xref: /openbmc/linux/net/core/net-sysfs.c (revision 6d8e62c3)
1 /*
2  * net-sysfs.c - network device class and attributes
3  *
4  * Copyright (c) 2003 Stephen Hemminger <shemminger@osdl.org>
5  *
6  *	This program is free software; you can redistribute it and/or
7  *	modify it under the terms of the GNU General Public License
8  *	as published by the Free Software Foundation; either version
9  *	2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/capability.h>
13 #include <linux/kernel.h>
14 #include <linux/netdevice.h>
15 #include <net/switchdev.h>
16 #include <linux/if_arp.h>
17 #include <linux/slab.h>
18 #include <linux/nsproxy.h>
19 #include <net/sock.h>
20 #include <net/net_namespace.h>
21 #include <linux/rtnetlink.h>
22 #include <linux/vmalloc.h>
23 #include <linux/export.h>
24 #include <linux/jiffies.h>
25 #include <linux/pm_runtime.h>
26 
27 #include "net-sysfs.h"
28 
29 #ifdef CONFIG_SYSFS
30 static const char fmt_hex[] = "%#x\n";
31 static const char fmt_long_hex[] = "%#lx\n";
32 static const char fmt_dec[] = "%d\n";
33 static const char fmt_udec[] = "%u\n";
34 static const char fmt_ulong[] = "%lu\n";
35 static const char fmt_u64[] = "%llu\n";
36 
37 static inline int dev_isalive(const struct net_device *dev)
38 {
39 	return dev->reg_state <= NETREG_REGISTERED;
40 }
41 
42 /* use same locking rules as GIF* ioctl's */
43 static ssize_t netdev_show(const struct device *dev,
44 			   struct device_attribute *attr, char *buf,
45 			   ssize_t (*format)(const struct net_device *, char *))
46 {
47 	struct net_device *ndev = to_net_dev(dev);
48 	ssize_t ret = -EINVAL;
49 
50 	read_lock(&dev_base_lock);
51 	if (dev_isalive(ndev))
52 		ret = (*format)(ndev, buf);
53 	read_unlock(&dev_base_lock);
54 
55 	return ret;
56 }
57 
58 /* generate a show function for simple field */
59 #define NETDEVICE_SHOW(field, format_string)				\
60 static ssize_t format_##field(const struct net_device *dev, char *buf)	\
61 {									\
62 	return sprintf(buf, format_string, dev->field);			\
63 }									\
64 static ssize_t field##_show(struct device *dev,				\
65 			    struct device_attribute *attr, char *buf)	\
66 {									\
67 	return netdev_show(dev, attr, buf, format_##field);		\
68 }									\
69 
70 #define NETDEVICE_SHOW_RO(field, format_string)				\
71 NETDEVICE_SHOW(field, format_string);					\
72 static DEVICE_ATTR_RO(field)
73 
74 #define NETDEVICE_SHOW_RW(field, format_string)				\
75 NETDEVICE_SHOW(field, format_string);					\
76 static DEVICE_ATTR_RW(field)
77 
78 /* use same locking and permission rules as SIF* ioctl's */
79 static ssize_t netdev_store(struct device *dev, struct device_attribute *attr,
80 			    const char *buf, size_t len,
81 			    int (*set)(struct net_device *, unsigned long))
82 {
83 	struct net_device *netdev = to_net_dev(dev);
84 	struct net *net = dev_net(netdev);
85 	unsigned long new;
86 	int ret = -EINVAL;
87 
88 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
89 		return -EPERM;
90 
91 	ret = kstrtoul(buf, 0, &new);
92 	if (ret)
93 		goto err;
94 
95 	if (!rtnl_trylock())
96 		return restart_syscall();
97 
98 	if (dev_isalive(netdev)) {
99 		if ((ret = (*set)(netdev, new)) == 0)
100 			ret = len;
101 	}
102 	rtnl_unlock();
103  err:
104 	return ret;
105 }
106 
107 NETDEVICE_SHOW_RO(dev_id, fmt_hex);
108 NETDEVICE_SHOW_RO(dev_port, fmt_dec);
109 NETDEVICE_SHOW_RO(addr_assign_type, fmt_dec);
110 NETDEVICE_SHOW_RO(addr_len, fmt_dec);
111 NETDEVICE_SHOW_RO(iflink, fmt_dec);
112 NETDEVICE_SHOW_RO(ifindex, fmt_dec);
113 NETDEVICE_SHOW_RO(type, fmt_dec);
114 NETDEVICE_SHOW_RO(link_mode, fmt_dec);
115 
116 static ssize_t format_name_assign_type(const struct net_device *dev, char *buf)
117 {
118 	return sprintf(buf, fmt_dec, dev->name_assign_type);
119 }
120 
121 static ssize_t name_assign_type_show(struct device *dev,
122 				     struct device_attribute *attr,
123 				     char *buf)
124 {
125 	struct net_device *ndev = to_net_dev(dev);
126 	ssize_t ret = -EINVAL;
127 
128 	if (ndev->name_assign_type != NET_NAME_UNKNOWN)
129 		ret = netdev_show(dev, attr, buf, format_name_assign_type);
130 
131 	return ret;
132 }
133 static DEVICE_ATTR_RO(name_assign_type);
134 
135 /* use same locking rules as GIFHWADDR ioctl's */
136 static ssize_t address_show(struct device *dev, struct device_attribute *attr,
137 			    char *buf)
138 {
139 	struct net_device *ndev = to_net_dev(dev);
140 	ssize_t ret = -EINVAL;
141 
142 	read_lock(&dev_base_lock);
143 	if (dev_isalive(ndev))
144 		ret = sysfs_format_mac(buf, ndev->dev_addr, ndev->addr_len);
145 	read_unlock(&dev_base_lock);
146 	return ret;
147 }
148 static DEVICE_ATTR_RO(address);
149 
150 static ssize_t broadcast_show(struct device *dev,
151 			      struct device_attribute *attr, char *buf)
152 {
153 	struct net_device *ndev = to_net_dev(dev);
154 	if (dev_isalive(ndev))
155 		return sysfs_format_mac(buf, ndev->broadcast, ndev->addr_len);
156 	return -EINVAL;
157 }
158 static DEVICE_ATTR_RO(broadcast);
159 
160 static int change_carrier(struct net_device *dev, unsigned long new_carrier)
161 {
162 	if (!netif_running(dev))
163 		return -EINVAL;
164 	return dev_change_carrier(dev, (bool) new_carrier);
165 }
166 
167 static ssize_t carrier_store(struct device *dev, struct device_attribute *attr,
168 			     const char *buf, size_t len)
169 {
170 	return netdev_store(dev, attr, buf, len, change_carrier);
