     stats->tx_aborted_errors +
2127 			     stats->tx_window_errors +
2128 			     stats->tx_heartbeat_errors,
2129 			   stats->tx_compressed);
2130 	} else
2131 		seq_printf(seq, "%6s: No statistics available.\n", dev->name);
2132 }
2133 
2134 /*
2135  *	Called from the PROCfs module. This now uses the new arbitrary sized
2136  *	/proc/net interface to create /proc/net/dev
2137  */
2138 static int dev_seq_show(struct seq_file *seq, void *v)
2139 {
2140 	if (v == SEQ_START_TOKEN)
2141 		seq_puts(seq, "Inter-|   Receive                            "
2142 			      "                    |  Transmit\n"
2143 			      " face |bytes    packets errs drop fifo frame "
2144 			      "compressed multicast|bytes    packets errs "
2145 			      "drop fifo colls carrier compressed\n");
2146 	else
2147 		dev_seq_printf_stats(seq, v);
2148 	return 0;
2149 }
2150 
2151 static struct netif_rx_stats *softnet_get_online(loff_t *pos)
2152 {
2153 	struct netif_rx_stats *rc = NULL;
2154 
2155 	while (*pos < NR_CPUS)
2156 	       	if (cpu_online(*pos)) {
2157 			rc = &per_cpu(netdev_rx_stat, *pos);
2158 			break;
2159 		} else
2160 			++*pos;
2161 	return rc;
2162 }
2163 
2164 static void *softnet_seq_start(struct seq_file *seq, loff_t *pos)
2165 {
2166 	return softnet_get_online(pos);
2167 }
2168 
2169 static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2170 {
2171 	++*pos;
2172 	return softnet_get_online(pos);
2173 }
2174 
2175 static void softnet_seq_stop(struct seq_file *seq, void *v)
2176 {
2177 }
2178 
2179 static int softnet_seq_show(struct seq_file *seq, void *v)
2180 {
2181 	struct netif_rx_stats *s = v;
2182 
2183 	seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x\n",
2184 		   s->total, s->dropped, s->time_squeeze, 0,
2185 		   0, 0, 0, 0, /* was fastroute */
2186 		   s->cpu_collision );
2187 	return 0;
2188 }
2189 
2190 static struct seq_operations dev_seq_ops = {
2191 	.start = dev_seq_start,
2192 	.next  = dev_seq_next,
2193 	.stop  = dev_seq_stop,
2194 	.show  = dev_seq_show,
2195 };
2196 
2197 static int dev_seq_open(struct inode *inode, struct file *file)
2198 {
2199 	return seq_open(file, &dev_seq_ops);
2200 }
2201 
2202 static struct file_operations dev_seq_fops = {
2203 	.owner	 = THIS_MODULE,
2204 	.open    = dev_seq_open,
2205 	.read    = seq_read,
2206 	.llseek  = seq_lseek,
2207 	.release = seq_release,
2208 };
2209 
2210 static struct seq_operations softnet_seq_ops = {
2211 	.start = softnet_seq_start,
2212 	.next  = softnet_seq_next,
2213 	.stop  = softnet_seq_stop,
2214 	.show  = softnet_seq_show,
2215 };
2216 
2217 static int softnet_seq_open(struct inode *inode, struct file *file)
2218 {
2219 	return seq_open(file, &softnet_seq_ops);
2220 }
2221 
2222 static struct file_operations softnet_seq_fops = {
2223 	.owner	 = THIS_MODULE,
2224 	.open    = softnet_seq_open,
2225 	.read    = seq_read,
2226 	.llseek  = seq_lseek,
2227 	.release = seq_release,
2228 };
2229 
2230 #ifdef CONFIG_WIRELESS_EXT
2231 extern int wireless_proc_init(void);
2232 #else
2233 #define wireless_proc_init() 0
2234 #endif
2235 
2236 static int __init dev_proc_init(void)
2237 {
2238 	int rc = -ENOMEM;
2239 
2240 	if (!proc_net_fops_create("dev", S_IRUGO, &dev_seq_fops))
2241 		goto out;
2242 	if (!proc_net_fops_create("softnet_stat", S_IRUGO, &softnet_seq_fops))
2243 		goto out_dev;
2244 	if (wireless_proc_init())
2245 		goto out_softnet;
2246 	rc = 0;
2247 out:
2248 	return rc;
2249 out_softnet:
2250 	proc_net_remove("softnet_stat");
2251 out_dev:
2252 	proc_net_remove("dev");
2253 	goto out;
2254 }
2255 #else
2256 #define dev_proc_init() 0
2257 #endif	/* CONFIG_PROC_FS */
2258 
2259 
2260 /**
2261  *	netdev_set_master	-	set up master/slave pair
2262  *	@slave: slave device
2263  *	@master: new master device
2264  *
2265  *	Changes the master device of the slave. Pass %NULL to break the
2266  *	bonding. The caller must hold the RTNL semaphore. On a failure
2267  *	a negative errno code is returned. On success the reference counts
2268  *	are adjusted, %RTM_NEWLINK is sent to the routing socket and the
2269  *	function returns zero.
2270  */
2271 int netdev_set_master(struct net_device *slave, struct net_device *master)
2272 {
2273 	struct net_device *old = slave->master;
2274 
2275 	ASSERT_RTNL();
2276 
2277 	if (master) {
2278 		if (old)
2279 			return -EBUSY;
2280 		dev_hold(master);
2281 	}
2282 
2283 	slave->master = master;
2284 
2285 	synchronize_net();
2286 
2287 	if (old)
2288 		dev_put(old);
2289 
2290 	if (master)
2291 		slave->flags |= IFF_SLAVE;
2292 	else
2293 		slave->flags &= ~IFF_SLAVE;
2294 
2295 	rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE);
2296 	return 0;
2297 }
2298 
2299 /**
2300  *	dev_set_promiscuity	- update promiscuity count on a device
2301  *	@dev: device
2302  *	@inc: modifier
2303  *
2304  *	Add or remove promiscuity from a device. While the count in the device
2305  *	remains above zero the interface remains promiscuous. Once it hits zero
2306  *	the device reverts back to normal filtering operation. A negative inc
2307  *	value is used to drop promiscuity on the device.
