xref: /openbmc/linux/net/core/net-sysfs.c (revision c1d45424)
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 <linux/if_arp.h>
16 #include <linux/slab.h>
17 #include <linux/nsproxy.h>
18 #include <net/sock.h>
19 #include <net/net_namespace.h>
20 #include <linux/rtnetlink.h>
21 #include <linux/vmalloc.h>
22 #include <linux/export.h>
23 #include <linux/jiffies.h>
24 #include <linux/pm_runtime.h>
25 
26 #include "net-sysfs.h"
27 
28 #ifdef CONFIG_SYSFS
29 static const char fmt_hex[] = "%#x\n";
30 static const char fmt_long_hex[] = "%#lx\n";
31 static const char fmt_dec[] = "%d\n";
32 static const char fmt_udec[] = "%u\n";
33 static const char fmt_ulong[] = "%lu\n";
34 static const char fmt_u64[] = "%llu\n";
35 
36 static inline int dev_isalive(const struct net_device *dev)
37 {
38 	return dev->reg_state <= NETREG_REGISTERED;
39 }
40 
41 /* use same locking rules as GIF* ioctl's */
42 static ssize_t netdev_show(const struct device *dev,
43 			   struct device_attribute *attr, char *buf,
44 			   ssize_t (*format)(const struct net_device *, char *))
45 {
46 	struct net_device *net = to_net_dev(dev);
47 	ssize_t ret = -EINVAL;
48 
49 	read_lock(&dev_base_lock);
50 	if (dev_isalive(net))
51 		ret = (*format)(net, buf);
52 	read_unlock(&dev_base_lock);
53 
54 	return ret;
55 }
56 
57 /* generate a show function for simple field */
58 #define NETDEVICE_SHOW(field, format_string)				\
59 static ssize_t format_##field(const struct net_device *net, char *buf)	\
60 {									\
61 	return sprintf(buf, format_string, net->field);			\
62 }									\
63 static ssize_t show_##field(struct device *dev,				\
64 			    struct device_attribute *attr, char *buf)	\
65 {									\
66 	return netdev_show(dev, attr, buf, format_##field);		\
67 }
68 
69 
70 /* use same locking and permission rules as SIF* ioctl's */
71 static ssize_t netdev_store(struct device *dev, struct device_attribute *attr,
72 			    const char *buf, size_t len,
73 			    int (*set)(struct net_device *, unsigned long))
74 {
75 	struct net_device *netdev = to_net_dev(dev);
76 	struct net *net = dev_net(netdev);
77 	unsigned long new;
78 	int ret = -EINVAL;
79 
80 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
81 		return -EPERM;
82 
83 	ret = kstrtoul(buf, 0, &new);
84 	if (ret)
85 		goto err;
86 
87 	if (!rtnl_trylock())
88 		return restart_syscall();
89 
90 	if (dev_isalive(netdev)) {
91 		if ((ret = (*set)(netdev, new)) == 0)
92 			ret = len;
93 	}
94 	rtnl_unlock();
95  err:
96 	return ret;
97 }
98 
99 NETDEVICE_SHOW(dev_id, fmt_hex);
100 NETDEVICE_SHOW(addr_assign_type, fmt_dec);
101 NETDEVICE_SHOW(addr_len, fmt_dec);
102 NETDEVICE_SHOW(iflink, fmt_dec);
103 NETDEVICE_SHOW(ifindex, fmt_dec);
104 NETDEVICE_SHOW(type, fmt_dec);
105 NETDEVICE_SHOW(link_mode, fmt_dec);
106 
107 /* use same locking rules as GIFHWADDR ioctl's */
108 static ssize_t show_address(struct device *dev, struct device_attribute *attr,
109 			    char *buf)
110 {
111 	struct net_device *net = to_net_dev(dev);
112 	ssize_t ret = -EINVAL;
113 
114 	read_lock(&dev_base_lock);
115 	if (dev_isalive(net))
116 		ret = sysfs_format_mac(buf, net->dev_addr, net->addr_len);
117 	read_unlock(&dev_base_lock);
118 	return ret;
119 }
120 
121 static ssize_t show_broadcast(struct device *dev,
122 			    struct device_attribute *attr, char *buf)
123 {
124 	struct net_device *net = to_net_dev(dev);
125 	if (dev_isalive(net))
126 		return sysfs_format_mac(buf, net->broadcast, net->addr_len);
127 	return -EINVAL;
128 }
129 
130 static int change_carrier(struct net_device *net, unsigned long new_carrier)
131 {
132 	if (!netif_running(net))
133 		return -EINVAL;
134 	return dev_change_carrier(net, (bool) new_carrier);
135 }
136 
137 static ssize_t store_carrier(struct device *dev, struct device_attribute *attr,
138 			 const char *buf, size_t len)
139 {
140 	return netdev_store(dev, attr, buf, len, change_carrier);
141 }
142 
143 static ssize_t show_carrier(struct device *dev,
144 			    struct device_attribute *attr, char *buf)
145 {
146 	struct net_device *netdev = to_net_dev(dev);
147 	if (netif_running(netdev)) {
148 		return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
149 	}
150 	return -EINVAL;
151 }
152 
153 static ssize_t show_speed(struct device *dev,
154 			  struct device_attribute *attr, char *buf)
155 {
156 	struct net_device *netdev = to_net_dev(dev);
157 	int ret = -EINVAL;
158 
159 	if (!rtnl_trylock())
160 		return restart_syscall();
161 
162 	if (netif_running(netdev)) {
163 		struct ethtool_cmd cmd;