171 }
172 
173 static ssize_t carrier_show(struct device *dev,
174 			    struct device_attribute *attr, char *buf)
175 {
176 	struct net_device *netdev = to_net_dev(dev);
177 	if (netif_running(netdev)) {
178 		return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
179 	}
180 	return -EINVAL;
181 }
182 static DEVICE_ATTR_RW(carrier);
183 
184 static ssize_t speed_show(struct device *dev,
185 			  struct device_attribute *attr, char *buf)
186 {
187 	struct net_device *netdev = to_net_dev(dev);
188 	int ret = -EINVAL;
189 
190 	if (!rtnl_trylock())
191 		return restart_syscall();
192 
193 	if (netif_running(netdev)) {
194 		struct ethtool_cmd cmd;
195 		if (!__ethtool_get_settings(netdev, &cmd))
196 			ret = sprintf(buf, fmt_udec, ethtool_cmd_speed(&cmd));
197 	}
198 	rtnl_unlock();
199 	return ret;
200 }
201 static DEVICE_ATTR_RO(speed);
202 
203 static ssize_t duplex_show(struct device *dev,
204 			   struct device_attribute *attr, char *buf)
205 {
206 	struct net_device *netdev = to_net_dev(dev);
207 	int ret = -EINVAL;
208 
209 	if (!rtnl_trylock())
210 		return restart_syscall();
211 
212 	if (netif_running(netdev)) {
213 		struct ethtool_cmd cmd;
214 		if (!__ethtool_get_settings(netdev, &cmd)) {
215 			const char *duplex;
216 			switch (cmd.duplex) {
217 			case DUPLEX_HALF:
218 				duplex = "half";
219 				break;
220 			case DUPLEX_FULL:
221 				duplex = "full";
222 				break;
223 			default:
224 				duplex = "unknown";
225 				break;
226 			}
227 			ret = sprintf(buf, "%s\n", duplex);
228 		}
229 	}
230 	rtnl_unlock();
231 	return ret;
232 }
233 static DEVICE_ATTR_RO(duplex);
234 
235 static ssize_t dormant_show(struct device *dev,
236 			    struct device_attribute *attr, char *buf)
237 {
238 	struct net_device *netdev = to_net_dev(dev);
239 
240 	if (netif_running(netdev))
241 		return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
242 
243 	return -EINVAL;
244 }
245 static DEVICE_ATTR_RO(dormant);
246 
247 static const char *const operstates[] = {
248 	"unknown",
249 	"notpresent", /* currently unused */
250 	"down",
251 	"lowerlayerdown",
252 	"testing", /* currently unused */
253 	"dormant",
254 	"up"
255 };
256 
257 static ssize_t operstate_show(struct device *dev,
258 			      struct device_attribute *attr, char *buf)
259 {
260 	const struct net_device *netdev = to_net_dev(dev);
261 	unsigned char operstate;
262 
263 	read_lock(&dev_base_lock);
264 	operstate = netdev->operstate;
265 	if (!netif_running(netdev))
266 		operstate = IF_OPER_DOWN;
267 	read_unlock(&dev_base_lock);
268 
269 	if (operstate >= ARRAY_SIZE(operstates))
270 		return -EINVAL; /* should not happen */
271 
272 	return sprintf(buf, "%s\n", operstates[operstate]);
273 }
274 static DEVICE_ATTR_RO(operstate);
275 
276 static ssize_t carrier_changes_show(struct device *dev,
277 				    struct device_attribute *attr,
278 				    char *buf)
279 {
280 	struct net_device *netdev = to_net_dev(dev);
281 	return sprintf(buf, fmt_dec,
282 		       atomic_read(&netdev->carrier_changes));
283 }
284 static DEVICE_ATTR_RO(carrier_changes);
285 
286 /* read-write attributes */
287 
288 static int change_mtu(struct net_device *dev, unsigned long new_mtu)
289 {
290 	return dev_set_mtu(dev, (int) new_mtu);
291 }
292 
293 static ssize_t mtu_store(struct device *dev, struct device_attribute *attr,
294 			 const char *buf, size_t len)
295 {
296 	return netdev_store(dev, attr, buf, len, change_mtu);
297 }
298 NETDEVICE_SHOW_RW(mtu, fmt_dec);
299 
300 static int change_flags(struct net_device *dev, unsigned long new_flags)
301 {
302 	return dev_change_flags(dev, (unsigned int) new_flags);
303 }
304 
305 static ssize_t flags_store(struct device *dev, struct device_attribute *attr,
306 			   const char *buf, size_t len)
307 {
308 	return netdev_store(dev, attr, buf, len, change_flags);
309 }
310 NETDEVICE_SHOW_RW(flags, fmt_hex);
311 
312 static int change_tx_queue_len(struct net_device *dev, unsigned long new_len)
313 {
314 	dev->tx_queue_len = new_len;
315 	return 0;
316 }
317 
318 static ssize_t tx_queue_len_store(struct device *dev,
319 				  struct device_attribute *attr,
320 				  const char *buf, size_t len)
321 {
322 	if (!capable(CAP_NET_ADMIN))
323 		return -EPERM;
324 
325 	return netdev_store(dev, attr, buf, len, change_tx_queue_len);
326 }
327 NETDEVICE_SHOW_RW(tx_queue_len, fmt_ulong);
328 
329 static int change_gro_flush_timeout(struct net_device *dev, unsigned long val)
330 {
331 	dev->gro_flush_timeout = val;
332 	return 0;
333 }
334 
335 static ssize_t gro_flush_timeout_store(struct device *dev,
336 				  struct device_attribute *attr,
337 				  const char *buf, size_t len)
338 {
339 	if (!capable(CAP_NET_ADMIN))
340 		return -EPERM;
341 
342 	return netdev_store(dev, attr, buf, len, change_gro_flush_timeout);
343 }
344 NETDEVICE_SHOW_RW(gro_flush_timeout, fmt_ulong);
345 
346 static ssize_t ifalias_store(struct device *dev, struct device_attribute *attr,
347 			     const char *buf, size_t len)
348 {
349 	struct net_device *netdev = to_net_dev(dev);
350 	struct net *net = dev_net(netdev);
351 	size_t count = len;
352 	ssize_t ret;
353 
354 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
355 		return -EPERM;
356 
357 	/* ignore trailing newline */
358 	if (len >  0 && buf[len - 1] == '\n')
359 		--count;
360 
361 	if (!rtnl_trylock())
362 		return restart_syscall();
