xref: /linux-6.15/include/linux/netdevice.h (revision 93707cba)
1 /*
2  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3  *		operating system.  INET is implemented using the  BSD Socket
4  *		interface as the means of communication with the user level.
5  *
6  *		Definitions for the Interfaces handler.
7  *
8  * Version:	@(#)dev.h	1.0.10	08/12/93
9  *
10  * Authors:	Ross Biro
11  *		Fred N. van Kempen, <[email protected]>
12  *		Corey Minyard <[email protected]>
13  *		Donald J. Becker, <[email protected]>
14  *		Alan Cox, <[email protected]>
15  *		Bjorn Ekwall. <[email protected]>
16  *              Pekka Riikonen <[email protected]>
17  *
18  *		This program is free software; you can redistribute it and/or
19  *		modify it under the terms of the GNU General Public License
20  *		as published by the Free Software Foundation; either version
21  *		2 of the License, or (at your option) any later version.
22  *
23  *		Moved to /usr/include/linux for NET3
24  */
25 #ifndef _LINUX_NETDEVICE_H
26 #define _LINUX_NETDEVICE_H
27 
28 #include <linux/timer.h>
29 #include <linux/bug.h>
30 #include <linux/delay.h>
31 #include <linux/atomic.h>
32 #include <linux/prefetch.h>
33 #include <asm/cache.h>
34 #include <asm/byteorder.h>
35 
36 #include <linux/percpu.h>
37 #include <linux/rculist.h>
38 #include <linux/workqueue.h>
39 #include <linux/dynamic_queue_limits.h>
40 
41 #include <linux/ethtool.h>
42 #include <net/net_namespace.h>
43 #ifdef CONFIG_DCB
44 #include <net/dcbnl.h>
45 #endif
46 #include <net/netprio_cgroup.h>
47 #include <net/xdp.h>
48 
49 #include <linux/netdev_features.h>
50 #include <linux/neighbour.h>
51 #include <uapi/linux/netdevice.h>
52 #include <uapi/linux/if_bonding.h>
53 #include <uapi/linux/pkt_cls.h>
54 #include <linux/hashtable.h>
55 
56 struct netpoll_info;
57 struct device;
58 struct phy_device;
59 struct dsa_port;
60 
61 /* 802.11 specific */
62 struct wireless_dev;
63 /* 802.15.4 specific */
64 struct wpan_dev;
65 struct mpls_dev;
66 /* UDP Tunnel offloads */
67 struct udp_tunnel_info;
68 struct bpf_prog;
69 struct xdp_buff;
70 
71 void netdev_set_default_ethtool_ops(struct net_device *dev,
72 				    const struct ethtool_ops *ops);
73 
74 /* Backlog congestion levels */
75 #define NET_RX_SUCCESS		0	/* keep 'em coming, baby */
76 #define NET_RX_DROP		1	/* packet dropped */
77 
78 /*
79  * Transmit return codes: transmit return codes originate from three different
80  * namespaces:
81  *
82  * - qdisc return codes
83  * - driver transmit return codes
84  * - errno values
85  *
86  * Drivers are allowed to return any one of those in their hard_start_xmit()
87  * function. Real network devices commonly used with qdiscs should only return
88  * the driver transmit return codes though - when qdiscs are used, the actual
89  * transmission happens asynchronously, so the value is not propagated to
90  * higher layers. Virtual network devices transmit synchronously; in this case
91  * the driver transmit return codes are consumed by dev_queue_xmit(), and all
92  * others are propagated to higher layers.
93  */
94 
95 /* qdisc ->enqueue() return codes. */
96 #define NET_XMIT_SUCCESS	0x00
97 #define NET_XMIT_DROP		0x01	/* skb dropped			*/
98 #define NET_XMIT_CN		0x02	/* congestion notification	*/
99 #define NET_XMIT_MASK		0x0f	/* qdisc flags in net/sch_generic.h */
100 
101 /* NET_XMIT_CN is special. It does not guarantee that this packet is lost. It
102  * indicates that the device will soon be dropping packets, or already drops
103  * some packets of the same priority; prompting us to send less aggressively. */
104 #define net_xmit_eval(e)	((e) == NET_XMIT_CN ? 0 : (e))
105 #define net_xmit_errno(e)	((e) != NET_XMIT_CN ? -ENOBUFS : 0)
106 
107 /* Driver transmit return codes */
108 #define NETDEV_TX_MASK		0xf0
109 
110 enum netdev_tx {
111 	__NETDEV_TX_MIN	 = INT_MIN,	/* make sure enum is signed */
112 	NETDEV_TX_OK	 = 0x00,	/* driver took care of packet */
113 	NETDEV_TX_BUSY	 = 0x10,	/* driver tx path was busy*/
114 };
115 typedef enum netdev_tx netdev_tx_t;
116 
117 /*
118  * Current order: NETDEV_TX_MASK > NET_XMIT_MASK >= 0 is significant;
119  * hard_start_xmit() return < NET_XMIT_MASK means skb was consumed.
120  */
121 static inline bool dev_xmit_complete(int rc)
122 {
123 	/*
124 	 * Positive cases with an skb consumed by a driver:
125 	 * - successful transmission (rc == NETDEV_TX_OK)
126 	 * - error while transmitting (rc < 0)
127 	 * - error while queueing to a different device (rc & NET_XMIT_MASK)
128 	 */
129 	if (likely(rc < NET_XMIT_MASK))
130 		return true;
131 
132 	return false;
133 }
134 
135 /*
136  *	Compute the worst-case header length according to the protocols
137  *	used.
138  */
139 
140 #if defined(CONFIG_HYPERV_NET)
141 # define LL_MAX_HEADER 128
142 #elif defined(CONFIG_WLAN) || IS_ENABLED(CONFIG_AX25)
143 # if defined(CONFIG_MAC80211_MESH)
144 #  define LL_MAX_HEADER 128
145 # else
146 #  define LL_MAX_HEADER 96
147 # endif
148 #else
149 # define LL_MAX_HEADER 32
150 #endif
151 
152 #if !IS_ENABLED(CONFIG_NET_IPIP) && !IS_ENABLED(CONFIG_NET_IPGRE) && \
153     !IS_ENABLED(CONFIG_IPV6_SIT) && !IS_ENABLED(CONFIG_IPV6_TUNNEL)
154 #define MAX_HEADER LL_MAX_HEADER
155 #else
156 #define MAX_HEADER (LL_MAX_HEADER + 48)
157 #endif
158 
159 /*
160  *	Old network device statistics. Fields are native words
161  *	(unsigned long) so they can be read and written atomically.
162  */
163 
164 struct net_device_stats {
165 	unsigned long	rx_packets;
166 	unsigned long	tx_packets;
167 	unsigned long	rx_bytes;
168 	unsigned long	tx_bytes;
169 	unsigned long	rx_errors;
170 	unsigned long	tx_errors;
171 	unsigned long	rx_dropped;
172 	unsigned long	tx_dropped;
173 	unsigned long	multicast;
174 	unsigned long	collisions;
175 	unsigned long	rx_length_errors;
176 	unsigned long	rx_over_errors;
177 	unsigned long	rx_crc_errors;
178 	unsigned long	rx_frame_errors;
179 	unsigned long	rx_fifo_errors;
180 	unsigned long	rx_missed_errors;
181 	unsigned long	tx_aborted_errors;
182 	unsigned long	tx_carrier_errors;
183 	unsigned long	tx_fifo_errors;
184 	unsigned long	tx_heartbeat_errors;
185 	unsigned long	tx_window_errors;
186 	unsigned long	rx_compressed;
187 	unsigned long	tx_compressed;
188 };
189 
190 
191 #include <linux/cache.h>
192 #include <linux/skbuff.h>
193 
194 #ifdef CONFIG_RPS
195 #include <linux/static_key.h>
196 extern struct static_key rps_needed;
197 extern struct static_key rfs_needed;
198 #endif
199 
200 struct neighbour;
201 struct neigh_parms;
202 struct sk_buff;
203 
204 struct netdev_hw_addr {
205 	struct list_head	list;
206 	unsigned char		addr[MAX_ADDR_LEN];
207 	unsigned char		type;
208 #define NETDEV_HW_ADDR_T_LAN		1
209 #define NETDEV_HW_ADDR_T_SAN		2
210 #define NETDEV_HW_ADDR_T_SLAVE		3
211 #define NETDEV_HW_ADDR_T_UNICAST	4
212 #define NETDEV_HW_ADDR_T_MULTICAST	5
213 	bool			global_use;
214 	int			sync_cnt;
215 	int			refcount;
216 	int			synced;
217 	struct rcu_head		rcu_head;
218 };
219 
220 struct netdev_hw_addr_list {
221 	struct list_head	list;
222 	int			count;
223 };
224 
225 #define netdev_hw_addr_list_count(l) ((l)->count)
226 #define netdev_hw_addr_list_empty(l) (netdev_hw_addr_list_count(l) == 0)
227 #define netdev_hw_addr_list_for_each(ha, l) \
228 	list_for_each_entry(ha, &(l)->list, list)
229 
230 #define netdev_uc_count(dev) netdev_hw_addr_list_count(&(dev)->uc)
231 #define netdev_uc_empty(dev) netdev_hw_addr_list_empty(&(dev)->uc)
232 #define netdev_for_each_uc_addr(ha, dev) \
233 	netdev_hw_addr_list_for_each(ha, &(dev)->uc)
234 
235 #define netdev_mc_count(dev) netdev_hw_addr_list_count(&(dev)->mc)
236 #define netdev_mc_empty(dev) netdev_hw_addr_list_empty(&(dev)->mc)
237 #define netdev_for_each_mc_addr(ha, dev) \
238 	netdev_hw_addr_list_for_each(ha, &(dev)->mc)
239 
240 struct hh_cache {
241 	unsigned int	hh_len;
242 	seqlock_t	hh_lock;
243 
244 	/* cached hardware header; allow for machine alignment needs.        */
245 #define HH_DATA_MOD	16
246 #define HH_DATA_OFF(__len) \
247 	(HH_DATA_MOD - (((__len - 1) & (HH_DATA_MOD - 1)) + 1))
248 #define HH_DATA_ALIGN(__len) \
249 	(((__len)+(HH_DATA_MOD-1))&~(HH_DATA_MOD - 1))
250 	unsigned long	hh_data[HH_DATA_ALIGN(LL_MAX_HEADER) / sizeof(long)];
251 };
252 
253 /* Reserve HH_DATA_MOD byte-aligned hard_header_len, but at least that much.
254  * Alternative is:
255  *   dev->hard_header_len ? (dev->hard_header_len +
256  *                           (HH_DATA_MOD - 1)) & ~(HH_DATA_MOD - 1) : 0
257  *
258  * We could use other alignment values, but we must maintain the
259  * relationship HH alignment <= LL alignment.
260  */
261 #define LL_RESERVED_SPACE(dev) \
262 	((((dev)->hard_header_len+(dev)->needed_headroom)&~(HH_DATA_MOD - 1)) + HH_DATA_MOD)
263 #define LL_RESERVED_SPACE_EXTRA(dev,extra) \
264 	((((dev)->hard_header_len+(dev)->needed_headroom+(extra))&~(HH_DATA_MOD - 1)) + HH_DATA_MOD)
265 
266 struct header_ops {
267 	int	(*create) (struct sk_buff *skb, struct net_device *dev,
268 			   unsigned short type, const void *daddr,
269 			   const void *saddr, unsigned int len);
270 	int	(*parse)(const struct sk_buff *skb, unsigned char *haddr);
271 	int	(*cache)(const struct neighbour *neigh, struct hh_cache *hh, __be16 type);
272 	void	(*cache_update)(struct hh_cache *hh,
273 				const struct net_device *dev,
274 				const unsigned char *haddr);
275 	bool	(*validate)(const char *ll_header, unsigned int len);
276 };
277 
278 /* These flag bits are private to the generic network queueing
279  * layer; they may not be explicitly referenced by any other
280  * code.
281  */
282 
283 enum netdev_state_t {
284 	__LINK_STATE_START,
285 	__LINK_STATE_PRESENT,
286 	__LINK_STATE_NOCARRIER,
287 	__LINK_STATE_LINKWATCH_PENDING,
288 	__LINK_STATE_DORMANT,
289 };
290 
291 
292 /*
293  * This structure holds boot-time configured netdevice settings. They
294  * are then used in the device probing.
295  */
296 struct netdev_boot_setup {
297 	char name[IFNAMSIZ];
298 	struct ifmap map;
299 };
300 #define NETDEV_BOOT_SETUP_MAX 8
301 
302 int __init netdev_boot_setup(char *str);
303 
304 /*
305  * Structure for NAPI scheduling similar to tasklet but with weighting
306  */
307 struct napi_struct {
308 	/* The poll_list must only be managed by the entity which
309 	 * changes the state of the NAPI_STATE_SCHED bit.  This means
310 	 * whoever atomically sets that bit can add this napi_struct
311 	 * to the per-CPU poll_list, and whoever clears that bit
312 	 * can remove from the list right before clearing the bit.
313 	 */
314 	struct list_head	poll_list;
315 
316 	unsigned long		state;
317 	int			weight;
318 	unsigned int		gro_count;
319 	int			(*poll)(struct napi_struct *, int);
320 #ifdef CONFIG_NETPOLL
321 	int			poll_owner;
322 #endif
323 	struct net_device	*dev;
324 	struct sk_buff		*gro_list;
325 	struct sk_buff		*skb;
326 	struct hrtimer		timer;
327 	struct list_head	dev_list;
328 	struct hlist_node	napi_hash_node;
329 	unsigned int		napi_id;
330 };
331 
332 enum {
333 	NAPI_STATE_SCHED,	/* Poll is scheduled */
334 	NAPI_STATE_MISSED,	/* reschedule a napi */
335 	NAPI_STATE_DISABLE,	/* Disable pending */
336 	NAPI_STATE_NPSVC,	/* Netpoll - don't dequeue from poll_list */
337 	NAPI_STATE_HASHED,	/* In NAPI hash (busy polling possible) */
338 	NAPI_STATE_NO_BUSY_POLL,/* Do not add in napi_hash, no busy polling */
339 	NAPI_STATE_IN_BUSY_POLL,/* sk_busy_loop() owns this NAPI */
340 };
341 
342 enum {
343 	NAPIF_STATE_SCHED	 = BIT(NAPI_STATE_SCHED),
344 	NAPIF_STATE_MISSED	 = BIT(NAPI_STATE_MISSED),
345 	NAPIF_STATE_DISABLE	 = BIT(NAPI_STATE_DISABLE),
346 	NAPIF_STATE_NPSVC	 = BIT(NAPI_STATE_NPSVC),
347 	NAPIF_STATE_HASHED	 = BIT(NAPI_STATE_HASHED),
348 	NAPIF_STATE_NO_BUSY_POLL = BIT(NAPI_STATE_NO_BUSY_POLL),
349 	NAPIF_STATE_IN_BUSY_POLL = BIT(NAPI_STATE_IN_BUSY_POLL),
350 };
351 
352 enum gro_result {
353 	GRO_MERGED,
354 	GRO_MERGED_FREE,
355 	GRO_HELD,
356 	GRO_NORMAL,
357 	GRO_DROP,
358 	GRO_CONSUMED,
359 };
360 typedef enum gro_result gro_result_t;
361 
362 /*
363  * enum rx_handler_result - Possible return values for rx_handlers.
364  * @RX_HANDLER_CONSUMED: skb was consumed by rx_handler, do not process it
365  * further.
366  * @RX_HANDLER_ANOTHER: Do another round in receive path. This is indicated in
367  * case skb->dev was changed by rx_handler.
368  * @RX_HANDLER_EXACT: Force exact delivery, no wildcard.
369  * @RX_HANDLER_PASS: Do nothing, pass the skb as if no rx_handler was called.
370  *
371  * rx_handlers are functions called from inside __netif_receive_skb(), to do
372  * special processing of the skb, prior to delivery to protocol handlers.
373  *
374  * Currently, a net_device can only have a single rx_handler registered. Trying
375  * to register a second rx_handler will return -EBUSY.
376  *
377  * To register a rx_handler on a net_device, use netdev_rx_handler_register().
378  * To unregister a rx_handler on a net_device, use
379  * netdev_rx_handler_unregister().
380  *
381  * Upon return, rx_handler is expected to tell __netif_receive_skb() what to
382  * do with the skb.
383  *
384  * If the rx_handler consumed the skb in some way, it should return
385  * RX_HANDLER_CONSUMED. This is appropriate when the rx_handler arranged for
386  * the skb to be delivered in some other way.
387  *
388  * If the rx_handler changed skb->dev, to divert the skb to another
389  * net_device, it should return RX_HANDLER_ANOTHER. The rx_handler for the
390  * new device will be called if it exists.
391  *
392  * If the rx_handler decides the skb should be ignored, it should return
393  * RX_HANDLER_EXACT. The skb will only be delivered to protocol handlers that
394  * are registered on exact device (ptype->dev == skb->dev).
395  *
396  * If the rx_handler didn't change skb->dev, but wants the skb to be normally
397  * delivered, it should return RX_HANDLER_PASS.
398  *
399  * A device without a registered rx_handler will behave as if rx_handler
400  * returned RX_HANDLER_PASS.
401  */
402 
403 enum rx_handler_result {
404 	RX_HANDLER_CONSUMED,
405 	RX_HANDLER_ANOTHER,
406 	RX_HANDLER_EXACT,
407 	RX_HANDLER_PASS,
408 };
409 typedef enum rx_handler_result rx_handler_result_t;
410 typedef rx_handler_result_t rx_handler_func_t(struct sk_buff **pskb);
411 
412 void __napi_schedule(struct napi_struct *n);
413 void __napi_schedule_irqoff(struct napi_struct *n);
414 
415 static inline bool napi_disable_pending(struct napi_struct *n)
416 {
417 	return test_bit(NAPI_STATE_DISABLE, &n->state);
418 }
419 
420 bool napi_schedule_prep(struct napi_struct *n);
421 
422 /**
423  *	napi_schedule - schedule NAPI poll
424  *	@n: NAPI context
425  *
426  * Schedule NAPI poll routine to be called if it is not already
427  * running.
428  */
429 static inline void napi_schedule(struct napi_struct *n)
430 {
431 	if (napi_schedule_prep(n))
432 		__napi_schedule(n);
433 }
434 
435 /**
436  *	napi_schedule_irqoff - schedule NAPI poll
437  *	@n: NAPI context
438  *
439  * Variant of napi_schedule(), assuming hard irqs are masked.
440  */
441 static inline void napi_schedule_irqoff(struct napi_struct *n)
442 {
443 	if (napi_schedule_prep(n))
444 		__napi_schedule_irqoff(n);
445 }
446 
447 /* Try to reschedule poll. Called by dev->poll() after napi_complete().  */
448 static inline bool napi_reschedule(struct napi_struct *napi)
449 {
450 	if (napi_schedule_prep(napi)) {
451 		__napi_schedule(napi);
452 		return true;
453 	}
454 	return false;
455 }
456 
457 bool napi_complete_done(struct napi_struct *n, int work_done);
458 /**
459  *	napi_complete - NAPI processing complete
460  *	@n: NAPI context
461  *
462  * Mark NAPI processing as complete.
463  * Consider using napi_complete_done() instead.
464  * Return false if device should avoid rearming interrupts.
465  */
466 static inline bool napi_complete(struct napi_struct *n)
467 {
468 	return napi_complete_done(n, 0);
469 }
470 
471 /**
472  *	napi_hash_del - remove a NAPI from global table
473  *	@napi: NAPI context
474  *
475  * Warning: caller must observe RCU grace period
476  * before freeing memory containing @napi, if
477  * this function returns true.
478  * Note: core networking stack automatically calls it
479  * from netif_napi_del().
480  * Drivers might want to call this helper to combine all
481  * the needed RCU grace periods into a single one.
482  */
483 bool napi_hash_del(struct napi_struct *napi);
484 
485 /**
486  *	napi_disable - prevent NAPI from scheduling
487  *	@n: NAPI context
488  *
489  * Stop NAPI from being scheduled on this context.
490  * Waits till any outstanding processing completes.
491  */
492 void napi_disable(struct napi_struct *n);
493 
494 /**
495  *	napi_enable - enable NAPI scheduling
496  *	@n: NAPI context
497  *
498  * Resume NAPI from being scheduled on this context.
499  * Must be paired with napi_disable.
500  */
501 static inline void napi_enable(struct napi_struct *n)
502 {
503 	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
504 	smp_mb__before_atomic();
505 	clear_bit(NAPI_STATE_SCHED, &n->state);
506 	clear_bit(NAPI_STATE_NPSVC, &n->state);
507 }
508 
509 /**
510  *	napi_synchronize - wait until NAPI is not running
511  *	@n: NAPI context
512  *
513  * Wait until NAPI is done being scheduled on this context.
514  * Waits till any outstanding processing completes but
515  * does not disable future activations.
516  */
517 static inline void napi_synchronize(const struct napi_struct *n)
518 {
519 	if (IS_ENABLED(CONFIG_SMP))
520 		while (test_bit(NAPI_STATE_SCHED, &n->state))
521 			msleep(1);
522 	else
523 		barrier();
524 }
525 
526 enum netdev_queue_state_t {
527 	__QUEUE_STATE_DRV_XOFF,
528 	__QUEUE_STATE_STACK_XOFF,
529 	__QUEUE_STATE_FROZEN,
530 };
531 
532 #define QUEUE_STATE_DRV_XOFF	(1 << __QUEUE_STATE_DRV_XOFF)
533 #define QUEUE_STATE_STACK_XOFF	(1 << __QUEUE_STATE_STACK_XOFF)
534 #define QUEUE_STATE_FROZEN	(1 << __QUEUE_STATE_FROZEN)
535 
536 #define QUEUE_STATE_ANY_XOFF	(QUEUE_STATE_DRV_XOFF | QUEUE_STATE_STACK_XOFF)
537 #define QUEUE_STATE_ANY_XOFF_OR_FROZEN (QUEUE_STATE_ANY_XOFF | \
538 					QUEUE_STATE_FROZEN)
539 #define QUEUE_STATE_DRV_XOFF_OR_FROZEN (QUEUE_STATE_DRV_XOFF | \
540 					QUEUE_STATE_FROZEN)
541 
542 /*
543  * __QUEUE_STATE_DRV_XOFF is used by drivers to stop the transmit queue.  The
544  * netif_tx_* functions below are used to manipulate this flag.  The
545  * __QUEUE_STATE_STACK_XOFF flag is used by the stack to stop the transmit
546  * queue independently.  The netif_xmit_*stopped functions below are called
547  * to check if the queue has been stopped by the driver or stack (either
548  * of the XOFF bits are set in the state).  Drivers should not need to call
549  * netif_xmit*stopped functions, they should only be using netif_tx_*.
550  */
551 
552 struct netdev_queue {
553 /*
554  * read-mostly part
555  */
556 	struct net_device	*dev;
557 	struct Qdisc __rcu	*qdisc;
558 	struct Qdisc		*qdisc_sleeping;
559 #ifdef CONFIG_SYSFS
560 	struct kobject		kobj;
561 #endif
562 #if defined(CONFIG_XPS) && defined(CONFIG_NUMA)
563 	int			numa_node;
564 #endif
565 	unsigned long		tx_maxrate;
566 	/*
567 	 * Number of TX timeouts for this queue
568 	 * (/sys/class/net/DEV/Q/trans_timeout)
569 	 */
570 	unsigned long		trans_timeout;
571 /*
572  * write-mostly part
573  */
574 	spinlock_t		_xmit_lock ____cacheline_aligned_in_smp;
575 	int			xmit_lock_owner;
576 	/*
577 	 * Time (in jiffies) of last Tx
578 	 */
579 	unsigned long		trans_start;
580 
581 	unsigned long		state;
582 
583 #ifdef CONFIG_BQL
584 	struct dql		dql;
585 #endif
586 } ____cacheline_aligned_in_smp;
587 
588 static inline int netdev_queue_numa_node_read(const struct netdev_queue *q)
589 {
590 #if defined(CONFIG_XPS) && defined(CONFIG_NUMA)
591 	return q->numa_node;
592 #else
593 	return NUMA_NO_NODE;
594 #endif
595 }
596 
597 static inline void netdev_queue_numa_node_write(struct netdev_queue *q, int node)
598 {
599 #if defined(CONFIG_XPS) && defined(CONFIG_NUMA)
600 	q->numa_node = node;
601 #endif
602 }
603 
604 #ifdef CONFIG_RPS
605 /*
606  * This structure holds an RPS map which can be of variable length.  The
607  * map is an array of CPUs.