164 		if (!__ethtool_get_settings(netdev, &cmd))
165 			ret = sprintf(buf, fmt_udec, ethtool_cmd_speed(&cmd));
166 	}
167 	rtnl_unlock();
168 	return ret;
169 }
170 
171 static ssize_t show_duplex(struct device *dev,
172 			   struct device_attribute *attr, char *buf)
173 {
174 	struct net_device *netdev = to_net_dev(dev);
175 	int ret = -EINVAL;
176 
177 	if (!rtnl_trylock())
178 		return restart_syscall();
179 
180 	if (netif_running(netdev)) {
181 		struct ethtool_cmd cmd;
182 		if (!__ethtool_get_settings(netdev, &cmd)) {
183 			const char *duplex;
184 			switch (cmd.duplex) {
185 			case DUPLEX_HALF:
186 				duplex = "half";
187 				break;
188 			case DUPLEX_FULL:
189 				duplex = "full";
190 				break;
191 			default:
192 				duplex = "unknown";
193 				break;
194 			}
195 			ret = sprintf(buf, "%s\n", duplex);
196 		}
197 	}
198 	rtnl_unlock();
199 	return ret;
200 }
201 
202 static ssize_t show_dormant(struct device *dev,
203 			    struct device_attribute *attr, char *buf)
204 {
205 	struct net_device *netdev = to_net_dev(dev);
206 
207 	if (netif_running(netdev))
208 		return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
209 
210 	return -EINVAL;
211 }
212 
213 static const char *const operstates[] = {
214 	"unknown",
215 	"notpresent", /* currently unused */
216 	"down",
217 	"lowerlayerdown",
218 	"testing", /* currently unused */
219 	"dormant",
220 	"up"
221 };
222 
223 static ssize_t show_operstate(struct device *dev,
224 			      struct device_attribute *attr, char *buf)
225 {
226 	const struct net_device *netdev = to_net_dev(dev);
227 	unsigned char operstate;
228 
229 	read_lock(&dev_base_lock);
230 	operstate = netdev->operstate;
231 	if (!netif_running(netdev))
232 		operstate = IF_OPER_DOWN;
233 	read_unlock(&dev_base_lock);
234 
235 	if (operstate >= ARRAY_SIZE(operstates))
236 		return -EINVAL; /* should not happen */
237 
238 	return sprintf(buf, "%s\n", operstates[operstate]);
239 }
240 
241 /* read-write attributes */
242 NETDEVICE_SHOW(mtu, fmt_dec);
243 
244 static int change_mtu(struct net_device *net, unsigned long new_mtu)
245 {
246 	return dev_set_mtu(net, (int) new_mtu);
247 }
248 
249 static ssize_t store_mtu(struct device *dev, struct device_attribute *attr,
250 			 const char *buf, size_t len)
251 {
252 	return netdev_store(dev, attr, buf, len, change_mtu);
253 }
254 
255 NETDEVICE_SHOW(flags, fmt_hex);
256 
257 static int change_flags(struct net_device *net, unsigned long new_flags)
258 {
259 	return dev_change_flags(net, (unsigned int) new_flags);
260 }
261 
262 static ssize_t store_flags(struct device *dev, struct device_attribute *attr,
263 			   const char *buf, size_t len)
264 {
265 	return netdev_store(dev, attr, buf, len, change_flags);
266 }
267 
268 NETDEVICE_SHOW(tx_queue_len, fmt_ulong);
269 
270 static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
271 {
272 	net->tx_queue_len = new_len;
273 	return 0;
274 }
275 
276 static ssize_t store_tx_queue_len(struct device *dev,
277 				  struct device_attribute *attr,
278 				  const char *buf, size_t len)
279 {
280 	if (!capable(CAP_NET_ADMIN))
281 		return -EPERM;
282 
283 	return netdev_store(dev, attr, buf, len, change_tx_queue_len);
284 }
285 
286 static ssize_t store_ifalias(struct device *dev, struct device_attribute *attr,
287 			     const char *buf, size_t len)
288 {
289 	struct net_device *netdev = to_net_dev(dev);
290 	struct net *net = dev_net(netdev);
291 	size_t count = len;
292 	ssize_t ret;
293 
294 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
295 		return -EPERM;
296 
297 	/* ignore trailing newline */
298 	if (len >  0 && buf[len - 1] == '\n')
299 		--count;
300 
301 	if (!rtnl_trylock())
302 		return restart_syscall();
303 	ret = dev_set_alias(netdev, buf, count);
304 	rtnl_unlock();
305 
306 	return ret < 0 ? ret : len;
307 }
308 
309 static ssize_t show_ifalias(struct device *dev,
310 			    struct device_attribute *attr, char *buf)
311 {
312 	const struct net_device *netdev = to_net_dev(dev);
313 	ssize_t ret = 0;
314 
315 	if (!rtnl_trylock())
316 		return restart_syscall();
317 	if (netdev->ifalias)
318 		ret = sprintf(buf, "%s\n", netdev->ifalias);
319 	rtnl_unlock();
320 	return ret;
321 }
322 
323 NETDEVICE_SHOW(group, fmt_dec);
324 
325 static int change_group(struct net_device *net, unsigned long new_group)
326 {
327 	dev_set_group(net, (int) new_group);
328 	return 0;
329 }
330 
331 static ssize_t store_group(struct device *dev, struct device_attribute *attr,
332 			 const char *buf, size_t len)
333 {