363 	ret = dev_set_alias(netdev, buf, count);
364 	rtnl_unlock();
365 
366 	return ret < 0 ? ret : len;
367 }
368 
369 static ssize_t ifalias_show(struct device *dev,
370 			    struct device_attribute *attr, char *buf)
371 {
372 	const struct net_device *netdev = to_net_dev(dev);
373 	ssize_t ret = 0;
374 
375 	if (!rtnl_trylock())
376 		return restart_syscall();
377 	if (netdev->ifalias)
378 		ret = sprintf(buf, "%s\n", netdev->ifalias);
379 	rtnl_unlock();
380 	return ret;
381 }
382 static DEVICE_ATTR_RW(ifalias);
383 
384 static int change_group(struct net_device *dev, unsigned long new_group)
385 {
386 	dev_set_group(dev, (int) new_group);
387 	return 0;
388 }
389 
390 static ssize_t group_store(struct device *dev, struct device_attribute *attr,
391 			   const char *buf, size_t len)
392 {
393 	return netdev_store(dev, attr, buf, len, change_group);
394 }
395 NETDEVICE_SHOW(group, fmt_dec);
396 static DEVICE_ATTR(netdev_group, S_IRUGO | S_IWUSR, group_show, group_store);
397 
398 static ssize_t phys_port_id_show(struct device *dev,
399 				 struct device_attribute *attr, char *buf)
400 {
401 	struct net_device *netdev = to_net_dev(dev);
402 	ssize_t ret = -EINVAL;
403 
404 	if (!rtnl_trylock())
405 		return restart_syscall();
406 
407 	if (dev_isalive(netdev)) {
408 		struct netdev_phys_item_id ppid;
409 
410 		ret = dev_get_phys_port_id(netdev, &ppid);
411 		if (!ret)
412 			ret = sprintf(buf, "%*phN\n", ppid.id_len, ppid.id);
413 	}
414 	rtnl_unlock();
415 
416 	return ret;
417 }
418 static DEVICE_ATTR_RO(phys_port_id);
419 
420 static ssize_t phys_switch_id_show(struct device *dev,
421 				   struct device_attribute *attr, char *buf)
422 {
423 	struct net_device *netdev = to_net_dev(dev);
424 	ssize_t ret = -EINVAL;
425 
426 	if (!rtnl_trylock())
427 		return restart_syscall();
428 
429 	if (dev_isalive(netdev)) {
430 		struct netdev_phys_item_id ppid;
431 
432 		ret = netdev_switch_parent_id_get(netdev, &ppid);
433 		if (!ret)
434 			ret = sprintf(buf, "%*phN\n", ppid.id_len, ppid.id);
435 	}
436 	rtnl_unlock();
437 
438 	return ret;
439 }
440 static DEVICE_ATTR_RO(phys_switch_id);
441 
442 static struct attribute *net_class_attrs[] = {
443 	&dev_attr_netdev_group.attr,
444 	&dev_attr_type.attr,
445 	&dev_attr_dev_id.attr,
446 	&dev_attr_dev_port.attr,
447 	&dev_attr_iflink.attr,
448 	&dev_attr_ifindex.attr,
449 	&dev_attr_name_assign_type.attr,
450 	&dev_attr_addr_assign_type.attr,
451 	&dev_attr_addr_len.attr,
452 	&dev_attr_link_mode.attr,
453 	&dev_attr_address.attr,
454 	&dev_attr_broadcast.attr,
455 	&dev_attr_speed.attr,
456 	&dev_attr_duplex.attr,
457 	&dev_attr_dormant.attr,
458 	&dev_attr_operstate.attr,
459 	&dev_attr_carrier_changes.attr,
460 	&dev_attr_ifalias.attr,
461 	&dev_attr_carrier.attr,
462 	&dev_attr_mtu.attr,
463 	&dev_attr_flags.attr,
464 	&dev_attr_tx_queue_len.attr,
465 	&dev_attr_gro_flush_timeout.attr,
466 	&dev_attr_phys_port_id.attr,
467 	&dev_attr_phys_switch_id.attr,
468 	NULL,
469 };
470 ATTRIBUTE_GROUPS(net_class);
471 
472 /* Show a given an attribute in the statistics group */
473 static ssize_t netstat_show(const struct device *d,
474 			    struct device_attribute *attr, char *buf,
475 			    unsigned long offset)
476 {
477 	struct net_device *dev = to_net_dev(d);
478 	ssize_t ret = -EINVAL;
479 
480 	WARN_ON(offset > sizeof(struct rtnl_link_stats64) ||
481 			offset % sizeof(u64) != 0);
482 
483 	read_lock(&dev_base_lock);
484 	if (dev_isalive(dev)) {
485 		struct rtnl_link_stats64 temp;
486 		const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
487 
488 		ret = sprintf(buf, fmt_u64, *(u64 *)(((u8 *) stats) + offset));
489 	}
490 	read_unlock(&dev_base_lock);
491 	return ret;
492 }
493 
494 /* generate a read-only statistics attribute */
495 #define NETSTAT_ENTRY(name)						\
496 static ssize_t name##_show(struct device *d,				\
497 			   struct device_attribute *attr, char *buf) 	\
498 {									\
499 	return netstat_show(d, attr, buf,				\
500 			    offsetof(struct rtnl_link_stats64, name));	\
501 }									\
502 static DEVICE_ATTR_RO(name)
503 
504 NETSTAT_ENTRY(rx_packets);
505 NETSTAT_ENTRY(tx_packets);
506 NETSTAT_ENTRY(rx_bytes);
507 NETSTAT_ENTRY(tx_bytes);
508 NETSTAT_ENTRY(rx_errors);
509 NETSTAT_ENTRY(tx_errors);
510 NETSTAT_ENTRY(rx_dropped);
511 NETSTAT_ENTRY(tx_dropped);
512 NETSTAT_ENTRY(multicast);
513 NETSTAT_ENTRY(collisions);
514 NETSTAT_ENTRY(rx_length_errors);
515 NETSTAT_ENTRY(rx_over_errors);
516 NETSTAT_ENTRY(rx_crc_errors);
517 NETSTAT_ENTRY(rx_frame_errors);
518 NETSTAT_ENTRY(rx_fifo_errors);
519 NETSTAT_ENTRY(rx_missed_errors);
520 NETSTAT_ENTRY(tx_aborted_errors);
521 NETSTAT_ENTRY(tx_carrier_errors);
522 NETSTAT_ENTRY(tx_fifo_errors);
523 NETSTAT_ENTRY(tx_heartbeat_errors);
524 NETSTAT_ENTRY(tx_window_errors);
525 NETSTAT_ENTRY(rx_compressed);
526 NETSTAT_ENTRY(tx_compressed);
527 
528 static struct attribute *netstat_attrs[] = {
529 	&dev_attr_rx_packets.attr,
530 	&dev_attr_tx_packets.attr,
531 	&dev_attr_rx_bytes.attr,
532 	&dev_attr_tx_bytes.attr,
533 	&dev_attr_rx_errors.attr,
534 	&dev_attr_tx_errors.attr,
535 	&dev_attr_rx_dropped.attr,
536 	&dev_attr_tx_dropped.attr,
537 	&dev_attr_multicast.attr,
538 	&dev_attr_collisions.attr,
539 	&dev_attr_rx_length_errors.attr,
540 	&dev_attr_rx_over_errors.attr,
541 	&dev_attr_rx_crc_errors.attr,
542 	&dev_attr_rx_frame_errors.attr,