2308  */
2309 void dev_set_promiscuity(struct net_device *dev, int inc)
2310 {
2311 	unsigned short old_flags = dev->flags;
2312 
2313 	if ((dev->promiscuity += inc) == 0)
2314 		dev->flags &= ~IFF_PROMISC;
2315 	else
2316 		dev->flags |= IFF_PROMISC;
2317 	if (dev->flags != old_flags) {
2318 		dev_mc_upload(dev);
2319 		printk(KERN_INFO "device %s %s promiscuous mode\n",
2320 		       dev->name, (dev->flags & IFF_PROMISC) ? "entered" :
2321 		       					       "left");
2322 		audit_log(current->audit_context, GFP_ATOMIC,
2323 			AUDIT_ANOM_PROMISCUOUS,
2324 			"dev=%s prom=%d old_prom=%d auid=%u",
2325 			dev->name, (dev->flags & IFF_PROMISC),
2326 			(old_flags & IFF_PROMISC),
2327 			audit_get_loginuid(current->audit_context));
2328 	}
2329 }
2330 
2331 /**
2332  *	dev_set_allmulti	- update allmulti count on a device
2333  *	@dev: device
2334  *	@inc: modifier
2335  *
2336  *	Add or remove reception of all multicast frames to a device. While the
2337  *	count in the device remains above zero the interface remains listening
2338  *	to all interfaces. Once it hits zero the device reverts back to normal
2339  *	filtering operation. A negative @inc value is used to drop the counter
2340  *	when releasing a resource needing all multicasts.
2341  */
2342 
2343 void dev_set_allmulti(struct net_device *dev, int inc)
2344 {
2345 	unsigned short old_flags = dev->flags;
2346 
2347 	dev->flags |= IFF_ALLMULTI;
2348 	if ((dev->allmulti += inc) == 0)
2349 		dev->flags &= ~IFF_ALLMULTI;
2350 	if (dev->flags ^ old_flags)
2351 		dev_mc_upload(dev);
2352 }
2353 
2354 unsigned dev_get_flags(const struct net_device *dev)
2355 {
2356 	unsigned flags;
2357 
2358 	flags = (dev->flags & ~(IFF_PROMISC |
2359 				IFF_ALLMULTI |
2360 				IFF_RUNNING |
2361 				IFF_LOWER_UP |
2362 				IFF_DORMANT)) |
2363 		(dev->gflags & (IFF_PROMISC |
2364 				IFF_ALLMULTI));
2365 
2366 	if (netif_running(dev)) {
2367 		if (netif_oper_up(dev))
2368 			flags |= IFF_RUNNING;
2369 		if (netif_carrier_ok(dev))
2370 			flags |= IFF_LOWER_UP;
2371 		if (netif_dormant(dev))
2372 			flags |= IFF_DORMANT;
2373 	}
2374 
2375 	return flags;
2376 }
2377 
2378 int dev_change_flags(struct net_device *dev, unsigned flags)
2379 {
2380 	int ret;
2381 	int old_flags = dev->flags;
2382 
2383 	/*
2384 	 *	Set the flags on our device.
2385 	 */
2386 
2387 	dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
2388 			       IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
2389 			       IFF_AUTOMEDIA)) |
2390 		     (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
2391 				    IFF_ALLMULTI));
2392 
2393 	/*
2394 	 *	Load in the correct multicast list now the flags have changed.
2395 	 */
2396 
2397 	dev_mc_upload(dev);
2398 
2399 	/*
2400 	 *	Have we downed the interface. We handle IFF_UP ourselves
2401 	 *	according to user attempts to set it, rather than blindly
2402 	 *	setting it.
2403 	 */
2404 
2405 	ret = 0;
2406 	if ((old_flags ^ flags) & IFF_UP) {	/* Bit is different  ? */
2407 		ret = ((old_flags & IFF_UP) ? dev_close : dev_open)(dev);
2408 
2409 		if (!ret)
2410 			dev_mc_upload(dev);
2411 	}
2412 
2413 	if (dev->flags & IFF_UP &&
2414 	    ((old_flags ^ dev->flags) &~ (IFF_UP | IFF_PROMISC | IFF_ALLMULTI |
2415 					  IFF_VOLATILE)))
2416 		raw_notifier_call_chain(&netdev_chain,
2417 				NETDEV_CHANGE, dev);
2418 
2419 	if ((flags ^ dev->gflags) & IFF_PROMISC) {
2420 		int inc = (flags & IFF_PROMISC) ? +1 : -1;
2421 		dev->gflags ^= IFF_PROMISC;
2422 		dev_set_promiscuity(dev, inc);
2423 	}
2424 
2425 	/* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
2426 	   is important. Some (broken) drivers set IFF_PROMISC, when
2427 	   IFF_ALLMULTI is requested not asking us and not reporting.
2428 	 */
2429 	if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
2430 		int inc = (flags & IFF_ALLMULTI) ? +1 : -1;
2431 		dev->gflags ^= IFF_ALLMULTI;
2432 		dev_set_allmulti(dev, inc);
2433 	}
2434 
2435 	if (old_flags ^ dev->flags)
2436 		rtmsg_ifinfo(RTM_NEWLINK, dev, old_flags ^ dev->flags);
2437 
2438 	return ret;
2439 }
2440 
2441 int dev_set_mtu(struct net_device *dev, int new_mtu)
2442 {
2443 	int err;
2444 
2445 	if (new_mtu == dev->mtu)
2446 		return 0;
2447 
2448 	/*	MTU must be positive.	 */
2449 	if (new_mtu < 0)
2450 		return -EINVAL;
2451 
2452 	if (!netif_device_present(dev))
2453 		return -ENODEV;
2454 
2455 	err = 0;
2456 	if (dev->change_mtu)
2457 		err = dev->change_mtu(dev, new_mtu);
2458 	else
2459 		dev->mtu = new_mtu;
2460 	if (!err && dev->flags & IFF_UP)
2461 		raw_notifier_call_chain(&netdev_chain,
2462 				NETDEV_CHANGEMTU, dev);
2463 	return err;
2464 }
2465 
2466 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
2467 {
2468 	int err;
2469 
2470 	if (!dev->set_mac_address)
2471 		return -EOPNOTSUPP;
2472 	if (sa->sa_family != dev->type)
2473 		return -EINVAL;
2474 	if (!netif_device_present(dev))
2475 		return -ENODEV;
2476 	err = dev->set_mac_address(dev, sa);
2477 	if (!err)
2478 		raw_notifier_call_chain(&netdev_chain,
2479 				NETDEV_CHANGEADDR, dev);
2480 	return err;
2481 }
2482 
2483 /*
2484  *	Perform the SIOCxIFxxx calls.