608  */
609 struct rps_map {
610 	unsigned int len;
611 	struct rcu_head rcu;
612 	u16 cpus[0];
613 };
614 #define RPS_MAP_SIZE(_num) (sizeof(struct rps_map) + ((_num) * sizeof(u16)))
615 
616 /*
617  * The rps_dev_flow structure contains the mapping of a flow to a CPU, the
618  * tail pointer for that CPU's input queue at the time of last enqueue, and
619  * a hardware filter index.
620  */
621 struct rps_dev_flow {
622 	u16 cpu;
623 	u16 filter;
624 	unsigned int last_qtail;
625 };
626 #define RPS_NO_FILTER 0xffff
627 
628 /*
629  * The rps_dev_flow_table structure contains a table of flow mappings.
630  */
631 struct rps_dev_flow_table {
632 	unsigned int mask;
633 	struct rcu_head rcu;
634 	struct rps_dev_flow flows[0];
635 };
636 #define RPS_DEV_FLOW_TABLE_SIZE(_num) (sizeof(struct rps_dev_flow_table) + \
637     ((_num) * sizeof(struct rps_dev_flow)))
638 
639 /*
640  * The rps_sock_flow_table contains mappings of flows to the last CPU
641  * on which they were processed by the application (set in recvmsg).
642  * Each entry is a 32bit value. Upper part is the high-order bits
643  * of flow hash, lower part is CPU number.
644  * rps_cpu_mask is used to partition the space, depending on number of
645  * possible CPUs : rps_cpu_mask = roundup_pow_of_two(nr_cpu_ids) - 1
646  * For example, if 64 CPUs are possible, rps_cpu_mask = 0x3f,
647  * meaning we use 32-6=26 bits for the hash.
648  */
649 struct rps_sock_flow_table {
650 	u32	mask;
651 
652 	u32	ents[0] ____cacheline_aligned_in_smp;
653 };
654 #define	RPS_SOCK_FLOW_TABLE_SIZE(_num) (offsetof(struct rps_sock_flow_table, ents[_num]))
655 
656 #define RPS_NO_CPU 0xffff
657 
658 extern u32 rps_cpu_mask;
659 extern struct rps_sock_flow_table __rcu *rps_sock_flow_table;
660 
661 static inline void rps_record_sock_flow(struct rps_sock_flow_table *table,
662 					u32 hash)
663 {
664 	if (table && hash) {
665 		unsigned int index = hash & table->mask;
666 		u32 val = hash & ~rps_cpu_mask;
667 
668 		/* We only give a hint, preemption can change CPU under us */
669 		val |= raw_smp_processor_id();
670 
671 		if (table->ents[index] != val)
672 			table->ents[index] = val;
673 	}
674 }
675 
676 #ifdef CONFIG_RFS_ACCEL
677 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, u32 flow_id,
678 			 u16 filter_id);
679 #endif
680 #endif /* CONFIG_RPS */
681 
682 /* This structure contains an instance of an RX queue. */
683 struct netdev_rx_queue {
684 #ifdef CONFIG_RPS
685 	struct rps_map __rcu		*rps_map;
686 	struct rps_dev_flow_table __rcu	*rps_flow_table;
687 #endif
688 	struct kobject			kobj;
689 	struct net_device		*dev;
690 	struct xdp_rxq_info		xdp_rxq;
691 } ____cacheline_aligned_in_smp;
692 
693 /*
694  * RX queue sysfs structures and functions.
695  */
696 struct rx_queue_attribute {
697 	struct attribute attr;
698 	ssize_t (*show)(struct netdev_rx_queue *queue, char *buf);
699 	ssize_t (*store)(struct netdev_rx_queue *queue,
700 			 const char *buf, size_t len);
701 };
702 
703 #ifdef CONFIG_XPS
704 /*
705  * This structure holds an XPS map which can be of variable length.  The
706  * map is an array of queues.
707  */
708 struct xps_map {
709 	unsigned int len;
710 	unsigned int alloc_len;
711 	struct rcu_head rcu;
712 	u16 queues[0];
713 };
714 #define XPS_MAP_SIZE(_num) (sizeof(struct xps_map) + ((_num) * sizeof(u16)))
715 #define XPS_MIN_MAP_ALLOC ((L1_CACHE_ALIGN(offsetof(struct xps_map, queues[1])) \
716        - sizeof(struct xps_map)) / sizeof(u16))
717 
718 /*
719  * This structure holds all XPS maps for device.  Maps are indexed by CPU.
720  */
721 struct xps_dev_maps {
722 	struct rcu_head rcu;
723 	struct xps_map __rcu *cpu_map[0];
724 };
725 #define XPS_DEV_MAPS_SIZE(_tcs) (sizeof(struct xps_dev_maps) +		\
726 	(nr_cpu_ids * (_tcs) * sizeof(struct xps_map *)))
727 #endif /* CONFIG_XPS */
728 
729 #define TC_MAX_QUEUE	16
730 #define TC_BITMASK	15
731 /* HW offloaded queuing disciplines txq count and offset maps */
732 struct netdev_tc_txq {
733 	u16 count;
734 	u16 offset;
735 };
736 
737 #if defined(CONFIG_FCOE) || defined(CONFIG_FCOE_MODULE)
738 /*
739  * This structure is to hold information about the device
740  * configured to run FCoE protocol stack.
741  */
742 struct netdev_fcoe_hbainfo {
743 	char	manufacturer[64];
744 	char	serial_number[64];
745 	char	hardware_version[64];
746 	char	driver_version[64];
747 	char	optionrom_version[64];
748 	char	firmware_version[64];
749 	char	model[256];
750 	char	model_description[256];
751 };
752 #endif
753 
754 #define MAX_PHYS_ITEM_ID_LEN 32
755 
756 /* This structure holds a unique identifier to identify some
757  * physical item (port for example) used by a netdevice.
758  */
759 struct netdev_phys_item_id {
760 	unsigned char id[MAX_PHYS_ITEM_ID_LEN];
761 	unsigned char id_len;
762 };
763 
764 static inline bool netdev_phys_item_id_same(struct netdev_phys_item_id *a,
765 					    struct netdev_phys_item_id *b)
766 {
767 	return a->id_len == b->id_len &&
768 	       memcmp(a->id, b->id, a->id_len) == 0;
769 }
770 
771 typedef u16 (*select_queue_fallback_t)(struct net_device *dev,
772 				       struct sk_buff *skb);
773 
774 enum tc_setup_type {
775 	TC_SETUP_QDISC_MQPRIO,
776 	TC_SETUP_CLSU32,
777 	TC_SETUP_CLSFLOWER,
778 	TC_SETUP_CLSMATCHALL,
779 	TC_SETUP_CLSBPF,
780 	TC_SETUP_BLOCK,
781 	TC_SETUP_QDISC_CBS,
782 	TC_SETUP_QDISC_RED,
783 	TC_SETUP_QDISC_PRIO,
784 };
785 
786 /* These structures hold the attributes of bpf state that are being passed
787  * to the netdevice through the bpf op.
788  */
789 enum bpf_netdev_command {
790 	/* Set or clear a bpf program used in the earliest stages of packet
791 	 * rx. The prog will have been loaded as BPF_PROG_TYPE_XDP. The callee
792 	 * is responsible for calling bpf_prog_put on any old progs that are
793 	 * stored. In case of error, the callee need not release the new prog
794 	 * reference, but on success it takes ownership and must bpf_prog_put
795 	 * when it is no longer used.
796 	 */
797 	XDP_SETUP_PROG,
798 	XDP_SETUP_PROG_HW,
799 	/* Check if a bpf program is set on the device.  The callee should
800 	 * set @prog_attached to one of XDP_ATTACHED_* values, note that "true"
801 	 * is equivalent to XDP_ATTACHED_DRV.
802 	 */
803 	XDP_QUERY_PROG,
804 	/* BPF program for offload callbacks, invoked at program load time. */
805 	BPF_OFFLOAD_VERIFIER_PREP,
806 	BPF_OFFLOAD_TRANSLATE,
807 	BPF_OFFLOAD_DESTROY,
808 	BPF_OFFLOAD_MAP_ALLOC,
809 	BPF_OFFLOAD_MAP_FREE,
810 };
811 
812 struct bpf_prog_offload_ops;
813 struct netlink_ext_ack;
814 
815 struct netdev_bpf {
816 	enum bpf_netdev_command command;
817 	union {
818 		/* XDP_SETUP_PROG */
819 		struct {
820 			u32 flags;
821 			struct bpf_prog *prog;
822 			struct netlink_ext_ack *extack;
823 		};
824 		/* XDP_QUERY_PROG */
825 		struct {
826 			u8 prog_attached;
827 			u32 prog_id;
828 			/* flags with which program was installed */
829 			u32 prog_flags;
830 		};
831 		/* BPF_OFFLOAD_VERIFIER_PREP */
832 		struct {
833 			struct bpf_prog *prog;
834 			const struct bpf_prog_offload_ops *ops; /* callee set */
835 		} verifier;
836 		/* BPF_OFFLOAD_TRANSLATE, BPF_OFFLOAD_DESTROY */
837 		struct {
838 			struct bpf_prog *prog;
839 		} offload;
840 		/* BPF_OFFLOAD_MAP_ALLOC, BPF_OFFLOAD_MAP_FREE */
841 		struct {
842 			struct bpf_offloaded_map *offmap;
843 		};
844 	};
845 };
846 
847 #ifdef CONFIG_XFRM_OFFLOAD
848 struct xfrmdev_ops {
849 	int	(*xdo_dev_state_add) (struct xfrm_state *x);
850 	void	(*xdo_dev_state_delete) (struct xfrm_state *x);
851 	void	(*xdo_dev_state_free) (struct xfrm_state *x);
852 	bool	(*xdo_dev_offload_ok) (struct sk_buff *skb,
853 				       struct xfrm_state *x);
854 	void	(*xdo_dev_state_advance_esn) (struct xfrm_state *x);
855 };
856 #endif
857 
858 struct dev_ifalias {
859 	struct rcu_head rcuhead;
860 	char ifalias[];
861 };
862 
863 /*
864  * This structure defines the management hooks for network devices.
865  * The following hooks can be defined; unless noted otherwise, they are
866  * optional and can be filled with a null pointer.
867  *
868  * int (*ndo_init)(struct net_device *dev);
869  *     This function is called once when a network device is registered.
870  *     The network device can use this for any late stage initialization
871  *     or semantic validation. It can fail with an error code which will
872  *     be propagated back to register_netdev.
873  *
874  * void (*ndo_uninit)(struct net_device *dev);
875  *     This function is called when device is unregistered or when registration
876  *     fails. It is not called if init fails.
877  *
878  * int (*ndo_open)(struct net_device *dev);
879  *     This function is called when a network device transitions to the up
880  *     state.
881  *
882  * int (*ndo_stop)(struct net_device *dev);
883  *     This function is called when a network device transitions to the down
884  *     state.
885  *
886  * netdev_tx_t (*ndo_start_xmit)(struct sk_buff *skb,
887  *                               struct net_device *dev);
888  *	Called when a packet needs to be transmitted.
889  *	Returns NETDEV_TX_OK.  Can return NETDEV_TX_BUSY, but you should stop
890  *	the queue before that can happen; it's for obsolete devices and weird
891  *	corner cases, but the stack really does a non-trivial amount
892  *	of useless work if you return NETDEV_TX_BUSY.
893  *	Required; cannot be NULL.
894  *
895  * netdev_features_t (*ndo_features_check)(struct sk_buff *skb,
896  *					   struct net_device *dev
897  *					   netdev_features_t features);
898  *	Called by core transmit path to determine if device is capable of
899  *	performing offload operations on a given packet. This is to give
900  *	the device an opportunity to implement any restrictions that cannot
901  *	be otherwise expressed by feature flags. The check is called with
902  *	the set of features that the stack has calculated and it returns
903  *	those the driver believes to be appropriate.
904  *
905  * u16 (*ndo_select_queue)(struct net_device *dev, struct sk_buff *skb,
906  *                         void *accel_priv, select_queue_fallback_t fallback);
907  *	Called to decide which queue to use when device supports multiple
908  *	transmit queues.
909  *
910  * void (*ndo_change_rx_flags)(struct net_device *dev, int flags);
911  *	This function is called to allow device receiver to make
912  *	changes to configuration when multicast or promiscuous is enabled.
913  *
914  * void (*ndo_set_rx_mode)(struct net_device *dev);
915  *	This function is called device changes address list filtering.
916  *	If driver handles unicast address filtering, it should set
917  *	IFF_UNICAST_FLT in its priv_flags.
918  *
919  * int (*ndo_set_mac_address)(struct net_device *dev, void *addr);
920  *	This function  is called when the Media Access Control address
921  *	needs to be changed. If this interface is not defined, the
922  *	MAC address can not be changed.
923  *
924  * int (*ndo_validate_addr)(struct net_device *dev);
925  *	Test if Media Access Control address is valid for the device.
926  *
927  * int (*ndo_do_ioctl)(struct net_device *dev, struct ifreq *ifr, int cmd);
928  *	Called when a user requests an ioctl which can't be handled by
929  *	the generic interface code. If not defined ioctls return
930  *	not supported error code.
931  *
932  * int (*ndo_set_config)(struct net_device *dev, struct ifmap *map);
933  *	Used to set network devices bus interface parameters. This interface
934  *	is retained for legacy reasons; new devices should use the bus
935  *	interface (PCI) for low level management.
936  *
937  * int (*ndo_change_mtu)(struct net_device *dev, int new_mtu);
938  *	Called when a user wants to change the Maximum Transfer Unit
939  *	of a device.
940  *
941  * void (*ndo_tx_timeout)(struct net_device *dev);
942  *	Callback used when the transmitter has not made any progress
943  *	for dev->watchdog ticks.
944  *
945  * void (*ndo_get_stats64)(struct net_device *dev,
946  *                         struct rtnl_link_stats64 *storage);
947  * struct net_device_stats* (*ndo_get_stats)(struct net_device *dev);
948  *	Called when a user wants to get the network device usage
949  *	statistics. Drivers must do one of the following:
950  *	1. Define @ndo_get_stats64 to fill in a zero-initialised
951  *	   rtnl_link_stats64 structure passed by the caller.
952  *	2. Define @ndo_get_stats to update a net_device_stats structure
953  *	   (which should normally be dev->stats) and return a pointer to
954  *	   it. The structure may be changed asynchronously only if each
955  *	   field is written atomically.
956  *	3. Update dev->stats asynchronously and atomically, and define
957  *	   neither operation.
958  *
959  * bool (*ndo_has_offload_stats)(const struct net_device *dev, int attr_id)
960  *	Return true if this device supports offload stats of this attr_id.
961  *
962  * int (*ndo_get_offload_stats)(int attr_id, const struct net_device *dev,
963  *	void *attr_data)
964  *	Get statistics for offload operations by attr_id. Write it into the
965  *	attr_data pointer.
966  *
967  * int (*ndo_vlan_rx_add_vid)(struct net_device *dev, __be16 proto, u16 vid);
968  *	If device supports VLAN filtering this function is called when a
969  *	VLAN id is registered.
970  *
971  * int (*ndo_vlan_rx_kill_vid)(struct net_device *dev, __be16 proto, u16 vid);
972  *	If device supports VLAN filtering this function is called when a
973  *	VLAN id is unregistered.
974  *
975  * void (*ndo_poll_controller)(struct net_device *dev);
976  *
977  *	SR-IOV management functions.
978  * int (*ndo_set_vf_mac)(struct net_device *dev, int vf, u8* mac);
979  * int (*ndo_set_vf_vlan)(struct net_device *dev, int vf, u16 vlan,
980  *			  u8 qos, __be16 proto);
981  * int (*ndo_set_vf_rate)(struct net_device *dev, int vf, int min_tx_rate,
982  *			  int max_tx_rate);
983  * int (*ndo_set_vf_spoofchk)(struct net_device *dev, int vf, bool setting);
984  * int (*ndo_set_vf_trust)(struct net_device *dev, int vf, bool setting);
985  * int (*ndo_get_vf_config)(struct net_device *dev,
986  *			    int vf, struct ifla_vf_info *ivf);
987  * int (*ndo_set_vf_link_state)(struct net_device *dev, int vf, int link_state);
988  * int (*ndo_set_vf_port)(struct net_device *dev, int vf,
989  *			  struct nlattr *port[]);
990  *
991  *      Enable or disable the VF ability to query its RSS Redirection Table and
992  *      Hash Key. This is needed since on some devices VF share this information
993  *      with PF and querying it may introduce a theoretical security risk.
994  * int (*ndo_set_vf_rss_query_en)(struct net_device *dev, int vf, bool setting);
995  * int (*ndo_get_vf_port)(struct net_device *dev, int vf, struct sk_buff *skb);
996  * int (*ndo_setup_tc)(struct net_device *dev, enum tc_setup_type type,
997  *		       void *type_data);
998  *	Called to setup any 'tc' scheduler, classifier or action on @dev.
999  *	This is always called from the stack with the rtnl lock held and netif
1000  *	tx queues stopped. This allows the netdevice to perform queue
1001  *	management safely.
1002  *
1003  *	Fiber Channel over Ethernet (FCoE) offload functions.
1004  * int (*ndo_fcoe_enable)(struct net_device *dev);
1005  *	Called when the FCoE protocol stack wants to start using LLD for FCoE
1006  *	so the underlying device can perform whatever needed configuration or
1007  *	initialization to support acceleration of FCoE traffic.
1008  *
1009  * int (*ndo_fcoe_disable)(struct net_device *dev);
1010  *	Called when the FCoE protocol stack wants to stop using LLD for FCoE
1011  *	so the underlying device can perform whatever needed clean-ups to
1012  *	stop supporting acceleration of FCoE traffic.
1013  *
1014  * int (*ndo_fcoe_ddp_setup)(struct net_device *dev, u16 xid,
1015  *			     struct scatterlist *sgl, unsigned int sgc);
1016  *	Called when the FCoE Initiator wants to initialize an I/O that
1017  *	is a possible candidate for Direct Data Placement (DDP). The LLD can
1018  *	perform necessary setup and returns 1 to indicate the device is set up
1019  *	successfully to perform DDP on this I/O, otherwise this returns 0.
1020  *
1021  * int (*ndo_fcoe_ddp_done)(struct net_device *dev,  u16 xid);
1022  *	Called when the FCoE Initiator/Target is done with the DDPed I/O as
1023  *	indicated by the FC exchange id 'xid', so the underlying device can
1024  *	clean up and reuse resources for later DDP requests.
1025  *
1026  * int (*ndo_fcoe_ddp_target)(struct net_device *dev, u16 xid,
1027  *			      struct scatterlist *sgl, unsigned int sgc);
1028  *	Called when the FCoE Target wants to initialize an I/O that
1029  *	is a possible candidate for Direct Data Placement (DDP). The LLD can
1030  *	perform necessary setup and returns 1 to indicate the device is set up
1031  *	successfully to perform DDP on this I/O, otherwise this returns 0.
1032  *
1033  * int (*ndo_fcoe_get_hbainfo)(struct net_device *dev,
1034  *			       struct netdev_fcoe_hbainfo *hbainfo);
1035  *	Called when the FCoE Protocol stack wants information on the underlying
1036  *	device. This information is utilized by the FCoE protocol stack to
1037  *	register attributes with Fiber Channel management service as per the
1038  *	FC-GS Fabric Device Management Information(FDMI) specification.
1039  *
1040  * int (*ndo_fcoe_get_wwn)(struct net_device *dev, u64 *wwn, int type);
1041  *	Called when the underlying device wants to override default World Wide
1042  *	Name (WWN) generation mechanism in FCoE protocol stack to pass its own
1043  *	World Wide Port Name (WWPN) or World Wide Node Name (WWNN) to the FCoE
1044  *	protocol stack to use.
1045  *
1046  *	RFS acceleration.
1047  * int (*ndo_rx_flow_steer)(struct net_device *dev, const struct sk_buff *skb,
1048  *			    u16 rxq_index, u32 flow_id);
1049  *	Set hardware filter for RFS.  rxq_index is the target queue index;
1050  *	flow_id is a flow ID to be passed to rps_may_expire_flow() later.
1051  *	Return the filter ID on success, or a negative error code.
1052  *
1053  *	Slave management functions (for bridge, bonding, etc).
1054  * int (*ndo_add_slave)(struct net_device *dev, struct net_device *slave_dev);
1055  *	Called to make another netdev an underling.
1056  *
1057  * int (*ndo_del_slave)(struct net_device *dev, struct net_device *slave_dev);
1058  *	Called to release previously enslaved netdev.
1059  *
1060  *      Feature/offload setting functions.
1061  * netdev_features_t (*ndo_fix_features)(struct net_device *dev,
1062  *		netdev_features_t features);
1063  *	Adjusts the requested feature flags according to device-specific
1064  *	constraints, and returns the resulting flags. Must not modify
1065  *	the device state.
1066  *
1067  * int (*ndo_set_features)(struct net_device *dev, netdev_features_t features);
1068  *	Called to update device configuration to new features. Passed
1069  *	feature set might be less than what was returned by ndo_fix_features()).
1070  *	Must return >0 or -errno if it changed dev->features itself.
1071  *
1072  * int (*ndo_fdb_add)(struct ndmsg *ndm, struct nlattr *tb[],
1073  *		      struct net_device *dev,
1074  *		      const unsigned char *addr, u16 vid, u16 flags)
1075  *	Adds an FDB entry to dev for addr.
1076  * int (*ndo_fdb_del)(struct ndmsg *ndm, struct nlattr *tb[],
1077  *		      struct net_device *dev,
1078  *		      const unsigned char *addr, u16 vid)
1079  *	Deletes the FDB entry from dev coresponding to addr.
1080  * int (*ndo_fdb_dump)(struct sk_buff *skb, struct netlink_callback *cb,
1081  *		       struct net_device *dev, struct net_device *filter_dev,
1082  *		       int *idx)
1083  *	Used to add FDB entries to dump requests. Implementers should add
1084  *	entries to skb and update idx with the number of entries.
1085  *
1086  * int (*ndo_bridge_setlink)(struct net_device *dev, struct nlmsghdr *nlh,
1087  *			     u16 flags)
1088  * int (*ndo_bridge_getlink)(struct sk_buff *skb, u32 pid, u32 seq,
1089  *			     struct net_device *dev, u32 filter_mask,
1090  *			     int nlflags)
1091  * int (*ndo_bridge_dellink)(struct net_device *dev, struct nlmsghdr *nlh,
1092  *			     u16 flags);
1093  *
1094  * int (*ndo_change_carrier)(struct net_device *dev, bool new_carrier);
1095  *	Called to change device carrier. Soft-devices (like dummy, team, etc)
1096  *	which do not represent real hardware may define this to allow their
1097  *	userspace components to manage their virtual carrier state. Devices
1098  *	that determine carrier state from physical hardware properties (eg
1099  *	network cables) or protocol-dependent mechanisms (eg
1100  *	USB_CDC_NOTIFY_NETWORK_CONNECTION) should NOT implement this function.
1101  *
1102  * int (*ndo_get_phys_port_id)(struct net_device *dev,
1103  *			       struct netdev_phys_item_id *ppid);
1104  *	Called to get ID of physical port of this device. If driver does
1105  *	not implement this, it is assumed that the hw is not able to have
1106  *	multiple net devices on single physical port.
1107  *
1108  * void (*ndo_udp_tunnel_add)(struct net_device *dev,
1109  *			      struct udp_tunnel_info *ti);
1110  *	Called by UDP tunnel to notify a driver about the UDP port and socket
1111  *	address family that a UDP tunnel is listnening to. It is called only
1112  *	when a new port starts listening. The operation is protected by the
1113  *	RTNL.
1114  *
1115  * void (*ndo_udp_tunnel_del)(struct net_device *dev,
1116  *			      struct udp_tunnel_info *ti);
1117  *	Called by UDP tunnel to notify the driver about a UDP port and socket
1118  *	address family that the UDP tunnel is not listening to anymore. The
1119  *	operation is protected by the RTNL.
1120  *
1121  * void* (*ndo_dfwd_add_station)(struct net_device *pdev,
1122  *				 struct net_device *dev)
1123  *	Called by upper layer devices to accelerate switching or other
1124  *	station functionality into hardware. 'pdev is the lowerdev
1125  *	to use for the offload and 'dev' is the net device that will
1126  *	back the offload. Returns a pointer to the private structure
1127  *	the upper layer will maintain.