543 	&dev_attr_rx_fifo_errors.attr,
544 	&dev_attr_rx_missed_errors.attr,
545 	&dev_attr_tx_aborted_errors.attr,
546 	&dev_attr_tx_carrier_errors.attr,
547 	&dev_attr_tx_fifo_errors.attr,
548 	&dev_attr_tx_heartbeat_errors.attr,
549 	&dev_attr_tx_window_errors.attr,
550 	&dev_attr_rx_compressed.attr,
551 	&dev_attr_tx_compressed.attr,
552 	NULL
553 };
554 
555 
556 static struct attribute_group netstat_group = {
557 	.name  = "statistics",
558 	.attrs  = netstat_attrs,
559 };
560 
561 #if IS_ENABLED(CONFIG_WIRELESS_EXT) || IS_ENABLED(CONFIG_CFG80211)
562 static struct attribute *wireless_attrs[] = {
563 	NULL
564 };
565 
566 static struct attribute_group wireless_group = {
567 	.name = "wireless",
568 	.attrs = wireless_attrs,
569 };
570 #endif
571 
572 #else /* CONFIG_SYSFS */
573 #define net_class_groups	NULL
574 #endif /* CONFIG_SYSFS */
575 
576 #ifdef CONFIG_SYSFS
577 #define to_rx_queue_attr(_attr) container_of(_attr,		\
578     struct rx_queue_attribute, attr)
579 
580 #define to_rx_queue(obj) container_of(obj, struct netdev_rx_queue, kobj)
581 
582 static ssize_t rx_queue_attr_show(struct kobject *kobj, struct attribute *attr,
583 				  char *buf)
584 {
585 	struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
586 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
587 
588 	if (!attribute->show)
589 		return -EIO;
590 
591 	return attribute->show(queue, attribute, buf);
592 }
593 
594 static ssize_t rx_queue_attr_store(struct kobject *kobj, struct attribute *attr,
595 				   const char *buf, size_t count)
596 {
597 	struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
598 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
599 
600 	if (!attribute->store)
601 		return -EIO;
602 
603 	return attribute->store(queue, attribute, buf, count);
604 }
605 
606 static const struct sysfs_ops rx_queue_sysfs_ops = {
607 	.show = rx_queue_attr_show,
608 	.store = rx_queue_attr_store,
609 };
610 
611 #ifdef CONFIG_RPS
612 static ssize_t show_rps_map(struct netdev_rx_queue *queue,
613 			    struct rx_queue_attribute *attribute, char *buf)
614 {
615 	struct rps_map *map;
616 	cpumask_var_t mask;
617 	size_t len = 0;
618 	int i;
619 
620 	if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
621 		return -ENOMEM;
622 
623 	rcu_read_lock();
624 	map = rcu_dereference(queue->rps_map);
625 	if (map)
626 		for (i = 0; i < map->len; i++)
627 			cpumask_set_cpu(map->cpus[i], mask);
628 
629 	len += cpumask_scnprintf(buf + len, PAGE_SIZE, mask);
630 	if (PAGE_SIZE - len < 3) {
631 		rcu_read_unlock();
632 		free_cpumask_var(mask);
633 		return -EINVAL;
634 	}
635 	rcu_read_unlock();
636 
637 	free_cpumask_var(mask);
638 	len += sprintf(buf + len, "\n");
639 	return len;
640 }
641 
642 static ssize_t store_rps_map(struct netdev_rx_queue *queue,
643 		      struct rx_queue_attribute *attribute,
644 		      const char *buf, size_t len)
645 {
646 	struct rps_map *old_map, *map;
647 	cpumask_var_t mask;
648 	int err, cpu, i;
649 	static DEFINE_SPINLOCK(rps_map_lock);
650 
651 	if (!capable(CAP_NET_ADMIN))
652 		return -EPERM;
653 
654 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
655 		return -ENOMEM;
656 
657 	err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
658 	if (err) {
659 		free_cpumask_var(mask);
660 		return err;
661 	}
662 
663 	map = kzalloc(max_t(unsigned int,
664 	    RPS_MAP_SIZE(cpumask_weight(mask)), L1_CACHE_BYTES),
665 	    GFP_KERNEL);
666 	if (!map) {
667 		free_cpumask_var(mask);
668 		return -ENOMEM;
669 	}
670 
671 	i = 0;
672 	for_each_cpu_and(cpu, mask, cpu_online_mask)
673 		map->cpus[i++] = cpu;
674 
675 	if (i)
676 		map->len = i;
677 	else {
678 		kfree(map);
679 		map = NULL;
680 	}
681 
682 	spin_lock(&rps_map_lock);
683 	old_map = rcu_dereference_protected(queue->rps_map,
684 					    lockdep_is_held(&rps_map_lock));
685 	rcu_assign_pointer(queue->rps_map, map);
686 	spin_unlock(&rps_map_lock);
687 
688 	if (map)
689 		static_key_slow_inc(&rps_needed);
690 	if (old_map) {
691 		kfree_rcu(old_map, rcu);
692 		static_key_slow_dec(&rps_needed);
693 	}
694 	free_cpumask_var(mask);
695 	return len;
696 }
697 
698 static ssize_t show_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
699 					   struct rx_queue_attribute *attr,
700 					   char *buf)
701 {
702 	struct rps_dev_flow_table *flow_table;
703 	unsigned long val = 0;
704 
705 	rcu_read_lock();
706 	flow_table = rcu_dereference(queue->rps_flow_table);
707 	if (flow_table)
708 		val = (unsigned long)flow_table->mask + 1;
709 	rcu_read_unlock();
710 
711 	return sprintf(buf, "%lu\n", val);
712 }
713 
714 static void rps_dev_flow_table_release(struct rcu_head *rcu)
715 {
716 	struct rps_dev_flow_table *table = container_of(rcu,
717 	    struct rps_dev_flow_table, rcu);
718 	vfree(table);
719 }
720 
721 static ssize_t store_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
722 				     struct rx_queue_attribute *attr,
723 				     const char *buf, size_t len)
724 {
725 	unsigned long mask, count;
726 	struct rps_dev_flow_table *table, *old_table;
727 	static DEFINE_SPINLOCK(rps_dev_flow_lock);
728 	int rc;
729 
730 	if (!capable(CAP_NET_ADMIN))
731 		return -EPERM;
732 
733 	rc = kstrtoul(buf, 0, &count);
734 	if (rc < 0)
735 		return rc;
736 
737 	if (count) {
738 		mask = count - 1;
739 		/* mask = roundup_pow_of_two(count) - 1;
740 		 * without overflows...
