1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net-sysfs.c - network device class and attributes
4  *
5  * Copyright (c) 2003 Stephen Hemminger <shemminger@osdl.org>
6  */
7 
8 #include <linux/capability.h>
9 #include <linux/kernel.h>
10 #include <linux/netdevice.h>
11 #include <linux/if_arp.h>
12 #include <linux/slab.h>
13 #include <linux/sched/signal.h>
14 #include <linux/sched/isolation.h>
15 #include <linux/nsproxy.h>
16 #include <net/sock.h>
17 #include <net/net_namespace.h>
18 #include <linux/rtnetlink.h>
19 #include <linux/vmalloc.h>
20 #include <linux/export.h>
21 #include <linux/jiffies.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/of.h>
24 #include <linux/of_net.h>
25 #include <linux/cpu.h>
26 
27 #include "dev.h"
28 #include "net-sysfs.h"
29 
30 #ifdef CONFIG_SYSFS
31 static const char fmt_hex[] = "%#x\n";
32 static const char fmt_dec[] = "%d\n";
33 static const char fmt_ulong[] = "%lu\n";
34 static const char fmt_u64[] = "%llu\n";
35 
36 /* Caller holds RTNL or dev_base_lock */
dev_isalive(const struct net_device * dev)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 */
netdev_show(const struct device * dev,struct device_attribute * attr,char * buf,ssize_t (* format)(const struct net_device *,char *))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 */
netdev_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len,int (* set)(struct net_device *,unsigned long))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;
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 		ret = (*set)(netdev, new);
100 		if (ret == 0)
101 			ret = len;
102 	}
103 	rtnl_unlock();
104  err:
105 	return ret;
106 }
107 
108 NETDEVICE_SHOW_RO(dev_id, fmt_hex);
109 NETDEVICE_SHOW_RO(dev_port, fmt_dec);
110 NETDEVICE_SHOW_RO(addr_assign_type, fmt_dec);
111 NETDEVICE_SHOW_RO(addr_len, 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 
iflink_show(struct device * dev,struct device_attribute * attr,char * buf)116 static ssize_t iflink_show(struct device *dev, struct device_attribute *attr,
117 			   char *buf)
118 {
119 	struct net_device *ndev = to_net_dev(dev);
120 
121 	return sprintf(buf, fmt_dec, dev_get_iflink(ndev));
122 }
123 static DEVICE_ATTR_RO(iflink);
124 
format_name_assign_type(const struct net_device * dev,char * buf)125 static ssize_t format_name_assign_type(const struct net_device *dev, char *buf)
126 {
127 	return sprintf(buf, fmt_dec, dev->name_assign_type);
128 }
129 
name_assign_type_show(struct device * dev,struct device_attribute * attr,char * buf)130 static ssize_t name_assign_type_show(struct device *dev,
131 				     struct device_attribute *attr,
132 				     char *buf)
133 {
134 	struct net_device *ndev = to_net_dev(dev);
135 	ssize_t ret = -EINVAL;
136 
137 	if (ndev->name_assign_type != NET_NAME_UNKNOWN)
138 		ret = netdev_show(dev, attr, buf, format_name_assign_type);
139 
140 	return ret;
141 }
142 static DEVICE_ATTR_RO(name_assign_type);
143 
144 /* use same locking rules as GIFHWADDR ioctl's */
address_show(struct device * dev,struct device_attribute * attr,char * buf)145 static ssize_t address_show(struct device *dev, struct device_attribute *attr,
146 			    char *buf)
147 {
148 	struct net_device *ndev = to_net_dev(dev);
149 	ssize_t ret = -EINVAL;
150 
151 	read_lock(&dev_base_lock);
152 	if (dev_isalive(ndev))
153 		ret = sysfs_format_mac(buf, ndev->dev_addr, ndev->addr_len);
154 	read_unlock(&dev_base_lock);
155 	return ret;
156 }
157 static DEVICE_ATTR_RO(address);
158 
broadcast_show(struct device * dev,struct device_attribute * attr,char * buf)159 static ssize_t broadcast_show(struct device *dev,
160 			      struct device_attribute *attr, char *buf)
161 {
162 	struct net_device *ndev = to_net_dev(dev);
163 
164 	if (dev_isalive(ndev))
165 		return sysfs_format_mac(buf, ndev->broadcast, ndev->addr_len);
166 	return -EINVAL;
167 }
168 static DEVICE_ATTR_RO(broadcast);
169 
change_carrier(struct net_device * dev,unsigned long new_carrier)170 static int change_carrier(struct net_device *dev, unsigned long new_carrier)
171 {
172 	if (!netif_running(dev))
173 		return -EINVAL;
174 	return dev_change_carrier(dev, (bool)new_carrier);
175 }
176 
carrier_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)177 static ssize_t carrier_store(struct device *dev, struct device_attribute *attr,
178 			     const char *buf, size_t len)
179 {
180 	struct net_device *netdev = to_net_dev(dev);
181 
182 	/* The check is also done in change_carrier; this helps returning early
183 	 * without hitting the trylock/restart in netdev_store.
184 	 */
185 	if (!netdev->netdev_ops->ndo_change_carrier)
186 		return -EOPNOTSUPP;
187 
188 	return netdev_store(dev, attr, buf, len, change_carrier);
189 }
190 
carrier_show(struct device * dev,struct device_attribute * attr,char * buf)191 static ssize_t carrier_show(struct device *dev,
192 			    struct device_attribute *attr, char *buf)
193 {
194 	struct net_device *netdev = to_net_dev(dev);
195 
196 	if (netif_running(netdev))
197 		return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
198 
199 	return -EINVAL;
200 }
201 static DEVICE_ATTR_RW(carrier);
202 
speed_show(struct device * dev,struct device_attribute * attr,char * buf)203 static ssize_t speed_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 	/* The check is also done in __ethtool_get_link_ksettings; this helps
210 	 * returning early without hitting the trylock/restart below.
211 	 */
212 	if (!netdev->ethtool_ops->get_link_ksettings)
213 		return ret;
214 
215 	if (!rtnl_trylock())
216 		return restart_syscall();
217 
218 	if (netif_running(netdev) && netif_device_present(netdev)) {
219 		struct ethtool_link_ksettings cmd;
220 
221 		if (!__ethtool_get_link_ksettings(netdev, &cmd))
222 			ret = sprintf(buf, fmt_dec, cmd.base.speed);
223 	}
224 	rtnl_unlock();
225 	return ret;
226 }
227 static DEVICE_ATTR_RO(speed);
228 
duplex_show(struct device * dev,struct device_attribute * attr,char * buf)229 static ssize_t duplex_show(struct device *dev,
230 			   struct device_attribute *attr, char *buf)
231 {
232 	struct net_device *netdev = to_net_dev(dev);
233 	int ret = -EINVAL;
234 
235 	/* The check is also done in __ethtool_get_link_ksettings; this helps
236 	 * returning early without hitting the trylock/restart below.