1128  * void (*ndo_dfwd_del_station)(struct net_device *pdev, void *priv)
1129  *	Called by upper layer device to delete the station created
1130  *	by 'ndo_dfwd_add_station'. 'pdev' is the net device backing
1131  *	the station and priv is the structure returned by the add
1132  *	operation.
1133  * int (*ndo_set_tx_maxrate)(struct net_device *dev,
1134  *			     int queue_index, u32 maxrate);
1135  *	Called when a user wants to set a max-rate limitation of specific
1136  *	TX queue.
1137  * int (*ndo_get_iflink)(const struct net_device *dev);
1138  *	Called to get the iflink value of this device.
1139  * void (*ndo_change_proto_down)(struct net_device *dev,
1140  *				 bool proto_down);
1141  *	This function is used to pass protocol port error state information
1142  *	to the switch driver. The switch driver can react to the proto_down
1143  *      by doing a phys down on the associated switch port.
1144  * int (*ndo_fill_metadata_dst)(struct net_device *dev, struct sk_buff *skb);
1145  *	This function is used to get egress tunnel information for given skb.
1146  *	This is useful for retrieving outer tunnel header parameters while
1147  *	sampling packet.
1148  * void (*ndo_set_rx_headroom)(struct net_device *dev, int needed_headroom);
1149  *	This function is used to specify the headroom that the skb must
1150  *	consider when allocation skb during packet reception. Setting
1151  *	appropriate rx headroom value allows avoiding skb head copy on
1152  *	forward. Setting a negative value resets the rx headroom to the
1153  *	default value.
1154  * int (*ndo_bpf)(struct net_device *dev, struct netdev_bpf *bpf);
1155  *	This function is used to set or query state related to XDP on the
1156  *	netdevice and manage BPF offload. See definition of
1157  *	enum bpf_netdev_command for details.
1158  * int (*ndo_xdp_xmit)(struct net_device *dev, struct xdp_buff *xdp);
1159  *	This function is used to submit a XDP packet for transmit on a
1160  *	netdevice.
1161  * void (*ndo_xdp_flush)(struct net_device *dev);
1162  *	This function is used to inform the driver to flush a particular
1163  *	xdp tx queue. Must be called on same CPU as xdp_xmit.
1164  */
1165 struct net_device_ops {
1166 	int			(*ndo_init)(struct net_device *dev);
1167 	void			(*ndo_uninit)(struct net_device *dev);
1168 	int			(*ndo_open)(struct net_device *dev);
1169 	int			(*ndo_stop)(struct net_device *dev);
1170 	netdev_tx_t		(*ndo_start_xmit)(struct sk_buff *skb,
1171 						  struct net_device *dev);
1172 	netdev_features_t	(*ndo_features_check)(struct sk_buff *skb,
1173 						      struct net_device *dev,
1174 						      netdev_features_t features);
1175 	u16			(*ndo_select_queue)(struct net_device *dev,
1176 						    struct sk_buff *skb,
1177 						    void *accel_priv,
1178 						    select_queue_fallback_t fallback);
1179 	void			(*ndo_change_rx_flags)(struct net_device *dev,
1180 						       int flags);
1181 	void			(*ndo_set_rx_mode)(struct net_device *dev);
1182 	int			(*ndo_set_mac_address)(struct net_device *dev,
1183 						       void *addr);
1184 	int			(*ndo_validate_addr)(struct net_device *dev);
1185 	int			(*ndo_do_ioctl)(struct net_device *dev,
1186 					        struct ifreq *ifr, int cmd);
1187 	int			(*ndo_set_config)(struct net_device *dev,
1188 					          struct ifmap *map);
1189 	int			(*ndo_change_mtu)(struct net_device *dev,
1190 						  int new_mtu);
1191 	int			(*ndo_neigh_setup)(struct net_device *dev,
1192 						   struct neigh_parms *);
1193 	void			(*ndo_tx_timeout) (struct net_device *dev);
1194 
1195 	void			(*ndo_get_stats64)(struct net_device *dev,
1196 						   struct rtnl_link_stats64 *storage);
1197 	bool			(*ndo_has_offload_stats)(const struct net_device *dev, int attr_id);
1198 	int			(*ndo_get_offload_stats)(int attr_id,
1199 							 const struct net_device *dev,
1200 							 void *attr_data);
1201 	struct net_device_stats* (*ndo_get_stats)(struct net_device *dev);
1202 
1203 	int			(*ndo_vlan_rx_add_vid)(struct net_device *dev,
1204 						       __be16 proto, u16 vid);
1205 	int			(*ndo_vlan_rx_kill_vid)(struct net_device *dev,
1206 						        __be16 proto, u16 vid);
1207 #ifdef CONFIG_NET_POLL_CONTROLLER
1208 	void                    (*ndo_poll_controller)(struct net_device *dev);
1209 	int			(*ndo_netpoll_setup)(struct net_device *dev,
1210 						     struct netpoll_info *info);
1211 	void			(*ndo_netpoll_cleanup)(struct net_device *dev);
1212 #endif
1213 	int			(*ndo_set_vf_mac)(struct net_device *dev,
1214 						  int queue, u8 *mac);
1215 	int			(*ndo_set_vf_vlan)(struct net_device *dev,
1216 						   int queue, u16 vlan,
1217 						   u8 qos, __be16 proto);
1218 	int			(*ndo_set_vf_rate)(struct net_device *dev,
1219 						   int vf, int min_tx_rate,
1220 						   int max_tx_rate);
1221 	int			(*ndo_set_vf_spoofchk)(struct net_device *dev,
1222 						       int vf, bool setting);
1223 	int			(*ndo_set_vf_trust)(struct net_device *dev,
1224 						    int vf, bool setting);
1225 	int			(*ndo_get_vf_config)(struct net_device *dev,
1226 						     int vf,
1227 						     struct ifla_vf_info *ivf);
1228 	int			(*ndo_set_vf_link_state)(struct net_device *dev,
1229 							 int vf, int link_state);
1230 	int			(*ndo_get_vf_stats)(struct net_device *dev,
1231 						    int vf,
1232 						    struct ifla_vf_stats
1233 						    *vf_stats);
1234 	int			(*ndo_set_vf_port)(struct net_device *dev,
1235 						   int vf,
1236 						   struct nlattr *port[]);
1237 	int			(*ndo_get_vf_port)(struct net_device *dev,
1238 						   int vf, struct sk_buff *skb);
1239 	int			(*ndo_set_vf_guid)(struct net_device *dev,
1240 						   int vf, u64 guid,
1241 						   int guid_type);
1242 	int			(*ndo_set_vf_rss_query_en)(
1243 						   struct net_device *dev,
1244 						   int vf, bool setting);
1245 	int			(*ndo_setup_tc)(struct net_device *dev,
1246 						enum tc_setup_type type,
1247 						void *type_data);
1248 #if IS_ENABLED(CONFIG_FCOE)
1249 	int			(*ndo_fcoe_enable)(struct net_device *dev);
1250 	int			(*ndo_fcoe_disable)(struct net_device *dev);
1251 	int			(*ndo_fcoe_ddp_setup)(struct net_device *dev,
1252 						      u16 xid,
1253 						      struct scatterlist *sgl,
1254 						      unsigned int sgc);
1255 	int			(*ndo_fcoe_ddp_done)(struct net_device *dev,
1256 						     u16 xid);
1257 	int			(*ndo_fcoe_ddp_target)(struct net_device *dev,
1258 						       u16 xid,
1259 						       struct scatterlist *sgl,
1260 						       unsigned int sgc);
1261 	int			(*ndo_fcoe_get_hbainfo)(struct net_device *dev,
1262 							struct netdev_fcoe_hbainfo *hbainfo);
1263 #endif
1264 
1265 #if IS_ENABLED(CONFIG_LIBFCOE)
1266 #define NETDEV_FCOE_WWNN 0
1267 #define NETDEV_FCOE_WWPN 1
1268 	int			(*ndo_fcoe_get_wwn)(struct net_device *dev,
1269 						    u64 *wwn, int type);
1270 #endif
1271 
1272 #ifdef CONFIG_RFS_ACCEL
1273 	int			(*ndo_rx_flow_steer)(struct net_device *dev,
1274 						     const struct sk_buff *skb,
1275 						     u16 rxq_index,
1276 						     u32 flow_id);
1277 #endif
1278 	int			(*ndo_add_slave)(struct net_device *dev,
1279 						 struct net_device *slave_dev,
1280 						 struct netlink_ext_ack *extack);
1281 	int			(*ndo_del_slave)(struct net_device *dev,
1282 						 struct net_device *slave_dev);
1283 	netdev_features_t	(*ndo_fix_features)(struct net_device *dev,
1284 						    netdev_features_t features);
1285 	int			(*ndo_set_features)(struct net_device *dev,
1286 						    netdev_features_t features);
1287 	int			(*ndo_neigh_construct)(struct net_device *dev,
1288 						       struct neighbour *n);
1289 	void			(*ndo_neigh_destroy)(struct net_device *dev,
1290 						     struct neighbour *n);
1291 
1292 	int			(*ndo_fdb_add)(struct ndmsg *ndm,
1293 					       struct nlattr *tb[],
1294 					       struct net_device *dev,
1295 					       const unsigned char *addr,
1296 					       u16 vid,
1297 					       u16 flags);
1298 	int			(*ndo_fdb_del)(struct ndmsg *ndm,
1299 					       struct nlattr *tb[],
1300 					       struct net_device *dev,
1301 					       const unsigned char *addr,
1302 					       u16 vid);
1303 	int			(*ndo_fdb_dump)(struct sk_buff *skb,
1304 						struct netlink_callback *cb,
1305 						struct net_device *dev,
1306 						struct net_device *filter_dev,
1307 						int *idx);
1308 
1309 	int			(*ndo_bridge_setlink)(struct net_device *dev,
1310 						      struct nlmsghdr *nlh,
1311 						      u16 flags);
1312 	int			(*ndo_bridge_getlink)(struct sk_buff *skb,
1313 						      u32 pid, u32 seq,
1314 						      struct net_device *dev,
1315 						      u32 filter_mask,
1316 						      int nlflags);
1317 	int			(*ndo_bridge_dellink)(struct net_device *dev,
1318 						      struct nlmsghdr *nlh,
1319 						      u16 flags);
1320 	int			(*ndo_change_carrier)(struct net_device *dev,
1321 						      bool new_carrier);
1322 	int			(*ndo_get_phys_port_id)(struct net_device *dev,
1323 							struct netdev_phys_item_id *ppid);
1324 	int			(*ndo_get_phys_port_name)(struct net_device *dev,
1325 							  char *name, size_t len);
1326 	void			(*ndo_udp_tunnel_add)(struct net_device *dev,
1327 						      struct udp_tunnel_info *ti);
1328 	void			(*ndo_udp_tunnel_del)(struct net_device *dev,
1329 						      struct udp_tunnel_info *ti);
1330 	void*			(*ndo_dfwd_add_station)(struct net_device *pdev,
1331 							struct net_device *dev);
1332 	void			(*ndo_dfwd_del_station)(struct net_device *pdev,
1333 							void *priv);
1334 
1335 	int			(*ndo_get_lock_subclass)(struct net_device *dev);
1336 	int			(*ndo_set_tx_maxrate)(struct net_device *dev,
1337 						      int queue_index,
1338 						      u32 maxrate);
1339 	int			(*ndo_get_iflink)(const struct net_device *dev);
1340 	int			(*ndo_change_proto_down)(struct net_device *dev,
1341 							 bool proto_down);
1342 	int			(*ndo_fill_metadata_dst)(struct net_device *dev,
1343 						       struct sk_buff *skb);
1344 	void			(*ndo_set_rx_headroom)(struct net_device *dev,
1345 						       int needed_headroom);
1346 	int			(*ndo_bpf)(struct net_device *dev,
1347 					   struct netdev_bpf *bpf);
1348 	int			(*ndo_xdp_xmit)(struct net_device *dev,
1349 						struct xdp_buff *xdp);
1350 	void			(*ndo_xdp_flush)(struct net_device *dev);
1351 };
1352 
1353 /**
1354  * enum net_device_priv_flags - &struct net_device priv_flags
1355  *
1356  * These are the &struct net_device, they are only set internally
1357  * by drivers and used in the kernel. These flags are invisible to
1358  * userspace; this means that the order of these flags can change
1359  * during any kernel release.
1360  *
1361  * You should have a pretty good reason to be extending these flags.
1362  *
1363  * @IFF_802_1Q_VLAN: 802.1Q VLAN device
1364  * @IFF_EBRIDGE: Ethernet bridging device
1365  * @IFF_BONDING: bonding master or slave
1366  * @IFF_ISATAP: ISATAP interface (RFC4214)
1367  * @IFF_WAN_HDLC: WAN HDLC device
1368  * @IFF_XMIT_DST_RELEASE: dev_hard_start_xmit() is allowed to
1369  *	release skb->dst
1370  * @IFF_DONT_BRIDGE: disallow bridging this ether dev
1371  * @IFF_DISABLE_NETPOLL: disable netpoll at run-time
1372  * @IFF_MACVLAN_PORT: device used as macvlan port
1373  * @IFF_BRIDGE_PORT: device used as bridge port
1374  * @IFF_OVS_DATAPATH: device used as Open vSwitch datapath port
1375  * @IFF_TX_SKB_SHARING: The interface supports sharing skbs on transmit
1376  * @IFF_UNICAST_FLT: Supports unicast filtering
1377  * @IFF_TEAM_PORT: device used as team port
1378  * @IFF_SUPP_NOFCS: device supports sending custom FCS
1379  * @IFF_LIVE_ADDR_CHANGE: device supports hardware address
1380  *	change when it's running
1381  * @IFF_MACVLAN: Macvlan device
1382  * @IFF_XMIT_DST_RELEASE_PERM: IFF_XMIT_DST_RELEASE not taking into account
1383  *	underlying stacked devices
1384  * @IFF_IPVLAN_MASTER: IPvlan master device
1385  * @IFF_IPVLAN_SLAVE: IPvlan slave device
1386  * @IFF_L3MDEV_MASTER: device is an L3 master device
1387  * @IFF_NO_QUEUE: device can run without qdisc attached
1388  * @IFF_OPENVSWITCH: device is a Open vSwitch master
1389  * @IFF_L3MDEV_SLAVE: device is enslaved to an L3 master device
1390  * @IFF_TEAM: device is a team device
1391  * @IFF_RXFH_CONFIGURED: device has had Rx Flow indirection table configured
1392  * @IFF_PHONY_HEADROOM: the headroom value is controlled by an external
1393  *	entity (i.e. the master device for bridged veth)
1394  * @IFF_MACSEC: device is a MACsec device
1395  */
1396 enum netdev_priv_flags {
1397 	IFF_802_1Q_VLAN			= 1<<0,
1398 	IFF_EBRIDGE			= 1<<1,
1399 	IFF_BONDING			= 1<<2,
1400 	IFF_ISATAP			= 1<<3,
1401 	IFF_WAN_HDLC			= 1<<4,
1402 	IFF_XMIT_DST_RELEASE		= 1<<5,
1403 	IFF_DONT_BRIDGE			= 1<<6,
1404 	IFF_DISABLE_NETPOLL		= 1<<7,
1405 	IFF_MACVLAN_PORT		= 1<<8,
1406 	IFF_BRIDGE_PORT			= 1<<9,
1407 	IFF_OVS_DATAPATH		= 1<<10,
1408 	IFF_TX_SKB_SHARING		= 1<<11,
1409 	IFF_UNICAST_FLT			= 1<<12,
1410 	IFF_TEAM_PORT			= 1<<13,
1411 	IFF_SUPP_NOFCS			= 1<<14,
1412 	IFF_LIVE_ADDR_CHANGE		= 1<<15,
1413 	IFF_MACVLAN			= 1<<16,
1414 	IFF_XMIT_DST_RELEASE_PERM	= 1<<17,
1415 	IFF_IPVLAN_MASTER		= 1<<18,
1416 	IFF_IPVLAN_SLAVE		= 1<<19,
1417 	IFF_L3MDEV_MASTER		= 1<<20,
1418 	IFF_NO_QUEUE			= 1<<21,
1419 	IFF_OPENVSWITCH			= 1<<22,
1420 	IFF_L3MDEV_SLAVE		= 1<<23,
1421 	IFF_TEAM			= 1<<24,
1422 	IFF_RXFH_CONFIGURED		= 1<<25,
1423 	IFF_PHONY_HEADROOM		= 1<<26,
1424 	IFF_MACSEC			= 1<<27,
1425 };
1426 
1427 #define IFF_802_1Q_VLAN			IFF_802_1Q_VLAN
1428 #define IFF_EBRIDGE			IFF_EBRIDGE
1429 #define IFF_BONDING			IFF_BONDING
1430 #define IFF_ISATAP			IFF_ISATAP
1431 #define IFF_WAN_HDLC			IFF_WAN_HDLC
1432 #define IFF_XMIT_DST_RELEASE		IFF_XMIT_DST_RELEASE
1433 #define IFF_DONT_BRIDGE			IFF_DONT_BRIDGE
1434 #define IFF_DISABLE_NETPOLL		IFF_DISABLE_NETPOLL
1435 #define IFF_MACVLAN_PORT		IFF_MACVLAN_PORT
1436 #define IFF_BRIDGE_PORT			IFF_BRIDGE_PORT
1437 #define IFF_OVS_DATAPATH		IFF_OVS_DATAPATH
1438 #define IFF_TX_SKB_SHARING		IFF_TX_SKB_SHARING
1439 #define IFF_UNICAST_FLT			IFF_UNICAST_FLT
1440 #define IFF_TEAM_PORT			IFF_TEAM_PORT
1441 #define IFF_SUPP_NOFCS			IFF_SUPP_NOFCS
1442 #define IFF_LIVE_ADDR_CHANGE		IFF_LIVE_ADDR_CHANGE
1443 #define IFF_MACVLAN			IFF_MACVLAN
1444 #define IFF_XMIT_DST_RELEASE_PERM	IFF_XMIT_DST_RELEASE_PERM
1445 #define IFF_IPVLAN_MASTER		IFF_IPVLAN_MASTER
1446 #define IFF_IPVLAN_SLAVE		IFF_IPVLAN_SLAVE
1447 #define IFF_L3MDEV_MASTER		IFF_L3MDEV_MASTER
1448 #define IFF_NO_QUEUE			IFF_NO_QUEUE
1449 #define IFF_OPENVSWITCH			IFF_OPENVSWITCH
1450 #define IFF_L3MDEV_SLAVE		IFF_L3MDEV_SLAVE
1451 #define IFF_TEAM			IFF_TEAM
1452 #define IFF_RXFH_CONFIGURED		IFF_RXFH_CONFIGURED
1453 #define IFF_MACSEC			IFF_MACSEC
1454 
1455 /**
1456  *	struct net_device - The DEVICE structure.
1457  *
1458  *	Actually, this whole structure is a big mistake.  It mixes I/O
1459  *	data with strictly "high-level" data, and it has to know about
1460  *	almost every data structure used in the INET module.
1461  *
1462  *	@name:	This is the first field of the "visible" part of this structure
1463  *		(i.e. as seen by users in the "Space.c" file).  It is the name
1464  *		of the interface.
1465  *
1466  *	@name_hlist: 	Device name hash chain, please keep it close to name[]
1467  *	@ifalias:	SNMP alias
1468  *	@mem_end:	Shared memory end
1469  *	@mem_start:	Shared memory start
1470  *	@base_addr:	Device I/O address
1471  *	@irq:		Device IRQ number
1472  *
1473  *	@state:		Generic network queuing layer state, see netdev_state_t
1474  *	@dev_list:	The global list of network devices
1475  *	@napi_list:	List entry used for polling NAPI devices
1476  *	@unreg_list:	List entry  when we are unregistering the
1477  *			device; see the function unregister_netdev
1478  *	@close_list:	List entry used when we are closing the device
1479  *	@ptype_all:     Device-specific packet handlers for all protocols
1480  *	@ptype_specific: Device-specific, protocol-specific packet handlers
1481  *
1482  *	@adj_list:	Directly linked devices, like slaves for bonding
1483  *	@features:	Currently active device features
1484  *	@hw_features:	User-changeable features
1485  *
1486  *	@wanted_features:	User-requested features
1487  *	@vlan_features:		Mask of features inheritable by VLAN devices
1488  *
1489  *	@hw_enc_features:	Mask of features inherited by encapsulating devices
1490  *				This field indicates what encapsulation
1491  *				offloads the hardware is capable of doing,
1492  *				and drivers will need to set them appropriately.
1493  *
1494  *	@mpls_features:	Mask of features inheritable by MPLS
1495  *
1496  *	@ifindex:	interface index
1497  *	@group:		The group the device belongs to
1498  *
1499  *	@stats:		Statistics struct, which was left as a legacy, use
1500  *			rtnl_link_stats64 instead
1501  *
1502  *	@rx_dropped:	Dropped packets by core network,
1503  *			do not use this in drivers
1504  *	@tx_dropped:	Dropped packets by core network,
1505  *			do not use this in drivers
1506  *	@rx_nohandler:	nohandler dropped packets by core network on
1507  *			inactive devices, do not use this in drivers
1508  *	@carrier_up_count:	Number of times the carrier has been up
1509  *	@carrier_down_count:	Number of times the carrier has been down
1510  *
1511  *	@wireless_handlers:	List of functions to handle Wireless Extensions,
1512  *				instead of ioctl,
1513  *				see <net/iw_handler.h> for details.
1514  *	@wireless_data:	Instance data managed by the core of wireless extensions
1515  *
1516  *	@netdev_ops:	Includes several pointers to callbacks,
1517  *			if one wants to override the ndo_*() functions
1518  *	@ethtool_ops:	Management operations
1519  *	@ndisc_ops:	Includes callbacks for different IPv6 neighbour
1520  *			discovery handling. Necessary for e.g. 6LoWPAN.
1521  *	@header_ops:	Includes callbacks for creating,parsing,caching,etc
1522  *			of Layer 2 headers.
1523  *
1524  *	@flags:		Interface flags (a la BSD)
1525  *	@priv_flags:	Like 'flags' but invisible to userspace,
1526  *			see if.h for the definitions
1527  *	@gflags:	Global flags ( kept as legacy )
1528  *	@padded:	How much padding added by alloc_netdev()
1529  *	@operstate:	RFC2863 operstate
1530  *	@link_mode:	Mapping policy to operstate
1531  *	@if_port:	Selectable AUI, TP, ...
1532  *	@dma:		DMA channel
1533  *	@mtu:		Interface MTU value
1534  *	@min_mtu:	Interface Minimum MTU value
1535  *	@max_mtu:	Interface Maximum MTU value
1536  *	@type:		Interface hardware type
1537  *	@hard_header_len: Maximum hardware header length.
1538  *	@min_header_len:  Minimum hardware header length
1539  *
1540  *	@needed_headroom: Extra headroom the hardware may need, but not in all
1541  *			  cases can this be guaranteed
1542  *	@needed_tailroom: Extra tailroom the hardware may need, but not in all
1543  *			  cases can this be guaranteed. Some cases also use
1544  *			  LL_MAX_HEADER instead to allocate the skb
1545  *
1546  *	interface address info:
1547  *
1548  * 	@perm_addr:		Permanent hw address
1549  * 	@addr_assign_type:	Hw address assignment type
1550  * 	@addr_len:		Hardware address length
1551  *	@neigh_priv_len:	Used in neigh_alloc()
1552  * 	@dev_id:		Used to differentiate devices that share
1553  * 				the same link layer address
1554  * 	@dev_port:		Used to differentiate devices that share
1555  * 				the same function
1556  *	@addr_list_lock:	XXX: need comments on this one
1557  *	@uc_promisc:		Counter that indicates promiscuous mode
1558  *				has been enabled due to the need to listen to
1559  *				additional unicast addresses in a device that
1560  *				does not implement ndo_set_rx_mode()
1561  *	@uc:			unicast mac addresses
1562  *	@mc:			multicast mac addresses
1563  *	@dev_addrs:		list of device hw addresses
1564  *	@queues_kset:		Group of all Kobjects in the Tx and RX queues
1565  *	@promiscuity:		Number of times the NIC is told to work in
1566  *				promiscuous mode; if it becomes 0 the NIC will
1567  *				exit promiscuous mode
1568  *	@allmulti:		Counter, enables or disables allmulticast mode
1569  *
1570  *	@vlan_info:	VLAN info
1571  *	@dsa_ptr:	dsa specific data
1572  *	@tipc_ptr:	TIPC specific data
1573  *	@atalk_ptr:	AppleTalk link
1574  *	@ip_ptr:	IPv4 specific data
1575  *	@dn_ptr:	DECnet specific data
1576  *	@ip6_ptr:	IPv6 specific data
1577  *	@ax25_ptr:	AX.25 specific data
1578  *	@ieee80211_ptr:	IEEE 802.11 specific data, assign before registering
1579  *
1580  *	@dev_addr:	Hw address (before bcast,
1581  *			because most packets are unicast)
1582  *
1583  *	@_rx:			Array of RX queues
1584  *	@num_rx_queues:		Number of RX queues
1585  *				allocated at register_netdev() time
1586  *	@real_num_rx_queues: 	Number of RX queues currently active in device
1587  *
1588  *	@rx_handler:		handler for received packets
1589  *	@rx_handler_data: 	XXX: need comments on this one
1590  *	@miniq_ingress:		ingress/clsact qdisc specific data for
1591  *				ingress processing
1592  *	@ingress_queue:		XXX: need comments on this one
1593  *	@broadcast:		hw bcast address
1594  *
1595  *	@rx_cpu_rmap:	CPU reverse-mapping for RX completion interrupts,
1596  *			indexed by RX queue number. Assigned by driver.