741 		 */
742 		while ((mask | (mask >> 1)) != mask)
743 			mask |= (mask >> 1);
744 		/* On 64 bit arches, must check mask fits in table->mask (u32),
745 		 * and on 32bit arches, must check
746 		 * RPS_DEV_FLOW_TABLE_SIZE(mask + 1) doesn't overflow.
747 		 */
748 #if BITS_PER_LONG > 32
749 		if (mask > (unsigned long)(u32)mask)
750 			return -EINVAL;
751 #else
752 		if (mask > (ULONG_MAX - RPS_DEV_FLOW_TABLE_SIZE(1))
753 				/ sizeof(struct rps_dev_flow)) {
754 			/* Enforce a limit to prevent overflow */
755 			return -EINVAL;
756 		}
757 #endif
758 		table = vmalloc(RPS_DEV_FLOW_TABLE_SIZE(mask + 1));
759 		if (!table)
760 			return -ENOMEM;
761 
762 		table->mask = mask;
763 		for (count = 0; count <= mask; count++)
764 			table->flows[count].cpu = RPS_NO_CPU;
765 	} else
766 		table = NULL;
767 
768 	spin_lock(&rps_dev_flow_lock);
769 	old_table = rcu_dereference_protected(queue->rps_flow_table,
770 					      lockdep_is_held(&rps_dev_flow_lock));
771 	rcu_assign_pointer(queue->rps_flow_table, table);
772 	spin_unlock(&rps_dev_flow_lock);
773 
774 	if (old_table)
775 		call_rcu(&old_table->rcu, rps_dev_flow_table_release);
776 
777 	return len;
778 }
779 
780 static struct rx_queue_attribute rps_cpus_attribute =
781 	__ATTR(rps_cpus, S_IRUGO | S_IWUSR, show_rps_map, store_rps_map);
782 
783 
784 static struct rx_queue_attribute rps_dev_flow_table_cnt_attribute =
785 	__ATTR(rps_flow_cnt, S_IRUGO | S_IWUSR,
786 	    show_rps_dev_flow_table_cnt, store_rps_dev_flow_table_cnt);
787 #endif /* CONFIG_RPS */
788 
789 static struct attribute *rx_queue_default_attrs[] = {
790 #ifdef CONFIG_RPS
791 	&rps_cpus_attribute.attr,
792 	&rps_dev_flow_table_cnt_attribute.attr,
793 #endif
794 	NULL
795 };
796 
797 static void rx_queue_release(struct kobject *kobj)
798 {
799 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
800 #ifdef CONFIG_RPS
801 	struct rps_map *map;
802 	struct rps_dev_flow_table *flow_table;
803 
804 
805 	map = rcu_dereference_protected(queue->rps_map, 1);
806 	if (map) {
807 		RCU_INIT_POINTER(queue->rps_map, NULL);
808 		kfree_rcu(map, rcu);
809 	}
810 
811 	flow_table = rcu_dereference_protected(queue->rps_flow_table, 1);
812 	if (flow_table) {
813 		RCU_INIT_POINTER(queue->rps_flow_table, NULL);
814 		call_rcu(&flow_table->rcu, rps_dev_flow_table_release);
815 	}
816 #endif
817 
818 	memset(kobj, 0, sizeof(*kobj));
819 	dev_put(queue->dev);
820 }
821 
822 static const void *rx_queue_namespace(struct kobject *kobj)
823 {
824 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
825 	struct device *dev = &queue->dev->dev;
826 	const void *ns = NULL;
827 
828 	if (dev->class && dev->class->ns_type)
829 		ns = dev->class->namespace(dev);
830 
831 	return ns;
832 }
833 
834 static struct kobj_type rx_queue_ktype = {
835 	.sysfs_ops = &rx_queue_sysfs_ops,
836 	.release = rx_queue_release,
837 	.default_attrs = rx_queue_default_attrs,
838 	.namespace = rx_queue_namespace
839 };
840 
841 static int rx_queue_add_kobject(struct net_device *dev, int index)
842 {
843 	struct netdev_rx_queue *queue = dev->_rx + index;
844 	struct kobject *kobj = &queue->kobj;
845 	int error = 0;
846 
847 	kobj->kset = dev->queues_kset;
848 	error = kobject_init_and_add(kobj, &rx_queue_ktype, NULL,
849 	    "rx-%u", index);
850 	if (error)
851 		goto exit;
852 
853 	if (dev->sysfs_rx_queue_group) {
854 		error = sysfs_create_group(kobj, dev->sysfs_rx_queue_group);
855 		if (error)
856 			goto exit;
857 	}
858 
859 	kobject_uevent(kobj, KOBJ_ADD);
860 	dev_hold(queue->dev);
861 
862 	return error;
863 exit:
864 	kobject_put(kobj);
865 	return error;
866 }
867 #endif /* CONFIG_SYSFS */
868 
869 int
870 net_rx_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
871 {
872 #ifdef CONFIG_SYSFS
873 	int i;
874 	int error = 0;
875 
876 #ifndef CONFIG_RPS
877 	if (!dev->sysfs_rx_queue_group)
878 		return 0;
879 #endif
880 	for (i = old_num; i < new_num; i++) {
881 		error = rx_queue_add_kobject(dev, i);
882 		if (error) {
883 			new_num = old_num;
884 			break;
885 		}
886 	}
887 
888 	while (--i >= new_num) {
889 		if (dev->sysfs_rx_queue_group)
890 			sysfs_remove_group(&dev->_rx[i].kobj,
891 					   dev->sysfs_rx_queue_group);
892 		kobject_put(&dev->_rx[i].kobj);
893 	}
894 
895 	return error;
896 #else
897 	return 0;
898 #endif
899 }
900 
901 #ifdef CONFIG_SYSFS
902 /*
903  * netdev_queue sysfs structures and functions.