237 	 */
238 	if (!netdev->ethtool_ops->get_link_ksettings)
239 		return ret;
240 
241 	if (!rtnl_trylock())
242 		return restart_syscall();
243 
244 	if (netif_running(netdev)) {
245 		struct ethtool_link_ksettings cmd;
246 
247 		if (!__ethtool_get_link_ksettings(netdev, &cmd)) {
248 			const char *duplex;
249 
250 			switch (cmd.base.duplex) {
251 			case DUPLEX_HALF:
252 				duplex = "half";
253 				break;
254 			case DUPLEX_FULL:
255 				duplex = "full";
256 				break;
257 			default:
258 				duplex = "unknown";
259 				break;
260 			}
261 			ret = sprintf(buf, "%s\n", duplex);
262 		}
263 	}
264 	rtnl_unlock();
265 	return ret;
266 }
267 static DEVICE_ATTR_RO(duplex);
268 
testing_show(struct device * dev,struct device_attribute * attr,char * buf)269 static ssize_t testing_show(struct device *dev,
270 			    struct device_attribute *attr, char *buf)
271 {
272 	struct net_device *netdev = to_net_dev(dev);
273 
274 	if (netif_running(netdev))
275 		return sprintf(buf, fmt_dec, !!netif_testing(netdev));
276 
277 	return -EINVAL;
278 }
279 static DEVICE_ATTR_RO(testing);
280 
dormant_show(struct device * dev,struct device_attribute * attr,char * buf)281 static ssize_t dormant_show(struct device *dev,
282 			    struct device_attribute *attr, char *buf)
283 {
284 	struct net_device *netdev = to_net_dev(dev);
285 
286 	if (netif_running(netdev))
287 		return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
288 
289 	return -EINVAL;
290 }
291 static DEVICE_ATTR_RO(dormant);
292 
293 static const char *const operstates[] = {
294 	"unknown",
295 	"notpresent", /* currently unused */
296 	"down",
297 	"lowerlayerdown",
298 	"testing",
299 	"dormant",
300 	"up"
301 };
302 
operstate_show(struct device * dev,struct device_attribute * attr,char * buf)303 static ssize_t operstate_show(struct device *dev,
304 			      struct device_attribute *attr, char *buf)
305 {
306 	const struct net_device *netdev = to_net_dev(dev);
307 	unsigned char operstate;
308 
309 	read_lock(&dev_base_lock);
310 	operstate = netdev->operstate;
311 	if (!netif_running(netdev))
312 		operstate = IF_OPER_DOWN;
313 	read_unlock(&dev_base_lock);
314 
315 	if (operstate >= ARRAY_SIZE(operstates))
316 		return -EINVAL; /* should not happen */
317 
318 	return sprintf(buf, "%s\n", operstates[operstate]);
319 }
320 static DEVICE_ATTR_RO(operstate);
321 
carrier_changes_show(struct device * dev,struct device_attribute * attr,char * buf)322 static ssize_t carrier_changes_show(struct device *dev,
323 				    struct device_attribute *attr,
324 				    char *buf)
325 {
326 	struct net_device *netdev = to_net_dev(dev);
327 
328 	return sprintf(buf, fmt_dec,
329 		       atomic_read(&netdev->carrier_up_count) +
330 		       atomic_read(&netdev->carrier_down_count));
331 }
332 static DEVICE_ATTR_RO(carrier_changes);
333 
carrier_up_count_show(struct device * dev,struct device_attribute * attr,char * buf)334 static ssize_t carrier_up_count_show(struct device *dev,
335 				     struct device_attribute *attr,
336 				     char *buf)
337 {
338 	struct net_device *netdev = to_net_dev(dev);
339 
340 	return sprintf(buf, fmt_dec, atomic_read(&netdev->carrier_up_count));
341 }
342 static DEVICE_ATTR_RO(carrier_up_count);
343 
carrier_down_count_show(struct device * dev,struct device_attribute * attr,char * buf)344 static ssize_t carrier_down_count_show(struct device *dev,
345 				       struct device_attribute *attr,
346 				       char *buf)
347 {
348 	struct net_device *netdev = to_net_dev(dev);
349 
350 	return sprintf(buf, fmt_dec, atomic_read(&netdev->carrier_down_count));
351 }
352 static DEVICE_ATTR_RO(carrier_down_count);
353 
354 /* read-write attributes */
355 
change_mtu(struct net_device * dev,unsigned long new_mtu)356 static int change_mtu(struct net_device *dev, unsigned long new_mtu)
357 {
358 	return dev_set_mtu(dev, (int)new_mtu);
359 }
360 
mtu_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)361 static ssize_t mtu_store(struct device *dev, struct device_attribute *attr,
362 			 const char *buf, size_t len)
363 {
364 	return netdev_store(dev, attr, buf, len, change_mtu);
365 }
366 NETDEVICE_SHOW_RW(mtu, fmt_dec);
367 
change_flags(struct net_device * dev,unsigned long new_flags)368 static int change_flags(struct net_device *dev, unsigned long new_flags)
369 {
370 	return dev_change_flags(dev, (unsigned int)new_flags, NULL);
371 }
372 
flags_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)373 static ssize_t flags_store(struct device *dev, struct device_attribute *attr,
374 			   const char *buf, size_t len)
375 {
376 	return netdev_store(dev, attr, buf, len, change_flags);
377 }
378 NETDEVICE_SHOW_RW(flags, fmt_hex);
379 
tx_queue_len_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)380 static ssize_t tx_queue_len_store(struct device *dev,
381 				  struct device_attribute *attr,
382 				  const char *buf, size_t len)
383 {
384 	if (!capable(CAP_NET_ADMIN))
385 		return -EPERM;
386 
387 	return netdev_store(dev, attr, buf, len, dev_change_tx_queue_len);
388 }
389 NETDEVICE_SHOW_RW(tx_queue_len, fmt_dec);
390 
change_gro_flush_timeout(struct net_device * dev,unsigned long val)391 static int change_gro_flush_timeout(struct net_device *dev, unsigned long val)
392 {
393 	WRITE_ONCE(dev->gro_flush_timeout, val);
394 	return 0;
395 }
396 
gro_flush_timeout_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)397 static ssize_t gro_flush_timeout_store(struct device *dev,
398 				       struct device_attribute *attr,
399 				       const char *buf, size_t len)
400 {
401 	if (!capable(CAP_NET_ADMIN))
402 		return -EPERM;
403 
404 	return netdev_store(dev, attr, buf, len, change_gro_flush_timeout);
405 }
406 NETDEVICE_SHOW_RW(gro_flush_timeout, fmt_ulong);
407 
change_napi_defer_hard_irqs(struct net_device * dev,unsigned long val)408 static int change_napi_defer_hard_irqs(struct net_device *dev, unsigned long val)
409 {
410 	WRITE_ONCE(dev->napi_defer_hard_irqs, val);
411 	return 0;
412 }
413 
napi_defer_hard_irqs_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)414 static ssize_t napi_defer_hard_irqs_store(struct device *dev,
415 					  struct device_attribute *attr,
416 					  const char *buf, size_t len)
417 {
418 	if (!capable(CAP_NET_ADMIN))
419 		return -EPERM;
420 
421 	return netdev_store(dev, attr, buf, len, change_napi_defer_hard_irqs);
422 }
423 NETDEVICE_SHOW_RW(napi_defer_hard_irqs, fmt_dec);
424 
ifalias_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)425 static ssize_t ifalias_store(struct device *dev, struct device_attribute *attr,
426 			     const char *buf, size_t len)
427 {
428 	struct net_device *netdev = to_net_dev(dev);
429 	struct net *net = dev_net(netdev);
430 	size_t count = len;
431 	ssize_t ret = 0;
432 
433 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
434 		return -EPERM;
435 
436 	/* ignore trailing newline */
437 	if (len >  0 && buf[len - 1] == '\n')
438 		--count;
439 
440 	if (!rtnl_trylock())
441 		return restart_syscall();
442 
443 	if (dev_isalive(netdev)) {
444 		ret = dev_set_alias(netdev, buf, count);
445 		if (ret < 0)
446 			goto err;
447 		ret = len;
448 		netdev_state_change(netdev);
449 	}
450 err:
451 	rtnl_unlock();
452 
453 	return ret;
454 }
455 
ifalias_show(struct device * dev,struct device_attribute * attr,char * buf)456 static ssize_t ifalias_show(struct device *dev,
457 			    struct device_attribute *attr, char *buf)
458 {
459 	const struct net_device *netdev = to_net_dev(dev);
460 	char tmp[IFALIASZ];
461 	ssize_t ret = 0;
462 
463 	ret = dev_get_alias(netdev, tmp, sizeof(tmp));
464 	if (ret > 0)
465 		ret = sprintf(buf, "%s\n", tmp);
466 	return ret;
467 }
468 static DEVICE_ATTR_RW(ifalias);
469 
change_group(struct net_device * dev,unsigned long new_group)470 static int change_group(struct net_device *dev, unsigned long new_group)
471 {
472 	dev_set_group(dev, (int)new_group);
473 	return 0;
474 }
475 
group_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)476 static ssize_t group_store(struct device *dev, struct device_attribute *attr,
477 			   const char *buf, size_t len)
478 {
479 	return netdev_store(dev, attr, buf, len, change_group);
480 }
481 NETDEVICE_SHOW(group, fmt_dec);
482 static DEVICE_ATTR(netdev_group, 0644, group_show, group_store);
483 
change_proto_down(struct net_device * dev,unsigned long proto_down)484 static int change_proto_down(struct net_device *dev, unsigned long proto_down)
485 {
486 	return dev_change_proto_down(dev, (bool)proto_down);
487 }
488 
proto_down_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)489 static ssize_t proto_down_store(struct device *dev,
490 				struct device_attribute *attr,
491 				const char *buf, size_t len)
492 {
493 	return netdev_store(dev, attr, buf, len, change_proto_down);
494 }
495 NETDEVICE_SHOW_RW(proto_down, fmt_dec);
496 
phys_port_id_show(struct device * dev,struct device_attribute * attr,char * buf)497 static ssize_t phys_port_id_show(struct device *dev,
498 				 struct device_attribute *attr, char *buf)
499 {
500 	struct net_device *netdev = to_net_dev(dev);
501 	ssize_t ret = -EINVAL;
502 
503 	/* The check is also done in dev_get_phys_port_id; this helps returning
504 	 * early without hitting the trylock/restart below.
505 	 */
506 	if (!netdev->netdev_ops->ndo_get_phys_port_id)
507 		return -EOPNOTSUPP;
508 
509 	if (!rtnl_trylock())
510 		return restart_syscall();
511 
512 	if (dev_isalive(netdev)) {
513 		struct netdev_phys_item_id ppid;
514 
515 		ret = dev_get_phys_port_id(netdev, &ppid);
516 		if (!ret)
517 			ret = sprintf(buf, "%*phN\n", ppid.id_len, ppid.id);
518 	}
519 	rtnl_unlock();
520 
521 	return ret;
522 }
523 static DEVICE_ATTR_RO(phys_port_id);
524 
phys_port_name_show(struct device * dev,struct device_attribute * attr,char * buf)525 static ssize_t phys_port_name_show(struct device *dev,
526 				   struct device_attribute *attr, char *buf)
527 {
528 	struct net_device *netdev = to_net_dev(dev);
529 	ssize_t ret = -EINVAL;
530 
531 	/* The checks are also done in dev_get_phys_port_name; this helps
532 	 * returning early without hitting the trylock/restart below.
533 	 */
534 	if (!netdev->netdev_ops->ndo_get_phys_port_name &&
535 	    !netdev->netdev_ops->ndo_get_devlink_port)
536 		return -EOPNOTSUPP;
537 
538 	if (!rtnl_trylock())
539 		return restart_syscall();
540 
541 	if (dev_isalive(netdev)) {
542 		char name[IFNAMSIZ];
543 
544 		ret = dev_get_phys_port_name(netdev, name, sizeof(name));
545 		if (!ret)
546 			ret = sprintf(buf, "%s\n", name);
547 	}
548 	rtnl_unlock();
549 
550 	return ret;
551 }
552 static DEVICE_ATTR_RO(phys_port_name);
553 
phys_switch_id_show(struct device * dev,struct device_attribute * attr,char * buf)554 static ssize_t phys_switch_id_show(struct device *dev,
555 				   struct device_attribute *attr, char *buf)
556 {
557 	struct net_device *netdev = to_net_dev(dev);
558 	ssize_t ret = -EINVAL;
559 
560 	/* The checks are also done in dev_get_phys_port_name; this helps
561 	 * returning early without hitting the trylock/restart below. This works
562 	 * because recurse is false when calling dev_get_port_parent_id.