1597  *			This must only be set if the ndo_rx_flow_steer
1598  *			operation is defined
1599  *	@index_hlist:		Device index hash chain
1600  *
1601  *	@_tx:			Array of TX queues
1602  *	@num_tx_queues:		Number of TX queues allocated at alloc_netdev_mq() time
1603  *	@real_num_tx_queues: 	Number of TX queues currently active in device
1604  *	@qdisc:			Root qdisc from userspace point of view
1605  *	@tx_queue_len:		Max frames per queue allowed
1606  *	@tx_global_lock: 	XXX: need comments on this one
1607  *
1608  *	@xps_maps:	XXX: need comments on this one
1609  *	@miniq_egress:		clsact qdisc specific data for
1610  *				egress processing
1611  *	@watchdog_timeo:	Represents the timeout that is used by
1612  *				the watchdog (see dev_watchdog())
1613  *	@watchdog_timer:	List of timers
1614  *
1615  *	@pcpu_refcnt:		Number of references to this device
1616  *	@todo_list:		Delayed register/unregister
1617  *	@link_watch_list:	XXX: need comments on this one
1618  *
1619  *	@reg_state:		Register/unregister state machine
1620  *	@dismantle:		Device is going to be freed
1621  *	@rtnl_link_state:	This enum represents the phases of creating
1622  *				a new link
1623  *
1624  *	@needs_free_netdev:	Should unregister perform free_netdev?
1625  *	@priv_destructor:	Called from unregister
1626  *	@npinfo:		XXX: need comments on this one
1627  * 	@nd_net:		Network namespace this network device is inside
1628  *
1629  * 	@ml_priv:	Mid-layer private
1630  * 	@lstats:	Loopback statistics
1631  * 	@tstats:	Tunnel statistics
1632  * 	@dstats:	Dummy statistics
1633  * 	@vstats:	Virtual ethernet statistics
1634  *
1635  *	@garp_port:	GARP
1636  *	@mrp_port:	MRP
1637  *
1638  *	@dev:		Class/net/name entry
1639  *	@sysfs_groups:	Space for optional device, statistics and wireless
1640  *			sysfs groups
1641  *
1642  *	@sysfs_rx_queue_group:	Space for optional per-rx queue attributes
1643  *	@rtnl_link_ops:	Rtnl_link_ops
1644  *
1645  *	@gso_max_size:	Maximum size of generic segmentation offload
1646  *	@gso_max_segs:	Maximum number of segments that can be passed to the
1647  *			NIC for GSO
1648  *
1649  *	@dcbnl_ops:	Data Center Bridging netlink ops
1650  *	@num_tc:	Number of traffic classes in the net device
1651  *	@tc_to_txq:	XXX: need comments on this one
1652  *	@prio_tc_map:	XXX: need comments on this one
1653  *
1654  *	@fcoe_ddp_xid:	Max exchange id for FCoE LRO by ddp
1655  *
1656  *	@priomap:	XXX: need comments on this one
1657  *	@phydev:	Physical device may attach itself
1658  *			for hardware timestamping
1659  *
1660  *	@qdisc_tx_busylock: lockdep class annotating Qdisc->busylock spinlock
1661  *	@qdisc_running_key: lockdep class annotating Qdisc->running seqcount
1662  *
1663  *	@proto_down:	protocol port state information can be sent to the
1664  *			switch driver and used to set the phys state of the
1665  *			switch port.
1666  *
1667  *	FIXME: cleanup struct net_device such that network protocol info
1668  *	moves out.
1669  */
1670 
1671 struct net_device {
1672 	char			name[IFNAMSIZ];
1673 	struct hlist_node	name_hlist;
1674 	struct dev_ifalias	__rcu *ifalias;
1675 	/*
1676 	 *	I/O specific fields
1677 	 *	FIXME: Merge these and struct ifmap into one
1678 	 */
1679 	unsigned long		mem_end;
1680 	unsigned long		mem_start;
1681 	unsigned long		base_addr;
1682 	int			irq;
1683 
1684 	/*
1685 	 *	Some hardware also needs these fields (state,dev_list,
1686 	 *	napi_list,unreg_list,close_list) but they are not
1687 	 *	part of the usual set specified in Space.c.
1688 	 */
1689 
1690 	unsigned long		state;
1691 
1692 	struct list_head	dev_list;
1693 	struct list_head	napi_list;
1694 	struct list_head	unreg_list;
1695 	struct list_head	close_list;
1696 	struct list_head	ptype_all;
1697 	struct list_head	ptype_specific;
1698 
1699 	struct {
1700 		struct list_head upper;
1701 		struct list_head lower;
1702 	} adj_list;
1703 
1704 	netdev_features_t	features;
1705 	netdev_features_t	hw_features;
1706 	netdev_features_t	wanted_features;
1707 	netdev_features_t	vlan_features;
1708 	netdev_features_t	hw_enc_features;
1709 	netdev_features_t	mpls_features;
1710 	netdev_features_t	gso_partial_features;
1711 
1712 	int			ifindex;
1713 	int			group;
1714 
1715 	struct net_device_stats	stats;
1716 
1717 	atomic_long_t		rx_dropped;
1718 	atomic_long_t		tx_dropped;
1719 	atomic_long_t		rx_nohandler;
1720 
1721 	/* Stats to monitor link on/off, flapping */
1722 	atomic_t		carrier_up_count;
1723 	atomic_t		carrier_down_count;
1724 
1725 #ifdef CONFIG_WIRELESS_EXT
1726 	const struct iw_handler_def *wireless_handlers;
1727 	struct iw_public_data	*wireless_data;
1728 #endif
1729 	const struct net_device_ops *netdev_ops;
1730 	const struct ethtool_ops *ethtool_ops;
1731 #ifdef CONFIG_NET_SWITCHDEV
1732 	const struct switchdev_ops *switchdev_ops;
1733 #endif
1734 #ifdef CONFIG_NET_L3_MASTER_DEV
1735 	const struct l3mdev_ops	*l3mdev_ops;
1736 #endif
1737 #if IS_ENABLED(CONFIG_IPV6)
1738 	const struct ndisc_ops *ndisc_ops;
1739 #endif
1740 
1741 #ifdef CONFIG_XFRM_OFFLOAD
1742 	const struct xfrmdev_ops *xfrmdev_ops;
1743 #endif
1744 
1745 	const struct header_ops *header_ops;
1746 
1747 	unsigned int		flags;
1748 	unsigned int		priv_flags;
1749 
1750 	unsigned short		gflags;
1751 	unsigned short		padded;
1752 
1753 	unsigned char		operstate;
1754 	unsigned char		link_mode;
1755 
1756 	unsigned char		if_port;
1757 	unsigned char		dma;
1758 
1759 	unsigned int		mtu;
1760 	unsigned int		min_mtu;
1761 	unsigned int		max_mtu;
1762 	unsigned short		type;
1763 	unsigned short		hard_header_len;
1764 	unsigned char		min_header_len;
1765 
1766 	unsigned short		needed_headroom;
1767 	unsigned short		needed_tailroom;
1768 
1769 	/* Interface address info. */
1770 	unsigned char		perm_addr[MAX_ADDR_LEN];
1771 	unsigned char		addr_assign_type;
1772 	unsigned char		addr_len;
1773 	unsigned short		neigh_priv_len;
1774 	unsigned short          dev_id;
1775 	unsigned short          dev_port;
1776 	spinlock_t		addr_list_lock;
1777 	unsigned char		name_assign_type;
1778 	bool			uc_promisc;
1779 	struct netdev_hw_addr_list	uc;
1780 	struct netdev_hw_addr_list	mc;
1781 	struct netdev_hw_addr_list	dev_addrs;
1782 
1783 #ifdef CONFIG_SYSFS
1784 	struct kset		*queues_kset;
1785 #endif
1786 	unsigned int		promiscuity;
1787 	unsigned int		allmulti;
1788 
1789 
1790 	/* Protocol-specific pointers */
1791 
1792 #if IS_ENABLED(CONFIG_VLAN_8021Q)
1793 	struct vlan_info __rcu	*vlan_info;
1794 #endif
1795 #if IS_ENABLED(CONFIG_NET_DSA)
1796 	struct dsa_port		*dsa_ptr;
1797 #endif
1798 #if IS_ENABLED(CONFIG_TIPC)
1799 	struct tipc_bearer __rcu *tipc_ptr;
1800 #endif
1801 #if IS_ENABLED(CONFIG_IRDA) || IS_ENABLED(CONFIG_ATALK)
1802 	void 			*atalk_ptr;
1803 #endif
1804 	struct in_device __rcu	*ip_ptr;
1805 #if IS_ENABLED(CONFIG_DECNET)
1806 	struct dn_dev __rcu     *dn_ptr;
1807 #endif
1808 	struct inet6_dev __rcu	*ip6_ptr;
1809 #if IS_ENABLED(CONFIG_AX25)
1810 	void			*ax25_ptr;
1811 #endif
1812 	struct wireless_dev	*ieee80211_ptr;
1813 	struct wpan_dev		*ieee802154_ptr;
1814 #if IS_ENABLED(CONFIG_MPLS_ROUTING)
1815 	struct mpls_dev __rcu	*mpls_ptr;
1816 #endif
1817 
1818 /*
1819  * Cache lines mostly used on receive path (including eth_type_trans())
1820  */
1821 	/* Interface address info used in eth_type_trans() */
1822 	unsigned char		*dev_addr;
1823 
1824 	struct netdev_rx_queue	*_rx;
1825 	unsigned int		num_rx_queues;
1826 	unsigned int		real_num_rx_queues;
1827 
1828 	struct bpf_prog __rcu	*xdp_prog;
1829 	unsigned long		gro_flush_timeout;
1830 	rx_handler_func_t __rcu	*rx_handler;
1831 	void __rcu		*rx_handler_data;
1832 
1833 #ifdef CONFIG_NET_CLS_ACT
1834 	struct mini_Qdisc __rcu	*miniq_ingress;
1835 #endif
1836 	struct netdev_queue __rcu *ingress_queue;
1837 #ifdef CONFIG_NETFILTER_INGRESS
1838 	struct nf_hook_entries __rcu *nf_hooks_ingress;
1839 #endif
1840 
1841 	unsigned char		broadcast[MAX_ADDR_LEN];
1842 #ifdef CONFIG_RFS_ACCEL
1843 	struct cpu_rmap		*rx_cpu_rmap;
1844 #endif
1845 	struct hlist_node	index_hlist;
1846 
1847 /*
1848  * Cache lines mostly used on transmit path
1849  */
1850 	struct netdev_queue	*_tx ____cacheline_aligned_in_smp;
1851 	unsigned int		num_tx_queues;
1852 	unsigned int		real_num_tx_queues;
1853 	struct Qdisc		*qdisc;
1854 #ifdef CONFIG_NET_SCHED
1855 	DECLARE_HASHTABLE	(qdisc_hash, 4);
1856 #endif
1857 	unsigned int		tx_queue_len;
1858 	spinlock_t		tx_global_lock;
1859 	int			watchdog_timeo;
1860 
1861 #ifdef CONFIG_XPS
1862 	struct xps_dev_maps __rcu *xps_maps;
1863 #endif
1864 #ifdef CONFIG_NET_CLS_ACT
1865 	struct mini_Qdisc __rcu	*miniq_egress;
1866 #endif
1867 
1868 	/* These may be needed for future network-power-down code. */
1869 	struct timer_list	watchdog_timer;
1870 
1871 	int __percpu		*pcpu_refcnt;
1872 	struct list_head	todo_list;
1873 
1874 	struct list_head	link_watch_list;
1875 
1876 	enum { NETREG_UNINITIALIZED=0,
1877 	       NETREG_REGISTERED,	/* completed register_netdevice */
1878 	       NETREG_UNREGISTERING,	/* called unregister_netdevice */
1879 	       NETREG_UNREGISTERED,	/* completed unregister todo */
1880 	       NETREG_RELEASED,		/* called free_netdev */
1881 	       NETREG_DUMMY,		/* dummy device for NAPI poll */
1882 	} reg_state:8;
1883 
1884 	bool dismantle;
1885 
1886 	enum {
1887 		RTNL_LINK_INITIALIZED,
1888 		RTNL_LINK_INITIALIZING,
1889 	} rtnl_link_state:16;
1890 
1891 	bool needs_free_netdev;
1892 	void (*priv_destructor)(struct net_device *dev);
1893 
1894 #ifdef CONFIG_NETPOLL
1895 	struct netpoll_info __rcu	*npinfo;
1896 #endif
1897 
1898 	possible_net_t			nd_net;
1899 
1900 	/* mid-layer private */
1901 	union {
1902 		void					*ml_priv;
1903 		struct pcpu_lstats __percpu		*lstats;
1904 		struct pcpu_sw_netstats __percpu	*tstats;
1905 		struct pcpu_dstats __percpu		*dstats;
1906 		struct pcpu_vstats __percpu		*vstats;
1907 	};
1908 
1909 #if IS_ENABLED(CONFIG_GARP)
1910 	struct garp_port __rcu	*garp_port;
1911 #endif
1912 #if IS_ENABLED(CONFIG_MRP)
1913 	struct mrp_port __rcu	*mrp_port;
1914 #endif
1915 
1916 	struct device		dev;
1917 	const struct attribute_group *sysfs_groups[4];
1918 	const struct attribute_group *sysfs_rx_queue_group;
1919 
1920 	const struct rtnl_link_ops *rtnl_link_ops;
1921 
1922 	/* for setting kernel sock attribute on TCP connection setup */
1923 #define GSO_MAX_SIZE		65536
1924 	unsigned int		gso_max_size;
1925 #define GSO_MAX_SEGS		65535
1926 	u16			gso_max_segs;
1927 
1928 #ifdef CONFIG_DCB
1929 	const struct dcbnl_rtnl_ops *dcbnl_ops;
1930 #endif
1931 	u8			num_tc;
1932 	struct netdev_tc_txq	tc_to_txq[TC_MAX_QUEUE];
1933 	u8			prio_tc_map[TC_BITMASK + 1];
1934 
1935 #if IS_ENABLED(CONFIG_FCOE)
1936 	unsigned int		fcoe_ddp_xid;
1937 #endif
1938 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
1939 	struct netprio_map __rcu *priomap;
1940 #endif
1941 	struct phy_device	*phydev;
1942 	struct lock_class_key	*qdisc_tx_busylock;
1943 	struct lock_class_key	*qdisc_running_key;
1944 	bool			proto_down;
1945 };
1946 #define to_net_dev(d) container_of(d, struct net_device, dev)
1947 
1948 static inline bool netif_elide_gro(const struct net_device *dev)
1949 {
1950 	if (!(dev->features & NETIF_F_GRO) || dev->xdp_prog)
1951 		return true;
1952 	return false;
1953 }
1954 
1955 #define	NETDEV_ALIGN		32
1956 
1957 static inline
1958 int netdev_get_prio_tc_map(const struct net_device *dev, u32 prio)
1959 {
1960 	return dev->prio_tc_map[prio & TC_BITMASK];
1961 }
1962 
1963 static inline
1964 int netdev_set_prio_tc_map(struct net_device *dev, u8 prio, u8 tc)
1965 {
1966 	if (tc >= dev->num_tc)
1967 		return -EINVAL;
1968 
1969 	dev->prio_tc_map[prio & TC_BITMASK] = tc & TC_BITMASK;
1970 	return 0;
1971 }
1972 
1973 int netdev_txq_to_tc(struct net_device *dev, unsigned int txq);
1974 void netdev_reset_tc(struct net_device *dev);
1975 int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset);
1976 int netdev_set_num_tc(struct net_device *dev, u8 num_tc);
1977 
1978 static inline
1979 int netdev_get_num_tc(struct net_device *dev)
1980 {
1981 	return dev->num_tc;
1982 }
1983 
1984 static inline
1985 struct netdev_queue *netdev_get_tx_queue(const struct net_device *dev,
1986 					 unsigned int index)
1987 {
1988 	return &dev->_tx[index];
1989 }
1990 
1991 static inline struct netdev_queue *skb_get_tx_queue(const struct net_device *dev,
1992 						    const struct sk_buff *skb)
1993 {
1994 	return netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
1995 }
1996 
1997 static inline void netdev_for_each_tx_queue(struct net_device *dev,
1998 					    void (*f)(struct net_device *,
1999 						      struct netdev_queue *,
2000 						      void *),
2001 					    void *arg)
2002 {
2003 	unsigned int i;
2004 
2005 	for (i = 0; i < dev->num_tx_queues; i++)
2006 		f(dev, &dev->_tx[i], arg);
2007 }
2008 
2009 #define netdev_lockdep_set_classes(dev)				\
2010 {								\
2011 	static struct lock_class_key qdisc_tx_busylock_key;	\
2012 	static struct lock_class_key qdisc_running_key;		\
2013 	static struct lock_class_key qdisc_xmit_lock_key;	\
2014 	static struct lock_class_key dev_addr_list_lock_key;	\
2015 	unsigned int i;						\
2016 								\
2017 	(dev)->qdisc_tx_busylock = &qdisc_tx_busylock_key;	\
2018 	(dev)->qdisc_running_key = &qdisc_running_key;		\
2019 	lockdep_set_class(&(dev)->addr_list_lock,		\
2020 			  &dev_addr_list_lock_key); 		\
2021 	for (i = 0; i < (dev)->num_tx_queues; i++)		\
2022 		lockdep_set_class(&(dev)->_tx[i]._xmit_lock,	\
2023 				  &qdisc_xmit_lock_key);	\
2024 }
2025 
2026 struct netdev_queue *netdev_pick_tx(struct net_device *dev,
2027 				    struct sk_buff *skb,
2028 				    void *accel_priv);
2029 
2030 /* returns the headroom that the master device needs to take in account
2031  * when forwarding to this dev
2032  */
2033 static inline unsigned netdev_get_fwd_headroom(struct net_device *dev)
2034 {
2035 	return dev->priv_flags & IFF_PHONY_HEADROOM ? 0 : dev->needed_headroom;
2036 }
2037 
2038 static inline void netdev_set_rx_headroom(struct net_device *dev, int new_hr)
2039 {
2040 	if (dev->netdev_ops->ndo_set_rx_headroom)
2041 		dev->netdev_ops->ndo_set_rx_headroom(dev, new_hr);
2042 }
2043 
2044 /* set the device rx headroom to the dev's default */
2045 static inline void netdev_reset_rx_headroom(struct net_device *dev)
2046 {
2047 	netdev_set_rx_headroom(dev, -1);
2048 }
2049 
2050 /*
2051  * Net namespace inlines
2052  */
2053 static inline
2054 struct net *dev_net(const struct net_device *dev)
2055 {
2056 	return read_pnet(&dev->nd_net);
2057 }
2058 
2059 static inline
2060 void dev_net_set(struct net_device *dev, struct net *net)
2061 {
2062 	write_pnet(&dev->nd_net, net);
2063 }
2064 
2065 /**
2066  *	netdev_priv - access network device private data
2067  *	@dev: network device
2068  *
2069  * Get network device private data
2070  */
2071 static inline void *netdev_priv(const struct net_device *dev)
2072 {
2073 	return (char *)dev + ALIGN(sizeof(struct net_device), NETDEV_ALIGN);
2074 }
2075 
2076 /* Set the sysfs physical device reference for the network logical device
2077  * if set prior to registration will cause a symlink during initialization.
2078  */
2079 #define SET_NETDEV_DEV(net, pdev)	((net)->dev.parent = (pdev))
2080 
2081 /* Set the sysfs device type for the network logical device to allow
2082  * fine-grained identification of different network device types. For
2083  * example Ethernet, Wireless LAN, Bluetooth, WiMAX etc.
2084  */
2085 #define SET_NETDEV_DEVTYPE(net, devtype)	((net)->dev.type = (devtype))
2086 
2087 /* Default NAPI poll() weight
2088  * Device drivers are strongly advised to not use bigger value
2089  */
2090 #define NAPI_POLL_WEIGHT 64
2091 
2092 /**
2093  *	netif_napi_add - initialize a NAPI context
2094  *	@dev:  network device
2095  *	@napi: NAPI context
2096  *	@poll: polling function
2097  *	@weight: default weight
2098  *
2099  * netif_napi_add() must be used to initialize a NAPI context prior to calling
2100  * *any* of the other NAPI-related functions.
2101  */
2102 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
2103 		    int (*poll)(struct napi_struct *, int), int weight);
2104 
2105 /**
2106  *	netif_tx_napi_add - initialize a NAPI context
2107  *	@dev:  network device
2108  *	@napi: NAPI context
2109  *	@poll: polling function
2110  *	@weight: default weight
2111  *
2112  * This variant of netif_napi_add() should be used from drivers using NAPI
2113  * to exclusively poll a TX queue.
2114  * This will avoid we add it into napi_hash[], thus polluting this hash table.