904  */
905 struct netdev_queue_attribute {
906 	struct attribute attr;
907 	ssize_t (*show)(struct netdev_queue *queue,
908 	    struct netdev_queue_attribute *attr, char *buf);
909 	ssize_t (*store)(struct netdev_queue *queue,
910 	    struct netdev_queue_attribute *attr, const char *buf, size_t len);
911 };
912 #define to_netdev_queue_attr(_attr) container_of(_attr,		\
913     struct netdev_queue_attribute, attr)
914 
915 #define to_netdev_queue(obj) container_of(obj, struct netdev_queue, kobj)
916 
917 static ssize_t netdev_queue_attr_show(struct kobject *kobj,
918 				      struct attribute *attr, char *buf)
919 {
920 	struct netdev_queue_attribute *attribute = to_netdev_queue_attr(attr);
921 	struct netdev_queue *queue = to_netdev_queue(kobj);
922 
923 	if (!attribute->show)
924 		return -EIO;
925 
926 	return attribute->show(queue, attribute, buf);
927 }
928 
929 static ssize_t netdev_queue_attr_store(struct kobject *kobj,
930 				       struct attribute *attr,
931 				       const char *buf, size_t count)
932 {
933 	struct netdev_queue_attribute *attribute = to_netdev_queue_attr(attr);
934 	struct netdev_queue *queue = to_netdev_queue(kobj);
935 
936 	if (!attribute->store)
937 		return -EIO;
938 
939 	return attribute->store(queue, attribute, buf, count);
940 }
941 
942 static const struct sysfs_ops netdev_queue_sysfs_ops = {
943 	.show = netdev_queue_attr_show,
944 	.store = netdev_queue_attr_store,
945 };
946 
947 static ssize_t show_trans_timeout(struct netdev_queue *queue,
948 				  struct netdev_queue_attribute *attribute,
949 				  char *buf)
950 {
951 	unsigned long trans_timeout;
952 
953 	spin_lock_irq(&queue->_xmit_lock);
954 	trans_timeout = queue->trans_timeout;
955 	spin_unlock_irq(&queue->_xmit_lock);
956 
957 	return sprintf(buf, "%lu", trans_timeout);
958 }
959 
960 static struct netdev_queue_attribute queue_trans_timeout =
961 	__ATTR(tx_timeout, S_IRUGO, show_trans_timeout, NULL);
962 
963 #ifdef CONFIG_BQL
964 /*
965  * Byte queue limits sysfs structures and functions.
966  */
967 static ssize_t bql_show(char *buf, unsigned int value)
968 {
969 	return sprintf(buf, "%u\n", value);
970 }
971 
972 static ssize_t bql_set(const char *buf, const size_t count,
973 		       unsigned int *pvalue)
974 {
975 	unsigned int value;
976 	int err;
977 
978 	if (!strcmp(buf, "max") || !strcmp(buf, "max\n"))
979 		value = DQL_MAX_LIMIT;
980 	else {
981 		err = kstrtouint(buf, 10, &value);
982 		if (err < 0)
983 			return err;
984 		if (value > DQL_MAX_LIMIT)
985 			return -EINVAL;
986 	}
987 
988 	*pvalue = value;
989 
990 	return count;
991 }
992 
993 static ssize_t bql_show_hold_time(struct netdev_queue *queue,
994 				  struct netdev_queue_attribute *attr,
995 				  char *buf)
996 {
997 	struct dql *dql = &queue->dql;
998 
999 	return sprintf(buf, "%u\n", jiffies_to_msecs(dql->slack_hold_time));
1000 }
1001 
1002 static ssize_t bql_set_hold_time(struct netdev_queue *queue,
1003 				 struct netdev_queue_attribute *attribute,
1004 				 const char *buf, size_t len)
1005 {
1006 	struct dql *dql = &queue->dql;
1007 	unsigned int value;
1008 	int err;
1009 
1010 	err = kstrtouint(buf, 10, &value);
1011 	if (err < 0)
1012 		return err;
1013 
1014 	dql->slack_hold_time = msecs_to_jiffies(value);
1015 
1016 	return len;
1017 }
1018 
1019 static struct netdev_queue_attribute bql_hold_time_attribute =
1020 	__ATTR(hold_time, S_IRUGO | S_IWUSR, bql_show_hold_time,
1021 	    bql_set_hold_time);
1022 
1023 static ssize_t bql_show_inflight(struct netdev_queue *queue,
1024 				 struct netdev_queue_attribute *attr,
1025 				 char *buf)
1026 {
1027 	struct dql *dql = &queue->dql;
1028 
1029 	return sprintf(buf, "%u\n", dql->num_queued - dql->num_completed);
1030 }
1031 
1032 static struct netdev_queue_attribute bql_inflight_attribute =
1033 	__ATTR(inflight, S_IRUGO, bql_show_inflight, NULL);
1034 
1035 #define BQL_ATTR(NAME, FIELD)						\
1036 static ssize_t bql_show_ ## NAME(struct netdev_queue *queue,		\
1037 				 struct netdev_queue_attribute *attr,	\
1038 				 char *buf)				\
1039 {									\
1040 	return bql_show(buf, queue->dql.FIELD);				\
1041 }									\
1042 									\
1043 static ssize_t bql_set_ ## NAME(struct netdev_queue *queue,		\
1044 				struct netdev_queue_attribute *attr,	\
1045 				const char *buf, size_t len)		\
1046 {									\
1047 	return bql_set(buf, len, &queue->dql.FIELD);			\
1048 }									\
1049 									\
1050 static struct netdev_queue_attribute bql_ ## NAME ## _attribute =	\
1051 	__ATTR(NAME, S_IRUGO | S_IWUSR, bql_show_ ## NAME,		\
1052 	    bql_set_ ## NAME);
1053 
1054 BQL_ATTR(limit, limit)
1055 BQL_ATTR(limit_max, max_limit)
1056 BQL_ATTR(limit_min, min_limit)
1057 
1058 static struct attribute *dql_attrs[] = {
1059 	&bql_limit_attribute.attr,
1060 	&bql_limit_max_attribute.attr,
1061 	&bql_limit_min_attribute.attr,
1062 	&bql_hold_time_attribute.attr,
1063 	&bql_inflight_attribute.attr,
1064 	NULL
1065 };
1066 
1067 static struct attribute_group dql_group = {
1068 	.name  = "byte_queue_limits",
1069 	.attrs  = dql_attrs,
1070 };
1071 #endif /* CONFIG_BQL */
1072 
1073 #ifdef CONFIG_XPS
1074 static unsigned int get_netdev_queue_index(struct netdev_queue *queue)