2485  */
2486 static int dev_ifsioc(struct ifreq *ifr, unsigned int cmd)
2487 {
2488 	int err;
2489 	struct net_device *dev = __dev_get_by_name(ifr->ifr_name);
2490 
2491 	if (!dev)
2492 		return -ENODEV;
2493 
2494 	switch (cmd) {
2495 		case SIOCGIFFLAGS:	/* Get interface flags */
2496 			ifr->ifr_flags = dev_get_flags(dev);
2497 			return 0;
2498 
2499 		case SIOCSIFFLAGS:	/* Set interface flags */
2500 			return dev_change_flags(dev, ifr->ifr_flags);
2501 
2502 		case SIOCGIFMETRIC:	/* Get the metric on the interface
2503 					   (currently unused) */
2504 			ifr->ifr_metric = 0;
2505 			return 0;
2506 
2507 		case SIOCSIFMETRIC:	/* Set the metric on the interface
2508 					   (currently unused) */
2509 			return -EOPNOTSUPP;
2510 
2511 		case SIOCGIFMTU:	/* Get the MTU of a device */
2512 			ifr->ifr_mtu = dev->mtu;
2513 			return 0;
2514 
2515 		case SIOCSIFMTU:	/* Set the MTU of a device */
2516 			return dev_set_mtu(dev, ifr->ifr_mtu);
2517 
2518 		case SIOCGIFHWADDR:
2519 			if (!dev->addr_len)
2520 				memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data);
2521 			else
2522 				memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
2523 				       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
2524 			ifr->ifr_hwaddr.sa_family = dev->type;
2525 			return 0;
2526 
2527 		case SIOCSIFHWADDR:
2528 			return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
2529 
2530 		case SIOCSIFHWBROADCAST:
2531 			if (ifr->ifr_hwaddr.sa_family != dev->type)
2532 				return -EINVAL;
2533 			memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
2534 			       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
2535 			raw_notifier_call_chain(&netdev_chain,
2536 					    NETDEV_CHANGEADDR, dev);
2537 			return 0;
2538 
2539 		case SIOCGIFMAP:
2540 			ifr->ifr_map.mem_start = dev->mem_start;
2541 			ifr->ifr_map.mem_end   = dev->mem_end;
2542 			ifr->ifr_map.base_addr = dev->base_addr;
2543 			ifr->ifr_map.irq       = dev->irq;
2544 			ifr->ifr_map.dma       = dev->dma;
2545 			ifr->ifr_map.port      = dev->if_port;
2546 			return 0;
2547 
2548 		case SIOCSIFMAP:
2549 			if (dev->set_config) {
2550 				if (!netif_device_present(dev))
2551 					return -ENODEV;
2552 				return dev->set_config(dev, &ifr->ifr_map);
2553 			}
2554 			return -EOPNOTSUPP;
2555 
2556 		case SIOCADDMULTI:
2557 			if (!dev->set_multicast_list ||
2558 			    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
2559 				return -EINVAL;
2560 			if (!netif_device_present(dev))
2561 				return -ENODEV;
2562 			return dev_mc_add(dev, ifr->ifr_hwaddr.sa_data,
2563 					  dev->addr_len, 1);
2564 
2565 		case SIOCDELMULTI:
2566 			if (!dev->set_multicast_list ||
2567 			    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
2568 				return -EINVAL;
2569 			if (!netif_device_present(dev))
2570 				return -ENODEV;
2571 			return dev_mc_delete(dev, ifr->ifr_hwaddr.sa_data,
2572 					     dev->addr_len, 1);
2573 
2574 		case SIOCGIFINDEX:
2575 			ifr->ifr_ifindex = dev->ifindex;
2576 			return 0;
2577 
2578 		case SIOCGIFTXQLEN:
2579 			ifr->ifr_qlen = dev->tx_queue_len;
2580 			return 0;
2581 
2582 		case SIOCSIFTXQLEN:
2583 			if (ifr->ifr_qlen < 0)
2584 				return -EINVAL;
2585 			dev->tx_queue_len = ifr->ifr_qlen;
2586 			return 0;
2587 
2588 		case SIOCSIFNAME:
2589 			ifr->ifr_newname[IFNAMSIZ-1] = '\0';
2590 			return dev_change_name(dev, ifr->ifr_newname);
2591 
2592 		/*
2593 		 *	Unknown or private ioctl
2594 		 */
2595 
2596 		default:
2597 			if ((cmd >= SIOCDEVPRIVATE &&
2598 			    cmd <= SIOCDEVPRIVATE + 15) ||
2599 			    cmd == SIOCBONDENSLAVE ||
2600 			    cmd == SIOCBONDRELEASE ||
2601 			    cmd == SIOCBONDSETHWADDR ||
2602 			    cmd == SIOCBONDSLAVEINFOQUERY ||
2603 			    cmd == SIOCBONDINFOQUERY ||
2604 			    cmd == SIOCBONDCHANGEACTIVE ||
2605 			    cmd == SIOCGMIIPHY ||
2606 			    cmd == SIOCGMIIREG ||
2607 			    cmd == SIOCSMIIREG ||
2608 			    cmd == SIOCBRADDIF ||
2609 			    cmd == SIOCBRDELIF ||
2610 			    cmd == SIOCWANDEV) {
2611 				err = -EOPNOTSUPP;
2612 				if (dev->do_ioctl) {
2613 					if (netif_device_present(dev))
2614 						err = dev->do_ioctl(dev, ifr,
2615 								    cmd);
2616 					else
2617 						err = -ENODEV;
2618 				}
2619 			} else
2620 				err = -EINVAL;
2621 
2622 	}
2623 	return err;
2624 }
2625 
2626 /*
2627  *	This function handles all "interface"-type I/O control requests. The actual
2628  *	'doing' part of this is dev_ifsioc above.
2629  */
2630 
2631 /**
2632  *	dev_ioctl	-	network device ioctl
2633  *	@cmd: command to issue
2634  *	@arg: pointer to a struct ifreq in user space
2635  *
2636  *	Issue ioctl functions to devices. This is normally called by the
2637  *	user space syscall interfaces but can sometimes be useful for
2638  *	other purposes. The return value is the return from the syscall if
2639  *	positive or a negative errno code on error.
2640  */
2641 
2642 int dev_ioctl(unsigned int cmd, void __user *arg)
2643 {
2644 	struct ifreq ifr;
2645 	int ret;
2646 	char *colon;
2647 
2648 	/* One special case: SIOCGIFCONF takes ifconf argument
2649 	   and requires shared lock, because it sleeps writing
2650 	   to user space.
2651 	 */
2652 
2653 	if (cmd == SIOCGIFCONF) {
2654 		rtnl_lock();
2655 		ret = dev_ifconf((char __user *) arg);
2656 		rtnl_unlock();
2657 		return ret;
2658 	}
2659 	if (cmd == SIOCGIFNAME)
2660 		return dev_ifname((struct ifreq __user *)arg);
2661 
2662 	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
2663 		return -EFAULT;
2664 
2665 	ifr.ifr_name[IFNAMSIZ-1] = 0;
2666 
2667 	colon = strchr(ifr.ifr_name, ':');
2668 	if (colon)
2669 		*colon = 0;
2670 
2671 	/*
2672 	 *	See which interface the caller is talking about.
2673 	 */
2674 
2675 	switch (cmd) {
2676 		/*
2677 		 *	These ioctl calls:
2678 		 *	- can be done by all.
2679 		 *	- atomic and do not require locking.