563 	 */
564 	if (!netdev->netdev_ops->ndo_get_port_parent_id &&
565 	    !netdev->netdev_ops->ndo_get_devlink_port)
566 		return -EOPNOTSUPP;
567 
568 	if (!rtnl_trylock())
569 		return restart_syscall();
570 
571 	if (dev_isalive(netdev)) {
572 		struct netdev_phys_item_id ppid = { };
573 
574 		ret = dev_get_port_parent_id(netdev, &ppid, false);
575 		if (!ret)
576 			ret = sprintf(buf, "%*phN\n", ppid.id_len, ppid.id);
577 	}
578 	rtnl_unlock();
579 
580 	return ret;
581 }
582 static DEVICE_ATTR_RO(phys_switch_id);
583 
threaded_show(struct device * dev,struct device_attribute * attr,char * buf)584 static ssize_t threaded_show(struct device *dev,
585 			     struct device_attribute *attr, char *buf)
586 {
587 	struct net_device *netdev = to_net_dev(dev);
588 	ssize_t ret = -EINVAL;
589 
590 	if (!rtnl_trylock())
591 		return restart_syscall();
592 
593 	if (dev_isalive(netdev))
594 		ret = sprintf(buf, fmt_dec, netdev->threaded);
595 
596 	rtnl_unlock();
597 	return ret;
598 }
599 
modify_napi_threaded(struct net_device * dev,unsigned long val)600 static int modify_napi_threaded(struct net_device *dev, unsigned long val)
601 {
602 	int ret;
603 
604 	if (list_empty(&dev->napi_list))
605 		return -EOPNOTSUPP;
606 
607 	if (val != 0 && val != 1)
608 		return -EOPNOTSUPP;
609 
610 	ret = dev_set_threaded(dev, val);
611 
612 	return ret;
613 }
614 
threaded_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)615 static ssize_t threaded_store(struct device *dev,
616 			      struct device_attribute *attr,
617 			      const char *buf, size_t len)
618 {
619 	return netdev_store(dev, attr, buf, len, modify_napi_threaded);
620 }
621 static DEVICE_ATTR_RW(threaded);
622 
623 static struct attribute *net_class_attrs[] __ro_after_init = {
624 	&dev_attr_netdev_group.attr,
625 	&dev_attr_type.attr,
626 	&dev_attr_dev_id.attr,
627 	&dev_attr_dev_port.attr,
628 	&dev_attr_iflink.attr,
629 	&dev_attr_ifindex.attr,
630 	&dev_attr_name_assign_type.attr,
631 	&dev_attr_addr_assign_type.attr,
632 	&dev_attr_addr_len.attr,
633 	&dev_attr_link_mode.attr,
634 	&dev_attr_address.attr,
635 	&dev_attr_broadcast.attr,
636 	&dev_attr_speed.attr,
637 	&dev_attr_duplex.attr,
638 	&dev_attr_dormant.attr,
639 	&dev_attr_testing.attr,
640 	&dev_attr_operstate.attr,
641 	&dev_attr_carrier_changes.attr,
642 	&dev_attr_ifalias.attr,
643 	&dev_attr_carrier.attr,
644 	&dev_attr_mtu.attr,
645 	&dev_attr_flags.attr,
646 	&dev_attr_tx_queue_len.attr,
647 	&dev_attr_gro_flush_timeout.attr,
648 	&dev_attr_napi_defer_hard_irqs.attr,
649 	&dev_attr_phys_port_id.attr,
650 	&dev_attr_phys_port_name.attr,
651 	&dev_attr_phys_switch_id.attr,
652 	&dev_attr_proto_down.attr,
653 	&dev_attr_carrier_up_count.attr,
654 	&dev_attr_carrier_down_count.attr,
655 	&dev_attr_threaded.attr,
656 	NULL,
657 };
658 ATTRIBUTE_GROUPS(net_class);
659 
660 /* Show a given an attribute in the statistics group */
netstat_show(const struct device * d,struct device_attribute * attr,char * buf,unsigned long offset)661 static ssize_t netstat_show(const struct device *d,
662 			    struct device_attribute *attr, char *buf,
663 			    unsigned long offset)
664 {
665 	struct net_device *dev = to_net_dev(d);
666 	ssize_t ret = -EINVAL;
667 
668 	WARN_ON(offset > sizeof(struct rtnl_link_stats64) ||
669 		offset % sizeof(u64) != 0);
670 
671 	read_lock(&dev_base_lock);
672 	if (dev_isalive(dev)) {
673 		struct rtnl_link_stats64 temp;
674 		const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
675 
676 		ret = sprintf(buf, fmt_u64, *(u64 *)(((u8 *)stats) + offset));
677 	}
678 	read_unlock(&dev_base_lock);
679 	return ret;
680 }
681 
682 /* generate a read-only statistics attribute */
683 #define NETSTAT_ENTRY(name)						\
684 static ssize_t name##_show(struct device *d,				\
685 			   struct device_attribute *attr, char *buf)	\
686 {									\
687 	return netstat_show(d, attr, buf,				\
688 			    offsetof(struct rtnl_link_stats64, name));	\
689 }									\
690 static DEVICE_ATTR_RO(name)
691 
692 NETSTAT_ENTRY(rx_packets);
693 NETSTAT_ENTRY(tx_packets);
694 NETSTAT_ENTRY(rx_bytes);
695 NETSTAT_ENTRY(tx_bytes);
696 NETSTAT_ENTRY(rx_errors);
697 NETSTAT_ENTRY(tx_errors);
698 NETSTAT_ENTRY(rx_dropped);
699 NETSTAT_ENTRY(tx_dropped);
700 NETSTAT_ENTRY(multicast);
701 NETSTAT_ENTRY(collisions);
702 NETSTAT_ENTRY(rx_length_errors);
703 NETSTAT_ENTRY(rx_over_errors);
704 NETSTAT_ENTRY(rx_crc_errors);
705 NETSTAT_ENTRY(rx_frame_errors);
706 NETSTAT_ENTRY(rx_fifo_errors);
707 NETSTAT_ENTRY(rx_missed_errors);
708 NETSTAT_ENTRY(tx_aborted_errors);
709 NETSTAT_ENTRY(tx_carrier_errors);
710 NETSTAT_ENTRY(tx_fifo_errors);
711 NETSTAT_ENTRY(tx_heartbeat_errors);
712 NETSTAT_ENTRY(tx_window_errors);
713 NETSTAT_ENTRY(rx_compressed);
714 NETSTAT_ENTRY(tx_compressed);
715 NETSTAT_ENTRY(rx_nohandler);
716 
717 static struct attribute *netstat_attrs[] __ro_after_init = {
718 	&dev_attr_rx_packets.attr,
719 	&dev_attr_tx_packets.attr,
720 	&dev_attr_rx_bytes.attr,
721 	&dev_attr_tx_bytes.attr,
722 	&dev_attr_rx_errors.attr,
723 	&dev_attr_tx_errors.attr,
724 	&dev_attr_rx_dropped.attr,
725 	&dev_attr_tx_dropped.attr,
726 	&dev_attr_multicast.attr,
727 	&dev_attr_collisions.attr,
728 	&dev_attr_rx_length_errors.attr,
729 	&dev_attr_rx_over_errors.attr,
730 	&dev_attr_rx_crc_errors.attr,
731 	&dev_attr_rx_frame_errors.attr,
732 	&dev_attr_rx_fifo_errors.attr,
733 	&dev_attr_rx_missed_errors.attr,
734 	&dev_attr_tx_aborted_errors.attr,
735 	&dev_attr_tx_carrier_errors.attr,
736 	&dev_attr_tx_fifo_errors.attr,
737 	&dev_attr_tx_heartbeat_errors.attr,
738 	&dev_attr_tx_window_errors.attr,
739 	&dev_attr_rx_compressed.attr,
740 	&dev_attr_tx_compressed.attr,
741 	&dev_attr_rx_nohandler.attr,
742 	NULL
743 };
744 
745 static const struct attribute_group netstat_group = {
746 	.name  = "statistics",
747 	.attrs  = netstat_attrs,
748 };
749 
750 static struct attribute *wireless_attrs[] = {
751 	NULL
752 };
753 
754 static const struct attribute_group wireless_group = {
755 	.name = "wireless",
756 	.attrs = wireless_attrs,
757 };
758 
wireless_group_needed(struct net_device * ndev)759 static bool wireless_group_needed(struct net_device *ndev)
760 {
761 #if IS_ENABLED(CONFIG_CFG80211)
762 	if (ndev->ieee80211_ptr)
763 		return true;
764 #endif
765 #if IS_ENABLED(CONFIG_WIRELESS_EXT)
766 	if (ndev->wireless_handlers)
767 		return true;
768 #endif
769 	return false;
770 }
771 
772 #else /* CONFIG_SYSFS */
773 #define net_class_groups	NULL
774 #endif /* CONFIG_SYSFS */
775 
776 #ifdef CONFIG_SYSFS
777 #define to_rx_queue_attr(_attr) \
778 	container_of(_attr, struct rx_queue_attribute, attr)
779 
780 #define to_rx_queue(obj) container_of(obj, struct netdev_rx_queue, kobj)
781 
rx_queue_attr_show(struct kobject * kobj,struct attribute * attr,char * buf)782 static ssize_t rx_queue_attr_show(struct kobject *kobj, struct attribute *attr,
783 				  char *buf)
784 {
785 	const struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
786 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
787 
788 	if (!attribute->show)
789 		return -EIO;
790 
791 	return attribute->show(queue, buf);
792 }