334 	return netdev_store(dev, attr, buf, len, change_group);
335 }
336 
337 static struct device_attribute net_class_attributes[] = {
338 	__ATTR(addr_assign_type, S_IRUGO, show_addr_assign_type, NULL),
339 	__ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
340 	__ATTR(dev_id, S_IRUGO, show_dev_id, NULL),
341 	__ATTR(ifalias, S_IRUGO | S_IWUSR, show_ifalias, store_ifalias),
342 	__ATTR(iflink, S_IRUGO, show_iflink, NULL),
343 	__ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
344 	__ATTR(type, S_IRUGO, show_type, NULL),
345 	__ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
346 	__ATTR(address, S_IRUGO, show_address, NULL),
347 	__ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
348 	__ATTR(carrier, S_IRUGO | S_IWUSR, show_carrier, store_carrier),
349 	__ATTR(speed, S_IRUGO, show_speed, NULL),
350 	__ATTR(duplex, S_IRUGO, show_duplex, NULL),
351 	__ATTR(dormant, S_IRUGO, show_dormant, NULL),
352 	__ATTR(operstate, S_IRUGO, show_operstate, NULL),
353 	__ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
354 	__ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
355 	__ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
356 	       store_tx_queue_len),
357 	__ATTR(netdev_group, S_IRUGO | S_IWUSR, show_group, store_group),
358 	{}
359 };
360 
361 /* Show a given an attribute in the statistics group */
362 static ssize_t netstat_show(const struct device *d,
363 			    struct device_attribute *attr, char *buf,
364 			    unsigned long offset)
365 {
366 	struct net_device *dev = to_net_dev(d);
367 	ssize_t ret = -EINVAL;
368 
369 	WARN_ON(offset > sizeof(struct rtnl_link_stats64) ||
370 			offset % sizeof(u64) != 0);
371 
372 	read_lock(&dev_base_lock);
373 	if (dev_isalive(dev)) {
374 		struct rtnl_link_stats64 temp;
375 		const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
376 
377 		ret = sprintf(buf, fmt_u64, *(u64 *)(((u8 *) stats) + offset));
378 	}
379 	read_unlock(&dev_base_lock);
380 	return ret;
381 }
382 
383 /* generate a read-only statistics attribute */
384 #define NETSTAT_ENTRY(name)						\
385 static ssize_t show_##name(struct device *d,				\
386 			   struct device_attribute *attr, char *buf) 	\
387 {									\
388 	return netstat_show(d, attr, buf,				\
389 			    offsetof(struct rtnl_link_stats64, name));	\
390 }									\
391 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
392 
393 NETSTAT_ENTRY(rx_packets);
394 NETSTAT_ENTRY(tx_packets);
395 NETSTAT_ENTRY(rx_bytes);
396 NETSTAT_ENTRY(tx_bytes);
397 NETSTAT_ENTRY(rx_errors);
398 NETSTAT_ENTRY(tx_errors);
399 NETSTAT_ENTRY(rx_dropped);
400 NETSTAT_ENTRY(tx_dropped);
401 NETSTAT_ENTRY(multicast);
402 NETSTAT_ENTRY(collisions);
403 NETSTAT_ENTRY(rx_length_errors);
404 NETSTAT_ENTRY(rx_over_errors);
405 NETSTAT_ENTRY(rx_crc_errors);
406 NETSTAT_ENTRY(rx_frame_errors);
407 NETSTAT_ENTRY(rx_fifo_errors);
408 NETSTAT_ENTRY(rx_missed_errors);
409 NETSTAT_ENTRY(tx_aborted_errors);
410 NETSTAT_ENTRY(tx_carrier_errors);
411 NETSTAT_ENTRY(tx_fifo_errors);
412 NETSTAT_ENTRY(tx_heartbeat_errors);
413 NETSTAT_ENTRY(tx_window_errors);
414 NETSTAT_ENTRY(rx_compressed);
415 NETSTAT_ENTRY(tx_compressed);
416 
417 static struct attribute *netstat_attrs[] = {
418 	&dev_attr_rx_packets.attr,
419 	&dev_attr_tx_packets.attr,
420 	&dev_attr_rx_bytes.attr,
421 	&dev_attr_tx_bytes.attr,
422 	&dev_attr_rx_errors.attr,
423 	&dev_attr_tx_errors.attr,
424 	&dev_attr_rx_dropped.attr,
425 	&dev_attr_tx_dropped.attr,
426 	&dev_attr_multicast.attr,
427 	&dev_attr_collisions.attr,
428 	&dev_attr_rx_length_errors.attr,
429 	&dev_attr_rx_over_errors.attr,
430 	&dev_attr_rx_crc_errors.attr,
431 	&dev_attr_rx_frame_errors.attr,
432 	&dev_attr_rx_fifo_errors.attr,
433 	&dev_attr_rx_missed_errors.attr,
434 	&dev_attr_tx_aborted_errors.attr,
435 	&dev_attr_tx_carrier_errors.attr,
436 	&dev_attr_tx_fifo_errors.attr,
437 	&dev_attr_tx_heartbeat_errors.attr,
438 	&dev_attr_tx_window_errors.attr,
439 	&dev_attr_rx_compressed.attr,
440 	&dev_attr_tx_compressed.attr,
441 	NULL
442 };
443 
444 
445 static struct attribute_group netstat_group = {
446 	.name  = "statistics",
447 	.attrs  = netstat_attrs,
448 };
449 
450 #if IS_ENABLED(CONFIG_WIRELESS_EXT) || IS_ENABLED(CONFIG_CFG80211)
451 static struct attribute *wireless_attrs[] = {
452 	NULL
453 };
454 
455 static struct attribute_group wireless_group = {
456 	.name = "wireless",
457 	.attrs = wireless_attrs,
458 };
459 #endif
460 #endif /* CONFIG_SYSFS */
461 
462 #ifdef CONFIG_RPS
463 /*
464  * RX queue sysfs structures and functions.