2680 		 *	- return a value
2681 		 */
2682 		case SIOCGIFFLAGS:
2683 		case SIOCGIFMETRIC:
2684 		case SIOCGIFMTU:
2685 		case SIOCGIFHWADDR:
2686 		case SIOCGIFSLAVE:
2687 		case SIOCGIFMAP:
2688 		case SIOCGIFINDEX:
2689 		case SIOCGIFTXQLEN:
2690 			dev_load(ifr.ifr_name);
2691 			read_lock(&dev_base_lock);
2692 			ret = dev_ifsioc(&ifr, cmd);
2693 			read_unlock(&dev_base_lock);
2694 			if (!ret) {
2695 				if (colon)
2696 					*colon = ':';
2697 				if (copy_to_user(arg, &ifr,
2698 						 sizeof(struct ifreq)))
2699 					ret = -EFAULT;
2700 			}
2701 			return ret;
2702 
2703 		case SIOCETHTOOL:
2704 			dev_load(ifr.ifr_name);
2705 			rtnl_lock();
2706 			ret = dev_ethtool(&ifr);
2707 			rtnl_unlock();
2708 			if (!ret) {
2709 				if (colon)
2710 					*colon = ':';
2711 				if (copy_to_user(arg, &ifr,
2712 						 sizeof(struct ifreq)))
2713 					ret = -EFAULT;
2714 			}
2715 			return ret;
2716 
2717 		/*
2718 		 *	These ioctl calls:
2719 		 *	- require superuser power.
2720 		 *	- require strict serialization.
2721 		 *	- return a value
2722 		 */
2723 		case SIOCGMIIPHY:
2724 		case SIOCGMIIREG:
2725 		case SIOCSIFNAME:
2726 			if (!capable(CAP_NET_ADMIN))
2727 				return -EPERM;
2728 			dev_load(ifr.ifr_name);
2729 			rtnl_lock();
2730 			ret = dev_ifsioc(&ifr, cmd);
2731 			rtnl_unlock();
2732 			if (!ret) {
2733 				if (colon)
2734 					*colon = ':';
2735 				if (copy_to_user(arg, &ifr,
2736 						 sizeof(struct ifreq)))
2737 					ret = -EFAULT;
2738 			}
2739 			return ret;
2740 
2741 		/*
2742 		 *	These ioctl calls:
2743 		 *	- require superuser power.
2744 		 *	- require strict serialization.
2745 		 *	- do not return a value
2746 		 */
2747 		case SIOCSIFFLAGS:
2748 		case SIOCSIFMETRIC:
2749 		case SIOCSIFMTU:
2750 		case SIOCSIFMAP:
2751 		case SIOCSIFHWADDR:
2752 		case SIOCSIFSLAVE:
2753 		case SIOCADDMULTI:
2754 		case SIOCDELMULTI:
2755 		case SIOCSIFHWBROADCAST:
2756 		case SIOCSIFTXQLEN:
2757 		case SIOCSMIIREG:
2758 		case SIOCBONDENSLAVE:
2759 		case SIOCBONDRELEASE:
2760 		case SIOCBONDSETHWADDR:
2761 		case SIOCBONDCHANGEACTIVE:
2762 		case SIOCBRADDIF:
2763 		case SIOCBRDELIF:
2764 			if (!capable(CAP_NET_ADMIN))
2765 				return -EPERM;
2766 			/* fall through */
2767 		case SIOCBONDSLAVEINFOQUERY:
2768 		case SIOCBONDINFOQUERY:
2769 			dev_load(ifr.ifr_name);
2770 			rtnl_lock();
2771 			ret = dev_ifsioc(&ifr, cmd);
2772 			rtnl_unlock();
2773 			return ret;
2774 
2775 		case SIOCGIFMEM:
2776 			/* Get the per device memory space. We can add this but
2777 			 * currently do not support it */
2778 		case SIOCSIFMEM:
2779 			/* Set the per device memory buffer space.
2780 			 * Not applicable in our case */
2781 		case SIOCSIFLINK:
2782 			return -EINVAL;
2783 
2784 		/*
2785 		 *	Unknown or private ioctl.
2786 		 */
2787 		default:
2788 			if (cmd == SIOCWANDEV ||
2789 			    (cmd >= SIOCDEVPRIVATE &&
2790 			     cmd <= SIOCDEVPRIVATE + 15)) {
2791 				dev_load(ifr.ifr_name);
2792 				rtnl_lock();
2793 				ret = dev_ifsioc(&ifr, cmd);
2794 				rtnl_unlock();
2795 				if (!ret && copy_to_user(arg, &ifr,
2796 							 sizeof(struct ifreq)))
2797 					ret = -EFAULT;
2798 				return ret;
2799 			}
2800 #ifdef CONFIG_WIRELESS_EXT
2801 			/* Take care of Wireless Extensions */
2802 			if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
2803 				/* If command is `set a parameter', or
2804 				 * `get the encoding parameters', check if
2805 				 * the user has the right to do it */
2806 				if (IW_IS_SET(cmd) || cmd == SIOCGIWENCODE
2807 				    || cmd == SIOCGIWENCODEEXT) {
2808 					if (!capable(CAP_NET_ADMIN))
2809 						return -EPERM;
2810 				}
2811 				dev_load(ifr.ifr_name);
2812 				rtnl_lock();
2813 				/* Follow me in net/core/wireless.c */
2814 				ret = wireless_process_ioctl(&ifr, cmd);
2815 				rtnl_unlock();
2816 				if (IW_IS_GET(cmd) &&
2817 				    copy_to_user(arg, &ifr,
2818 					    	 sizeof(struct ifreq)))
2819 					ret = -EFAULT;
2820 				return ret;
2821 			}
2822 #endif	/* CONFIG_WIRELESS_EXT */
2823 			return -EINVAL;
2824 	}
2825 }
2826 
2827 
2828 /**
2829  *	dev_new_index	-	allocate an ifindex
2830  *
2831  *	Returns a suitable unique value for a new device interface
2832  *	number.  The caller must hold the rtnl semaphore or the
2833  *	dev_base_lock to be sure it remains unique.
2834  */
2835 static int dev_new_index(void)
2836 {
2837 	static int ifindex;
2838 	for (;;) {
2839 		if (++ifindex <= 0)
2840 			ifindex = 1;
2841 		if (!__dev_get_by_index(ifindex))
2842 			return ifindex;
2843 	}
2844 }
2845 
2846 static int dev_boot_phase = 1;
2847 
2848 /* Delayed registration/unregisteration */
2849 static DEFINE_SPINLOCK(net_todo_list_lock);
2850 static struct list_head net_todo_list = LIST_HEAD_INIT(net_todo_list);
2851 
2852 static inline void net_set_todo(struct net_device *dev)
2853 {
2854 	spin_lock(&net_todo_list_lock);
2855 	list_add_tail(&dev->todo_list, &net_todo_list);
2856 	spin_unlock(&net_todo_list_lock);
2857 }
2858 
2859 /**
2860  *	register_netdevice	- register a network device
2861  *	@dev: device to register
2862  *
2863  *	Take a completed network device structure and add it to the kernel
2864  *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
2865  *	chain. 0 is returned on success. A negative errno code is returned
2866  *	on a failure to set up the device, or if the name is a duplicate.