793 
rx_queue_attr_store(struct kobject * kobj,struct attribute * attr,const char * buf,size_t count)794 static ssize_t rx_queue_attr_store(struct kobject *kobj, struct attribute *attr,
795 				   const char *buf, size_t count)
796 {
797 	const struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
798 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
799 
800 	if (!attribute->store)
801 		return -EIO;
802 
803 	return attribute->store(queue, buf, count);
804 }
805 
806 static const struct sysfs_ops rx_queue_sysfs_ops = {
807 	.show = rx_queue_attr_show,
808 	.store = rx_queue_attr_store,
809 };
810 
811 #ifdef CONFIG_RPS
show_rps_map(struct netdev_rx_queue * queue,char * buf)812 static ssize_t show_rps_map(struct netdev_rx_queue *queue, char *buf)
813 {
814 	struct rps_map *map;
815 	cpumask_var_t mask;
816 	int i, len;
817 
818 	if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
819 		return -ENOMEM;
820 
821 	rcu_read_lock();
822 	map = rcu_dereference(queue->rps_map);
823 	if (map)
824 		for (i = 0; i < map->len; i++)
825 			cpumask_set_cpu(map->cpus[i], mask);
826 
827 	len = snprintf(buf, PAGE_SIZE, "%*pb\n", cpumask_pr_args(mask));
828 	rcu_read_unlock();
829 	free_cpumask_var(mask);
830 
831 	return len < PAGE_SIZE ? len : -EINVAL;
832 }
833 
store_rps_map(struct netdev_rx_queue * queue,const char * buf,size_t len)834 static ssize_t store_rps_map(struct netdev_rx_queue *queue,
835 			     const char *buf, size_t len)
836 {
837 	struct rps_map *old_map, *map;
838 	cpumask_var_t mask;
839 	int err, cpu, i;
840 	static DEFINE_MUTEX(rps_map_mutex);
841 
842 	if (!capable(CAP_NET_ADMIN))
843 		return -EPERM;
844 
845 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
846 		return -ENOMEM;
847 
848 	err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
849 	if (err) {
850 		free_cpumask_var(mask);
851 		return err;
852 	}
853 
854 	if (!cpumask_empty(mask)) {
855 		cpumask_and(mask, mask, housekeeping_cpumask(HK_TYPE_DOMAIN));
856 		cpumask_and(mask, mask, housekeeping_cpumask(HK_TYPE_WQ));
857 		if (cpumask_empty(mask)) {
858 			free_cpumask_var(mask);
859 			return -EINVAL;
860 		}
861 	}
862 
863 	map = kzalloc(max_t(unsigned int,
864 			    RPS_MAP_SIZE(cpumask_weight(mask)), L1_CACHE_BYTES),
865 		      GFP_KERNEL);
866 	if (!map) {
867 		free_cpumask_var(mask);
868 		return -ENOMEM;
869 	}
870 
871 	i = 0;
872 	for_each_cpu_and(cpu, mask, cpu_online_mask)
873 		map->cpus[i++] = cpu;
874 
875 	if (i) {
876 		map->len = i;
877 	} else {
878 		kfree(map);
879 		map = NULL;
880 	}
881 
882 	mutex_lock(&rps_map_mutex);
883 	old_map = rcu_dereference_protected(queue->rps_map,
884 					    mutex_is_locked(&rps_map_mutex));
885 	rcu_assign_pointer(queue->rps_map, map);
886 
887 	if (map)
888 		static_branch_inc(&rps_needed);
889 	if (old_map)
890 		static_branch_dec(&rps_needed);
891 
892 	mutex_unlock(&rps_map_mutex);
893 
894 	if (old_map)
895 		kfree_rcu(old_map, rcu);
896 
897 	free_cpumask_var(mask);
898 	return len;
899 }
900 
show_rps_dev_flow_table_cnt(struct netdev_rx_queue * queue,char * buf)901 static ssize_t show_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
902 					   char *buf)
903 {
904 	struct rps_dev_flow_table *flow_table;
905 	unsigned long val = 0;
906 
907 	rcu_read_lock();
908 	flow_table = rcu_dereference(queue->rps_flow_table);
909 	if (flow_table)
910 		val = (unsigned long)flow_table->mask + 1;
911 	rcu_read_unlock();
912 
913 	return sprintf(buf, "%lu\n", val);
914 }
915 
rps_dev_flow_table_release(struct rcu_head * rcu)916 static void rps_dev_flow_table_release(struct rcu_head *rcu)
917 {
918 	struct rps_dev_flow_table *table = container_of(rcu,
919 	    struct rps_dev_flow_table, rcu);
920 	vfree(table);
921 }
922 
store_rps_dev_flow_table_cnt(struct netdev_rx_queue * queue,const char * buf,size_t len)923 static ssize_t store_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
924 					    const char *buf, size_t len)
925 {
926 	unsigned long mask, count;
927 	struct rps_dev_flow_table *table, *old_table;
928 	static DEFINE_SPINLOCK(rps_dev_flow_lock);
929 	int rc;
930 
931 	if (!capable(CAP_NET_ADMIN))
932 		return -EPERM;
933 
934 	rc = kstrtoul(buf, 0, &count);
935 	if (rc < 0)
936 		return rc;
937 
938 	if (count) {
939 		mask = count - 1;
940 		/* mask = roundup_pow_of_two(count) - 1;
941 		 * without overflows...
942 		 */
943 		while ((mask | (mask >> 1)) != mask)
944 			mask |= (mask >> 1);
945 		/* On 64 bit arches, must check mask fits in table->mask (u32),
946 		 * and on 32bit arches, must check
947 		 * RPS_DEV_FLOW_TABLE_SIZE(mask + 1) doesn't overflow.
948 		 */
949 #if BITS_PER_LONG > 32
950 		if (mask > (unsigned long)(u32)mask)
951 			return -EINVAL;
952 #else
953 		if (mask > (ULONG_MAX - RPS_DEV_FLOW_TABLE_SIZE(1))
954 				/ sizeof(struct rps_dev_flow)) {
955 			/* Enforce a limit to prevent overflow */
956 			return -EINVAL;
957 		}
958 #endif
959 		table = vmalloc(RPS_DEV_FLOW_TABLE_SIZE(mask + 1));
960 		if (!table)
961 			return -ENOMEM;
962 
963 		table->mask = mask;
964 		for (count = 0; count <= mask; count++)
965 			table->flows[count].cpu = RPS_NO_CPU;
966 	} else {
967 		table = NULL;
968 	}
969 
970 	spin_lock(&rps_dev_flow_lock);
971 	old_table = rcu_dereference_protected(queue->rps_flow_table,
972 					      lockdep_is_held(&rps_dev_flow_lock));
973 	rcu_assign_pointer(queue->rps_flow_table, table);
974 	spin_unlock(&rps_dev_flow_lock);
975 
976 	if (old_table)
977 		call_rcu(&old_table->rcu, rps_dev_flow_table_release);
978 
979 	return len;
980 }
981 
982 static struct rx_queue_attribute rps_cpus_attribute __ro_after_init
983 	= __ATTR(rps_cpus, 0644, show_rps_map, store_rps_map);
984 
985 static struct rx_queue_attribute rps_dev_flow_table_cnt_attribute __ro_after_init
986 	= __ATTR(rps_flow_cnt, 0644,
987 		 show_rps_dev_flow_table_cnt, store_rps_dev_flow_table_cnt);
988 #endif /* CONFIG_RPS */
989 
990 static struct attribute *rx_queue_default_attrs[] __ro_after_init = {
991 #ifdef CONFIG_RPS
992 	&rps_cpus_attribute.attr,
993 	&rps_dev_flow_table_cnt_attribute.attr,
994 #endif
995 	NULL
996 };
997 ATTRIBUTE_GROUPS(rx_queue_default);
998 
rx_queue_release(struct kobject * kobj)999 static void rx_queue_release(struct kobject *kobj)
1000 {
1001 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
1002 #ifdef CONFIG_RPS
1003 	struct rps_map *map;
1004 	struct rps_dev_flow_table *flow_table;
1005 
1006 	map = rcu_dereference_protected(queue->rps_map, 1);
1007 	if (map) {
1008 		RCU_INIT_POINTER(queue->rps_map, NULL);
1009 		kfree_rcu(map, rcu);
1010 	}
1011 
1012 	flow_table = rcu_dereference_protected(queue->rps_flow_table, 1);
1013 	if (flow_table) {
1014 		RCU_INIT_POINTER(queue->rps_flow_table, NULL);
1015 		call_rcu(&flow_table->rcu, rps_dev_flow_table_release);
1016 	}
1017 #endif
1018 
1019 	memset(kobj, 0, sizeof(*kobj));
1020 	dev_put_track(queue->dev, &queue->dev_tracker);
1021 }
1022 
rx_queue_namespace(struct kobject * kobj)1023 static const void *rx_queue_namespace(struct kobject *kobj)
1024 {
1025 	struct netdev_rx_queue *queue = to_rx_queue(kobj);
1026 	struct device *dev = &queue->dev->dev;