465  */
466 struct rx_queue_attribute {
467 	struct attribute attr;
468 	ssize_t (*show)(struct netdev_rx_queue *queue,
469 	    struct rx_queue_attribute *attr, char *buf);
470 	ssize_t (*store)(struct netdev_rx_queue *queue,
471 	    struct rx_queue_attribute *attr, const char *buf, size_t len);
472 };
473 #define to_rx_queue_attr(_attr) container_of(_attr,		\
474     struct rx_queue_attribute, attr)
475 
476 #define to_rx_queue(obj) container_of(obj, struct netdev_rx_queue, kobj)
477 
478 static ssize_t rx_queue_attr_show(struct kobject *kobj, struct attribute *attr,
479 				  char *buf)
480 {
481 	struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
482 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
483 
484 	if (!attribute->show)
485 		return -EIO;
486 
487 	return attribute->show(queue, attribute, buf);
488 }
489 
490 static ssize_t rx_queue_attr_store(struct kobject *kobj, struct attribute *attr,
491 				   const char *buf, size_t count)
492 {
493 	struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
494 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
495 
496 	if (!attribute->store)
497 		return -EIO;
498 
499 	return attribute->store(queue, attribute, buf, count);
500 }
501 
502 static const struct sysfs_ops rx_queue_sysfs_ops = {
503 	.show = rx_queue_attr_show,
504 	.store = rx_queue_attr_store,
505 };
506 
507 static ssize_t show_rps_map(struct netdev_rx_queue *queue,
508 			    struct rx_queue_attribute *attribute, char *buf)
509 {
510 	struct rps_map *map;
511 	cpumask_var_t mask;
512 	size_t len = 0;
513 	int i;
514 
515 	if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
516 		return -ENOMEM;
517 
518 	rcu_read_lock();
519 	map = rcu_dereference(queue->rps_map);
520 	if (map)
521 		for (i = 0; i < map->len; i++)
522 			cpumask_set_cpu(map->cpus[i], mask);
523 
524 	len += cpumask_scnprintf(buf + len, PAGE_SIZE, mask);
525 	if (PAGE_SIZE - len < 3) {
526 		rcu_read_unlock();
527 		free_cpumask_var(mask);
528 		return -EINVAL;
529 	}
530 	rcu_read_unlock();
531 
532 	free_cpumask_var(mask);
533 	len += sprintf(buf + len, "\n");
534 	return len;
535 }
536 
537 static ssize_t store_rps_map(struct netdev_rx_queue *queue,
538 		      struct rx_queue_attribute *attribute,
539 		      const char *buf, size_t len)
540 {
541 	struct rps_map *old_map, *map;
542 	cpumask_var_t mask;
543 	int err, cpu, i;
544 	static DEFINE_SPINLOCK(rps_map_lock);
545 
546 	if (!capable(CAP_NET_ADMIN))
547 		return -EPERM;
548 
549 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
550 		return -ENOMEM;
551 
552 	err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
553 	if (err) {
554 		free_cpumask_var(mask);
555 		return err;
556 	}
557 
558 	map = kzalloc(max_t(unsigned int,
559 	    RPS_MAP_SIZE(cpumask_weight(mask)), L1_CACHE_BYTES),
560 	    GFP_KERNEL);
561 	if (!map) {
562 		free_cpumask_var(mask);
563 		return -ENOMEM;
564 	}
565 
566 	i = 0;
567 	for_each_cpu_and(cpu, mask, cpu_online_mask)
568 		map->cpus[i++] = cpu;
569 
570 	if (i)
571 		map->len = i;
572 	else {
573 		kfree(map);
574 		map = NULL;
575 	}
576 
577 	spin_lock(&rps_map_lock);
578 	old_map = rcu_dereference_protected(queue->rps_map,
579 					    lockdep_is_held(&rps_map_lock));
580 	rcu_assign_pointer(queue->rps_map, map);
581 	spin_unlock(&rps_map_lock);
582 
583 	if (map)
584 		static_key_slow_inc(&rps_needed);
585 	if (old_map) {
586 		kfree_rcu(old_map, rcu);
587 		static_key_slow_dec(&rps_needed);
588 	}
589 	free_cpumask_var(mask);
590 	return len;
591 }
592 
593 static ssize_t show_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
594 					   struct rx_queue_attribute *attr,
595 					   char *buf)
596 {
597 	struct rps_dev_flow_table *flow_table;
598 	unsigned long val = 0;
599 
600 	rcu_read_lock();
601 	flow_table = rcu_dereference(queue->rps_flow_table);
602 	if (flow_table)
603 		val = (unsigned long)flow_table->mask + 1;
604 	rcu_read_unlock();
605 
606 	return sprintf(buf, "%lu\n", val);
607 }
608 
609 static void rps_dev_flow_table_release(struct rcu_head *rcu)
610 {
611 	struct rps_dev_flow_table *table = container_of(rcu,
612 	    struct rps_dev_flow_table, rcu);
613 	vfree(table);
614 }
615 
616 static ssize_t store_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
617 				     struct rx_queue_attribute *attr,
618 				     const char *buf, size_t len)
619 {
620 	unsigned long mask, count;
621 	struct rps_dev_flow_table *table, *old_table;
622 	static DEFINE_SPINLOCK(rps_dev_flow_lock);
623 	int rc;
624 
625 	if (!capable(CAP_NET_ADMIN))
626 		return -EPERM;
627 
628 	rc = kstrtoul(buf, 0, &count);
629 	if (rc < 0)
630 		return rc;
631 
632 	if (count) {
633 		mask = count - 1;
634 		/* mask = roundup_pow_of_two(count) - 1;
635 		 * without overflows...
636 		 */
637 		while ((mask | (mask >> 1)) != mask)
638 			mask |= (mask >> 1);
639 		/* On 64 bit arches, must check mask fits in table->mask (u32),
640 		 * and on 32bit arches, must check RPS_DEV_FLOW_TABLE_SIZE(mask + 1)
641 		 * doesnt overflow.