2867  *
2868  *	Callers must hold the rtnl semaphore. You may want
2869  *	register_netdev() instead of this.
2870  *
2871  *	BUGS:
2872  *	The locking appears insufficient to guarantee two parallel registers
2873  *	will not get the same name.
2874  */
2875 
2876 int register_netdevice(struct net_device *dev)
2877 {
2878 	struct hlist_head *head;
2879 	struct hlist_node *p;
2880 	int ret;
2881 
2882 	BUG_ON(dev_boot_phase);
2883 	ASSERT_RTNL();
2884 
2885 	might_sleep();
2886 
2887 	/* When net_device's are persistent, this will be fatal. */
2888 	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
2889 
2890 	spin_lock_init(&dev->queue_lock);
2891 	spin_lock_init(&dev->_xmit_lock);
2892 	dev->xmit_lock_owner = -1;
2893 #ifdef CONFIG_NET_CLS_ACT
2894 	spin_lock_init(&dev->ingress_lock);
2895 #endif
2896 
2897 	ret = alloc_divert_blk(dev);
2898 	if (ret)
2899 		goto out;
2900 
2901 	dev->iflink = -1;
2902 
2903 	/* Init, if this function is available */
2904 	if (dev->init) {
2905 		ret = dev->init(dev);
2906 		if (ret) {
2907 			if (ret > 0)
2908 				ret = -EIO;
2909 			goto out_err;
2910 		}
2911 	}
2912 
2913 	if (!dev_valid_name(dev->name)) {
2914 		ret = -EINVAL;
2915 		goto out_err;
2916 	}
2917 
2918 	dev->ifindex = dev_new_index();
2919 	if (dev->iflink == -1)
2920 		dev->iflink = dev->ifindex;
2921 
2922 	/* Check for existence of name */
2923 	head = dev_name_hash(dev->name);
2924 	hlist_for_each(p, head) {
2925 		struct net_device *d
2926 			= hlist_entry(p, struct net_device, name_hlist);
2927 		if (!strncmp(d->name, dev->name, IFNAMSIZ)) {
2928 			ret = -EEXIST;
2929  			goto out_err;
2930 		}
2931  	}
2932 
2933 	/* Fix illegal SG+CSUM combinations. */
2934 	if ((dev->features & NETIF_F_SG) &&
2935 	    !(dev->features & NETIF_F_ALL_CSUM)) {
2936 		printk(KERN_NOTICE "%s: Dropping NETIF_F_SG since no checksum feature.\n",
2937 		       dev->name);
2938 		dev->features &= ~NETIF_F_SG;
2939 	}
2940 
2941 	/* TSO requires that SG is present as well. */
2942 	if ((dev->features & NETIF_F_TSO) &&
2943 	    !(dev->features & NETIF_F_SG)) {
2944 		printk(KERN_NOTICE "%s: Dropping NETIF_F_TSO since no SG feature.\n",
2945 		       dev->name);
2946 		dev->features &= ~NETIF_F_TSO;
2947 	}
2948 	if (dev->features & NETIF_F_UFO) {
2949 		if (!(dev->features & NETIF_F_HW_CSUM)) {
2950 			printk(KERN_ERR "%s: Dropping NETIF_F_UFO since no "
2951 					"NETIF_F_HW_CSUM feature.\n",
2952 							dev->name);
2953 			dev->features &= ~NETIF_F_UFO;
2954 		}
2955 		if (!(dev->features & NETIF_F_SG)) {
2956 			printk(KERN_ERR "%s: Dropping NETIF_F_UFO since no "
2957 					"NETIF_F_SG feature.\n",
2958 					dev->name);
2959 			dev->features &= ~NETIF_F_UFO;
2960 		}
2961 	}
2962 
2963 	/*
2964 	 *	nil rebuild_header routine,
2965 	 *	that should be never called and used as just bug trap.
2966 	 */
2967 
2968 	if (!dev->rebuild_header)
2969 		dev->rebuild_header = default_rebuild_header;
2970 
2971 	ret = netdev_register_sysfs(dev);
2972 	if (ret)
2973 		goto out_err;
2974 	dev->reg_state = NETREG_REGISTERED;
2975 
2976 	/*
2977 	 *	Default initial state at registry is that the
2978 	 *	device is present.
2979 	 */
2980 
2981 	set_bit(__LINK_STATE_PRESENT, &dev->state);
2982 
2983 	dev->next = NULL;
2984 	dev_init_scheduler(dev);
2985 	write_lock_bh(&dev_base_lock);
2986 	*dev_tail = dev;
2987 	dev_tail = &dev->next;
2988 	hlist_add_head(&dev->name_hlist, head);
2989 	hlist_add_head(&dev->index_hlist, dev_index_hash(dev->ifindex));
2990 	dev_hold(dev);
2991 	write_unlock_bh(&dev_base_lock);
2992 
2993 	/* Notify protocols, that a new device appeared. */
2994 	raw_notifier_call_chain(&netdev_chain, NETDEV_REGISTER, dev);
2995 
2996 	ret = 0;
2997 
2998 out:
2999 	return ret;
3000 out_err:
3001 	free_divert_blk(dev);
3002 	goto out;
3003 }
3004 
3005 /**
3006  *	register_netdev	- register a network device
3007  *	@dev: device to register
3008  *
3009  *	Take a completed network device structure and add it to the kernel
3010  *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
3011  *	chain. 0 is returned on success. A negative errno code is returned
3012  *	on a failure to set up the device, or if the name is a duplicate.
3013  *
3014  *	This is a wrapper around register_netdev that takes the rtnl semaphore
3015  *	and expands the device name if you passed a format string to
3016  *	alloc_netdev.
3017  */
3018 int register_netdev(struct net_device *dev)
3019 {
3020 	int err;
3021 
3022 	rtnl_lock();
3023 
3024 	/*
3025 	 * If the name is a format string the caller wants us to do a
3026 	 * name allocation.
3027 	 */
3028 	if (strchr(dev->name, '%')) {
3029 		err = dev_alloc_name(dev, dev->name);
3030 		if (err < 0)
3031 			goto out;
3032 	}
3033 
3034 	/*
3035 	 * Back compatibility hook. Kill this one in 2.5
3036 	 */
3037 	if (dev->name[0] == 0 || dev->name[0] == ' ') {
3038 		err = dev_alloc_name(dev, "eth%d");
3039 		if (err < 0)
3040 			goto out;
3041 	}
3042 
3043 	err = register_netdevice(dev);
3044 out:
3045 	rtnl_unlock();
3046 	return err;
3047 }
3048 EXPORT_SYMBOL(register_netdev);
3049 
3050 /*
3051  * netdev_wait_allrefs - wait until all references are gone.
3052  *
3053  * This is called when unregistering network devices.
3054  *
3055  * Any protocol or device that holds a reference should register
3056  * for netdevice notification, and cleanup and put back the
3057  * reference if they receive an UNREGISTER event.