2115  */
2116 static inline void netif_tx_napi_add(struct net_device *dev,
2117 				     struct napi_struct *napi,
2118 				     int (*poll)(struct napi_struct *, int),
2119 				     int weight)
2120 {
2121 	set_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state);
2122 	netif_napi_add(dev, napi, poll, weight);
2123 }
2124 
2125 /**
2126  *  netif_napi_del - remove a NAPI context
2127  *  @napi: NAPI context
2128  *
2129  *  netif_napi_del() removes a NAPI context from the network device NAPI list
2130  */
2131 void netif_napi_del(struct napi_struct *napi);
2132 
2133 struct napi_gro_cb {
2134 	/* Virtual address of skb_shinfo(skb)->frags[0].page + offset. */
2135 	void	*frag0;
2136 
2137 	/* Length of frag0. */
2138 	unsigned int frag0_len;
2139 
2140 	/* This indicates where we are processing relative to skb->data. */
2141 	int	data_offset;
2142 
2143 	/* This is non-zero if the packet cannot be merged with the new skb. */
2144 	u16	flush;
2145 
2146 	/* Save the IP ID here and check when we get to the transport layer */
2147 	u16	flush_id;
2148 
2149 	/* Number of segments aggregated. */
2150 	u16	count;
2151 
2152 	/* Start offset for remote checksum offload */
2153 	u16	gro_remcsum_start;
2154 
2155 	/* jiffies when first packet was created/queued */
2156 	unsigned long age;
2157 
2158 	/* Used in ipv6_gro_receive() and foo-over-udp */
2159 	u16	proto;
2160 
2161 	/* This is non-zero if the packet may be of the same flow. */
2162 	u8	same_flow:1;
2163 
2164 	/* Used in tunnel GRO receive */
2165 	u8	encap_mark:1;
2166 
2167 	/* GRO checksum is valid */
2168 	u8	csum_valid:1;
2169 
2170 	/* Number of checksums via CHECKSUM_UNNECESSARY */
2171 	u8	csum_cnt:3;
2172 
2173 	/* Free the skb? */
2174 	u8	free:2;
2175 #define NAPI_GRO_FREE		  1
2176 #define NAPI_GRO_FREE_STOLEN_HEAD 2
2177 
2178 	/* Used in foo-over-udp, set in udp[46]_gro_receive */
2179 	u8	is_ipv6:1;
2180 
2181 	/* Used in GRE, set in fou/gue_gro_receive */
2182 	u8	is_fou:1;
2183 
2184 	/* Used to determine if flush_id can be ignored */
2185 	u8	is_atomic:1;
2186 
2187 	/* Number of gro_receive callbacks this packet already went through */
2188 	u8 recursion_counter:4;
2189 
2190 	/* 1 bit hole */
2191 
2192 	/* used to support CHECKSUM_COMPLETE for tunneling protocols */
2193 	__wsum	csum;
2194 
2195 	/* used in skb_gro_receive() slow path */
2196 	struct sk_buff *last;
2197 };
2198 
2199 #define NAPI_GRO_CB(skb) ((struct napi_gro_cb *)(skb)->cb)
2200 
2201 #define GRO_RECURSION_LIMIT 15
2202 static inline int gro_recursion_inc_test(struct sk_buff *skb)
2203 {
2204 	return ++NAPI_GRO_CB(skb)->recursion_counter == GRO_RECURSION_LIMIT;
2205 }
2206 
2207 typedef struct sk_buff **(*gro_receive_t)(struct sk_buff **, struct sk_buff *);
2208 static inline struct sk_buff **call_gro_receive(gro_receive_t cb,
2209 						struct sk_buff **head,
2210 						struct sk_buff *skb)
2211 {
2212 	if (unlikely(gro_recursion_inc_test(skb))) {
2213 		NAPI_GRO_CB(skb)->flush |= 1;
2214 		return NULL;
2215 	}
2216 
2217 	return cb(head, skb);
2218 }
2219 
2220 typedef struct sk_buff **(*gro_receive_sk_t)(struct sock *, struct sk_buff **,
2221 					     struct sk_buff *);
2222 static inline struct sk_buff **call_gro_receive_sk(gro_receive_sk_t cb,
2223 						   struct sock *sk,
2224 						   struct sk_buff **head,
2225 						   struct sk_buff *skb)
2226 {
2227 	if (unlikely(gro_recursion_inc_test(skb))) {
2228 		NAPI_GRO_CB(skb)->flush |= 1;
2229 		return NULL;
2230 	}
2231 
2232 	return cb(sk, head, skb);
2233 }
2234 
2235 struct packet_type {
2236 	__be16			type;	/* This is really htons(ether_type). */
2237 	struct net_device	*dev;	/* NULL is wildcarded here	     */
2238 	int			(*func) (struct sk_buff *,
2239 					 struct net_device *,
2240 					 struct packet_type *,
2241 					 struct net_device *);
2242 	bool			(*id_match)(struct packet_type *ptype,
2243 					    struct sock *sk);
2244 	void			*af_packet_priv;
2245 	struct list_head	list;
2246 };
2247 
2248 struct offload_callbacks {
2249 	struct sk_buff		*(*gso_segment)(struct sk_buff *skb,
2250 						netdev_features_t features);
2251 	struct sk_buff		**(*gro_receive)(struct sk_buff **head,
2252 						 struct sk_buff *skb);
2253 	int			(*gro_complete)(struct sk_buff *skb, int nhoff);
2254 };
2255 
2256 struct packet_offload {
2257 	__be16			 type;	/* This is really htons(ether_type). */
2258 	u16			 priority;
2259 	struct offload_callbacks callbacks;
2260 	struct list_head	 list;
2261 };
2262 
2263 /* often modified stats are per-CPU, other are shared (netdev->stats) */
2264 struct pcpu_sw_netstats {
2265 	u64     rx_packets;
2266 	u64     rx_bytes;
2267 	u64     tx_packets;
2268 	u64     tx_bytes;
2269 	struct u64_stats_sync   syncp;
2270 };
2271 
2272 #define __netdev_alloc_pcpu_stats(type, gfp)				\
2273 ({									\
2274 	typeof(type) __percpu *pcpu_stats = alloc_percpu_gfp(type, gfp);\
2275 	if (pcpu_stats)	{						\
2276 		int __cpu;						\
2277 		for_each_possible_cpu(__cpu) {				\
2278 			typeof(type) *stat;				\
2279 			stat = per_cpu_ptr(pcpu_stats, __cpu);		\
2280 			u64_stats_init(&stat->syncp);			\
2281 		}							\
2282 	}								\
2283 	pcpu_stats;							\
2284 })
2285 
2286 #define netdev_alloc_pcpu_stats(type)					\
2287 	__netdev_alloc_pcpu_stats(type, GFP_KERNEL)
2288 
2289 enum netdev_lag_tx_type {
2290 	NETDEV_LAG_TX_TYPE_UNKNOWN,
2291 	NETDEV_LAG_TX_TYPE_RANDOM,
2292 	NETDEV_LAG_TX_TYPE_BROADCAST,
2293 	NETDEV_LAG_TX_TYPE_ROUNDROBIN,
2294 	NETDEV_LAG_TX_TYPE_ACTIVEBACKUP,
2295 	NETDEV_LAG_TX_TYPE_HASH,
2296 };
2297 
2298 struct netdev_lag_upper_info {
2299 	enum netdev_lag_tx_type tx_type;
2300 };
2301 
2302 struct netdev_lag_lower_state_info {
2303 	u8 link_up : 1,
2304 	   tx_enabled : 1;
2305 };
2306 
2307 #include <linux/notifier.h>
2308 
2309 /* netdevice notifier chain. Please remember to update the rtnetlink
2310  * notification exclusion list in rtnetlink_event() when adding new
2311  * types.
2312  */
2313 #define NETDEV_UP	0x0001	/* For now you can't veto a device up/down */
2314 #define NETDEV_DOWN	0x0002
2315 #define NETDEV_REBOOT	0x0003	/* Tell a protocol stack a network interface
2316 				   detected a hardware crash and restarted
2317 				   - we can use this eg to kick tcp sessions
2318 				   once done */
2319 #define NETDEV_CHANGE	0x0004	/* Notify device state change */
2320 #define NETDEV_REGISTER 0x0005
2321 #define NETDEV_UNREGISTER	0x0006
2322 #define NETDEV_CHANGEMTU	0x0007 /* notify after mtu change happened */
2323 #define NETDEV_CHANGEADDR	0x0008
2324 #define NETDEV_GOING_DOWN	0x0009
2325 #define NETDEV_CHANGENAME	0x000A
2326 #define NETDEV_FEAT_CHANGE	0x000B
2327 #define NETDEV_BONDING_FAILOVER 0x000C
2328 #define NETDEV_PRE_UP		0x000D
2329 #define NETDEV_PRE_TYPE_CHANGE	0x000E
2330 #define NETDEV_POST_TYPE_CHANGE	0x000F
2331 #define NETDEV_POST_INIT	0x0010
2332 #define NETDEV_UNREGISTER_FINAL 0x0011
2333 #define NETDEV_RELEASE		0x0012
2334 #define NETDEV_NOTIFY_PEERS	0x0013
2335 #define NETDEV_JOIN		0x0014
2336 #define NETDEV_CHANGEUPPER	0x0015
2337 #define NETDEV_RESEND_IGMP	0x0016
2338 #define NETDEV_PRECHANGEMTU	0x0017 /* notify before mtu change happened */
2339 #define NETDEV_CHANGEINFODATA	0x0018
2340 #define NETDEV_BONDING_INFO	0x0019
2341 #define NETDEV_PRECHANGEUPPER	0x001A
2342 #define NETDEV_CHANGELOWERSTATE	0x001B
2343 #define NETDEV_UDP_TUNNEL_PUSH_INFO	0x001C
2344 #define NETDEV_UDP_TUNNEL_DROP_INFO	0x001D
2345 #define NETDEV_CHANGE_TX_QUEUE_LEN	0x001E
2346 
2347 int register_netdevice_notifier(struct notifier_block *nb);
2348 int unregister_netdevice_notifier(struct notifier_block *nb);
2349 
2350 struct netdev_notifier_info {
2351 	struct net_device	*dev;
2352 	struct netlink_ext_ack	*extack;
2353 };
2354 
2355 struct netdev_notifier_change_info {
2356 	struct netdev_notifier_info info; /* must be first */
2357 	unsigned int flags_changed;
2358 };
2359 
2360 struct netdev_notifier_changeupper_info {
2361 	struct netdev_notifier_info info; /* must be first */
2362 	struct net_device *upper_dev; /* new upper dev */
2363 	bool master; /* is upper dev master */
2364 	bool linking; /* is the notification for link or unlink */
2365 	void *upper_info; /* upper dev info */
2366 };
2367 
2368 struct netdev_notifier_changelowerstate_info {
2369 	struct netdev_notifier_info info; /* must be first */
2370 	void *lower_state_info; /* is lower dev state */
2371 };
2372 
2373 static inline void netdev_notifier_info_init(struct netdev_notifier_info *info,
2374 					     struct net_device *dev)
2375 {
2376 	info->dev = dev;
2377 	info->extack = NULL;
2378 }
2379 
2380 static inline struct net_device *
2381 netdev_notifier_info_to_dev(const struct netdev_notifier_info *info)
2382 {
2383 	return info->dev;
2384 }
2385 
2386 static inline struct netlink_ext_ack *
2387 netdev_notifier_info_to_extack(const struct netdev_notifier_info *info)
2388 {
2389 	return info->extack;
2390 }
2391 
2392 int call_netdevice_notifiers(unsigned long val, struct net_device *dev);
2393 
2394 
2395 extern rwlock_t				dev_base_lock;		/* Device list lock */
2396 
2397 #define for_each_netdev(net, d)		\
2398 		list_for_each_entry(d, &(net)->dev_base_head, dev_list)
2399 #define for_each_netdev_reverse(net, d)	\
2400 		list_for_each_entry_reverse(d, &(net)->dev_base_head, dev_list)
2401 #define for_each_netdev_rcu(net, d)		\
2402 		list_for_each_entry_rcu(d, &(net)->dev_base_head, dev_list)
2403 #define for_each_netdev_safe(net, d, n)	\
2404 		list_for_each_entry_safe(d, n, &(net)->dev_base_head, dev_list)
2405 #define for_each_netdev_continue(net, d)		\
2406 		list_for_each_entry_continue(d, &(net)->dev_base_head, dev_list)
2407 #define for_each_netdev_continue_rcu(net, d)		\
2408 	list_for_each_entry_continue_rcu(d, &(net)->dev_base_head, dev_list)
2409 #define for_each_netdev_in_bond_rcu(bond, slave)	\
2410 		for_each_netdev_rcu(&init_net, slave)	\
2411 			if (netdev_master_upper_dev_get_rcu(slave) == (bond))
2412 #define net_device_entry(lh)	list_entry(lh, struct net_device, dev_list)
2413 
2414 static inline struct net_device *next_net_device(struct net_device *dev)
2415 {
2416 	struct list_head *lh;
2417 	struct net *net;
2418 
2419 	net = dev_net(dev);
2420 	lh = dev->dev_list.next;
2421 	return lh == &net->dev_base_head ? NULL : net_device_entry(lh);
2422 }
2423 
2424 static inline struct net_device *next_net_device_rcu(struct net_device *dev)
2425 {
2426 	struct list_head *lh;
2427 	struct net *net;
2428 
2429 	net = dev_net(dev);
2430 	lh = rcu_dereference(list_next_rcu(&dev->dev_list));
2431 	return lh == &net->dev_base_head ? NULL : net_device_entry(lh);
2432 }
2433 
2434 static inline struct net_device *first_net_device(struct net *net)
2435 {
2436 	return list_empty(&net->dev_base_head) ? NULL :
2437 		net_device_entry(net->dev_base_head.next);
2438 }
2439 
2440 static inline struct net_device *first_net_device_rcu(struct net *net)
2441 {
2442 	struct list_head *lh = rcu_dereference(list_next_rcu(&net->dev_base_head));
2443 
2444 	return lh == &net->dev_base_head ? NULL : net_device_entry(lh);
2445 }
2446 
2447 int netdev_boot_setup_check(struct net_device *dev);
2448 unsigned long netdev_boot_base(const char *prefix, int unit);
2449 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
2450 				       const char *hwaddr);
2451 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type);
2452 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type);
2453 void dev_add_pack(struct packet_type *pt);
2454 void dev_remove_pack(struct packet_type *pt);
2455 void __dev_remove_pack(struct packet_type *pt);
2456 void dev_add_offload(struct packet_offload *po);
2457 void dev_remove_offload(struct packet_offload *po);
2458 
2459 int dev_get_iflink(const struct net_device *dev);
2460 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb);
2461 struct net_device *__dev_get_by_flags(struct net *net, unsigned short flags,
2462 				      unsigned short mask);
2463 struct net_device *dev_get_by_name(struct net *net, const char *name);
2464 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name);
2465 struct net_device *__dev_get_by_name(struct net *net, const char *name);
2466 int dev_alloc_name(struct net_device *dev, const char *name);
2467 int dev_open(struct net_device *dev);
2468 void dev_close(struct net_device *dev);
2469 void dev_close_many(struct list_head *head, bool unlink);
2470 void dev_disable_lro(struct net_device *dev);
2471 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *newskb);
2472 int dev_queue_xmit(struct sk_buff *skb);
2473 int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv);
2474 int register_netdevice(struct net_device *dev);
2475 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head);
2476 void unregister_netdevice_many(struct list_head *head);
2477 static inline void unregister_netdevice(struct net_device *dev)
2478 {
2479 	unregister_netdevice_queue(dev, NULL);
2480 }
2481 
2482 int netdev_refcnt_read(const struct net_device *dev);
2483 void free_netdev(struct net_device *dev);
2484 void netdev_freemem(struct net_device *dev);
2485 void synchronize_net(void);
2486 int init_dummy_netdev(struct net_device *dev);
2487 
2488 DECLARE_PER_CPU(int, xmit_recursion);
2489 #define XMIT_RECURSION_LIMIT	10
2490 
2491 static inline int dev_recursion_level(void)
2492 {
2493 	return this_cpu_read(xmit_recursion);
2494 }
2495 
2496 struct net_device *dev_get_by_index(struct net *net, int ifindex);
2497 struct net_device *__dev_get_by_index(struct net *net, int ifindex);
2498 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex);
2499 struct net_device *dev_get_by_napi_id(unsigned int napi_id);
2500 int netdev_get_name(struct net *net, char *name, int ifindex);
2501 int dev_restart(struct net_device *dev);
2502 int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb);
2503 
2504 static inline unsigned int skb_gro_offset(const struct sk_buff *skb)
2505 {
2506 	return NAPI_GRO_CB(skb)->data_offset;
2507 }
2508 
2509 static inline unsigned int skb_gro_len(const struct sk_buff *skb)
2510 {
2511 	return skb->len - NAPI_GRO_CB(skb)->data_offset;
2512 }
2513 
2514 static inline void skb_gro_pull(struct sk_buff *skb, unsigned int len)
2515 {
2516 	NAPI_GRO_CB(skb)->data_offset += len;
2517 }
2518 
2519 static inline void *skb_gro_header_fast(struct sk_buff *skb,
2520 					unsigned int offset)
2521 {
2522 	return NAPI_GRO_CB(skb)->frag0 + offset;
2523 }
2524 
2525 static inline int skb_gro_header_hard(struct sk_buff *skb, unsigned int hlen)
2526 {
2527 	return NAPI_GRO_CB(skb)->frag0_len < hlen;
2528 }
2529 
2530 static inline void skb_gro_frag0_invalidate(struct sk_buff *skb)
2531 {
2532 	NAPI_GRO_CB(skb)->frag0 = NULL;
2533 	NAPI_GRO_CB(skb)->frag0_len = 0;
2534 }
2535 
2536 static inline void *skb_gro_header_slow(struct sk_buff *skb, unsigned int hlen,
2537 					unsigned int offset)
2538 {
2539 	if (!pskb_may_pull(skb, hlen))
2540 		return NULL;
2541 
2542 	skb_gro_frag0_invalidate(skb);
2543 	return skb->data + offset;
2544 }
2545 
2546 static inline void *skb_gro_network_header(struct sk_buff *skb)
2547 {
2548 	return (NAPI_GRO_CB(skb)->frag0 ?: skb->data) +
2549 	       skb_network_offset(skb);
2550 }
2551 
2552 static inline void skb_gro_postpull_rcsum(struct sk_buff *skb,
2553 					const void *start, unsigned int len)
2554 {
2555 	if (NAPI_GRO_CB(skb)->csum_valid)
2556 		NAPI_GRO_CB(skb)->csum = csum_sub(NAPI_GRO_CB(skb)->csum,
2557 						  csum_partial(start, len, 0));
2558 }
2559 
2560 /* GRO checksum functions. These are logical equivalents of the normal
2561  * checksum functions (in skbuff.h) except that they operate on the GRO
2562  * offsets and fields in sk_buff.
2563  */
2564 
2565 __sum16 __skb_gro_checksum_complete(struct sk_buff *skb);
2566 
2567 static inline bool skb_at_gro_remcsum_start(struct sk_buff *skb)
2568 {
2569 	return (NAPI_GRO_CB(skb)->gro_remcsum_start == skb_gro_offset(skb));
2570 }
2571 
2572 static inline bool __skb_gro_checksum_validate_needed(struct sk_buff *skb,
2573 						      bool zero_okay,
2574 						      __sum16 check)
2575 {
2576 	return ((skb->ip_summed != CHECKSUM_PARTIAL ||
2577 		skb_checksum_start_offset(skb) <
2578 		 skb_gro_offset(skb)) &&
2579 		!skb_at_gro_remcsum_start(skb) &&
2580 		NAPI_GRO_CB(skb)->csum_cnt == 0 &&
2581 		(!zero_okay || check));
2582 }
2583 
2584 static inline __sum16 __skb_gro_checksum_validate_complete(struct sk_buff *skb,
2585 							   __wsum psum)
2586 {
2587 	if (NAPI_GRO_CB(skb)->csum_valid &&
2588 	    !csum_fold(csum_add(psum, NAPI_GRO_CB(skb)->csum)))
2589 		return 0;
2590 
2591 	NAPI_GRO_CB(skb)->csum = psum;
2592 
2593 	return __skb_gro_checksum_complete(skb);
2594 }
2595 
2596 static inline void skb_gro_incr_csum_unnecessary(struct sk_buff *skb)
2597 {
2598 	if (NAPI_GRO_CB(skb)->csum_cnt > 0) {
2599 		/* Consume a checksum from CHECKSUM_UNNECESSARY */
2600 		NAPI_GRO_CB(skb)->csum_cnt--;
2601 	} else {
2602 		/* Update skb for CHECKSUM_UNNECESSARY and csum_level when we
2603 		 * verified a new top level checksum or an encapsulated one
2604 		 * during GRO. This saves work if we fallback to normal path.
2605 		 */
2606 		__skb_incr_checksum_unnecessary(skb);
2607 	}
2608 }
2609 
2610 #define __skb_gro_checksum_validate(skb, proto, zero_okay, check,	\
2611 				    compute_pseudo)			\
2612 ({									\
2613 	__sum16 __ret = 0;						\
2614 	if (__skb_gro_checksum_validate_needed(skb, zero_okay, check))	\
2615 		__ret = __skb_gro_checksum_validate_complete(skb,	\
2616 				compute_pseudo(skb, proto));		\
2617 	if (!__ret)							\
2618 		skb_gro_incr_csum_unnecessary(skb);			\
2619 	__ret;								\
2620 })
2621 
2622 #define skb_gro_checksum_validate(skb, proto, compute_pseudo)		\
2623 	__skb_gro_checksum_validate(skb, proto, false, 0, compute_pseudo)
2624 
2625 #define skb_gro_checksum_validate_zero_check(skb, proto, check,		\
2626 					     compute_pseudo)		\
2627 	__skb_gro_checksum_validate(skb, proto, true, check, compute_pseudo)
2628 
2629 #define skb_gro_checksum_simple_validate(skb)				\
2630 	__skb_gro_checksum_validate(skb, 0, false, 0, null_compute_pseudo)
2631 
2632 static inline bool __skb_gro_checksum_convert_check(struct sk_buff *skb)
2633 {
2634 	return (NAPI_GRO_CB(skb)->csum_cnt == 0 &&
2635 		!NAPI_GRO_CB(skb)->csum_valid);
2636 }
2637 
2638 static inline void __skb_gro_checksum_convert(struct sk_buff *skb,
2639 					      __sum16 check, __wsum pseudo)
2640 {
2641 	NAPI_GRO_CB(skb)->csum = ~pseudo;
2642 	NAPI_GRO_CB(skb)->csum_valid = 1;
2643 }
2644 
2645 #define skb_gro_checksum_try_convert(skb, proto, check, compute_pseudo)	\
2646 do {									\
2647 	if (__skb_gro_checksum_convert_check(skb))			\
2648 		__skb_gro_checksum_convert(skb, check,			\
2649 					   compute_pseudo(skb, proto));	\
2650 } while (0)
2651 
2652 struct gro_remcsum {
2653 	int offset;
2654 	__wsum delta;
2655 };
2656 
2657 static inline void skb_gro_remcsum_init(struct gro_remcsum *grc)
2658 {
2659 	grc->offset = 0;
2660 	grc->delta = 0;
2661 }
2662 
2663 static inline void *skb_gro_remcsum_process(struct sk_buff *skb, void *ptr,
2664 					    unsigned int off, size_t hdrlen,
2665 					    int start, int offset,
2666 					    struct gro_remcsum *grc,
2667 					    bool nopartial)
2668 {
2669 	__wsum delta;
2670 	size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start);
2671 
2672 	BUG_ON(!NAPI_GRO_CB(skb)->csum_valid);
2673 
2674 	if (!nopartial) {
2675 		NAPI_GRO_CB(skb)->gro_remcsum_start = off + hdrlen + start;
2676 		return ptr;
2677 	}
2678 
2679 	ptr = skb_gro_header_fast(skb, off);
2680 	if (skb_gro_header_hard(skb, off + plen)) {
2681 		ptr = skb_gro_header_slow(skb, off + plen, off);
2682 		if (!ptr)
2683 			return NULL;
2684 	}
2685 
2686 	delta = remcsum_adjust(ptr + hdrlen, NAPI_GRO_CB(skb)->csum,
2687 			       start, offset);
2688 
2689 	/* Adjust skb->csum since we changed the packet */
2690 	NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta);
2691 
2692 	grc->offset = off + hdrlen + offset;
2693 	grc->delta = delta;
2694 
2695 	return ptr;
2696 }
2697 
2698 static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb,
2699 					   struct gro_remcsum *grc)
2700 {
2701 	void *ptr;
2702 	size_t plen = grc->offset + sizeof(u16);
2703 
2704 	if (!grc->delta)
2705 		return;
2706 
2707 	ptr = skb_gro_header_fast(skb, grc->offset);
2708 	if (skb_gro_header_hard(skb, grc->offset + sizeof(u16))) {
2709 		ptr = skb_gro_header_slow(skb, plen, grc->offset);
2710 		if (!ptr)
2711 			return;
2712 	}
2713 
2714 	remcsum_unadjust((__sum16 *)ptr, grc->delta);
2715 }
2716 
2717 #ifdef CONFIG_XFRM_OFFLOAD
2718 static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff **pp, int flush)
2719 {
2720 	if (PTR_ERR(pp) != -EINPROGRESS)
2721 		NAPI_GRO_CB(skb)->flush |= flush;
2722 }
2723 #else
2724 static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff **pp, int flush)
2725 {
2726 	NAPI_GRO_CB(skb)->flush |= flush;
2727 }
2728 #endif
2729 
2730 static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev,
2731 				  unsigned short type,
2732 				  const void *daddr, const void *saddr,
2733 				  unsigned int len)
2734 {
2735 	if (!dev->header_ops || !dev->header_ops->create)
2736 		return 0;
2737 
2738 	return dev->header_ops->create(skb, dev, type, daddr, saddr, len);
2739 }
2740 
2741 static inline int dev_parse_header(const struct sk_buff *skb,
2742 				   unsigned char *haddr)
2743 {
2744 	const struct net_device *dev = skb->dev;
2745 
2746 	if (!dev->header_ops || !dev->header_ops->parse)
2747 		return 0;
2748 	return dev->header_ops->parse(skb, haddr);
2749 }
2750 
2751 /* ll_header must have at least hard_header_len allocated */
2752 static inline bool dev_validate_header(const struct net_device *dev,
2753 				       char *ll_header, int len)
2754 {
2755 	if (likely(len >= dev->hard_header_len))
2756 		return true;
2757 	if (len < dev->min_header_len)
2758 		return false;
2759 
2760 	if (capable(CAP_SYS_RAWIO)) {
2761 		memset(ll_header + len, 0, dev->hard_header_len - len);
2762 		return true;
2763 	}
2764 
2765 	if (dev->header_ops && dev->header_ops->validate)
2766 		return dev->header_ops->validate(ll_header, len);
2767 
2768 	return false;
2769 }
2770 
2771 typedef int gifconf_func_t(struct net_device * dev, char __user * bufptr,
2772 			   int len, int size);
2773 int register_gifconf(unsigned int family, gifconf_func_t *gifconf);
2774 static inline int unregister_gifconf(unsigned int family)
2775 {
2776 	return register_gifconf(family, NULL);
2777 }
2778 
2779 #ifdef CONFIG_NET_FLOW_LIMIT
2780 #define FLOW_LIMIT_HISTORY	(1 << 7)  /* must be ^2 and !overflow buckets */
2781 struct sd_flow_limit {
2782 	u64			count;
2783 	unsigned int		num_buckets;
2784 	unsigned int		history_head;
2785 	u16			history[FLOW_LIMIT_HISTORY];
2786 	u8			buckets[];
2787 };
2788 
2789 extern int netdev_flow_limit_table_len;
2790 #endif /* CONFIG_NET_FLOW_LIMIT */
2791 
2792 /*
2793  * Incoming packets are placed on per-CPU queues
2794  */
2795 struct softnet_data {
2796 	struct list_head	poll_list;
2797 	struct sk_buff_head	process_queue;
2798 
2799 	/* stats */
2800 	unsigned int		processed;
2801 	unsigned int		time_squeeze;
2802 	unsigned int		received_rps;
2803 #ifdef CONFIG_RPS
2804 	struct softnet_data	*rps_ipi_list;
2805 #endif
2806 #ifdef CONFIG_NET_FLOW_LIMIT
2807 	struct sd_flow_limit __rcu *flow_limit;
2808 #endif
2809 	struct Qdisc		*output_queue;
2810 	struct Qdisc		**output_queue_tailp;
2811 	struct sk_buff		*completion_queue;
2812 #ifdef CONFIG_XFRM_OFFLOAD
2813 	struct sk_buff_head	xfrm_backlog;
2814 #endif
2815 #ifdef CONFIG_RPS
2816 	/* input_queue_head should be written by cpu owning this struct,
2817 	 * and only read by other cpus. Worth using a cache line.