642 		 */
643 #if BITS_PER_LONG > 32
644 		if (mask > (unsigned long)(u32)mask)
645 			return -EINVAL;
646 #else
647 		if (mask > (ULONG_MAX - RPS_DEV_FLOW_TABLE_SIZE(1))
648 				/ sizeof(struct rps_dev_flow)) {
649 			/* Enforce a limit to prevent overflow */
650 			return -EINVAL;
651 		}
652 #endif
653 		table = vmalloc(RPS_DEV_FLOW_TABLE_SIZE(mask + 1));
654 		if (!table)
655 			return -ENOMEM;
656 
657 		table->mask = mask;
658 		for (count = 0; count <= mask; count++)
659 			table->flows[count].cpu = RPS_NO_CPU;
660 	} else
661 		table = NULL;
662 
663 	spin_lock(&rps_dev_flow_lock);
664 	old_table = rcu_dereference_protected(queue->rps_flow_table,
665 					      lockdep_is_held(&rps_dev_flow_lock));
666 	rcu_assign_pointer(queue->rps_flow_table, table);
667 	spin_unlock(&rps_dev_flow_lock);
668 
669 	if (old_table)
670 		call_rcu(&old_table->rcu, rps_dev_flow_table_release);
671 
672 	return len;
673 }
674 
675 static struct rx_queue_attribute rps_cpus_attribute =
676 	__ATTR(rps_cpus, S_IRUGO | S_IWUSR, show_rps_map, store_rps_map);
677 
678 
679 static struct rx_queue_attribute rps_dev_flow_table_cnt_attribute =
680 	__ATTR(rps_flow_cnt, S_IRUGO | S_IWUSR,
681 	    show_rps_dev_flow_table_cnt, store_rps_dev_flow_table_cnt);
682 
683 static struct attribute *rx_queue_default_attrs[] = {
684 	&rps_cpus_attribute.attr,
685 	&rps_dev_flow_table_cnt_attribute.attr,
686 	NULL
687 };
688 
689 static void rx_queue_release(struct kobject *kobj)
690 {
691 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
692 	struct rps_map *map;
693 	struct rps_dev_flow_table *flow_table;
694 
695 
696 	map = rcu_dereference_protected(queue->rps_map, 1);
697 	if (map) {
698 		RCU_INIT_POINTER(queue->rps_map, NULL);
699 		kfree_rcu(map, rcu);
700 	}
701 
702 	flow_table = rcu_dereference_protected(queue->rps_flow_table, 1);
703 	if (flow_table) {
704 		RCU_INIT_POINTER(queue->rps_flow_table, NULL);
705 		call_rcu(&flow_table->rcu, rps_dev_flow_table_release);
706 	}
707 
708 	memset(kobj, 0, sizeof(*kobj));
709 	dev_put(queue->dev);
710 }
711 
712 static struct kobj_type rx_queue_ktype = {
713 	.sysfs_ops = &rx_queue_sysfs_ops,
714 	.release = rx_queue_release,
715 	.default_attrs = rx_queue_default_attrs,
716 };
717 
718 static int rx_queue_add_kobject(struct net_device *net, int index)
719 {
720 	struct netdev_rx_queue *queue = net->_rx + index;
721 	struct kobject *kobj = &queue->kobj;
722 	int error = 0;
723 
724 	kobj->kset = net->queues_kset;
725 	error = kobject_init_and_add(kobj, &rx_queue_ktype, NULL,
726 	    "rx-%u", index);
727 	if (error) {
728 		kobject_put(kobj);
729 		return error;
730 	}
731 
732 	kobject_uevent(kobj, KOBJ_ADD);
733 	dev_hold(queue->dev);
734 
735 	return error;
736 }
737 #endif /* CONFIG_RPS */
738 
739 int
740 net_rx_queue_update_kobjects(struct net_device *net, int old_num, int new_num)
741 {
742 #ifdef CONFIG_RPS
743 	int i;
744 	int error = 0;
745 
746 	for (i = old_num; i < new_num; i++) {
747 		error = rx_queue_add_kobject(net, i);
748 		if (error) {
749 			new_num = old_num;
750 			break;
751 		}
752 	}
753 
754 	while (--i >= new_num)
755 		kobject_put(&net->_rx[i].kobj);
756 
757 	return error;
758 #else
759 	return 0;
760 #endif
761 }
762 
763 #ifdef CONFIG_SYSFS
764 /*
765  * netdev_queue sysfs structures and functions.
766  */
767 struct netdev_queue_attribute {
768 	struct attribute attr;
769 	ssize_t (*show)(struct netdev_queue *queue,
770 	    struct netdev_queue_attribute *attr, char *buf);
771 	ssize_t (*store)(struct netdev_queue *queue,
772 	    struct netdev_queue_attribute *attr, const char *buf, size_t len);
773 };
774 #define to_netdev_queue_attr(_attr) container_of(_attr,		\
775     struct netdev_queue_attribute, attr)
776 
777 #define to_netdev_queue(obj) container_of(obj, struct netdev_queue, kobj)
778 
779 static ssize_t netdev_queue_attr_show(struct kobject *kobj,
780 				      struct attribute *attr, char *buf)
781 {
782 	struct netdev_queue_attribute *attribute = to_netdev_queue_attr(attr);
783 	struct netdev_queue *queue = to_netdev_queue(kobj);
784 
785 	if (!attribute->show)
786 		return -EIO;
787 
788 	return attribute->show(queue, attribute, buf);
789 }
790 
791 static ssize_t netdev_queue_attr_store(struct kobject *kobj,
792 				       struct attribute *attr,
793 				       const char *buf, size_t count)
794 {
795 	struct netdev_queue_attribute *attribute = to_netdev_queue_attr(attr);
796 	struct netdev_queue *queue = to_netdev_queue(kobj);
797 
798 	if (!attribute->store)
799 		return -EIO;
800 
801 	return attribute->store(queue, attribute, buf, count);
802 }
803 
804 static const struct sysfs_ops netdev_queue_sysfs_ops = {
805 	.show = netdev_queue_attr_show,
806 	.store = netdev_queue_attr_store,
807 };
808 
809 static ssize_t show_trans_timeout(struct netdev_queue *queue,
810 				  struct netdev_queue_attribute *attribute,
811 				  char *buf)
812 {
813 	unsigned long trans_timeout;
814 
815 	spin_lock_irq(&queue->_xmit_lock);
816 	trans_timeout = queue->trans_timeout;
817 	spin_unlock_irq(&queue->_xmit_lock);
818 
819 	return sprintf(buf, "%lu", trans_timeout);
820 }
821 
822 static struct netdev_queue_attribute queue_trans_timeout =
823 	__ATTR(tx_timeout, S_IRUGO, show_trans_timeout, NULL);
824 
825 #ifdef CONFIG_BQL
826 /*
827  * Byte queue limits sysfs structures and functions.