3058  * We can get stuck here if buggy protocols don't correctly
3059  * call dev_put.
3060  */
3061 static void netdev_wait_allrefs(struct net_device *dev)
3062 {
3063 	unsigned long rebroadcast_time, warning_time;
3064 
3065 	rebroadcast_time = warning_time = jiffies;
3066 	while (atomic_read(&dev->refcnt) != 0) {
3067 		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
3068 			rtnl_lock();
3069 
3070 			/* Rebroadcast unregister notification */
3071 			raw_notifier_call_chain(&netdev_chain,
3072 					    NETDEV_UNREGISTER, dev);
3073 
3074 			if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
3075 				     &dev->state)) {
3076 				/* We must not have linkwatch events
3077 				 * pending on unregister. If this
3078 				 * happens, we simply run the queue
3079 				 * unscheduled, resulting in a noop
3080 				 * for this device.
3081 				 */
3082 				linkwatch_run_queue();
3083 			}
3084 
3085 			__rtnl_unlock();
3086 
3087 			rebroadcast_time = jiffies;
3088 		}
3089 
3090 		msleep(250);
3091 
3092 		if (time_after(jiffies, warning_time + 10 * HZ)) {
3093 			printk(KERN_EMERG "unregister_netdevice: "
3094 			       "waiting for %s to become free. Usage "
3095 			       "count = %d\n",
3096 			       dev->name, atomic_read(&dev->refcnt));
3097 			warning_time = jiffies;
3098 		}
3099 	}
3100 }
3101 
3102 /* The sequence is:
3103  *
3104  *	rtnl_lock();
3105  *	...
3106  *	register_netdevice(x1);
3107  *	register_netdevice(x2);
3108  *	...
3109  *	unregister_netdevice(y1);
3110  *	unregister_netdevice(y2);
3111  *      ...
3112  *	rtnl_unlock();
3113  *	free_netdev(y1);
3114  *	free_netdev(y2);
3115  *
3116  * We are invoked by rtnl_unlock() after it drops the semaphore.
3117  * This allows us to deal with problems:
3118  * 1) We can delete sysfs objects which invoke hotplug
3119  *    without deadlocking with linkwatch via keventd.
3120  * 2) Since we run with the RTNL semaphore not held, we can sleep
3121  *    safely in order to wait for the netdev refcnt to drop to zero.
3122  */
3123 static DEFINE_MUTEX(net_todo_run_mutex);
3124 void netdev_run_todo(void)
3125 {
3126 	struct list_head list;
3127 
3128 	/* Need to guard against multiple cpu's getting out of order. */
3129 	mutex_lock(&net_todo_run_mutex);
3130 
3131 	/* Not safe to do outside the semaphore.  We must not return
3132 	 * until all unregister events invoked by the local processor
3133 	 * have been completed (either by this todo run, or one on
3134 	 * another cpu).
3135 	 */
3136 	if (list_empty(&net_todo_list))
3137 		goto out;
3138 
3139 	/* Snapshot list, allow later requests */
3140 	spin_lock(&net_todo_list_lock);
3141 	list_replace_init(&net_todo_list, &list);
3142 	spin_unlock(&net_todo_list_lock);
3143 
3144 	while (!list_empty(&list)) {
3145 		struct net_device *dev
3146 			= list_entry(list.next, struct net_device, todo_list);
3147 		list_del(&dev->todo_list);
3148 
3149 		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
3150 			printk(KERN_ERR "network todo '%s' but state %d\n",
3151 			       dev->name, dev->reg_state);
3152 			dump_stack();
3153 			continue;
3154 		}
3155 
3156 		netdev_unregister_sysfs(dev);
3157 		dev->reg_state = NETREG_UNREGISTERED;
3158 
3159 		netdev_wait_allrefs(dev);
3160 
3161 		/* paranoia */
3162 		BUG_ON(atomic_read(&dev->refcnt));
3163 		BUG_TRAP(!dev->ip_ptr);
3164 		BUG_TRAP(!dev->ip6_ptr);
3165 		BUG_TRAP(!dev->dn_ptr);
3166 
3167 		/* It must be the very last action,
3168 		 * after this 'dev' may point to freed up memory.
3169 		 */
3170 		if (dev->destructor)
3171 			dev->destructor(dev);
3172 	}
3173 
3174 out:
3175 	mutex_unlock(&net_todo_run_mutex);
3176 }
3177 
3178 /**
3179  *	alloc_netdev - allocate network device
3180  *	@sizeof_priv:	size of private data to allocate space for
3181  *	@name:		device name format string
3182  *	@setup:		callback to initialize device
3183  *
3184  *	Allocates a struct net_device with private data area for driver use
3185  *	and performs basic initialization.
3186  */
3187 struct net_device *alloc_netdev(int sizeof_priv, const char *name,
3188 		void (*setup)(struct net_device *))
3189 {
3190 	void *p;
3191 	struct net_device *dev;
3192 	int alloc_size;
3193 
3194 	/* ensure 32-byte alignment of both the device and private area */
3195 	alloc_size = (sizeof(*dev) + NETDEV_ALIGN_CONST) & ~NETDEV_ALIGN_CONST;
3196 	alloc_size += sizeof_priv + NETDEV_ALIGN_CONST;
3197 
3198 	p = kzalloc(alloc_size, GFP_KERNEL);
3199 	if (!p) {
3200 		printk(KERN_ERR "alloc_dev: Unable to allocate device.\n");
3201 		return NULL;
3202 	}
3203 
3204 	dev = (struct net_device *)
3205 		(((long)p + NETDEV_ALIGN_CONST) & ~NETDEV_ALIGN_CONST);
3206 	dev->padded = (char *)dev - (char *)p;
3207 
3208 	if (sizeof_priv)
3209 		dev->priv = netdev_priv(dev);
3210 
3211 	setup(dev);
3212 	strcpy(dev->name, name);
3213 	return dev;
3214 }
3215 EXPORT_SYMBOL(alloc_netdev);
3216 
3217 /**
3218  *	free_netdev - free network device
3219  *	@dev: device
3220  *
3221  *	This function does the last stage of destroying an allocated device
3222  * 	interface. The reference to the device object is released.
3223  *	If this is the last reference then it will be freed.
3224  */
3225 void free_netdev(struct net_device *dev)
3226 {
3227 #ifdef CONFIG_SYSFS
3228 	/*  Compatibility with error handling in drivers */
3229 	if (dev->reg_state == NETREG_UNINITIALIZED) {
3230 		kfree((char *)dev - dev->padded);
3231 		return;
3232 	}
3233 
3234 	BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
3235 	dev->reg_state = NETREG_RELEASED;
3236 
3237 	/* will free via class release */
3238 	class_device_put(&dev->class_dev);
3239 #else
3240 	kfree((char *)dev - dev->padded);
3241 #endif
3242 }
3243 
3244 /* Synchronize with packet receive processing. */
3245 void synchronize_net(void)
3246 {
3247 	might_sleep();
3248 	synchronize_rcu();
3249 }
3250 
3251 /**
3252  *	unregister_netdevice - remove device from the kernel
3253  *	@dev: device
3254  *
3255  *	This function shuts down a device interface and removes it
3256  *	from the kernel tables. On success 0 is returned, on a failure
3257  *	a negative errno code is returned.