1027 	const void *ns = NULL;
1028 
1029 	if (dev->class && dev->class->ns_type)
1030 		ns = dev->class->namespace(dev);
1031 
1032 	return ns;
1033 }
1034 
rx_queue_get_ownership(struct kobject * kobj,kuid_t * uid,kgid_t * gid)1035 static void rx_queue_get_ownership(struct kobject *kobj,
1036 				   kuid_t *uid, kgid_t *gid)
1037 {
1038 	const struct net *net = rx_queue_namespace(kobj);
1039 
1040 	net_ns_get_ownership(net, uid, gid);
1041 }
1042 
1043 static struct kobj_type rx_queue_ktype __ro_after_init = {
1044 	.sysfs_ops = &rx_queue_sysfs_ops,
1045 	.release = rx_queue_release,
1046 	.default_groups = rx_queue_default_groups,
1047 	.namespace = rx_queue_namespace,
1048 	.get_ownership = rx_queue_get_ownership,
1049 };
1050 
rx_queue_add_kobject(struct net_device * dev,int index)1051 static int rx_queue_add_kobject(struct net_device *dev, int index)
1052 {
1053 	struct netdev_rx_queue *queue = dev->_rx + index;
1054 	struct kobject *kobj = &queue->kobj;
1055 	int error = 0;
1056 
1057 	/* Kobject_put later will trigger rx_queue_release call which
1058 	 * decreases dev refcount: Take that reference here
1059 	 */
1060 	dev_hold_track(queue->dev, &queue->dev_tracker, GFP_KERNEL);
1061 
1062 	kobj->kset = dev->queues_kset;
1063 	error = kobject_init_and_add(kobj, &rx_queue_ktype, NULL,
1064 				     "rx-%u", index);
1065 	if (error)
1066 		goto err;
1067 
1068 	if (dev->sysfs_rx_queue_group) {
1069 		error = sysfs_create_group(kobj, dev->sysfs_rx_queue_group);
1070 		if (error)
1071 			goto err;
1072 	}
1073 
1074 	kobject_uevent(kobj, KOBJ_ADD);
1075 
1076 	return error;
1077 
1078 err:
1079 	kobject_put(kobj);
1080 	return error;
1081 }
1082 
rx_queue_change_owner(struct net_device * dev,int index,kuid_t kuid,kgid_t kgid)1083 static int rx_queue_change_owner(struct net_device *dev, int index, kuid_t kuid,
1084 				 kgid_t kgid)
1085 {
1086 	struct netdev_rx_queue *queue = dev->_rx + index;
1087 	struct kobject *kobj = &queue->kobj;
1088 	int error;
1089 
1090 	error = sysfs_change_owner(kobj, kuid, kgid);
1091 	if (error)
1092 		return error;
1093 
1094 	if (dev->sysfs_rx_queue_group)
1095 		error = sysfs_group_change_owner(
1096 			kobj, dev->sysfs_rx_queue_group, kuid, kgid);
1097 
1098 	return error;
1099 }
1100 #endif /* CONFIG_SYSFS */
1101 
1102 int
net_rx_queue_update_kobjects(struct net_device * dev,int old_num,int new_num)1103 net_rx_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
1104 {
1105 #ifdef CONFIG_SYSFS
1106 	int i;
1107 	int error = 0;
1108 
1109 #ifndef CONFIG_RPS
1110 	if (!dev->sysfs_rx_queue_group)
1111 		return 0;
1112 #endif
1113 	for (i = old_num; i < new_num; i++) {
1114 		error = rx_queue_add_kobject(dev, i);
1115 		if (error) {
1116 			new_num = old_num;
1117 			break;
1118 		}
1119 	}
1120 
1121 	while (--i >= new_num) {
1122 		struct kobject *kobj = &dev->_rx[i].kobj;
1123 
1124 		if (!refcount_read(&dev_net(dev)->ns.count))
1125 			kobj->uevent_suppress = 1;
1126 		if (dev->sysfs_rx_queue_group)
1127 			sysfs_remove_group(kobj, dev->sysfs_rx_queue_group);
1128 		kobject_put(kobj);
1129 	}
1130 
1131 	return error;
1132 #else
1133 	return 0;
1134 #endif
1135 }
1136 
net_rx_queue_change_owner(struct net_device * dev,int num,kuid_t kuid,kgid_t kgid)1137 static int net_rx_queue_change_owner(struct net_device *dev, int num,
1138 				     kuid_t kuid, kgid_t kgid)
1139 {
1140 #ifdef CONFIG_SYSFS
1141 	int error = 0;
1142 	int i;
1143 
1144 #ifndef CONFIG_RPS
1145 	if (!dev->sysfs_rx_queue_group)
1146 		return 0;
1147 #endif
1148 	for (i = 0; i < num; i++) {
1149 		error = rx_queue_change_owner(dev, i, kuid, kgid);
1150 		if (error)
1151 			break;
1152 	}
1153 
1154 	return error;
1155 #else
1156 	return 0;
1157 #endif
1158 }
1159 
1160 #ifdef CONFIG_SYSFS
1161 /*
1162  * netdev_queue sysfs structures and functions.
1163  */
1164 struct netdev_queue_attribute {
1165 	struct attribute attr;
1166 	ssize_t (*show)(struct netdev_queue *queue, char *buf);
1167 	ssize_t (*store)(struct netdev_queue *queue,
1168 			 const char *buf, size_t len);
1169 };
1170 #define to_netdev_queue_attr(_attr) \
1171 	container_of(_attr, struct netdev_queue_attribute, attr)
1172 
1173 #define to_netdev_queue(obj) container_of(obj, struct netdev_queue, kobj)
1174 
netdev_queue_attr_show(struct kobject * kobj,struct attribute * attr,char * buf)1175 static ssize_t netdev_queue_attr_show(struct kobject *kobj,
1176 				      struct attribute *attr, char *buf)
1177 {
1178 	const struct netdev_queue_attribute *attribute
1179 		= to_netdev_queue_attr(attr);
1180 	struct netdev_queue *queue = to_netdev_queue(kobj);
1181 
1182 	if (!attribute->show)
1183 		return -EIO;
1184 
1185 	return attribute->show(queue, buf);
1186 }
1187 
netdev_queue_attr_store(struct kobject * kobj,struct attribute * attr,const char * buf,size_t count)1188 static ssize_t netdev_queue_attr_store(struct kobject *kobj,
1189 				       struct attribute *attr,
1190 				       const char *buf, size_t count)
1191 {
1192 	const struct netdev_queue_attribute *attribute
1193 		= to_netdev_queue_attr(attr);
1194 	struct netdev_queue *queue = to_netdev_queue(kobj);
1195 
1196 	if (!attribute->store)
1197 		return -EIO;
1198 
1199 	return attribute->store(queue, buf, count);
1200 }
1201 
1202 static const struct sysfs_ops netdev_queue_sysfs_ops = {
1203 	.show = netdev_queue_attr_show,
1204 	.store = netdev_queue_attr_store,
1205 };
1206 
tx_timeout_show(struct netdev_queue * queue,char * buf)1207 static ssize_t tx_timeout_show(struct netdev_queue *queue, char *buf)
1208 {
1209 	unsigned long trans_timeout = atomic_long_read(&queue->trans_timeout);
1210 
1211 	return sprintf(buf, fmt_ulong, trans_timeout);
1212 }
1213 
get_netdev_queue_index(struct netdev_queue * queue)1214 static unsigned int get_netdev_queue_index(struct netdev_queue *queue)
1215 {
1216 	struct net_device *dev = queue->dev;
1217 	unsigned int i;
1218 
1219 	i = queue - dev->_tx;
1220 	BUG_ON(i >= dev->num_tx_queues);
1221 
1222 	return i;
1223 }
1224 
traffic_class_show(struct netdev_queue * queue,char * buf)1225 static ssize_t traffic_class_show(struct netdev_queue *queue,
1226 				  char *buf)
1227 {
1228 	struct net_device *dev = queue->dev;
1229 	int num_tc, tc;
1230 	int index;
1231 
1232 	if (!netif_is_multiqueue(dev))
1233 		return -ENOENT;
1234 
1235 	if (!rtnl_trylock())
1236 		return restart_syscall();
1237 
1238 	index = get_netdev_queue_index(queue);
1239 
1240 	/* If queue belongs to subordinate dev use its TC mapping */
1241 	dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev;
1242 
1243 	num_tc = dev->num_tc;
1244 	tc = netdev_txq_to_tc(dev, index);
1245 
1246 	rtnl_unlock();
1247 
1248 	if (tc < 0)
1249 		return -EINVAL;
1250 
1251 	/* We can report the traffic class one of two ways:
1252 	 * Subordinate device traffic classes are reported with the traffic
1253 	 * class first, and then the subordinate class so for example TC0 on
1254 	 * subordinate device 2 will be reported as "0-2". If the queue
1255 	 * belongs to the root device it will be reported with just the
1256 	 * traffic class, so just "0" for TC 0 for example.