828  */
829 static ssize_t bql_show(char *buf, unsigned int value)
830 {
831 	return sprintf(buf, "%u\n", value);
832 }
833 
834 static ssize_t bql_set(const char *buf, const size_t count,
835 		       unsigned int *pvalue)
836 {
837 	unsigned int value;
838 	int err;
839 
840 	if (!strcmp(buf, "max") || !strcmp(buf, "max\n"))
841 		value = DQL_MAX_LIMIT;
842 	else {
843 		err = kstrtouint(buf, 10, &value);
844 		if (err < 0)
845 			return err;
846 		if (value > DQL_MAX_LIMIT)
847 			return -EINVAL;
848 	}
849 
850 	*pvalue = value;
851 
852 	return count;
853 }
854 
855 static ssize_t bql_show_hold_time(struct netdev_queue *queue,
856 				  struct netdev_queue_attribute *attr,
857 				  char *buf)
858 {
859 	struct dql *dql = &queue->dql;
860 
861 	return sprintf(buf, "%u\n", jiffies_to_msecs(dql->slack_hold_time));
862 }
863 
864 static ssize_t bql_set_hold_time(struct netdev_queue *queue,
865 				 struct netdev_queue_attribute *attribute,
866 				 const char *buf, size_t len)
867 {
868 	struct dql *dql = &queue->dql;
869 	unsigned int value;
870 	int err;
871 
872 	err = kstrtouint(buf, 10, &value);
873 	if (err < 0)
874 		return err;
875 
876 	dql->slack_hold_time = msecs_to_jiffies(value);
877 
878 	return len;
879 }
880 
881 static struct netdev_queue_attribute bql_hold_time_attribute =
882 	__ATTR(hold_time, S_IRUGO | S_IWUSR, bql_show_hold_time,
883 	    bql_set_hold_time);
884 
885 static ssize_t bql_show_inflight(struct netdev_queue *queue,
886 				 struct netdev_queue_attribute *attr,
887 				 char *buf)
888 {
889 	struct dql *dql = &queue->dql;
890 
891 	return sprintf(buf, "%u\n", dql->num_queued - dql->num_completed);
892 }
893 
894 static struct netdev_queue_attribute bql_inflight_attribute =
895 	__ATTR(inflight, S_IRUGO, bql_show_inflight, NULL);
896 
897 #define BQL_ATTR(NAME, FIELD)						\
898 static ssize_t bql_show_ ## NAME(struct netdev_queue *queue,		\
899 				 struct netdev_queue_attribute *attr,	\
900 				 char *buf)				\
901 {									\
902 	return bql_show(buf, queue->dql.FIELD);				\
903 }									\
904 									\
905 static ssize_t bql_set_ ## NAME(struct netdev_queue *queue,		\
906 				struct netdev_queue_attribute *attr,	\
907 				const char *buf, size_t len)		\
908 {									\
909 	return bql_set(buf, len, &queue->dql.FIELD);			\
910 }									\
911 									\
912 static struct netdev_queue_attribute bql_ ## NAME ## _attribute =	\
913 	__ATTR(NAME, S_IRUGO | S_IWUSR, bql_show_ ## NAME,		\
914 	    bql_set_ ## NAME);
915 
916 BQL_ATTR(limit, limit)
917 BQL_ATTR(limit_max, max_limit)
918 BQL_ATTR(limit_min, min_limit)
919 
920 static struct attribute *dql_attrs[] = {
921 	&bql_limit_attribute.attr,
922 	&bql_limit_max_attribute.attr,
923 	&bql_limit_min_attribute.attr,
924 	&bql_hold_time_attribute.attr,
925 	&bql_inflight_attribute.attr,
926 	NULL
927 };
928 
929 static struct attribute_group dql_group = {
930 	.name  = "byte_queue_limits",
931 	.attrs  = dql_attrs,
932 };
933 #endif /* CONFIG_BQL */
934 
935 #ifdef CONFIG_XPS
936 static inline unsigned int get_netdev_queue_index(struct netdev_queue *queue)
937 {
938 	struct net_device *dev = queue->dev;
939 	int i;
940 
941 	for (i = 0; i < dev->num_tx_queues; i++)
942 		if (queue == &dev->_tx[i])
943 			break;
944 
945 	BUG_ON(i >= dev->num_tx_queues);
946 
947 	return i;
948 }
949 
950 
951 static ssize_t show_xps_map(struct netdev_queue *queue,
952 			    struct netdev_queue_attribute *attribute, char *buf)
953 {
954 	struct net_device *dev = queue->dev;
955 	struct xps_dev_maps *dev_maps;
956 	cpumask_var_t mask;
957 	unsigned long index;
958 	size_t len = 0;
959 	int i;
960 
961 	if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
962 		return -ENOMEM;
963 
964 	index = get_netdev_queue_index(queue);
965 
966 	rcu_read_lock();
967 	dev_maps = rcu_dereference(dev->xps_maps);
968 	if (dev_maps) {
969 		for_each_possible_cpu(i) {
970 			struct xps_map *map =
971 			    rcu_dereference(dev_maps->cpu_map[i]);
972 			if (map) {
973 				int j;
974 				for (j = 0; j < map->len; j++) {
975 					if (map->queues[j] == index) {
976 						cpumask_set_cpu(i, mask);
977 						break;
978 					}
979 				}
980 			}
981 		}
982 	}
983 	rcu_read_unlock();
984 
985 	len += cpumask_scnprintf(buf + len, PAGE_SIZE, mask);
986 	if (PAGE_SIZE - len < 3) {