1075 {
1076 	struct net_device *dev = queue->dev;
1077 	unsigned int i;
1078 
1079 	i = queue - dev->_tx;
1080 	BUG_ON(i >= dev->num_tx_queues);
1081 
1082 	return i;
1083 }
1084 
1085 
1086 static ssize_t show_xps_map(struct netdev_queue *queue,
1087 			    struct netdev_queue_attribute *attribute, char *buf)
1088 {
1089 	struct net_device *dev = queue->dev;
1090 	struct xps_dev_maps *dev_maps;
1091 	cpumask_var_t mask;
1092 	unsigned long index;
1093 	size_t len = 0;
1094 	int i;
1095 
1096 	if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
1097 		return -ENOMEM;
1098 
1099 	index = get_netdev_queue_index(queue);
1100 
1101 	rcu_read_lock();
1102 	dev_maps = rcu_dereference(dev->xps_maps);
1103 	if (dev_maps) {
1104 		for_each_possible_cpu(i) {
1105 			struct xps_map *map =
1106 			    rcu_dereference(dev_maps->cpu_map[i]);
1107 			if (map) {
1108 				int j;
1109 				for (j = 0; j < map->len; j++) {
1110 					if (map->queues[j] == index) {
1111 						cpumask_set_cpu(i, mask);
1112 						break;
1113 					}
1114 				}
1115 			}
1116 		}
1117 	}
1118 	rcu_read_unlock();
1119 
1120 	len += cpumask_scnprintf(buf + len, PAGE_SIZE, mask);
1121 	if (PAGE_SIZE - len < 3) {
1122 		free_cpumask_var(mask);
1123 		return -EINVAL;
1124 	}
1125 
1126 	free_cpumask_var(mask);
1127 	len += sprintf(buf + len, "\n");
1128 	return len;
1129 }
1130 
1131 static ssize_t store_xps_map(struct netdev_queue *queue,
1132 		      struct netdev_queue_attribute *attribute,
1133 		      const char *buf, size_t len)
1134 {
1135 	struct net_device *dev = queue->dev;
1136 	unsigned long index;
1137 	cpumask_var_t mask;
1138 	int err;
1139 
1140 	if (!capable(CAP_NET_ADMIN))
1141 		return -EPERM;
1142 
1143 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
1144 		return -ENOMEM;
1145 
1146 	index = get_netdev_queue_index(queue);
1147 
1148 	err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
1149 	if (err) {
1150 		free_cpumask_var(mask);
1151 		return err;
1152 	}
1153 
1154 	err = netif_set_xps_queue(dev, mask, index);
1155 
1156 	free_cpumask_var(mask);
1157 
1158 	return err ? : len;
1159 }
1160 
1161 static struct netdev_queue_attribute xps_cpus_attribute =
1162     __ATTR(xps_cpus, S_IRUGO | S_IWUSR, show_xps_map, store_xps_map);
1163 #endif /* CONFIG_XPS */
1164 
1165 static struct attribute *netdev_queue_default_attrs[] = {
1166 	&queue_trans_timeout.attr,
1167 #ifdef CONFIG_XPS
1168 	&xps_cpus_attribute.attr,
1169 #endif
1170 	NULL
1171 };
1172 
1173 static void netdev_queue_release(struct kobject *kobj)
1174 {
1175 	struct netdev_queue *queue = to_netdev_queue(kobj);
1176 
1177 	memset(kobj, 0, sizeof(*kobj));
1178 	dev_put(queue->dev);
1179 }
1180 
1181 static const void *netdev_queue_namespace(struct kobject *kobj)
1182 {
1183 	struct netdev_queue *queue = to_netdev_queue(kobj);
1184 	struct device *dev = &queue->dev->dev;
1185 	const void *ns = NULL;
1186 
1187 	if (dev->class && dev->class->ns_type)
1188 		ns = dev->class->namespace(dev);
1189 
1190 	return ns;
1191 }
1192 
1193 static struct kobj_type netdev_queue_ktype = {
1194 	.sysfs_ops = &netdev_queue_sysfs_ops,
1195 	.release = netdev_queue_release,
1196 	.default_attrs = netdev_queue_default_attrs,
1197 	.namespace = netdev_queue_namespace,
1198 };
1199 
1200 static int netdev_queue_add_kobject(struct net_device *dev, int index)
1201 {
1202 	struct netdev_queue *queue = dev->_tx + index;
1203 	struct kobject *kobj = &queue->kobj;
1204 	int error = 0;
1205 
1206 	kobj->kset = dev->queues_kset;
1207 	error = kobject_init_and_add(kobj, &netdev_queue_ktype, NULL,
1208 	    "tx-%u", index);
1209 	if (error)
1210 		goto exit;
1211 
1212 #ifdef CONFIG_BQL
1213 	error = sysfs_create_group(kobj, &dql_group);
1214 	if (error)
1215 		goto exit;
1216 #endif
1217 
1218 	kobject_uevent(kobj, KOBJ_ADD);
1219 	dev_hold(queue->dev);
1220 
1221 	return 0;
1222 exit:
1223 	kobject_put(kobj);
1224 	return error;
1225 }
1226 #endif /* CONFIG_SYSFS */
1227 
1228 int
1229 netdev_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
1230 {
1231 #ifdef CONFIG_SYSFS
1232 	int i;
1233 	int error = 0;
1234 
1235 	for (i = old_num; i < new_num; i++) {
1236 		error = netdev_queue_add_kobject(dev, i);
1237 		if (error) {
1238 			new_num = old_num;
1239 			break;
1240 		}
1241 	}
1242 
1243 	while (--i >= new_num) {
1244 		struct netdev_queue *queue = dev->_tx + i;
1245 
1246 #ifdef CONFIG_BQL
1247 		sysfs_remove_group(&queue->kobj, &dql_group);
1248 #endif
1249 		kobject_put(&queue->kobj);
1250 	}
1251 
1252 	return error;
1253 #else
1254 	return 0;
1255 #endif /* CONFIG_SYSFS */
1256 }
1257 
1258 static int register_queue_kobjects(struct net_device *dev)
1259 {
1260 	int error = 0, txq = 0, rxq = 0, real_rx = 0, real_tx = 0;
1261 
1262 #ifdef CONFIG_SYSFS
1263 	dev->queues_kset = kset_create_and_add("queues",
1264 	    NULL, &dev->dev.kobj);
1265 	if (!dev->queues_kset)
1266 		return -ENOMEM;
1267 	real_rx = dev->real_num_rx_queues;
1268 #endif
1269 	real_tx = dev->real_num_tx_queues;
1270 
1271 	error = net_rx_queue_update_kobjects(dev, 0, real_rx);
1272 	if (error)
1273 		goto error;
1274 	rxq = real_rx;
1275 
1276 	error = netdev_queue_update_kobjects(dev, 0, real_tx);