1257 	 */
1258 	return num_tc < 0 ? sprintf(buf, "%d%d\n", tc, num_tc) :
1259 			    sprintf(buf, "%d\n", tc);
1260 }
1261 
1262 #ifdef CONFIG_XPS
tx_maxrate_show(struct netdev_queue * queue,char * buf)1263 static ssize_t tx_maxrate_show(struct netdev_queue *queue,
1264 			       char *buf)
1265 {
1266 	return sprintf(buf, "%lu\n", queue->tx_maxrate);
1267 }
1268 
tx_maxrate_store(struct netdev_queue * queue,const char * buf,size_t len)1269 static ssize_t tx_maxrate_store(struct netdev_queue *queue,
1270 				const char *buf, size_t len)
1271 {
1272 	struct net_device *dev = queue->dev;
1273 	int err, index = get_netdev_queue_index(queue);
1274 	u32 rate = 0;
1275 
1276 	if (!capable(CAP_NET_ADMIN))
1277 		return -EPERM;
1278 
1279 	/* The check is also done later; this helps returning early without
1280 	 * hitting the trylock/restart below.
1281 	 */
1282 	if (!dev->netdev_ops->ndo_set_tx_maxrate)
1283 		return -EOPNOTSUPP;
1284 
1285 	err = kstrtou32(buf, 10, &rate);
1286 	if (err < 0)
1287 		return err;
1288 
1289 	if (!rtnl_trylock())
1290 		return restart_syscall();
1291 
1292 	err = -EOPNOTSUPP;
1293 	if (dev->netdev_ops->ndo_set_tx_maxrate)
1294 		err = dev->netdev_ops->ndo_set_tx_maxrate(dev, index, rate);
1295 
1296 	rtnl_unlock();
1297 	if (!err) {
1298 		queue->tx_maxrate = rate;
1299 		return len;
1300 	}
1301 	return err;
1302 }
1303 
1304 static struct netdev_queue_attribute queue_tx_maxrate __ro_after_init
1305 	= __ATTR_RW(tx_maxrate);
1306 #endif
1307 
1308 static struct netdev_queue_attribute queue_trans_timeout __ro_after_init
1309 	= __ATTR_RO(tx_timeout);
1310 
1311 static struct netdev_queue_attribute queue_traffic_class __ro_after_init
1312 	= __ATTR_RO(traffic_class);
1313 
1314 #ifdef CONFIG_BQL
1315 /*
1316  * Byte queue limits sysfs structures and functions.
1317  */
bql_show(char * buf,unsigned int value)1318 static ssize_t bql_show(char *buf, unsigned int value)
1319 {
1320 	return sprintf(buf, "%u\n", value);
1321 }
1322 
bql_set(const char * buf,const size_t count,unsigned int * pvalue)1323 static ssize_t bql_set(const char *buf, const size_t count,
1324 		       unsigned int *pvalue)
1325 {
1326 	unsigned int value;
1327 	int err;
1328 
1329 	if (!strcmp(buf, "max") || !strcmp(buf, "max\n")) {
1330 		value = DQL_MAX_LIMIT;
1331 	} else {
1332 		err = kstrtouint(buf, 10, &value);
1333 		if (err < 0)
1334 			return err;
1335 		if (value > DQL_MAX_LIMIT)
1336 			return -EINVAL;
1337 	}
1338 
1339 	*pvalue = value;
1340 
1341 	return count;
1342 }
1343 
bql_show_hold_time(struct netdev_queue * queue,char * buf)1344 static ssize_t bql_show_hold_time(struct netdev_queue *queue,
1345 				  char *buf)
1346 {
1347 	struct dql *dql = &queue->dql;
1348 
1349 	return sprintf(buf, "%u\n", jiffies_to_msecs(dql->slack_hold_time));
1350 }
1351 
bql_set_hold_time(struct netdev_queue * queue,const char * buf,size_t len)1352 static ssize_t bql_set_hold_time(struct netdev_queue *queue,
1353 				 const char *buf, size_t len)
1354 {
1355 	struct dql *dql = &queue->dql;
1356 	unsigned int value;
1357 	int err;
1358 
1359 	err = kstrtouint(buf, 10, &value);
1360 	if (err < 0)
1361 		return err;
1362 
1363 	dql->slack_hold_time = msecs_to_jiffies(value);
1364 
1365 	return len;
1366 }
1367 
1368 static struct netdev_queue_attribute bql_hold_time_attribute __ro_after_init
1369 	= __ATTR(hold_time, 0644,
1370 		 bql_show_hold_time, bql_set_hold_time);
1371 
bql_show_inflight(struct netdev_queue * queue,char * buf)1372 static ssize_t bql_show_inflight(struct netdev_queue *queue,
1373 				 char *buf)
1374 {
1375 	struct dql *dql = &queue->dql;
1376 
1377 	return sprintf(buf, "%u\n", dql->num_queued - dql->num_completed);
1378 }
1379 
1380 static struct netdev_queue_attribute bql_inflight_attribute __ro_after_init =
1381 	__ATTR(inflight, 0444, bql_show_inflight, NULL);
1382 
1383 #define BQL_ATTR(NAME, FIELD)						\
1384 static ssize_t bql_show_ ## NAME(struct netdev_queue *queue,		\
1385 				 char *buf)				\
1386 {									\
1387 	return bql_show(buf, queue->dql.FIELD);				\
1388 }									\
1389 									\
1390 static ssize_t bql_set_ ## NAME(struct netdev_queue *queue,		\
1391 				const char *buf, size_t len)		\
1392 {									\
1393 	return bql_set(buf, len, &queue->dql.FIELD);			\
1394 }									\
1395 									\
1396 static struct netdev_queue_attribute bql_ ## NAME ## _attribute __ro_after_init \
1397 	= __ATTR(NAME, 0644,				\
1398 		 bql_show_ ## NAME, bql_set_ ## NAME)
1399 
1400 BQL_ATTR(limit, limit);
1401 BQL_ATTR(limit_max, max_limit);
1402 BQL_ATTR(limit_min, min_limit);
1403 
1404 static struct attribute *dql_attrs[] __ro_after_init = {
1405 	&bql_limit_attribute.attr,
1406 	&bql_limit_max_attribute.attr,
1407 	&bql_limit_min_attribute.attr,
1408 	&bql_hold_time_attribute.attr,
1409 	&bql_inflight_attribute.attr,
1410 	NULL
1411 };
1412 
1413 static const struct attribute_group dql_group = {
1414 	.name  = "byte_queue_limits",
1415 	.attrs  = dql_attrs,
1416 };
1417 #endif /* CONFIG_BQL */
1418 
1419 #ifdef CONFIG_XPS
xps_queue_show(struct net_device * dev,unsigned int index,int tc,char * buf,enum xps_map_type type)1420 static ssize_t xps_queue_show(struct net_device *dev, unsigned int index,
1421 			      int tc, char *buf, enum xps_map_type type)
1422 {
1423 	struct xps_dev_maps *dev_maps;
1424 	unsigned long *mask;
1425 	unsigned int nr_ids;
1426 	int j, len;
1427 
1428 	rcu_read_lock();
1429 	dev_maps = rcu_dereference(dev->xps_maps[type]);
1430 
1431 	/* Default to nr_cpu_ids/dev->num_rx_queues and do not just return 0
1432 	 * when dev_maps hasn't been allocated yet, to be backward compatible.