3258  *
3259  *	Callers must hold the rtnl semaphore.  You may want
3260  *	unregister_netdev() instead of this.
3261  */
3262 
3263 int unregister_netdevice(struct net_device *dev)
3264 {
3265 	struct net_device *d, **dp;
3266 
3267 	BUG_ON(dev_boot_phase);
3268 	ASSERT_RTNL();
3269 
3270 	/* Some devices call without registering for initialization unwind. */
3271 	if (dev->reg_state == NETREG_UNINITIALIZED) {
3272 		printk(KERN_DEBUG "unregister_netdevice: device %s/%p never "
3273 				  "was registered\n", dev->name, dev);
3274 		return -ENODEV;
3275 	}
3276 
3277 	BUG_ON(dev->reg_state != NETREG_REGISTERED);
3278 
3279 	/* If device is running, close it first. */
3280 	if (dev->flags & IFF_UP)
3281 		dev_close(dev);
3282 
3283 	/* And unlink it from device chain. */
3284 	for (dp = &dev_base; (d = *dp) != NULL; dp = &d->next) {
3285 		if (d == dev) {
3286 			write_lock_bh(&dev_base_lock);
3287 			hlist_del(&dev->name_hlist);
3288 			hlist_del(&dev->index_hlist);
3289 			if (dev_tail == &dev->next)
3290 				dev_tail = dp;
3291 			*dp = d->next;
3292 			write_unlock_bh(&dev_base_lock);
3293 			break;
3294 		}
3295 	}
3296 	if (!d) {
3297 		printk(KERN_ERR "unregister net_device: '%s' not found\n",
3298 		       dev->name);
3299 		return -ENODEV;
3300 	}
3301 
3302 	dev->reg_state = NETREG_UNREGISTERING;
3303 
3304 	synchronize_net();
3305 
3306 	/* Shutdown queueing discipline. */
3307 	dev_shutdown(dev);
3308 
3309 
3310 	/* Notify protocols, that we are about to destroy
3311 	   this device. They should clean all the things.
3312 	*/
3313 	raw_notifier_call_chain(&netdev_chain, NETDEV_UNREGISTER, dev);
3314 
3315 	/*
3316 	 *	Flush the multicast chain
3317 	 */
3318 	dev_mc_discard(dev);
3319 
3320 	if (dev->uninit)
3321 		dev->uninit(dev);
3322 
3323 	/* Notifier chain MUST detach us from master device. */
3324 	BUG_TRAP(!dev->master);
3325 
3326 	free_divert_blk(dev);
3327 
3328 	/* Finish processing unregister after unlock */
3329 	net_set_todo(dev);
3330 
3331 	synchronize_net();
3332 
3333 	dev_put(dev);
3334 	return 0;
3335 }
3336 
3337 /**
3338  *	unregister_netdev - remove device from the kernel
3339  *	@dev: device
3340  *
3341  *	This function shuts down a device interface and removes it
3342  *	from the kernel tables. On success 0 is returned, on a failure
3343  *	a negative errno code is returned.
3344  *
3345  *	This is just a wrapper for unregister_netdevice that takes
3346  *	the rtnl semaphore.  In general you want to use this and not
3347  *	unregister_netdevice.
3348  */
3349 void unregister_netdev(struct net_device *dev)
3350 {
3351 	rtnl_lock();
3352 	unregister_netdevice(dev);
3353 	rtnl_unlock();
3354 }
3355 
3356 EXPORT_SYMBOL(unregister_netdev);
3357 
3358 #ifdef CONFIG_HOTPLUG_CPU
3359 static int dev_cpu_callback(struct notifier_block *nfb,
3360 			    unsigned long action,
3361 			    void *ocpu)
3362 {
3363 	struct sk_buff **list_skb;
3364 	struct net_device **list_net;
3365 	struct sk_buff *skb;
3366 	unsigned int cpu, oldcpu = (unsigned long)ocpu;
3367 	struct softnet_data *sd, *oldsd;
3368 
3369 	if (action != CPU_DEAD)
3370 		return NOTIFY_OK;
3371 
3372 	local_irq_disable();
3373 	cpu = smp_processor_id();
3374 	sd = &per_cpu(softnet_data, cpu);
3375 	oldsd = &per_cpu(softnet_data, oldcpu);
3376 
3377 	/* Find end of our completion_queue. */
3378 	list_skb = &sd->completion_queue;
3379 	while (*list_skb)
3380 		list_skb = &(*list_skb)->next;
3381 	/* Append completion queue from offline CPU. */
3382 	*list_skb = oldsd->completion_queue;
3383 	oldsd->completion_queue = NULL;
3384 
3385 	/* Find end of our output_queue. */
3386 	list_net = &sd->output_queue;
3387 	while (*list_net)
3388 		list_net = &(*list_net)->next_sched;
3389 	/* Append output queue from offline CPU. */
3390 	*list_net = oldsd->output_queue;
3391 	oldsd->output_queue = NULL;
3392 
3393 	raise_softirq_irqoff(NET_TX_SOFTIRQ);
3394 	local_irq_enable();
3395 
3396 	/* Process offline CPU's input_pkt_queue */
3397 	while ((skb = __skb_dequeue(&oldsd->input_pkt_queue)))
3398 		netif_rx(skb);
3399 
3400 	return NOTIFY_OK;
3401 }
3402 #endif /* CONFIG_HOTPLUG_CPU */
3403 
3404 #ifdef CONFIG_NET_DMA
3405 /**
3406  * net_dma_rebalance -
3407  * This is called when the number of channels allocated to the net_dma_client
3408  * changes.  The net_dma_client tries to have one DMA channel per CPU.