1277 	if (error)
1278 		goto error;
1279 	txq = real_tx;
1280 
1281 	return 0;
1282 
1283 error:
1284 	netdev_queue_update_kobjects(dev, txq, 0);
1285 	net_rx_queue_update_kobjects(dev, rxq, 0);
1286 	return error;
1287 }
1288 
1289 static void remove_queue_kobjects(struct net_device *dev)
1290 {
1291 	int real_rx = 0, real_tx = 0;
1292 
1293 #ifdef CONFIG_SYSFS
1294 	real_rx = dev->real_num_rx_queues;
1295 #endif
1296 	real_tx = dev->real_num_tx_queues;
1297 
1298 	net_rx_queue_update_kobjects(dev, real_rx, 0);
1299 	netdev_queue_update_kobjects(dev, real_tx, 0);
1300 #ifdef CONFIG_SYSFS
1301 	kset_unregister(dev->queues_kset);
1302 #endif
1303 }
1304 
1305 static bool net_current_may_mount(void)
1306 {
1307 	struct net *net = current->nsproxy->net_ns;
1308 
1309 	return ns_capable(net->user_ns, CAP_SYS_ADMIN);
1310 }
1311 
1312 static void *net_grab_current_ns(void)
1313 {
1314 	struct net *ns = current->nsproxy->net_ns;
1315 #ifdef CONFIG_NET_NS
1316 	if (ns)
1317 		atomic_inc(&ns->passive);
1318 #endif
1319 	return ns;
1320 }
1321 
1322 static const void *net_initial_ns(void)
1323 {
1324 	return &init_net;
1325 }
1326 
1327 static const void *net_netlink_ns(struct sock *sk)
1328 {
1329 	return sock_net(sk);
1330 }
1331 
1332 struct kobj_ns_type_operations net_ns_type_operations = {
1333 	.type = KOBJ_NS_TYPE_NET,
1334 	.current_may_mount = net_current_may_mount,
1335 	.grab_current_ns = net_grab_current_ns,
1336 	.netlink_ns = net_netlink_ns,
1337 	.initial_ns = net_initial_ns,
1338 	.drop_ns = net_drop_ns,
1339 };
1340 EXPORT_SYMBOL_GPL(net_ns_type_operations);
1341 
1342 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
1343 {
1344 	struct net_device *dev = to_net_dev(d);
1345 	int retval;
1346 
1347 	/* pass interface to uevent. */
1348 	retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
1349 	if (retval)
1350 		goto exit;
1351 
1352 	/* pass ifindex to uevent.
1353 	 * ifindex is useful as it won't change (interface name may change)
1354 	 * and is what RtNetlink uses natively. */
1355 	retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
1356 
1357 exit:
1358 	return retval;
1359 }
1360 
1361 /*
1362  *	netdev_release -- destroy and free a dead device.
1363  *	Called when last reference to device kobject is gone.
1364  */
1365 static void netdev_release(struct device *d)
1366 {
1367 	struct net_device *dev = to_net_dev(d);
1368 
1369 	BUG_ON(dev->reg_state != NETREG_RELEASED);
1370 
1371 	kfree(dev->ifalias);
1372 	netdev_freemem(dev);
1373 }
1374 
1375 static const void *net_namespace(struct device *d)
1376 {
1377 	struct net_device *dev;
1378 	dev = container_of(d, struct net_device, dev);
1379 	return dev_net(dev);
1380 }
1381 
1382 static struct class net_class = {
1383 	.name = "net",
1384 	.dev_release = netdev_release,
1385 	.dev_groups = net_class_groups,
1386 	.dev_uevent = netdev_uevent,
1387 	.ns_type = &net_ns_type_operations,
1388 	.namespace = net_namespace,
1389 };
1390 
1391 /* Delete sysfs entries but hold kobject reference until after all
1392  * netdev references are gone.
1393  */
1394 void netdev_unregister_kobject(struct net_device *ndev)
1395 {
1396 	struct device *dev = &(ndev->dev);
1397 
1398 	kobject_get(&dev->kobj);
1399 
1400 	remove_queue_kobjects(ndev);
1401 
1402 	pm_runtime_set_memalloc_noio(dev, false);
1403 
1404 	device_del(dev);
1405 }
1406 
1407 /* Create sysfs entries for network device. */
1408 int netdev_register_kobject(struct net_device *ndev)
1409 {
1410 	struct device *dev = &(ndev->dev);
1411 	const struct attribute_group **groups = ndev->sysfs_groups;
1412 	int error = 0;
1413 
1414 	device_initialize(dev);
1415 	dev->class = &net_class;
1416 	dev->platform_data = ndev;
1417 	dev->groups = groups;
1418 
1419 	dev_set_name(dev, "%s", ndev->name);
1420 
1421 #ifdef CONFIG_SYSFS
1422 	/* Allow for a device specific group */
1423 	if (*groups)
1424 		groups++;
1425 
1426 	*groups++ = &netstat_group;
1427 
1428 #if IS_ENABLED(CONFIG_WIRELESS_EXT) || IS_ENABLED(CONFIG_CFG80211)
1429 	if (ndev->ieee80211_ptr)
1430 		*groups++ = &wireless_group;
1431 #if IS_ENABLED(CONFIG_WIRELESS_EXT)
1432 	else if (ndev->wireless_handlers)
1433 		*groups++ = &wireless_group;
1434 #endif
1435 #endif
1436 #endif /* CONFIG_SYSFS */
1437 
1438 	error = device_add(dev);
1439 	if (error)
1440 		return error;
1441 
1442 	error = register_queue_kobjects(ndev);
1443 	if (error) {
1444 		device_del(dev);
1445 		return error;
1446 	}
1447 
1448 	pm_runtime_set_memalloc_noio(dev, true);
1449 
1450 	return error;
1451 }
1452 
1453 int netdev_class_create_file_ns(struct class_attribute *class_attr,
1454 				const void *ns)
1455 {
1456 	return class_create_file_ns(&net_class, class_attr, ns);
1457 }
1458 EXPORT_SYMBOL(netdev_class_create_file_ns);
1459 
1460 void netdev_class_remove_file_ns(struct class_attribute *class_attr,
1461 				 const void *ns)
1462 {
1463 	class_remove_file_ns(&net_class, class_attr, ns);
1464 }
1465 EXPORT_SYMBOL(netdev_class_remove_file_ns);
1466 
1467 int __init netdev_kobject_init(void)
1468 {
1469 	kobj_ns_type_register(&net_ns_type_operations);
1470 	return class_register(&net_class);
1471 }
1472