987 		free_cpumask_var(mask);
988 		return -EINVAL;
989 	}
990 
991 	free_cpumask_var(mask);
992 	len += sprintf(buf + len, "\n");
993 	return len;
994 }
995 
996 static ssize_t store_xps_map(struct netdev_queue *queue,
997 		      struct netdev_queue_attribute *attribute,
998 		      const char *buf, size_t len)
999 {
1000 	struct net_device *dev = queue->dev;
1001 	unsigned long index;
1002 	cpumask_var_t mask;
1003 	int err;
1004 
1005 	if (!capable(CAP_NET_ADMIN))
1006 		return -EPERM;
1007 
1008 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
1009 		return -ENOMEM;
1010 
1011 	index = get_netdev_queue_index(queue);
1012 
1013 	err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
1014 	if (err) {
1015 		free_cpumask_var(mask);
1016 		return err;
1017 	}
1018 
1019 	err = netif_set_xps_queue(dev, mask, index);
1020 
1021 	free_cpumask_var(mask);
1022 
1023 	return err ? : len;
1024 }
1025 
1026 static struct netdev_queue_attribute xps_cpus_attribute =
1027     __ATTR(xps_cpus, S_IRUGO | S_IWUSR, show_xps_map, store_xps_map);
1028 #endif /* CONFIG_XPS */
1029 
1030 static struct attribute *netdev_queue_default_attrs[] = {
1031 	&queue_trans_timeout.attr,
1032 #ifdef CONFIG_XPS
1033 	&xps_cpus_attribute.attr,
1034 #endif
1035 	NULL
1036 };
1037 
1038 static void netdev_queue_release(struct kobject *kobj)
1039 {
1040 	struct netdev_queue *queue = to_netdev_queue(kobj);
1041 
1042 	memset(kobj, 0, sizeof(*kobj));
1043 	dev_put(queue->dev);
1044 }
1045 
1046 static struct kobj_type netdev_queue_ktype = {
1047 	.sysfs_ops = &netdev_queue_sysfs_ops,
1048 	.release = netdev_queue_release,
1049 	.default_attrs = netdev_queue_default_attrs,
1050 };
1051 
1052 static int netdev_queue_add_kobject(struct net_device *net, int index)
1053 {
1054 	struct netdev_queue *queue = net->_tx + index;
1055 	struct kobject *kobj = &queue->kobj;
1056 	int error = 0;
1057 
1058 	kobj->kset = net->queues_kset;
1059 	error = kobject_init_and_add(kobj, &netdev_queue_ktype, NULL,
1060 	    "tx-%u", index);
1061 	if (error)
1062 		goto exit;
1063 
1064 #ifdef CONFIG_BQL
1065 	error = sysfs_create_group(kobj, &dql_group);
1066 	if (error)
1067 		goto exit;
1068 #endif
1069 
1070 	kobject_uevent(kobj, KOBJ_ADD);
1071 	dev_hold(queue->dev);
1072 
1073 	return 0;
1074 exit:
1075 	kobject_put(kobj);
1076 	return error;
1077 }
1078 #endif /* CONFIG_SYSFS */
1079 
1080 int
1081 netdev_queue_update_kobjects(struct net_device *net, int old_num, int new_num)
1082 {
1083 #ifdef CONFIG_SYSFS
1084 	int i;
1085 	int error = 0;
1086 
1087 	for (i = old_num; i < new_num; i++) {
1088 		error = netdev_queue_add_kobject(net, i);
1089 		if (error) {
1090 			new_num = old_num;
1091 			break;
1092 		}
1093 	}
1094 
1095 	while (--i >= new_num) {
1096 		struct netdev_queue *queue = net->_tx + i;
1097 
1098 #ifdef CONFIG_BQL
1099 		sysfs_remove_group(&queue->kobj, &dql_group);
1100 #endif
1101 		kobject_put(&queue->kobj);
1102 	}
1103 
1104 	return error;
1105 #else
1106 	return 0;
1107 #endif /* CONFIG_SYSFS */
1108 }
1109 
1110 static int register_queue_kobjects(struct net_device *net)
1111 {
1112 	int error = 0, txq = 0, rxq = 0, real_rx = 0, real_tx = 0;
1113 
1114 #ifdef CONFIG_SYSFS
1115 	net->queues_kset = kset_create_and_add("queues",
1116 	    NULL, &net->dev.kobj);
1117 	if (!net->queues_kset)
1118 		return -ENOMEM;
1119 #endif
1120 
1121 #ifdef CONFIG_RPS
1122 	real_rx = net->real_num_rx_queues;
1123 #endif
1124 	real_tx = net->real_num_tx_queues;
1125 
1126 	error = net_rx_queue_update_kobjects(net, 0, real_rx);
1127 	if (error)
1128 		goto error;
1129 	rxq = real_rx;
1130 
1131 	error = netdev_queue_update_kobjects(net, 0, real_tx);
1132 	if (error)
1133 		goto error;
1134 	txq = real_tx;
1135 
1136 	return 0;
1137 
1138 error:
1139 	netdev_queue_update_kobjects(net, txq, 0);
1140 	net_rx_queue_update_kobjects(net, rxq, 0);
1141 	return error;
1142 }
1143 
1144 static void remove_queue_kobjects(struct net_device *net)
1145 {
1146 	int real_rx = 0, real_tx = 0;
1147 
1148 #ifdef CONFIG_RPS
1149 	real_rx = net->real_num_rx_queues;
1150 #endif
1151 	real_tx = net->real_num_tx_queues;
1152 
1153 	net_rx_queue_update_kobjects(net, real_rx, 0);
1154 	netdev_queue_update_kobjects(net, real_tx, 0);
1155 #ifdef CONFIG_SYSFS