1433 	 */
1434 	nr_ids = dev_maps ? dev_maps->nr_ids :
1435 		 (type == XPS_CPUS ? nr_cpu_ids : dev->num_rx_queues);
1436 
1437 	mask = bitmap_zalloc(nr_ids, GFP_NOWAIT);
1438 	if (!mask) {
1439 		rcu_read_unlock();
1440 		return -ENOMEM;
1441 	}
1442 
1443 	if (!dev_maps || tc >= dev_maps->num_tc)
1444 		goto out_no_maps;
1445 
1446 	for (j = 0; j < nr_ids; j++) {
1447 		int i, tci = j * dev_maps->num_tc + tc;
1448 		struct xps_map *map;
1449 
1450 		map = rcu_dereference(dev_maps->attr_map[tci]);
1451 		if (!map)
1452 			continue;
1453 
1454 		for (i = map->len; i--;) {
1455 			if (map->queues[i] == index) {
1456 				__set_bit(j, mask);
1457 				break;
1458 			}
1459 		}
1460 	}
1461 out_no_maps:
1462 	rcu_read_unlock();
1463 
1464 	len = bitmap_print_to_pagebuf(false, buf, mask, nr_ids);
1465 	bitmap_free(mask);
1466 
1467 	return len < PAGE_SIZE ? len : -EINVAL;
1468 }
1469 
xps_cpus_show(struct netdev_queue * queue,char * buf)1470 static ssize_t xps_cpus_show(struct netdev_queue *queue, char *buf)
1471 {
1472 	struct net_device *dev = queue->dev;
1473 	unsigned int index;
1474 	int len, tc;
1475 
1476 	if (!netif_is_multiqueue(dev))
1477 		return -ENOENT;
1478 
1479 	index = get_netdev_queue_index(queue);
1480 
1481 	if (!rtnl_trylock())
1482 		return restart_syscall();
1483 
1484 	/* If queue belongs to subordinate dev use its map */
1485 	dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev;
1486 
1487 	tc = netdev_txq_to_tc(dev, index);
1488 	if (tc < 0) {
1489 		rtnl_unlock();
1490 		return -EINVAL;
1491 	}
1492 
1493 	/* Make sure the subordinate device can't be freed */
1494 	get_device(&dev->dev);
1495 	rtnl_unlock();
1496 
1497 	len = xps_queue_show(dev, index, tc, buf, XPS_CPUS);
1498 
1499 	put_device(&dev->dev);
1500 	return len;
1501 }
1502 
xps_cpus_store(struct netdev_queue * queue,const char * buf,size_t len)1503 static ssize_t xps_cpus_store(struct netdev_queue *queue,
1504 			      const char *buf, size_t len)
1505 {
1506 	struct net_device *dev = queue->dev;
1507 	unsigned int index;
1508 	cpumask_var_t mask;
1509 	int err;
1510 
1511 	if (!netif_is_multiqueue(dev))
1512 		return -ENOENT;
1513 
1514 	if (!capable(CAP_NET_ADMIN))
1515 		return -EPERM;
1516 
1517 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
1518 		return -ENOMEM;
1519 
1520 	index = get_netdev_queue_index(queue);
1521 
1522 	err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
1523 	if (err) {
1524 		free_cpumask_var(mask);
1525 		return err;
1526 	}
1527 
1528 	if (!rtnl_trylock()) {
1529 		free_cpumask_var(mask);
1530 		return restart_syscall();
1531 	}
1532 
1533 	err = netif_set_xps_queue(dev, mask, index);
1534 	rtnl_unlock();
1535 
1536 	free_cpumask_var(mask);
1537 
1538 	return err ? : len;
1539 }
1540 
1541 static struct netdev_queue_attribute xps_cpus_attribute __ro_after_init
1542 	= __ATTR_RW(xps_cpus);
1543 
xps_rxqs_show(struct netdev_queue * queue,char * buf)1544 static ssize_t xps_rxqs_show(struct netdev_queue *queue, char *buf)
1545 {
1546 	struct net_device *dev = queue->dev;
1547 	unsigned int index;
1548 	int tc;
1549 
1550 	index = get_netdev_queue_index(queue);
1551 
1552 	if (!rtnl_trylock())
1553 		return restart_syscall();
1554 
1555 	tc = netdev_txq_to_tc(dev, index);
1556 	rtnl_unlock();
1557 	if (tc < 0)
1558 		return -EINVAL;
1559 
1560 	return xps_queue_show(dev, index, tc, buf, XPS_RXQS);
1561 }
1562 
xps_rxqs_store(struct netdev_queue * queue,const char * buf,size_t len)1563 static ssize_t xps_rxqs_store(struct netdev_queue *queue, const char *buf,
1564 			      size_t len)
1565 {
1566 	struct net_device *dev = queue->dev;
1567 	struct net *net = dev_net(dev);
1568 	unsigned long *mask;
1569 	unsigned int index;
1570 	int err;
1571 
1572 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1573 		return -EPERM;
1574 
1575 	mask = bitmap_zalloc(dev->num_rx_queues, GFP_KERNEL);
1576 	if (!mask)
1577 		return -ENOMEM;
1578 
1579 	index = get_netdev_queue_index(queue);
1580 
1581 	err = bitmap_parse(buf, len, mask, dev->num_rx_queues);
1582 	if (err) {
1583 		bitmap_free(mask);
1584 		return err;
1585 	}
1586 
1587 	if (!rtnl_trylock()) {
1588 		bitmap_free(mask);
1589 		return restart_syscall();
1590 	}
1591 
1592 	cpus_read_lock();
1593 	err = __netif_set_xps_queue(dev, mask, index, XPS_RXQS);
1594 	cpus_read_unlock();
1595 
1596 	rtnl_unlock();
1597 
1598 	bitmap_free(mask);
1599 	return err ? : len;
1600 }
1601 
1602 static struct netdev_queue_attribute xps_rxqs_attribute __ro_after_init
1603 	= __ATTR_RW(xps_rxqs);
1604 #endif /* CONFIG_XPS */
1605 
1606 static struct attribute *netdev_queue_default_attrs[] __ro_after_init = {
1607 	&queue_trans_timeout.attr,
1608 	&queue_traffic_class.attr,
1609 #ifdef CONFIG_XPS
1610 	&xps_cpus_attribute.attr,
1611 	&xps_rxqs_attribute.attr,
1612 	&queue_tx_maxrate.attr,
1613 #endif
1614 	NULL
1615 };
1616 ATTRIBUTE_GROUPS(netdev_queue_default);
1617 
netdev_queue_release(struct kobject * kobj)1618 static void netdev_queue_release(struct kobject *kobj)
1619 {
1620 	struct netdev_queue *queue = to_netdev_queue(kobj);
1621 
1622 	memset(kobj, 0, sizeof(*kobj));
1623 	dev_put_track(queue->dev, &queue->dev_tracker);
1624 }
1625 
netdev_queue_namespace(struct kobject * kobj)1626 static const void *netdev_queue_namespace(struct kobject *kobj)
1627 {
1628 	struct netdev_queue *queue = to_netdev_queue(kobj);
1629 	struct device *dev = &queue->dev->dev;
1630 	const void *ns = NULL;
1631 
1632 	if (dev->class && dev->class->ns_type)
1633 		ns = dev->class->namespace(dev);
1634 
1635 	return ns;
1636 }
1637 
netdev_queue_get_ownership(struct kobject * kobj,kuid_t * uid,kgid_t * gid)1638 static void netdev_queue_get_ownership(struct kobject *kobj,
1639 				       kuid_t *uid, kgid_t *gid)
1640 {
1641 	const struct net *net = netdev_queue_namespace(kobj);
1642 
1643 	net_ns_get_ownership(net, uid, gid);
1644 }
1645 
1646 static struct kobj_type netdev_queue_ktype __ro_after_init = {
1647 	.sysfs_ops = &netdev_queue_sysfs_ops,
1648 	.release = netdev_queue_release,
1649 	.default_groups = netdev_queue_default_groups,
1650 	.namespace = netdev_queue_namespace,
1651 	.get_ownership = netdev_queue_get_ownership,
1652 };
1653 
netdev_queue_add_kobject(struct net_device * dev,int index)1654 static int netdev_queue_add_kobject(struct net_device *dev, int index)
1655 {
1656 	struct netdev_queue *queue = dev->_tx + index;
1657 	struct kobject *kobj = &queue->kobj;
1658 	int error = 0;
1659 
1660 	/* Kobject_put later will trigger netdev_queue_release call
1661 	 * which decreases dev refcount: Take that reference here
1662 	 */
1663 	dev_hold_track(queue->dev, &queue->dev_tracker, GFP_KERNEL);
1664 
1665 	kobj->kset = dev->queues_kset;
1666 	error = kobject_init_and_add(kobj, &netdev_queue_ktype, NULL,
1667 				     "tx-%u", index);
1668 	if (error)
1669 		goto err;
1670 
1671 #ifdef CONFIG_BQL
1672 	error = sysfs_create_group(kobj, &dql_group);
1673 	if (error)
1674 		goto err;
1675 #endif
1676 
1677 	kobject_uevent(kobj, KOBJ_ADD);
1678 	return 0;
1679 
1680 err:
1681 	kobject_put(kobj);
1682 	return error;
1683 }
1684 
tx_queue_change_owner(struct net_device * ndev,int index,kuid_t kuid,kgid_t kgid)1685 static int tx_queue_change_owner(struct net_device *ndev, int index,
1686 				 kuid_t kuid, kgid_t kgid)
1687 {
1688 	struct netdev_queue *queue = ndev->_tx + index;
1689 	struct kobject *kobj = &queue->kobj;
1690 	int error;
1691 
1692 	error = sysfs_change_owner(kobj, kuid, kgid);
1693 	if (error)
1694 		return error;
1695 
1696 #ifdef CONFIG_BQL
1697 	error = sysfs_group_change_owner(kobj, &dql_group, kuid, kgid);
1698 #endif
1699 	return error;
1700 }
1701 #endif /* CONFIG_SYSFS */
1702 
1703 int
netdev_queue_update_kobjects(struct net_device * dev,int old_num,int new_num)1704 netdev_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
1705 {
1706 #ifdef CONFIG_SYSFS
1707 	int i;
1708 	int error = 0;
1709 
1710 	/* Tx queue kobjects are allowed to be updated when a device is being
1711 	 * unregistered, but solely to remove queues from qdiscs. Any path
1712 	 * adding queues should be fixed.