2818 	 */
2819 	unsigned int		input_queue_head ____cacheline_aligned_in_smp;
2820 
2821 	/* Elements below can be accessed between CPUs for RPS/RFS */
2822 	call_single_data_t	csd ____cacheline_aligned_in_smp;
2823 	struct softnet_data	*rps_ipi_next;
2824 	unsigned int		cpu;
2825 	unsigned int		input_queue_tail;
2826 #endif
2827 	unsigned int		dropped;
2828 	struct sk_buff_head	input_pkt_queue;
2829 	struct napi_struct	backlog;
2830 
2831 };
2832 
2833 static inline void input_queue_head_incr(struct softnet_data *sd)
2834 {
2835 #ifdef CONFIG_RPS
2836 	sd->input_queue_head++;
2837 #endif
2838 }
2839 
2840 static inline void input_queue_tail_incr_save(struct softnet_data *sd,
2841 					      unsigned int *qtail)
2842 {
2843 #ifdef CONFIG_RPS
2844 	*qtail = ++sd->input_queue_tail;
2845 #endif
2846 }
2847 
2848 DECLARE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
2849 
2850 void __netif_schedule(struct Qdisc *q);
2851 void netif_schedule_queue(struct netdev_queue *txq);
2852 
2853 static inline void netif_tx_schedule_all(struct net_device *dev)
2854 {
2855 	unsigned int i;
2856 
2857 	for (i = 0; i < dev->num_tx_queues; i++)
2858 		netif_schedule_queue(netdev_get_tx_queue(dev, i));
2859 }
2860 
2861 static __always_inline void netif_tx_start_queue(struct netdev_queue *dev_queue)
2862 {
2863 	clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state);
2864 }
2865 
2866 /**
2867  *	netif_start_queue - allow transmit
2868  *	@dev: network device
2869  *
2870  *	Allow upper layers to call the device hard_start_xmit routine.
2871  */
2872 static inline void netif_start_queue(struct net_device *dev)
2873 {
2874 	netif_tx_start_queue(netdev_get_tx_queue(dev, 0));
2875 }
2876 
2877 static inline void netif_tx_start_all_queues(struct net_device *dev)
2878 {
2879 	unsigned int i;
2880 
2881 	for (i = 0; i < dev->num_tx_queues; i++) {
2882 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
2883 		netif_tx_start_queue(txq);
2884 	}
2885 }
2886 
2887 void netif_tx_wake_queue(struct netdev_queue *dev_queue);
2888 
2889 /**
2890  *	netif_wake_queue - restart transmit
2891  *	@dev: network device
2892  *
2893  *	Allow upper layers to call the device hard_start_xmit routine.
2894  *	Used for flow control when transmit resources are available.
2895  */
2896 static inline void netif_wake_queue(struct net_device *dev)
2897 {
2898 	netif_tx_wake_queue(netdev_get_tx_queue(dev, 0));
2899 }
2900 
2901 static inline void netif_tx_wake_all_queues(struct net_device *dev)
2902 {
2903 	unsigned int i;
2904 
2905 	for (i = 0; i < dev->num_tx_queues; i++) {
2906 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
2907 		netif_tx_wake_queue(txq);
2908 	}
2909 }
2910 
2911 static __always_inline void netif_tx_stop_queue(struct netdev_queue *dev_queue)
2912 {
2913 	set_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state);
2914 }
2915 
2916 /**
2917  *	netif_stop_queue - stop transmitted packets
2918  *	@dev: network device
2919  *
2920  *	Stop upper layers calling the device hard_start_xmit routine.
2921  *	Used for flow control when transmit resources are unavailable.
2922  */
2923 static inline void netif_stop_queue(struct net_device *dev)
2924 {
2925 	netif_tx_stop_queue(netdev_get_tx_queue(dev, 0));
2926 }
2927 
2928 void netif_tx_stop_all_queues(struct net_device *dev);
2929 
2930 static inline bool netif_tx_queue_stopped(const struct netdev_queue *dev_queue)
2931 {
2932 	return test_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state);
2933 }
2934 
2935 /**
2936  *	netif_queue_stopped - test if transmit queue is flowblocked
2937  *	@dev: network device
2938  *
2939  *	Test if transmit queue on device is currently unable to send.
2940  */
2941 static inline bool netif_queue_stopped(const struct net_device *dev)
2942 {
2943 	return netif_tx_queue_stopped(netdev_get_tx_queue(dev, 0));
2944 }
2945 
2946 static inline bool netif_xmit_stopped(const struct netdev_queue *dev_queue)
2947 {
2948 	return dev_queue->state & QUEUE_STATE_ANY_XOFF;
2949 }
2950 
2951 static inline bool
2952 netif_xmit_frozen_or_stopped(const struct netdev_queue *dev_queue)
2953 {
2954 	return dev_queue->state & QUEUE_STATE_ANY_XOFF_OR_FROZEN;
2955 }
2956 
2957 static inline bool
2958 netif_xmit_frozen_or_drv_stopped(const struct netdev_queue *dev_queue)
2959 {
2960 	return dev_queue->state & QUEUE_STATE_DRV_XOFF_OR_FROZEN;
2961 }
2962 
2963 /**
2964  *	netdev_txq_bql_enqueue_prefetchw - prefetch bql data for write
2965  *	@dev_queue: pointer to transmit queue
2966  *
2967  * BQL enabled drivers might use this helper in their ndo_start_xmit(),
2968  * to give appropriate hint to the CPU.
2969  */
2970 static inline void netdev_txq_bql_enqueue_prefetchw(struct netdev_queue *dev_queue)
2971 {
2972 #ifdef CONFIG_BQL
2973 	prefetchw(&dev_queue->dql.num_queued);
2974 #endif
2975 }
2976 
2977 /**
2978  *	netdev_txq_bql_complete_prefetchw - prefetch bql data for write
2979  *	@dev_queue: pointer to transmit queue
2980  *
2981  * BQL enabled drivers might use this helper in their TX completion path,
2982  * to give appropriate hint to the CPU.
2983  */
2984 static inline void netdev_txq_bql_complete_prefetchw(struct netdev_queue *dev_queue)
2985 {
2986 #ifdef CONFIG_BQL
2987 	prefetchw(&dev_queue->dql.limit);
2988 #endif
2989 }
2990 
2991 static inline void netdev_tx_sent_queue(struct netdev_queue *dev_queue,
2992 					unsigned int bytes)
2993 {
2994 #ifdef CONFIG_BQL
2995 	dql_queued(&dev_queue->dql, bytes);
2996 
2997 	if (likely(dql_avail(&dev_queue->dql) >= 0))
2998 		return;
2999 
3000 	set_bit(__QUEUE_STATE_STACK_XOFF, &dev_queue->state);
3001 
3002 	/*
3003 	 * The XOFF flag must be set before checking the dql_avail below,
3004 	 * because in netdev_tx_completed_queue we update the dql_completed
3005 	 * before checking the XOFF flag.
3006 	 */
3007 	smp_mb();
3008 
3009 	/* check again in case another CPU has just made room avail */
3010 	if (unlikely(dql_avail(&dev_queue->dql) >= 0))
3011 		clear_bit(__QUEUE_STATE_STACK_XOFF, &dev_queue->state);
3012 #endif
3013 }
3014 
3015 /**
3016  * 	netdev_sent_queue - report the number of bytes queued to hardware
3017  * 	@dev: network device
3018  * 	@bytes: number of bytes queued to the hardware device queue
3019  *
3020  * 	Report the number of bytes queued for sending/completion to the network
3021  * 	device hardware queue. @bytes should be a good approximation and should
3022  * 	exactly match netdev_completed_queue() @bytes
3023  */
3024 static inline void netdev_sent_queue(struct net_device *dev, unsigned int bytes)
3025 {
3026 	netdev_tx_sent_queue(netdev_get_tx_queue(dev, 0), bytes);
3027 }
3028 
3029 static inline void netdev_tx_completed_queue(struct netdev_queue *dev_queue,
3030 					     unsigned int pkts, unsigned int bytes)
3031 {
3032 #ifdef CONFIG_BQL
3033 	if (unlikely(!bytes))
3034 		return;
3035 
3036 	dql_completed(&dev_queue->dql, bytes);
3037 
3038 	/*
3039 	 * Without the memory barrier there is a small possiblity that
3040 	 * netdev_tx_sent_queue will miss the update and cause the queue to
3041 	 * be stopped forever
3042 	 */
3043 	smp_mb();
3044 
3045 	if (dql_avail(&dev_queue->dql) < 0)
3046 		return;
3047 
3048 	if (test_and_clear_bit(__QUEUE_STATE_STACK_XOFF, &dev_queue->state))
3049 		netif_schedule_queue(dev_queue);
3050 #endif
3051 }
3052 
3053 /**
3054  * 	netdev_completed_queue - report bytes and packets completed by device
3055  * 	@dev: network device
3056  * 	@pkts: actual number of packets sent over the medium
3057  * 	@bytes: actual number of bytes sent over the medium
3058  *
3059  * 	Report the number of bytes and packets transmitted by the network device
3060  * 	hardware queue over the physical medium, @bytes must exactly match the
3061  * 	@bytes amount passed to netdev_sent_queue()
3062  */
3063 static inline void netdev_completed_queue(struct net_device *dev,
3064 					  unsigned int pkts, unsigned int bytes)
3065 {
3066 	netdev_tx_completed_queue(netdev_get_tx_queue(dev, 0), pkts, bytes);
3067 }
3068 
3069 static inline void netdev_tx_reset_queue(struct netdev_queue *q)
3070 {
3071 #ifdef CONFIG_BQL
3072 	clear_bit(__QUEUE_STATE_STACK_XOFF, &q->state);
3073 	dql_reset(&q->dql);
3074 #endif
3075 }
3076 
3077 /**
3078  * 	netdev_reset_queue - reset the packets and bytes count of a network device
3079  * 	@dev_queue: network device
3080  *
3081  * 	Reset the bytes and packet count of a network device and clear the
3082  * 	software flow control OFF bit for this network device
3083  */
3084 static inline void netdev_reset_queue(struct net_device *dev_queue)
3085 {
3086 	netdev_tx_reset_queue(netdev_get_tx_queue(dev_queue, 0));
3087 }
3088 
3089 /**
3090  * 	netdev_cap_txqueue - check if selected tx queue exceeds device queues
3091  * 	@dev: network device
3092  * 	@queue_index: given tx queue index
3093  *
3094  * 	Returns 0 if given tx queue index >= number of device tx queues,
3095  * 	otherwise returns the originally passed tx queue index.
3096  */
3097 static inline u16 netdev_cap_txqueue(struct net_device *dev, u16 queue_index)
3098 {
3099 	if (unlikely(queue_index >= dev->real_num_tx_queues)) {
3100 		net_warn_ratelimited("%s selects TX queue %d, but real number of TX queues is %d\n",
3101 				     dev->name, queue_index,
3102 				     dev->real_num_tx_queues);
3103 		return 0;
3104 	}
3105 
3106 	return queue_index;
3107 }
3108 
3109 /**
3110  *	netif_running - test if up
3111  *	@dev: network device
3112  *
3113  *	Test if the device has been brought up.
3114  */
3115 static inline bool netif_running(const struct net_device *dev)
3116 {
3117 	return test_bit(__LINK_STATE_START, &dev->state);
3118 }
3119 
3120 /*
3121  * Routines to manage the subqueues on a device.  We only need start,
3122  * stop, and a check if it's stopped.  All other device management is
3123  * done at the overall netdevice level.
3124  * Also test the device if we're multiqueue.
3125  */
3126 
3127 /**
3128  *	netif_start_subqueue - allow sending packets on subqueue
3129  *	@dev: network device
3130  *	@queue_index: sub queue index
3131  *
3132  * Start individual transmit queue of a device with multiple transmit queues.
3133  */
3134 static inline void netif_start_subqueue(struct net_device *dev, u16 queue_index)
3135 {
3136 	struct netdev_queue *txq = netdev_get_tx_queue(dev, queue_index);
3137 
3138 	netif_tx_start_queue(txq);
3139 }
3140 
3141 /**
3142  *	netif_stop_subqueue - stop sending packets on subqueue
3143  *	@dev: network device
3144  *	@queue_index: sub queue index
3145  *
3146  * Stop individual transmit queue of a device with multiple transmit queues.
3147  */
3148 static inline void netif_stop_subqueue(struct net_device *dev, u16 queue_index)
3149 {
3150 	struct netdev_queue *txq = netdev_get_tx_queue(dev, queue_index);
3151 	netif_tx_stop_queue(txq);
3152 }
3153 
3154 /**
3155  *	netif_subqueue_stopped - test status of subqueue
3156  *	@dev: network device
3157  *	@queue_index: sub queue index
3158  *
3159  * Check individual transmit queue of a device with multiple transmit queues.
3160  */
3161 static inline bool __netif_subqueue_stopped(const struct net_device *dev,
3162 					    u16 queue_index)
3163 {
3164 	struct netdev_queue *txq = netdev_get_tx_queue(dev, queue_index);
3165 
3166 	return netif_tx_queue_stopped(txq);
3167 }
3168 
3169 static inline bool netif_subqueue_stopped(const struct net_device *dev,
3170 					  struct sk_buff *skb)
3171 {
3172 	return __netif_subqueue_stopped(dev, skb_get_queue_mapping(skb));
3173 }
3174 
3175 /**
3176  *	netif_wake_subqueue - allow sending packets on subqueue
3177  *	@dev: network device
3178  *	@queue_index: sub queue index
3179  *
3180  * Resume individual transmit queue of a device with multiple transmit queues.
3181  */
3182 static inline void netif_wake_subqueue(struct net_device *dev, u16 queue_index)
3183 {
3184 	struct netdev_queue *txq = netdev_get_tx_queue(dev, queue_index);
3185 
3186 	netif_tx_wake_queue(txq);
3187 }
3188 
3189 #ifdef CONFIG_XPS
3190 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
3191 			u16 index);
3192 #else
3193 static inline int netif_set_xps_queue(struct net_device *dev,
3194 				      const struct cpumask *mask,
3195 				      u16 index)
3196 {
3197 	return 0;
3198 }
3199 #endif
3200 
3201 u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb,
3202 		  unsigned int num_tx_queues);
3203 
3204 /*
3205  * Returns a Tx hash for the given packet when dev->real_num_tx_queues is used
3206  * as a distribution range limit for the returned value.
3207  */
3208 static inline u16 skb_tx_hash(const struct net_device *dev,
3209 			      struct sk_buff *skb)
3210 {
3211 	return __skb_tx_hash(dev, skb, dev->real_num_tx_queues);
3212 }
3213 
3214 /**
3215  *	netif_is_multiqueue - test if device has multiple transmit queues
3216  *	@dev: network device
3217  *
3218  * Check if device has multiple transmit queues
3219  */
3220 static inline bool netif_is_multiqueue(const struct net_device *dev)
3221 {
3222 	return dev->num_tx_queues > 1;
3223 }
3224 
3225 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq);
3226 
3227 #ifdef CONFIG_SYSFS
3228 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq);
3229 #else
3230 static inline int netif_set_real_num_rx_queues(struct net_device *dev,
3231 						unsigned int rxq)
3232 {
3233 	return 0;
3234 }
3235 #endif
3236 
3237 static inline struct netdev_rx_queue *
3238 __netif_get_rx_queue(struct net_device *dev, unsigned int rxq)
3239 {
3240 	return dev->_rx + rxq;
3241 }
3242 
3243 #ifdef CONFIG_SYSFS
3244 static inline unsigned int get_netdev_rx_queue_index(
3245 		struct netdev_rx_queue *queue)
3246 {
3247 	struct net_device *dev = queue->dev;
3248 	int index = queue - dev->_rx;
3249 
3250 	BUG_ON(index >= dev->num_rx_queues);
3251 	return index;
3252 }
3253 #endif
3254 
3255 #define DEFAULT_MAX_NUM_RSS_QUEUES	(8)
3256 int netif_get_num_default_rss_queues(void);
3257 
3258 enum skb_free_reason {
3259 	SKB_REASON_CONSUMED,
3260 	SKB_REASON_DROPPED,
3261 };
3262 
3263 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason);
3264 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason);
3265 
3266 /*
3267  * It is not allowed to call kfree_skb() or consume_skb() from hardware
3268  * interrupt context or with hardware interrupts being disabled.
3269  * (in_irq() || irqs_disabled())
3270  *
3271  * We provide four helpers that can be used in following contexts :
3272  *
3273  * dev_kfree_skb_irq(skb) when caller drops a packet from irq context,
3274  *  replacing kfree_skb(skb)
3275  *
3276  * dev_consume_skb_irq(skb) when caller consumes a packet from irq context.
3277  *  Typically used in place of consume_skb(skb) in TX completion path
3278  *
3279  * dev_kfree_skb_any(skb) when caller doesn't know its current irq context,
3280  *  replacing kfree_skb(skb)
3281  *
3282  * dev_consume_skb_any(skb) when caller doesn't know its current irq context,
3283  *  and consumed a packet. Used in place of consume_skb(skb)
3284  */
3285 static inline void dev_kfree_skb_irq(struct sk_buff *skb)
3286 {
3287 	__dev_kfree_skb_irq(skb, SKB_REASON_DROPPED);
3288 }
3289 
3290 static inline void dev_consume_skb_irq(struct sk_buff *skb)
3291 {
3292 	__dev_kfree_skb_irq(skb, SKB_REASON_CONSUMED);
3293 }
3294 
3295 static inline void dev_kfree_skb_any(struct sk_buff *skb)
3296 {
3297 	__dev_kfree_skb_any(skb, SKB_REASON_DROPPED);
3298 }
3299 
3300 static inline void dev_consume_skb_any(struct sk_buff *skb)
3301 {
3302 	__dev_kfree_skb_any(skb, SKB_REASON_CONSUMED);
3303 }
3304 
3305 void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog);
3306 int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb);
3307 int netif_rx(struct sk_buff *skb);
3308 int netif_rx_ni(struct sk_buff *skb);
3309 int netif_receive_skb(struct sk_buff *skb);
3310 int netif_receive_skb_core(struct sk_buff *skb);
3311 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb);
3312 void napi_gro_flush(struct napi_struct *napi, bool flush_old);
3313 struct sk_buff *napi_get_frags(struct napi_struct *napi);
3314 gro_result_t napi_gro_frags(struct napi_struct *napi);
3315 struct packet_offload *gro_find_receive_by_type(__be16 type);
3316 struct packet_offload *gro_find_complete_by_type(__be16 type);
3317 
3318 static inline void napi_free_frags(struct napi_struct *napi)
3319 {
3320 	kfree_skb(napi->skb);
3321 	napi->skb = NULL;
3322 }
3323 
3324 bool netdev_is_rx_handler_busy(struct net_device *dev);
3325 int netdev_rx_handler_register(struct net_device *dev,
3326 			       rx_handler_func_t *rx_handler,
3327 			       void *rx_handler_data);
3328 void netdev_rx_handler_unregister(struct net_device *dev);
3329 
3330 bool dev_valid_name(const char *name);
3331 int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr,
3332 		bool *need_copyout);
3333 int dev_ifconf(struct net *net, struct ifconf *, int);
3334 int dev_ethtool(struct net *net, struct ifreq *);
3335 unsigned int dev_get_flags(const struct net_device *);
3336 int __dev_change_flags(struct net_device *, unsigned int flags);
3337 int dev_change_flags(struct net_device *, unsigned int);
3338 void __dev_notify_flags(struct net_device *, unsigned int old_flags,
3339 			unsigned int gchanges);
3340 int dev_change_name(struct net_device *, const char *);
3341 int dev_set_alias(struct net_device *, const char *, size_t);
3342 int dev_get_alias(const struct net_device *, char *, size_t);
3343 int dev_change_net_namespace(struct net_device *, struct net *, const char *);
3344 int __dev_set_mtu(struct net_device *, int);
3345 int dev_set_mtu(struct net_device *, int);
3346 int dev_change_tx_queue_len(struct net_device *, unsigned long);
3347 void dev_set_group(struct net_device *, int);
3348 int dev_set_mac_address(struct net_device *, struct sockaddr *);
3349 int dev_change_carrier(struct net_device *, bool new_carrier);
3350 int dev_get_phys_port_id(struct net_device *dev,
3351 			 struct netdev_phys_item_id *ppid);
3352 int dev_get_phys_port_name(struct net_device *dev,
3353 			   char *name, size_t len);
3354 int dev_change_proto_down(struct net_device *dev, bool proto_down);
3355 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again);
3356 struct sk_buff *dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
3357 				    struct netdev_queue *txq, int *ret);
3358 
3359 typedef int (*bpf_op_t)(struct net_device *dev, struct netdev_bpf *bpf);
3360 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
3361 		      int fd, u32 flags);
3362 void __dev_xdp_query(struct net_device *dev, bpf_op_t xdp_op,
3363 		     struct netdev_bpf *xdp);
3364 
3365 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb);
3366 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb);
3367 bool is_skb_forwardable(const struct net_device *dev,
3368 			const struct sk_buff *skb);
3369 
3370 static __always_inline int ____dev_forward_skb(struct net_device *dev,
3371 					       struct sk_buff *skb)
3372 {
3373 	if (skb_orphan_frags(skb, GFP_ATOMIC) ||
3374 	    unlikely(!is_skb_forwardable(dev, skb))) {
3375 		atomic_long_inc(&dev->rx_dropped);
3376 		kfree_skb(skb);
3377 		return NET_RX_DROP;
3378 	}
3379 
3380 	skb_scrub_packet(skb, true);
3381 	skb->priority = 0;
3382 	return 0;
3383 }
3384 
3385 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev);
3386 
3387 extern int		netdev_budget;
3388 extern unsigned int	netdev_budget_usecs;
3389 
3390 /* Called by rtnetlink.c:rtnl_unlock() */
3391 void netdev_run_todo(void);
3392 
3393 /**
3394  *	dev_put - release reference to device
3395  *	@dev: network device
3396  *
3397  * Release reference to device to allow it to be freed.
3398  */
3399 static inline void dev_put(struct net_device *dev)
3400 {
3401 	this_cpu_dec(*dev->pcpu_refcnt);
3402 }
3403 
3404 /**
3405  *	dev_hold - get reference to device
3406  *	@dev: network device
3407  *
3408  * Hold reference to device to keep it from being freed.