3409  */
3410 static void net_dma_rebalance(void)
3411 {
3412 	unsigned int cpu, i, n;
3413 	struct dma_chan *chan;
3414 
3415 	if (net_dma_count == 0) {
3416 		for_each_online_cpu(cpu)
3417 			rcu_assign_pointer(per_cpu(softnet_data, cpu).net_dma, NULL);
3418 		return;
3419 	}
3420 
3421 	i = 0;
3422 	cpu = first_cpu(cpu_online_map);
3423 
3424 	rcu_read_lock();
3425 	list_for_each_entry(chan, &net_dma_client->channels, client_node) {
3426 		n = ((num_online_cpus() / net_dma_count)
3427 		   + (i < (num_online_cpus() % net_dma_count) ? 1 : 0));
3428 
3429 		while(n) {
3430 			per_cpu(softnet_data, cpu).net_dma = chan;
3431 			cpu = next_cpu(cpu, cpu_online_map);
3432 			n--;
3433 		}
3434 		i++;
3435 	}
3436 	rcu_read_unlock();
3437 }
3438 
3439 /**
3440  * netdev_dma_event - event callback for the net_dma_client
3441  * @client: should always be net_dma_client
3442  * @chan: DMA channel for the event
3443  * @event: event type
3444  */
3445 static void netdev_dma_event(struct dma_client *client, struct dma_chan *chan,
3446 	enum dma_event event)
3447 {
3448 	spin_lock(&net_dma_event_lock);
3449 	switch (event) {
3450 	case DMA_RESOURCE_ADDED:
3451 		net_dma_count++;
3452 		net_dma_rebalance();
3453 		break;
3454 	case DMA_RESOURCE_REMOVED:
3455 		net_dma_count--;
3456 		net_dma_rebalance();
3457 		break;
3458 	default:
3459 		break;
3460 	}
3461 	spin_unlock(&net_dma_event_lock);
3462 }
3463 
3464 /**
3465  * netdev_dma_regiser - register the networking subsystem as a DMA client
3466  */
3467 static int __init netdev_dma_register(void)
3468 {
3469 	spin_lock_init(&net_dma_event_lock);
3470 	net_dma_client = dma_async_client_register(netdev_dma_event);
3471 	if (net_dma_client == NULL)
3472 		return -ENOMEM;
3473 
3474 	dma_async_client_chan_request(net_dma_client, num_online_cpus());
3475 	return 0;
3476 }
3477 
3478 #else
3479 static int __init netdev_dma_register(void) { return -ENODEV; }
3480 #endif /* CONFIG_NET_DMA */
3481 
3482 /*
3483  *	Initialize the DEV module. At boot time this walks the device list and
3484  *	unhooks any devices that fail to initialise (normally hardware not
3485  *	present) and leaves us with a valid list of present and active devices.
3486  *
3487  */
3488 
3489 /*
3490  *       This is called single threaded during boot, so no need
3491  *       to take the rtnl semaphore.
3492  */
3493 static int __init net_dev_init(void)
3494 {
3495 	int i, rc = -ENOMEM;
3496 
3497 	BUG_ON(!dev_boot_phase);
3498 
3499 	net_random_init();
3500 
3501 	if (dev_proc_init())
3502 		goto out;
3503 
3504 	if (netdev_sysfs_init())
3505 		goto out;
3506 
3507 	INIT_LIST_HEAD(&ptype_all);
3508 	for (i = 0; i < 16; i++)
3509 		INIT_LIST_HEAD(&ptype_base[i]);
3510 
3511 	for (i = 0; i < ARRAY_SIZE(dev_name_head); i++)
3512 		INIT_HLIST_HEAD(&dev_name_head[i]);
3513 
3514 	for (i = 0; i < ARRAY_SIZE(dev_index_head); i++)
3515 		INIT_HLIST_HEAD(&dev_index_head[i]);
3516 
3517 	/*
3518 	 *	Initialise the packet receive queues.
3519 	 */
3520 
3521 	for_each_possible_cpu(i) {
3522 		struct softnet_data *queue;
3523 
3524 		queue = &per_cpu(softnet_data, i);
3525 		skb_queue_head_init(&queue->input_pkt_queue);
3526 		queue->completion_queue = NULL;
3527 		INIT_LIST_HEAD(&queue->poll_list);
3528 		set_bit(__LINK_STATE_START, &queue->backlog_dev.state);
3529 		queue->backlog_dev.weight = weight_p;
3530 		queue->backlog_dev.poll = process_backlog;
3531 		atomic_set(&queue->backlog_dev.refcnt, 1);
3532 	}
3533 
3534 	netdev_dma_register();
3535 
3536 	dev_boot_phase = 0;
3537 
3538 	open_softirq(NET_TX_SOFTIRQ, net_tx_action, NULL);
3539 	open_softirq(NET_RX_SOFTIRQ, net_rx_action, NULL);
3540 
3541 	hotcpu_notifier(dev_cpu_callback, 0);
3542 	dst_init();
3543 	dev_mcast_init();
3544 	rc = 0;
3545 out:
3546 	return rc;
3547 }
3548 
3549 subsys_initcall(net_dev_init);
3550 
3551 EXPORT_SYMBOL(__dev_get_by_index);
3552 EXPORT_SYMBOL(__dev_get_by_name);
3553 EXPORT_SYMBOL(__dev_remove_pack);
3554 EXPORT_SYMBOL(dev_valid_name);
3555 EXPORT_SYMBOL(dev_add_pack);
3556 EXPORT_SYMBOL(dev_alloc_name);
3557 EXPORT_SYMBOL(dev_close);
3558 EXPORT_SYMBOL(dev_get_by_flags);
3559 EXPORT_SYMBOL(dev_get_by_index);
3560 EXPORT_SYMBOL(dev_get_by_name);
3561 EXPORT_SYMBOL(dev_open);
3562 EXPORT_SYMBOL(dev_queue_xmit);
3563 EXPORT_SYMBOL(dev_remove_pack);
3564 EXPORT_SYMBOL(dev_set_allmulti);
3565 EXPORT_SYMBOL(dev_set_promiscuity);
3566 EXPORT_SYMBOL(dev_change_flags);
3567 EXPORT_SYMBOL(dev_set_mtu);
3568 EXPORT_SYMBOL(dev_set_mac_address);
3569 EXPORT_SYMBOL(free_netdev);
3570 EXPORT_SYMBOL(netdev_boot_setup_check);
3571 EXPORT_SYMBOL(netdev_set_master);
3572 EXPORT_SYMBOL(netdev_state_change);
3573 EXPORT_SYMBOL(netif_receive_skb);
3574 EXPORT_SYMBOL(netif_rx);
3575 EXPORT_SYMBOL(register_gifconf);
3576 EXPORT_SYMBOL(register_netdevice);
3577 EXPORT_SYMBOL(register_netdevice_notifier);
3578 EXPORT_SYMBOL(skb_checksum_help);
3579 EXPORT_SYMBOL(synchronize_net);
3580 EXPORT_SYMBOL(unregister_netdevice);
3581 EXPORT_SYMBOL(unregister_netdevice_notifier);
3582 EXPORT_SYMBOL(net_enable_timestamp);
3583 EXPORT_SYMBOL(net_disable_timestamp);
3584 EXPORT_SYMBOL(dev_get_flags);
3585 
3586 #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
3587 EXPORT_SYMBOL(br_handle_frame_hook);
3588 EXPORT_SYMBOL(br_fdb_get_hook);
3589 EXPORT_SYMBOL(br_fdb_put_hook);
3590 #endif
3591 
3592 #ifdef CONFIG_KMOD
3593 EXPORT_SYMBOL(dev_load);
3594 #endif
3595 
3596 EXPORT_PER_CPU_SYMBOL(softnet_data);
3597