1156 	kset_unregister(net->queues_kset);
1157 #endif
1158 }
1159 
1160 static void *net_grab_current_ns(void)
1161 {
1162 	struct net *ns = current->nsproxy->net_ns;
1163 #ifdef CONFIG_NET_NS
1164 	if (ns)
1165 		atomic_inc(&ns->passive);
1166 #endif
1167 	return ns;
1168 }
1169 
1170 static const void *net_initial_ns(void)
1171 {
1172 	return &init_net;
1173 }
1174 
1175 static const void *net_netlink_ns(struct sock *sk)
1176 {
1177 	return sock_net(sk);
1178 }
1179 
1180 struct kobj_ns_type_operations net_ns_type_operations = {
1181 	.type = KOBJ_NS_TYPE_NET,
1182 	.grab_current_ns = net_grab_current_ns,
1183 	.netlink_ns = net_netlink_ns,
1184 	.initial_ns = net_initial_ns,
1185 	.drop_ns = net_drop_ns,
1186 };
1187 EXPORT_SYMBOL_GPL(net_ns_type_operations);
1188 
1189 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
1190 {
1191 	struct net_device *dev = to_net_dev(d);
1192 	int retval;
1193 
1194 	/* pass interface to uevent. */
1195 	retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
1196 	if (retval)
1197 		goto exit;
1198 
1199 	/* pass ifindex to uevent.
1200 	 * ifindex is useful as it won't change (interface name may change)
1201 	 * and is what RtNetlink uses natively. */
1202 	retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
1203 
1204 exit:
1205 	return retval;
1206 }
1207 
1208 /*
1209  *	netdev_release -- destroy and free a dead device.
1210  *	Called when last reference to device kobject is gone.
1211  */
1212 static void netdev_release(struct device *d)
1213 {
1214 	struct net_device *dev = to_net_dev(d);
1215 
1216 	BUG_ON(dev->reg_state != NETREG_RELEASED);
1217 
1218 	kfree(dev->ifalias);
1219 	kfree((char *)dev - dev->padded);
1220 }
1221 
1222 static const void *net_namespace(struct device *d)
1223 {
1224 	struct net_device *dev;
1225 	dev = container_of(d, struct net_device, dev);
1226 	return dev_net(dev);
1227 }
1228 
1229 static struct class net_class = {
1230 	.name = "net",
1231 	.dev_release = netdev_release,
1232 #ifdef CONFIG_SYSFS
1233 	.dev_attrs = net_class_attributes,
1234 #endif /* CONFIG_SYSFS */
1235 	.dev_uevent = netdev_uevent,
1236 	.ns_type = &net_ns_type_operations,
1237 	.namespace = net_namespace,
1238 };
1239 
1240 /* Delete sysfs entries but hold kobject reference until after all
1241  * netdev references are gone.
1242  */
1243 void netdev_unregister_kobject(struct net_device * net)
1244 {
1245 	struct device *dev = &(net->dev);
1246 
1247 	kobject_get(&dev->kobj);
1248 
1249 	remove_queue_kobjects(net);
1250 
1251 	pm_runtime_set_memalloc_noio(dev, false);
1252 
1253 	device_del(dev);
1254 }
1255 
1256 /* Create sysfs entries for network device. */
1257 int netdev_register_kobject(struct net_device *net)
1258 {
1259 	struct device *dev = &(net->dev);
1260 	const struct attribute_group **groups = net->sysfs_groups;
1261 	int error = 0;
1262 
1263 	device_initialize(dev);
1264 	dev->class = &net_class;
1265 	dev->platform_data = net;
1266 	dev->groups = groups;
1267 
1268 	dev_set_name(dev, "%s", net->name);
1269 
1270 #ifdef CONFIG_SYSFS
1271 	/* Allow for a device specific group */
1272 	if (*groups)
1273 		groups++;
1274 
1275 	*groups++ = &netstat_group;
1276 
1277 #if IS_ENABLED(CONFIG_WIRELESS_EXT) || IS_ENABLED(CONFIG_CFG80211)
1278 	if (net->ieee80211_ptr)
1279 		*groups++ = &wireless_group;
1280 #if IS_ENABLED(CONFIG_WIRELESS_EXT)
1281 	else if (net->wireless_handlers)
1282 		*groups++ = &wireless_group;
1283 #endif
1284 #endif
1285 #endif /* CONFIG_SYSFS */
1286 
1287 	error = device_add(dev);
1288 	if (error)
1289 		return error;
1290 
1291 	error = register_queue_kobjects(net);
1292 	if (error) {
1293 		device_del(dev);
1294 		return error;
1295 	}
1296 
1297 	pm_runtime_set_memalloc_noio(dev, true);
1298 
1299 	return error;
1300 }
1301 
1302 int netdev_class_create_file(struct class_attribute *class_attr)
1303 {
1304 	return class_create_file(&net_class, class_attr);
1305 }
1306 EXPORT_SYMBOL(netdev_class_create_file);
1307 
1308 void netdev_class_remove_file(struct class_attribute *class_attr)
1309 {
1310 	class_remove_file(&net_class, class_attr);
1311 }
1312 EXPORT_SYMBOL(netdev_class_remove_file);
1313 
1314 int netdev_kobject_init(void)
1315 {
1316 	kobj_ns_type_register(&net_ns_type_operations);
1317 	return class_register(&net_class);
1318 }
1319