3409  */
3410 static inline void dev_hold(struct net_device *dev)
3411 {
3412 	this_cpu_inc(*dev->pcpu_refcnt);
3413 }
3414 
3415 /* Carrier loss detection, dial on demand. The functions netif_carrier_on
3416  * and _off may be called from IRQ context, but it is caller
3417  * who is responsible for serialization of these calls.
3418  *
3419  * The name carrier is inappropriate, these functions should really be
3420  * called netif_lowerlayer_*() because they represent the state of any
3421  * kind of lower layer not just hardware media.
3422  */
3423 
3424 void linkwatch_init_dev(struct net_device *dev);
3425 void linkwatch_fire_event(struct net_device *dev);
3426 void linkwatch_forget_dev(struct net_device *dev);
3427 
3428 /**
3429  *	netif_carrier_ok - test if carrier present
3430  *	@dev: network device
3431  *
3432  * Check if carrier is present on device
3433  */
3434 static inline bool netif_carrier_ok(const struct net_device *dev)
3435 {
3436 	return !test_bit(__LINK_STATE_NOCARRIER, &dev->state);
3437 }
3438 
3439 unsigned long dev_trans_start(struct net_device *dev);
3440 
3441 void __netdev_watchdog_up(struct net_device *dev);
3442 
3443 void netif_carrier_on(struct net_device *dev);
3444 
3445 void netif_carrier_off(struct net_device *dev);
3446 
3447 /**
3448  *	netif_dormant_on - mark device as dormant.
3449  *	@dev: network device
3450  *
3451  * Mark device as dormant (as per RFC2863).
3452  *
3453  * The dormant state indicates that the relevant interface is not
3454  * actually in a condition to pass packets (i.e., it is not 'up') but is
3455  * in a "pending" state, waiting for some external event.  For "on-
3456  * demand" interfaces, this new state identifies the situation where the
3457  * interface is waiting for events to place it in the up state.
3458  */
3459 static inline void netif_dormant_on(struct net_device *dev)
3460 {
3461 	if (!test_and_set_bit(__LINK_STATE_DORMANT, &dev->state))
3462 		linkwatch_fire_event(dev);
3463 }
3464 
3465 /**
3466  *	netif_dormant_off - set device as not dormant.
3467  *	@dev: network device
3468  *
3469  * Device is not in dormant state.
3470  */
3471 static inline void netif_dormant_off(struct net_device *dev)
3472 {
3473 	if (test_and_clear_bit(__LINK_STATE_DORMANT, &dev->state))
3474 		linkwatch_fire_event(dev);
3475 }
3476 
3477 /**
3478  *	netif_dormant - test if device is dormant
3479  *	@dev: network device
3480  *
3481  * Check if device is dormant.
3482  */
3483 static inline bool netif_dormant(const struct net_device *dev)
3484 {
3485 	return test_bit(__LINK_STATE_DORMANT, &dev->state);
3486 }
3487 
3488 
3489 /**
3490  *	netif_oper_up - test if device is operational
3491  *	@dev: network device
3492  *
3493  * Check if carrier is operational
3494  */
3495 static inline bool netif_oper_up(const struct net_device *dev)
3496 {
3497 	return (dev->operstate == IF_OPER_UP ||
3498 		dev->operstate == IF_OPER_UNKNOWN /* backward compat */);
3499 }
3500 
3501 /**
3502  *	netif_device_present - is device available or removed
3503  *	@dev: network device
3504  *
3505  * Check if device has not been removed from system.
3506  */
3507 static inline bool netif_device_present(struct net_device *dev)
3508 {
3509 	return test_bit(__LINK_STATE_PRESENT, &dev->state);
3510 }
3511 
3512 void netif_device_detach(struct net_device *dev);
3513 
3514 void netif_device_attach(struct net_device *dev);
3515 
3516 /*
3517  * Network interface message level settings
3518  */
3519 
3520 enum {
3521 	NETIF_MSG_DRV		= 0x0001,
3522 	NETIF_MSG_PROBE		= 0x0002,
3523 	NETIF_MSG_LINK		= 0x0004,
3524 	NETIF_MSG_TIMER		= 0x0008,
3525 	NETIF_MSG_IFDOWN	= 0x0010,
3526 	NETIF_MSG_IFUP		= 0x0020,
3527 	NETIF_MSG_RX_ERR	= 0x0040,
3528 	NETIF_MSG_TX_ERR	= 0x0080,
3529 	NETIF_MSG_TX_QUEUED	= 0x0100,
3530 	NETIF_MSG_INTR		= 0x0200,
3531 	NETIF_MSG_TX_DONE	= 0x0400,
3532 	NETIF_MSG_RX_STATUS	= 0x0800,
3533 	NETIF_MSG_PKTDATA	= 0x1000,
3534 	NETIF_MSG_HW		= 0x2000,
3535 	NETIF_MSG_WOL		= 0x4000,
3536 };
3537 
3538 #define netif_msg_drv(p)	((p)->msg_enable & NETIF_MSG_DRV)
3539 #define netif_msg_probe(p)	((p)->msg_enable & NETIF_MSG_PROBE)
3540 #define netif_msg_link(p)	((p)->msg_enable & NETIF_MSG_LINK)
3541 #define netif_msg_timer(p)	((p)->msg_enable & NETIF_MSG_TIMER)
3542 #define netif_msg_ifdown(p)	((p)->msg_enable & NETIF_MSG_IFDOWN)
3543 #define netif_msg_ifup(p)	((p)->msg_enable & NETIF_MSG_IFUP)
3544 #define netif_msg_rx_err(p)	((p)->msg_enable & NETIF_MSG_RX_ERR)
3545 #define netif_msg_tx_err(p)	((p)->msg_enable & NETIF_MSG_TX_ERR)
3546 #define netif_msg_tx_queued(p)	((p)->msg_enable & NETIF_MSG_TX_QUEUED)
3547 #define netif_msg_intr(p)	((p)->msg_enable & NETIF_MSG_INTR)
3548 #define netif_msg_tx_done(p)	((p)->msg_enable & NETIF_MSG_TX_DONE)
3549 #define netif_msg_rx_status(p)	((p)->msg_enable & NETIF_MSG_RX_STATUS)
3550 #define netif_msg_pktdata(p)	((p)->msg_enable & NETIF_MSG_PKTDATA)
3551 #define netif_msg_hw(p)		((p)->msg_enable & NETIF_MSG_HW)
3552 #define netif_msg_wol(p)	((p)->msg_enable & NETIF_MSG_WOL)
3553 
3554 static inline u32 netif_msg_init(int debug_value, int default_msg_enable_bits)
3555 {
3556 	/* use default */
3557 	if (debug_value < 0 || debug_value >= (sizeof(u32) * 8))
3558 		return default_msg_enable_bits;
3559 	if (debug_value == 0)	/* no output */
3560 		return 0;
3561 	/* set low N bits */
3562 	return (1 << debug_value) - 1;
3563 }
3564 
3565 static inline void __netif_tx_lock(struct netdev_queue *txq, int cpu)
3566 {
3567 	spin_lock(&txq->_xmit_lock);
3568 	txq->xmit_lock_owner = cpu;
3569 }
3570 
3571 static inline bool __netif_tx_acquire(struct netdev_queue *txq)
3572 {
3573 	__acquire(&txq->_xmit_lock);
3574 	return true;
3575 }
3576 
3577 static inline void __netif_tx_release(struct netdev_queue *txq)
3578 {
3579 	__release(&txq->_xmit_lock);
3580 }
3581 
3582 static inline void __netif_tx_lock_bh(struct netdev_queue *txq)
3583 {
3584 	spin_lock_bh(&txq->_xmit_lock);
3585 	txq->xmit_lock_owner = smp_processor_id();
3586 }
3587 
3588 static inline bool __netif_tx_trylock(struct netdev_queue *txq)
3589 {
3590 	bool ok = spin_trylock(&txq->_xmit_lock);
3591 	if (likely(ok))
3592 		txq->xmit_lock_owner = smp_processor_id();
3593 	return ok;
3594 }
3595 
3596 static inline void __netif_tx_unlock(struct netdev_queue *txq)
3597 {
3598 	txq->xmit_lock_owner = -1;
3599 	spin_unlock(&txq->_xmit_lock);
3600 }
3601 
3602 static inline void __netif_tx_unlock_bh(struct netdev_queue *txq)
3603 {
3604 	txq->xmit_lock_owner = -1;
3605 	spin_unlock_bh(&txq->_xmit_lock);
3606 }
3607 
3608 static inline void txq_trans_update(struct netdev_queue *txq)
3609 {
3610 	if (txq->xmit_lock_owner != -1)
3611 		txq->trans_start = jiffies;
3612 }
3613 
3614 /* legacy drivers only, netdev_start_xmit() sets txq->trans_start */
3615 static inline void netif_trans_update(struct net_device *dev)
3616 {
3617 	struct netdev_queue *txq = netdev_get_tx_queue(dev, 0);
3618 
3619 	if (txq->trans_start != jiffies)
3620 		txq->trans_start = jiffies;
3621 }
3622 
3623 /**
3624  *	netif_tx_lock - grab network device transmit lock
3625  *	@dev: network device
3626  *
3627  * Get network device transmit lock
3628  */
3629 static inline void netif_tx_lock(struct net_device *dev)
3630 {
3631 	unsigned int i;
3632 	int cpu;
3633 
3634 	spin_lock(&dev->tx_global_lock);
3635 	cpu = smp_processor_id();
3636 	for (i = 0; i < dev->num_tx_queues; i++) {
3637 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
3638 
3639 		/* We are the only thread of execution doing a
3640 		 * freeze, but we have to grab the _xmit_lock in
3641 		 * order to synchronize with threads which are in
3642 		 * the ->hard_start_xmit() handler and already
3643 		 * checked the frozen bit.
3644 		 */
3645 		__netif_tx_lock(txq, cpu);
3646 		set_bit(__QUEUE_STATE_FROZEN, &txq->state);
3647 		__netif_tx_unlock(txq);
3648 	}
3649 }
3650 
3651 static inline void netif_tx_lock_bh(struct net_device *dev)
3652 {
3653 	local_bh_disable();
3654 	netif_tx_lock(dev);
3655 }
3656 
3657 static inline void netif_tx_unlock(struct net_device *dev)
3658 {
3659 	unsigned int i;
3660 
3661 	for (i = 0; i < dev->num_tx_queues; i++) {
3662 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
3663 
3664 		/* No need to grab the _xmit_lock here.  If the
3665 		 * queue is not stopped for another reason, we
3666 		 * force a schedule.
3667 		 */
3668 		clear_bit(__QUEUE_STATE_FROZEN, &txq->state);
3669 		netif_schedule_queue(txq);
3670 	}
3671 	spin_unlock(&dev->tx_global_lock);
3672 }
3673 
3674 static inline void netif_tx_unlock_bh(struct net_device *dev)
3675 {
3676 	netif_tx_unlock(dev);
3677 	local_bh_enable();
3678 }
3679 
3680 #define HARD_TX_LOCK(dev, txq, cpu) {			\
3681 	if ((dev->features & NETIF_F_LLTX) == 0) {	\
3682 		__netif_tx_lock(txq, cpu);		\
3683 	} else {					\
3684 		__netif_tx_acquire(txq);		\
3685 	}						\
3686 }
3687 
3688 #define HARD_TX_TRYLOCK(dev, txq)			\
3689 	(((dev->features & NETIF_F_LLTX) == 0) ?	\
3690 		__netif_tx_trylock(txq) :		\
3691 		__netif_tx_acquire(txq))
3692 
3693 #define HARD_TX_UNLOCK(dev, txq) {			\
3694 	if ((dev->features & NETIF_F_LLTX) == 0) {	\
3695 		__netif_tx_unlock(txq);			\
3696 	} else {					\
3697 		__netif_tx_release(txq);		\
3698 	}						\
3699 }
3700 
3701 static inline void netif_tx_disable(struct net_device *dev)
3702 {
3703 	unsigned int i;
3704 	int cpu;
3705 
3706 	local_bh_disable();
3707 	cpu = smp_processor_id();
3708 	for (i = 0; i < dev->num_tx_queues; i++) {
3709 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
3710 
3711 		__netif_tx_lock(txq, cpu);
3712 		netif_tx_stop_queue(txq);
3713 		__netif_tx_unlock(txq);
3714 	}
3715 	local_bh_enable();
3716 }
3717 
3718 static inline void netif_addr_lock(struct net_device *dev)
3719 {
3720 	spin_lock(&dev->addr_list_lock);
3721 }
3722 
3723 static inline void netif_addr_lock_nested(struct net_device *dev)
3724 {
3725 	int subclass = SINGLE_DEPTH_NESTING;
3726 
3727 	if (dev->netdev_ops->ndo_get_lock_subclass)
3728 		subclass = dev->netdev_ops->ndo_get_lock_subclass(dev);
3729 
3730 	spin_lock_nested(&dev->addr_list_lock, subclass);
3731 }
3732 
3733 static inline void netif_addr_lock_bh(struct net_device *dev)
3734 {
3735 	spin_lock_bh(&dev->addr_list_lock);
3736 }
3737 
3738 static inline void netif_addr_unlock(struct net_device *dev)
3739 {
3740 	spin_unlock(&dev->addr_list_lock);
3741 }
3742 
3743 static inline void netif_addr_unlock_bh(struct net_device *dev)
3744 {
3745 	spin_unlock_bh(&dev->addr_list_lock);
3746 }
3747 
3748 /*
3749  * dev_addrs walker. Should be used only for read access. Call with
3750  * rcu_read_lock held.
3751  */
3752 #define for_each_dev_addr(dev, ha) \
3753 		list_for_each_entry_rcu(ha, &dev->dev_addrs.list, list)
3754 
3755 /* These functions live elsewhere (drivers/net/net_init.c, but related) */
3756 
3757 void ether_setup(struct net_device *dev);
3758 
3759 /* Support for loadable net-drivers */
3760 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
3761 				    unsigned char name_assign_type,
3762 				    void (*setup)(struct net_device *),
3763 				    unsigned int txqs, unsigned int rxqs);
3764 int dev_get_valid_name(struct net *net, struct net_device *dev,
3765 		       const char *name);
3766 
3767 #define alloc_netdev(sizeof_priv, name, name_assign_type, setup) \
3768 	alloc_netdev_mqs(sizeof_priv, name, name_assign_type, setup, 1, 1)
3769 
3770 #define alloc_netdev_mq(sizeof_priv, name, name_assign_type, setup, count) \
3771 	alloc_netdev_mqs(sizeof_priv, name, name_assign_type, setup, count, \
3772 			 count)
3773 
3774 int register_netdev(struct net_device *dev);
3775 void unregister_netdev(struct net_device *dev);
3776 
3777 /* General hardware address lists handling functions */
3778 int __hw_addr_sync(struct netdev_hw_addr_list *to_list,
3779 		   struct netdev_hw_addr_list *from_list, int addr_len);
3780 void __hw_addr_unsync(struct netdev_hw_addr_list *to_list,
3781 		      struct netdev_hw_addr_list *from_list, int addr_len);
3782 int __hw_addr_sync_dev(struct netdev_hw_addr_list *list,
3783 		       struct net_device *dev,
3784 		       int (*sync)(struct net_device *, const unsigned char *),
3785 		       int (*unsync)(struct net_device *,
3786 				     const unsigned char *));
3787 void __hw_addr_unsync_dev(struct netdev_hw_addr_list *list,
3788 			  struct net_device *dev,
3789 			  int (*unsync)(struct net_device *,
3790 					const unsigned char *));
3791 void __hw_addr_init(struct netdev_hw_addr_list *list);
3792 
3793 /* Functions used for device addresses handling */
3794 int dev_addr_add(struct net_device *dev, const unsigned char *addr,
3795 		 unsigned char addr_type);
3796 int dev_addr_del(struct net_device *dev, const unsigned char *addr,
3797 		 unsigned char addr_type);
3798 void dev_addr_flush(struct net_device *dev);
3799 int dev_addr_init(struct net_device *dev);
3800 
3801 /* Functions used for unicast addresses handling */
3802 int dev_uc_add(struct net_device *dev, const unsigned char *addr);
3803 int dev_uc_add_excl(struct net_device *dev, const unsigned char *addr);
3804 int dev_uc_del(struct net_device *dev, const unsigned char *addr);
3805 int dev_uc_sync(struct net_device *to, struct net_device *from);
3806 int dev_uc_sync_multiple(struct net_device *to, struct net_device *from);
3807 void dev_uc_unsync(struct net_device *to, struct net_device *from);
3808 void dev_uc_flush(struct net_device *dev);
3809 void dev_uc_init(struct net_device *dev);
3810 
3811 /**
3812  *  __dev_uc_sync - Synchonize device's unicast list
3813  *  @dev:  device to sync
3814  *  @sync: function to call if address should be added
3815  *  @unsync: function to call if address should be removed
3816  *
3817  *  Add newly added addresses to the interface, and release
3818  *  addresses that have been deleted.
3819  */
3820 static inline int __dev_uc_sync(struct net_device *dev,
3821 				int (*sync)(struct net_device *,
3822 					    const unsigned char *),
3823 				int (*unsync)(struct net_device *,
3824 					      const unsigned char *))
3825 {
3826 	return __hw_addr_sync_dev(&dev->uc, dev, sync, unsync);
3827 }
3828 
3829 /**
3830  *  __dev_uc_unsync - Remove synchronized addresses from device
3831  *  @dev:  device to sync
3832  *  @unsync: function to call if address should be removed
3833  *
3834  *  Remove all addresses that were added to the device by dev_uc_sync().
3835  */
3836 static inline void __dev_uc_unsync(struct net_device *dev,
3837 				   int (*unsync)(struct net_device *,
3838 						 const unsigned char *))
3839 {
3840 	__hw_addr_unsync_dev(&dev->uc, dev, unsync);
3841 }
3842 
3843 /* Functions used for multicast addresses handling */
3844 int dev_mc_add(struct net_device *dev, const unsigned char *addr);
3845 int dev_mc_add_global(struct net_device *dev, const unsigned char *addr);
3846 int dev_mc_add_excl(struct net_device *dev, const unsigned char *addr);
3847 int dev_mc_del(struct net_device *dev, const unsigned char *addr);
3848 int dev_mc_del_global(struct net_device *dev, const unsigned char *addr);
3849 int dev_mc_sync(struct net_device *to, struct net_device *from);
3850 int dev_mc_sync_multiple(struct net_device *to, struct net_device *from);
3851 void dev_mc_unsync(struct net_device *to, struct net_device *from);
3852 void dev_mc_flush(struct net_device *dev);
3853 void dev_mc_init(struct net_device *dev);
3854 
3855 /**
3856  *  __dev_mc_sync - Synchonize device's multicast list
3857  *  @dev:  device to sync
3858  *  @sync: function to call if address should be added
3859  *  @unsync: function to call if address should be removed
3860  *
3861  *  Add newly added addresses to the interface, and release
3862  *  addresses that have been deleted.
3863  */
3864 static inline int __dev_mc_sync(struct net_device *dev,
3865 				int (*sync)(struct net_device *,
3866 					    const unsigned char *),
3867 				int (*unsync)(struct net_device *,
3868 					      const unsigned char *))
3869 {
3870 	return __hw_addr_sync_dev(&dev->mc, dev, sync, unsync);
3871 }
3872 
3873 /**
3874  *  __dev_mc_unsync - Remove synchronized addresses from device
3875  *  @dev:  device to sync
3876  *  @unsync: function to call if address should be removed
3877  *
3878  *  Remove all addresses that were added to the device by dev_mc_sync().
3879  */
3880 static inline void __dev_mc_unsync(struct net_device *dev,
3881 				   int (*unsync)(struct net_device *,
3882 						 const unsigned char *))
3883 {
3884 	__hw_addr_unsync_dev(&dev->mc, dev, unsync);
3885 }
3886 
3887 /* Functions used for secondary unicast and multicast support */
3888 void dev_set_rx_mode(struct net_device *dev);
3889 void __dev_set_rx_mode(struct net_device *dev);
3890 int dev_set_promiscuity(struct net_device *dev, int inc);
3891 int dev_set_allmulti(struct net_device *dev, int inc);
3892 void netdev_state_change(struct net_device *dev);
3893 void netdev_notify_peers(struct net_device *dev);
3894 void netdev_features_change(struct net_device *dev);
3895 /* Load a device via the kmod */
3896 void dev_load(struct net *net, const char *name);
3897 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
3898 					struct rtnl_link_stats64 *storage);
3899 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
3900 			     const struct net_device_stats *netdev_stats);
3901 
3902 extern int		netdev_max_backlog;
3903 extern int		netdev_tstamp_prequeue;
3904 extern int		weight_p;
3905 extern int		dev_weight_rx_bias;
3906 extern int		dev_weight_tx_bias;
3907 extern int		dev_rx_weight;
3908 extern int		dev_tx_weight;
3909 
3910 bool netdev_has_upper_dev(struct net_device *dev, struct net_device *upper_dev);
3911 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
3912 						     struct list_head **iter);
3913 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
3914 						     struct list_head **iter);
3915 
3916 /* iterate through upper list, must be called under RCU read lock */
3917 #define netdev_for_each_upper_dev_rcu(dev, updev, iter) \
3918 	for (iter = &(dev)->adj_list.upper, \
3919 	     updev = netdev_upper_get_next_dev_rcu(dev, &(iter)); \
3920 	     updev; \
3921 	     updev = netdev_upper_get_next_dev_rcu(dev, &(iter)))
3922 
3923 int netdev_walk_all_upper_dev_rcu(struct net_device *dev,
3924 				  int (*fn)(struct net_device *upper_dev,
3925 					    void *data),
3926 				  void *data);
3927 
3928 bool netdev_has_upper_dev_all_rcu(struct net_device *dev,
3929 				  struct net_device *upper_dev);
3930 
3931 bool netdev_has_any_upper_dev(struct net_device *dev);
3932 
3933 void *netdev_lower_get_next_private(struct net_device *dev,
3934 				    struct list_head **iter);
3935 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
3936 					struct list_head **iter);
3937 
3938 #define netdev_for_each_lower_private(dev, priv, iter) \
3939 	for (iter = (dev)->adj_list.lower.next, \
3940 	     priv = netdev_lower_get_next_private(dev, &(iter)); \
3941 	     priv; \
3942 	     priv = netdev_lower_get_next_private(dev, &(iter)))
3943 
3944 #define netdev_for_each_lower_private_rcu(dev, priv, iter) \
3945 	for (iter = &(dev)->adj_list.lower, \
3946 	     priv = netdev_lower_get_next_private_rcu(dev, &(iter)); \
3947 	     priv; \
3948 	     priv = netdev_lower_get_next_private_rcu(dev, &(iter)))
3949 
3950 void *netdev_lower_get_next(struct net_device *dev,
3951 				struct list_head **iter);
3952 
3953 #define netdev_for_each_lower_dev(dev, ldev, iter) \
3954 	for (iter = (dev)->adj_list.lower.next, \
3955 	     ldev = netdev_lower_get_next(dev, &(iter)); \
3956 	     ldev; \
3957 	     ldev = netdev_lower_get_next(dev, &(iter)))
3958 
3959 struct net_device *netdev_all_lower_get_next(struct net_device *dev,
3960 					     struct list_head **iter);
3961 struct net_device *netdev_all_lower_get_next_rcu(struct net_device *dev,
3962 						 struct list_head **iter);
3963 
3964 int netdev_walk_all_lower_dev(struct net_device *dev,
3965 			      int (*fn)(struct net_device *lower_dev,
3966 					void *data),
3967 			      void *data);
3968 int netdev_walk_all_lower_dev_rcu(struct net_device *dev,
3969 				  int (*fn)(struct net_device *lower_dev,
3970 					    void *data),
3971 				  void *data);
3972 
3973 void *netdev_adjacent_get_private(struct list_head *adj_list);
3974 void *netdev_lower_get_first_private_rcu(struct net_device *dev);
3975 struct net_device *netdev_master_upper_dev_get(struct net_device *dev);
3976 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev);
3977 int netdev_upper_dev_link(struct net_device *dev, struct net_device *upper_dev,
3978 			  struct netlink_ext_ack *extack);
3979 int netdev_master_upper_dev_link(struct net_device *dev,
3980 				 struct net_device *upper_dev,
3981 				 void *upper_priv, void *upper_info,
3982 				 struct netlink_ext_ack *extack);
3983 void netdev_upper_dev_unlink(struct net_device *dev,
3984 			     struct net_device *upper_dev);
3985 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname);
3986 void *netdev_lower_dev_get_private(struct net_device *dev,
3987 				   struct net_device *lower_dev);
3988 void netdev_lower_state_changed(struct net_device *lower_dev,
3989 				void *lower_state_info);
3990 
3991 /* RSS keys are 40 or 52 bytes long */
3992 #define NETDEV_RSS_KEY_LEN 52
3993 extern u8 netdev_rss_key[NETDEV_RSS_KEY_LEN] __read_mostly;
3994 void netdev_rss_key_fill(void *buffer, size_t len);
3995 
3996 int dev_get_nest_level(struct net_device *dev);
3997 int skb_checksum_help(struct sk_buff *skb);
3998 int skb_crc32c_csum_help(struct sk_buff *skb);
3999 int skb_csum_hwoffload_help(struct sk_buff *skb,
4000 			    const netdev_features_t features);
4001 
4002 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
4003 				  netdev_features_t features, bool tx_path);
4004 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
4005 				    netdev_features_t features);
4006 
4007 struct netdev_bonding_info {
4008 	ifslave	slave;
4009 	ifbond	master;
4010 };
4011 
4012 struct netdev_notifier_bonding_info {
4013 	struct netdev_notifier_info info; /* must be first */
4014 	struct netdev_bonding_info  bonding_info;
4015 };
4016 
4017 void netdev_bonding_info_change(struct net_device *dev,
4018 				struct netdev_bonding_info *bonding_info);
4019 
4020 static inline
4021 struct sk_buff *skb_gso_segment(struct sk_buff *skb, netdev_features_t features)
4022 {
4023 	return __skb_gso_segment(skb, features, true);
4024 }
4025 __be16 skb_network_protocol(struct sk_buff *skb, int *depth);
4026 
4027 static inline bool can_checksum_protocol(netdev_features_t features,
4028 					 __be16 protocol)
4029 {
4030 	if (protocol == htons(ETH_P_FCOE))
4031 		return !!(features & NETIF_F_FCOE_CRC);
4032 
4033 	/* Assume this is an IP checksum (not SCTP CRC) */
4034 
4035 	if (features & NETIF_F_HW_CSUM) {
4036 		/* Can checksum everything */
4037 		return true;
4038 	}
4039 
4040 	switch (protocol) {
4041 	case htons(ETH_P_IP):
4042 		return !!(features & NETIF_F_IP_CSUM);
4043 	case htons(ETH_P_IPV6):
4044 		return !!(features & NETIF_F_IPV6_CSUM);
4045 	default:
4046 		return false;
4047 	}
4048 }
4049 
4050 #ifdef CONFIG_BUG
4051 void netdev_rx_csum_fault(struct net_device *dev);
4052 #else
4053 static inline void netdev_rx_csum_fault(struct net_device *dev)
4054 {
4055 }
4056 #endif
4057 /* rx skb timestamps */
4058 void net_enable_timestamp(void);
4059 void net_disable_timestamp(void);
4060 
4061 #ifdef CONFIG_PROC_FS
4062 int __init dev_proc_init(void);
4063 #else
4064 #define dev_proc_init() 0
4065 #endif
4066 
4067 static inline netdev_tx_t __netdev_start_xmit(const struct net_device_ops *ops,
4068 					      struct sk_buff *skb, struct net_device *dev,
4069 					      bool more)
4070 {
4071 	skb->xmit_more = more ? 1 : 0;
4072 	return ops->ndo_start_xmit(skb, dev);
4073 }
4074 
4075 static inline netdev_tx_t netdev_start_xmit(struct sk_buff *skb, struct net_device *dev,
4076 					    struct netdev_queue *txq, bool more)
4077 {
4078 	const struct net_device_ops *ops = dev->netdev_ops;
4079 	int rc;
4080 
4081 	rc = __netdev_start_xmit(ops, skb, dev, more);
4082 	if (rc == NETDEV_TX_OK)
4083 		txq_trans_update(txq);
4084 
4085 	return rc;
4086 }
4087 
4088 int netdev_class_create_file_ns(const struct class_attribute *class_attr,
4089 				const void *ns);
4090 void netdev_class_remove_file_ns(const struct class_attribute *class_attr,
4091 				 const void *ns);
4092 
4093 static inline int netdev_class_create_file(const struct class_attribute *class_attr)
4094 {
4095 	return netdev_class_create_file_ns(class_attr, NULL);
4096 }
4097 
4098 static inline void netdev_class_remove_file(const struct class_attribute *class_attr)
4099 {
4100 	netdev_class_remove_file_ns(class_attr, NULL);
4101 }
4102 
4103 extern const struct kobj_ns_type_operations net_ns_type_operations;
4104 
4105 const char *netdev_drivername(const struct net_device *dev);
4106 
4107 void linkwatch_run_queue(void);
4108 
4109 static inline netdev_features_t netdev_intersect_features(netdev_features_t f1,
4110 							  netdev_features_t f2)
4111 {
4112 	if ((f1 ^ f2) & NETIF_F_HW_CSUM) {
4113 		if (f1 & NETIF_F_HW_CSUM)
4114 			f1 |= (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
4115 		else
4116 			f2 |= (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
4117 	}
4118 
4119 	return f1 & f2;
4120 }
4121 
4122 static inline netdev_features_t netdev_get_wanted_features(
4123 	struct net_device *dev)
4124 {
4125 	return (dev->features & ~dev->hw_features) | dev->wanted_features;
4126 }
4127 netdev_features_t netdev_increment_features(netdev_features_t all,
4128 	netdev_features_t one, netdev_features_t mask);
4129 
4130 /* Allow TSO being used on stacked device :
4131  * Performing the GSO segmentation before last device
4132  * is a performance improvement.
4133  */
4134 static inline netdev_features_t netdev_add_tso_features(netdev_features_t features,
4135 							netdev_features_t mask)
4136 {
4137 	return netdev_increment_features(features, NETIF_F_ALL_TSO, mask);
4138 }
4139 
4140 int __netdev_update_features(struct net_device *dev);
4141 void netdev_update_features(struct net_device *dev);
4142 void netdev_change_features(struct net_device *dev);
4143 
4144 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
4145 					struct net_device *dev);
4146 
4147 netdev_features_t passthru_features_check(struct sk_buff *skb,
4148 					  struct net_device *dev,
4149 					  netdev_features_t features);
4150 netdev_features_t netif_skb_features(struct sk_buff *skb);
4151 
4152 static inline bool net_gso_ok(netdev_features_t features, int gso_type)
4153 {
4154 	netdev_features_t feature = (netdev_features_t)gso_type << NETIF_F_GSO_SHIFT;
4155 
4156 	/* check flags correspondence */
4157 	BUILD_BUG_ON(SKB_GSO_TCPV4   != (NETIF_F_TSO >> NETIF_F_GSO_SHIFT));
4158 	BUILD_BUG_ON(SKB_GSO_DODGY   != (NETIF_F_GSO_ROBUST >> NETIF_F_GSO_SHIFT));
4159 	BUILD_BUG_ON(SKB_GSO_TCP_ECN != (NETIF_F_TSO_ECN >> NETIF_F_GSO_SHIFT));
4160 	BUILD_BUG_ON(SKB_GSO_TCP_FIXEDID != (NETIF_F_TSO_MANGLEID >> NETIF_F_GSO_SHIFT));
4161 	BUILD_BUG_ON(SKB_GSO_TCPV6   != (NETIF_F_TSO6 >> NETIF_F_GSO_SHIFT));
4162 	BUILD_BUG_ON(SKB_GSO_FCOE    != (NETIF_F_FSO >> NETIF_F_GSO_SHIFT));
4163 	BUILD_BUG_ON(SKB_GSO_GRE     != (NETIF_F_GSO_GRE >> NETIF_F_GSO_SHIFT));
4164 	BUILD_BUG_ON(SKB_GSO_GRE_CSUM != (NETIF_F_GSO_GRE_CSUM >> NETIF_F_GSO_SHIFT));
4165 	BUILD_BUG_ON(SKB_GSO_IPXIP4  != (NETIF_F_GSO_IPXIP4 >> NETIF_F_GSO_SHIFT));
4166 	BUILD_BUG_ON(SKB_GSO_IPXIP6  != (NETIF_F_GSO_IPXIP6 >> NETIF_F_GSO_SHIFT));
4167 	BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL != (NETIF_F_GSO_UDP_TUNNEL >> NETIF_F_GSO_SHIFT));
4168 	BUILD_BUG_ON(SKB_GSO_UDP_TUNNEL_CSUM != (NETIF_F_GSO_UDP_TUNNEL_CSUM >> NETIF_F_GSO_SHIFT));
4169 	BUILD_BUG_ON(SKB_GSO_PARTIAL != (NETIF_F_GSO_PARTIAL >> NETIF_F_GSO_SHIFT));
4170 	BUILD_BUG_ON(SKB_GSO_TUNNEL_REMCSUM != (NETIF_F_GSO_TUNNEL_REMCSUM >> NETIF_F_GSO_SHIFT));
4171 	BUILD_BUG_ON(SKB_GSO_SCTP    != (NETIF_F_GSO_SCTP >> NETIF_F_GSO_SHIFT));
4172 	BUILD_BUG_ON(SKB_GSO_ESP != (NETIF_F_GSO_ESP >> NETIF_F_GSO_SHIFT));
4173 	BUILD_BUG_ON(SKB_GSO_UDP != (NETIF_F_GSO_UDP >> NETIF_F_GSO_SHIFT));
4174 
4175 	return (features & feature) == feature;
4176 }
4177 
4178 static inline bool skb_gso_ok(struct sk_buff *skb, netdev_features_t features)
4179 {
4180 	return net_gso_ok(features, skb_shinfo(skb)->gso_type) &&
4181 	       (!skb_has_frag_list(skb) || (features & NETIF_F_FRAGLIST));
4182 }
4183 
4184 static inline bool netif_needs_gso(struct sk_buff *skb,
4185 				   netdev_features_t features)
4186 {
4187 	return skb_is_gso(skb) && (!skb_gso_ok(skb, features) ||
4188 		unlikely((skb->ip_summed != CHECKSUM_PARTIAL) &&
4189 			 (skb->ip_summed != CHECKSUM_UNNECESSARY)));
4190 }
4191 
4192 static inline void netif_set_gso_max_size(struct net_device *dev,
4193 					  unsigned int size)
4194 {
4195 	dev->gso_max_size = size;
4196 }
4197 
4198 static inline void skb_gso_error_unwind(struct sk_buff *skb, __be16 protocol,
4199 					int pulled_hlen, u16 mac_offset,
4200 					int mac_len)
4201 {
4202 	skb->protocol = protocol;
4203 	skb->encapsulation = 1;
4204 	skb_push(skb, pulled_hlen);
4205 	skb_reset_transport_header(skb);
4206 	skb->mac_header = mac_offset;
4207 	skb->network_header = skb->mac_header + mac_len;
4208 	skb->mac_len = mac_len;
4209 }
4210 
4211 static inline bool netif_is_macsec(const struct net_device *dev)
4212 {
4213 	return dev->priv_flags & IFF_MACSEC;
4214 }
4215 
4216 static inline bool netif_is_macvlan(const struct net_device *dev)
4217 {
4218 	return dev->priv_flags & IFF_MACVLAN;
4219 }
4220 
4221 static inline bool netif_is_macvlan_port(const struct net_device *dev)
4222 {
4223 	return dev->priv_flags & IFF_MACVLAN_PORT;
4224 }
4225 
4226 static inline bool netif_is_ipvlan(const struct net_device *dev)
4227 {
4228 	return dev->priv_flags & IFF_IPVLAN_SLAVE;
4229 }
4230 
4231 static inline bool netif_is_ipvlan_port(const struct net_device *dev)
4232 {
4233 	return dev->priv_flags & IFF_IPVLAN_MASTER;
4234 }
4235 
4236 static inline bool netif_is_bond_master(const struct net_device *dev)
4237 {
4238 	return dev->flags & IFF_MASTER && dev->priv_flags & IFF_BONDING;
4239 }
4240 
4241 static inline bool netif_is_bond_slave(const struct net_device *dev)
4242 {
4243 	return dev->flags & IFF_SLAVE && dev->priv_flags & IFF_BONDING;
4244 }
4245 
4246 static inline bool netif_supports_nofcs(struct net_device *dev)
4247 {
4248 	return dev->priv_flags & IFF_SUPP_NOFCS;
4249 }
4250 
4251 static inline bool netif_is_l3_master(const struct net_device *dev)
4252 {
4253 	return dev->priv_flags & IFF_L3MDEV_MASTER;
4254 }
4255 
4256 static inline bool netif_is_l3_slave(const struct net_device *dev)
4257 {
4258 	return dev->priv_flags & IFF_L3MDEV_SLAVE;
4259 }
4260 
4261 static inline bool netif_is_bridge_master(const struct net_device *dev)
4262 {
4263 	return dev->priv_flags & IFF_EBRIDGE;
4264 }
4265 
4266 static inline bool netif_is_bridge_port(const struct net_device *dev)
4267 {
4268 	return dev->priv_flags & IFF_BRIDGE_PORT;
4269 }
4270 
4271 static inline bool netif_is_ovs_master(const struct net_device *dev)
4272 {
4273 	return dev->priv_flags & IFF_OPENVSWITCH;
4274 }
4275 
4276 static inline bool netif_is_ovs_port(const struct net_device *dev)
4277 {
4278 	return dev->priv_flags & IFF_OVS_DATAPATH;
4279 }
4280 
4281 static inline bool netif_is_team_master(const struct net_device *dev)
4282 {
4283 	return dev->priv_flags & IFF_TEAM;
4284 }
4285 
4286 static inline bool netif_is_team_port(const struct net_device *dev)
4287 {
4288 	return dev->priv_flags & IFF_TEAM_PORT;
4289 }
4290 
4291 static inline bool netif_is_lag_master(const struct net_device *dev)
4292 {
4293 	return netif_is_bond_master(dev) || netif_is_team_master(dev);
4294 }
4295 
4296 static inline bool netif_is_lag_port(const struct net_device *dev)
4297 {
4298 	return netif_is_bond_slave(dev) || netif_is_team_port(dev);
4299 }
4300 
4301 static inline bool netif_is_rxfh_configured(const struct net_device *dev)
4302 {
4303 	return dev->priv_flags & IFF_RXFH_CONFIGURED;
4304 }
4305 
4306 /* This device needs to keep skb dst for qdisc enqueue or ndo_start_xmit() */
4307 static inline void netif_keep_dst(struct net_device *dev)
4308 {
4309 	dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM);
4310 }
4311 
4312 /* return true if dev can't cope with mtu frames that need vlan tag insertion */
4313 static inline bool netif_reduces_vlan_mtu(struct net_device *dev)
4314 {
4315 	/* TODO: reserve and use an additional IFF bit, if we get more users */
4316 	return dev->priv_flags & IFF_MACSEC;
4317 }
4318 
4319 extern struct pernet_operations __net_initdata loopback_net_ops;
4320 
4321 /* Logging, debugging and troubleshooting/diagnostic helpers. */
4322 
4323 /* netdev_printk helpers, similar to dev_printk */
4324 
4325 static inline const char *netdev_name(const struct net_device *dev)
4326 {
4327 	if (!dev->name[0] || strchr(dev->name, '%'))
4328 		return "(unnamed net_device)";
4329 	return dev->name;
4330 }
4331 
4332 static inline bool netdev_unregistering(const struct net_device *dev)
4333 {
4334 	return dev->reg_state == NETREG_UNREGISTERING;
4335 }
4336 
4337 static inline const char *netdev_reg_state(const struct net_device *dev)
4338 {
4339 	switch (dev->reg_state) {
4340 	case NETREG_UNINITIALIZED: return " (uninitialized)";
4341 	case NETREG_REGISTERED: return "";
4342 	case NETREG_UNREGISTERING: return " (unregistering)";
4343 	case NETREG_UNREGISTERED: return " (unregistered)";
4344 	case NETREG_RELEASED: return " (released)";
4345 	case NETREG_DUMMY: return " (dummy)";
4346 	}
4347 
4348 	WARN_ONCE(1, "%s: unknown reg_state %d\n", dev->name, dev->reg_state);
4349 	return " (unknown)";
4350 }
4351 
4352 __printf(3, 4)
4353 void netdev_printk(const char *level, const struct net_device *dev,
4354 		   const char *format, ...);
4355 __printf(2, 3)
4356 void netdev_emerg(const struct net_device *dev, const char *format, ...);
4357 __printf(2, 3)
4358 void netdev_alert(const struct net_device *dev, const char *format, ...);
4359 __printf(2, 3)
4360 void netdev_crit(const struct net_device *dev, const char *format, ...);
4361 __printf(2, 3)
4362 void netdev_err(const struct net_device *dev, const char *format, ...);
4363 __printf(2, 3)
4364 void netdev_warn(const struct net_device *dev, const char *format, ...);
4365 __printf(2, 3)
4366 void netdev_notice(const struct net_device *dev, const char *format, ...);
4367 __printf(2, 3)
4368 void netdev_info(const struct net_device *dev, const char *format, ...);
4369 
4370 #define netdev_level_once(level, dev, fmt, ...)			\
4371 do {								\
4372 	static bool __print_once __read_mostly;			\
4373 								\
4374 	if (!__print_once) {					\
4375 		__print_once = true;				\
4376 		netdev_printk(level, dev, fmt, ##__VA_ARGS__);	\
4377 	}							\
4378 } while (0)
4379 
4380 #define netdev_emerg_once(dev, fmt, ...) \
4381 	netdev_level_once(KERN_EMERG, dev, fmt, ##__VA_ARGS__)
4382 #define netdev_alert_once(dev, fmt, ...) \
4383 	netdev_level_once(KERN_ALERT, dev, fmt, ##__VA_ARGS__)
4384 #define netdev_crit_once(dev, fmt, ...) \
4385 	netdev_level_once(KERN_CRIT, dev, fmt, ##__VA_ARGS__)
4386 #define netdev_err_once(dev, fmt, ...) \
4387 	netdev_level_once(KERN_ERR, dev, fmt, ##__VA_ARGS__)
4388 #define netdev_warn_once(dev, fmt, ...) \
4389 	netdev_level_once(KERN_WARNING, dev, fmt, ##__VA_ARGS__)
4390 #define netdev_notice_once(dev, fmt, ...) \
4391 	netdev_level_once(KERN_NOTICE, dev, fmt, ##__VA_ARGS__)
4392 #define netdev_info_once(dev, fmt, ...) \
4393 	netdev_level_once(KERN_INFO, dev, fmt, ##__VA_ARGS__)
4394 
4395 #define MODULE_ALIAS_NETDEV(device) \
4396 	MODULE_ALIAS("netdev-" device)
4397 
4398 #if defined(CONFIG_DYNAMIC_DEBUG)
4399 #define netdev_dbg(__dev, format, args...)			\
4400 do {								\
4401 	dynamic_netdev_dbg(__dev, format, ##args);		\
4402 } while (0)
4403 #elif defined(DEBUG)
4404 #define netdev_dbg(__dev, format, args...)			\
4405 	netdev_printk(KERN_DEBUG, __dev, format, ##args)
4406 #else
4407 #define netdev_dbg(__dev, format, args...)			\
4408 ({								\
4409 	if (0)							\
4410 		netdev_printk(KERN_DEBUG, __dev, format, ##args); \
4411 })
4412 #endif
4413 
4414 #if defined(VERBOSE_DEBUG)
4415 #define netdev_vdbg	netdev_dbg
4416 #else
4417 
4418 #define netdev_vdbg(dev, format, args...)			\
4419 ({								\
4420 	if (0)							\
4421 		netdev_printk(KERN_DEBUG, dev, format, ##args);	\
4422 	0;							\
4423 })
4424 #endif
4425 
4426 /*
4427  * netdev_WARN() acts like dev_printk(), but with the key difference
4428  * of using a WARN/WARN_ON to get the message out, including the
4429  * file/line information and a backtrace.
4430  */
4431 #define netdev_WARN(dev, format, args...)			\
4432 	WARN(1, "netdevice: %s%s: " format, netdev_name(dev),	\
4433 	     netdev_reg_state(dev), ##args)
4434 
4435 #define netdev_WARN_ONCE(dev, format, args...)				\
4436 	WARN_ONCE(1, "netdevice: %s%s: " format, netdev_name(dev),	\
4437 		  netdev_reg_state(dev), ##args)
4438 
4439 /* netif printk helpers, similar to netdev_printk */
4440 
4441 #define netif_printk(priv, type, level, dev, fmt, args...)	\
4442 do {					  			\
4443 	if (netif_msg_##type(priv))				\
4444 		netdev_printk(level, (dev), fmt, ##args);	\
4445 } while (0)
4446 
4447 #define netif_level(level, priv, type, dev, fmt, args...)	\
4448 do {								\
4449 	if (netif_msg_##type(priv))				\
4450 		netdev_##level(dev, fmt, ##args);		\
4451 } while (0)
4452 
4453 #define netif_emerg(priv, type, dev, fmt, args...)		\
4454 	netif_level(emerg, priv, type, dev, fmt, ##args)
4455 #define netif_alert(priv, type, dev, fmt, args...)		\
4456 	netif_level(alert, priv, type, dev, fmt, ##args)
4457 #define netif_crit(priv, type, dev, fmt, args...)		\
4458 	netif_level(crit, priv, type, dev, fmt, ##args)
4459 #define netif_err(priv, type, dev, fmt, args...)		\
4460 	netif_level(err, priv, type, dev, fmt, ##args)
4461 #define netif_warn(priv, type, dev, fmt, args...)		\
4462 	netif_level(warn, priv, type, dev, fmt, ##args)
4463 #define netif_notice(priv, type, dev, fmt, args...)		\
4464 	netif_level(notice, priv, type, dev, fmt, ##args)
4465 #define netif_info(priv, type, dev, fmt, args...)		\
4466 	netif_level(info, priv, type, dev, fmt, ##args)
4467 
4468 #if defined(CONFIG_DYNAMIC_DEBUG)
4469 #define netif_dbg(priv, type, netdev, format, args...)		\
4470 do {								\
4471 	if (netif_msg_##type(priv))				\
4472 		dynamic_netdev_dbg(netdev, format, ##args);	\
4473 } while (0)
4474 #elif defined(DEBUG)
4475 #define netif_dbg(priv, type, dev, format, args...)		\
4476 	netif_printk(priv, type, KERN_DEBUG, dev, format, ##args)
4477 #else
4478 #define netif_dbg(priv, type, dev, format, args...)			\
4479 ({									\
4480 	if (0)								\
4481 		netif_printk(priv, type, KERN_DEBUG, dev, format, ##args); \
4482 	0;								\
4483 })
4484 #endif
4485 
4486 /* if @cond then downgrade to debug, else print at @level */
4487 #define netif_cond_dbg(priv, type, netdev, cond, level, fmt, args...)     \
4488 	do {                                                              \
4489 		if (cond)                                                 \
4490 			netif_dbg(priv, type, netdev, fmt, ##args);       \
4491 		else                                                      \
4492 			netif_ ## level(priv, type, netdev, fmt, ##args); \
4493 	} while (0)
4494 
4495 #if defined(VERBOSE_DEBUG)
4496 #define netif_vdbg	netif_dbg
4497 #else
4498 #define netif_vdbg(priv, type, dev, format, args...)		\
4499 ({								\
4500 	if (0)							\
4501 		netif_printk(priv, type, KERN_DEBUG, dev, format, ##args); \
4502 	0;							\
4503 })
4504 #endif
4505 
4506 /*
4507  *	The list of packet types we will receive (as opposed to discard)
4508  *	and the routines to invoke.
4509  *
4510  *	Why 16. Because with 16 the only overlap we get on a hash of the
4511  *	low nibble of the protocol value is RARP/SNAP/X.25.
4512  *
4513  *		0800	IP
4514  *		0001	802.3
4515  *		0002	AX.25
4516  *		0004	802.2
4517  *		8035	RARP
4518  *		0005	SNAP
4519  *		0805	X.25
4520  *		0806	ARP
4521  *		8137	IPX
4522  *		0009	Localtalk
4523  *		86DD	IPv6
4524  */
4525 #define PTYPE_HASH_SIZE	(16)
4526 #define PTYPE_HASH_MASK	(PTYPE_HASH_SIZE - 1)
4527 
4528 #endif	/* _LINUX_NETDEVICE_H */
4529