1713 	 */
1714 	WARN(dev->reg_state == NETREG_UNREGISTERING && new_num > old_num,
1715 	     "New queues can't be registered after device unregistration.");
1716 
1717 	for (i = old_num; i < new_num; i++) {
1718 		error = netdev_queue_add_kobject(dev, i);
1719 		if (error) {
1720 			new_num = old_num;
1721 			break;
1722 		}
1723 	}
1724 
1725 	while (--i >= new_num) {
1726 		struct netdev_queue *queue = dev->_tx + i;
1727 
1728 		if (!refcount_read(&dev_net(dev)->ns.count))
1729 			queue->kobj.uevent_suppress = 1;
1730 #ifdef CONFIG_BQL
1731 		sysfs_remove_group(&queue->kobj, &dql_group);
1732 #endif
1733 		kobject_put(&queue->kobj);
1734 	}
1735 
1736 	return error;
1737 #else
1738 	return 0;
1739 #endif /* CONFIG_SYSFS */
1740 }
1741 
net_tx_queue_change_owner(struct net_device * dev,int num,kuid_t kuid,kgid_t kgid)1742 static int net_tx_queue_change_owner(struct net_device *dev, int num,
1743 				     kuid_t kuid, kgid_t kgid)
1744 {
1745 #ifdef CONFIG_SYSFS
1746 	int error = 0;
1747 	int i;
1748 
1749 	for (i = 0; i < num; i++) {
1750 		error = tx_queue_change_owner(dev, i, kuid, kgid);
1751 		if (error)
1752 			break;
1753 	}
1754 
1755 	return error;
1756 #else
1757 	return 0;
1758 #endif /* CONFIG_SYSFS */
1759 }
1760 
register_queue_kobjects(struct net_device * dev)1761 static int register_queue_kobjects(struct net_device *dev)
1762 {
1763 	int error = 0, txq = 0, rxq = 0, real_rx = 0, real_tx = 0;
1764 
1765 #ifdef CONFIG_SYSFS
1766 	dev->queues_kset = kset_create_and_add("queues",
1767 					       NULL, &dev->dev.kobj);
1768 	if (!dev->queues_kset)
1769 		return -ENOMEM;
1770 	real_rx = dev->real_num_rx_queues;
1771 #endif
1772 	real_tx = dev->real_num_tx_queues;
1773 
1774 	error = net_rx_queue_update_kobjects(dev, 0, real_rx);
1775 	if (error)
1776 		goto error;
1777 	rxq = real_rx;
1778 
1779 	error = netdev_queue_update_kobjects(dev, 0, real_tx);
1780 	if (error)
1781 		goto error;
1782 	txq = real_tx;
1783 
1784 	return 0;
1785 
1786 error:
1787 	netdev_queue_update_kobjects(dev, txq, 0);
1788 	net_rx_queue_update_kobjects(dev, rxq, 0);
1789 #ifdef CONFIG_SYSFS
1790 	kset_unregister(dev->queues_kset);
1791 #endif
1792 	return error;
1793 }
1794 
queue_change_owner(struct net_device * ndev,kuid_t kuid,kgid_t kgid)1795 static int queue_change_owner(struct net_device *ndev, kuid_t kuid, kgid_t kgid)
1796 {
1797 	int error = 0, real_rx = 0, real_tx = 0;
1798 
1799 #ifdef CONFIG_SYSFS
1800 	if (ndev->queues_kset) {
1801 		error = sysfs_change_owner(&ndev->queues_kset->kobj, kuid, kgid);
1802 		if (error)
1803 			return error;
1804 	}
1805 	real_rx = ndev->real_num_rx_queues;
1806 #endif
1807 	real_tx = ndev->real_num_tx_queues;
1808 
1809 	error = net_rx_queue_change_owner(ndev, real_rx, kuid, kgid);
1810 	if (error)
1811 		return error;
1812 
1813 	error = net_tx_queue_change_owner(ndev, real_tx, kuid, kgid);
1814 	if (error)
1815 		return error;
1816 
1817 	return 0;
1818 }
1819 
remove_queue_kobjects(struct net_device * dev)1820 static void remove_queue_kobjects(struct net_device *dev)
1821 {
1822 	int real_rx = 0, real_tx = 0;
1823 
1824 #ifdef CONFIG_SYSFS
1825 	real_rx = dev->real_num_rx_queues;
1826 #endif
1827 	real_tx = dev->real_num_tx_queues;
1828 
1829 	net_rx_queue_update_kobjects(dev, real_rx, 0);
1830 	netdev_queue_update_kobjects(dev, real_tx, 0);
1831 
1832 	dev->real_num_rx_queues = 0;
1833 	dev->real_num_tx_queues = 0;
1834 #ifdef CONFIG_SYSFS
1835 	kset_unregister(dev->queues_kset);
1836 #endif
1837 }
1838 
net_current_may_mount(void)1839 static bool net_current_may_mount(void)
1840 {
1841 	struct net *net = current->nsproxy->net_ns;
1842 
1843 	return ns_capable(net->user_ns, CAP_SYS_ADMIN);
1844 }
1845 
net_grab_current_ns(void)1846 static void *net_grab_current_ns(void)
1847 {
1848 	struct net *ns = current->nsproxy->net_ns;
1849 #ifdef CONFIG_NET_NS
1850 	if (ns)
1851 		refcount_inc(&ns->passive);
1852 #endif
1853 	return ns;
1854 }
1855 
net_initial_ns(void)1856 static const void *net_initial_ns(void)
1857 {
1858 	return &init_net;
1859 }
1860 
net_netlink_ns(struct sock * sk)1861 static const void *net_netlink_ns(struct sock *sk)
1862 {
1863 	return sock_net(sk);
1864 }
1865 
1866 const struct kobj_ns_type_operations net_ns_type_operations = {
1867 	.type = KOBJ_NS_TYPE_NET,
1868 	.current_may_mount = net_current_may_mount,
1869 	.grab_current_ns = net_grab_current_ns,
1870 	.netlink_ns = net_netlink_ns,
1871 	.initial_ns = net_initial_ns,
1872 	.drop_ns = net_drop_ns,
1873 };
1874 EXPORT_SYMBOL_GPL(net_ns_type_operations);
1875 
netdev_uevent(struct device * d,struct kobj_uevent_env * env)1876 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
1877 {
1878 	struct net_device *dev = to_net_dev(d);
1879 	int retval;
1880 
1881 	/* pass interface to uevent. */
1882 	retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
1883 	if (retval)
1884 		goto exit;
1885 
1886 	/* pass ifindex to uevent.
1887 	 * ifindex is useful as it won't change (interface name may change)
1888 	 * and is what RtNetlink uses natively.
1889 	 */
1890 	retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
1891 
1892 exit:
1893 	return retval;
1894 }
1895 
1896 /*
1897  *	netdev_release -- destroy and free a dead device.
1898  *	Called when last reference to device kobject is gone.
1899  */
netdev_release(struct device * d)1900 static void netdev_release(struct device *d)
1901 {
1902 	struct net_device *dev = to_net_dev(d);
1903 
1904 	BUG_ON(dev->reg_state != NETREG_RELEASED);
1905 
1906 	/* no need to wait for rcu grace period:
1907 	 * device is dead and about to be freed.
1908 	 */
1909 	kfree(rcu_access_pointer(dev->ifalias));
1910 	netdev_freemem(dev);
1911 }
1912 
net_namespace(struct device * d)1913 static const void *net_namespace(struct device *d)
1914 {
1915 	struct net_device *dev = to_net_dev(d);
1916 
1917 	return dev_net(dev);
1918 }
1919 
net_get_ownership(struct device * d,kuid_t * uid,kgid_t * gid)1920 static void net_get_ownership(struct device *d, kuid_t *uid, kgid_t *gid)
1921 {
1922 	struct net_device *dev = to_net_dev(d);
1923 	const struct net *net = dev_net(dev);
1924 
1925 	net_ns_get_ownership(net, uid, gid);
1926 }
1927 
1928 static struct class net_class __ro_after_init = {
1929 	.name = "net",
1930 	.dev_release = netdev_release,
1931 	.dev_groups = net_class_groups,
1932 	.dev_uevent = netdev_uevent,
1933 	.ns_type = &net_ns_type_operations,
1934 	.namespace = net_namespace,
1935 	.get_ownership = net_get_ownership,
1936 };
1937 
1938 #ifdef CONFIG_OF
of_dev_node_match(struct device * dev,const void * data)1939 static int of_dev_node_match(struct device *dev, const void *data)
1940 {
1941 	for (; dev; dev = dev->parent) {
1942 		if (dev->of_node == data)
1943 			return 1;
1944 	}
1945 
1946 	return 0;
1947 }
1948 
1949 /*
1950  * of_find_net_device_by_node - lookup the net device for the device node
1951  * @np: OF device node
1952  *
1953  * Looks up the net_device structure corresponding with the device node.
1954  * If successful, returns a pointer to the net_device with the embedded
1955  * struct device refcount incremented by one, or NULL on failure. The
1956  * refcount must be dropped when done with the net_device.
1957  */
of_find_net_device_by_node(struct device_node * np)1958 struct net_device *of_find_net_device_by_node(struct device_node *np)
1959 {
1960 	struct device *dev;
1961 
1962 	dev = class_find_device(&net_class, NULL, np, of_dev_node_match);
1963 	if (!dev)
1964 		return NULL;
1965 
1966 	return to_net_dev(dev);
1967 }
1968 EXPORT_SYMBOL(of_find_net_device_by_node);
1969 #endif
1970 
1971 /* Delete sysfs entries but hold kobject reference until after all
1972  * netdev references are gone.
1973  */
netdev_unregister_kobject(struct net_device * ndev)1974 void netdev_unregister_kobject(struct net_device *ndev)
1975 {
1976 	struct device *dev = &ndev->dev;
1977 
1978 	if (!refcount_read(&dev_net(ndev)->ns.count))
1979 		dev_set_uevent_suppress(dev, 1);
1980 
1981 	kobject_get(&dev->kobj);
1982 
1983 	remove_queue_kobjects(ndev);
1984 
1985 	pm_runtime_set_memalloc_noio(dev, false);
1986 
1987 	device_del(dev);
1988 }
1989 
1990 /* Create sysfs entries for network device. */
netdev_register_kobject(struct net_device * ndev)1991 int netdev_register_kobject(struct net_device *ndev)
1992 {
1993 	struct device *dev = &ndev->dev;
1994 	const struct attribute_group **groups = ndev->sysfs_groups;
1995 	int error = 0;
1996 
1997 	device_initialize(dev);
1998 	dev->class = &net_class;
1999 	dev->platform_data = ndev;
2000 	dev->groups = groups;
2001 
2002 	dev_set_name(dev, "%s", ndev->name);
2003 
2004 #ifdef CONFIG_SYSFS
2005 	/* Allow for a device specific group */
2006 	if (*groups)
2007 		groups++;
2008 
2009 	*groups++ = &netstat_group;
2010 
2011 	if (wireless_group_needed(ndev))
2012 		*groups++ = &wireless_group;
2013 #endif /* CONFIG_SYSFS */
2014 
2015 	error = device_add(dev);
2016 	if (error)
2017 		return error;
2018 
2019 	error = register_queue_kobjects(ndev);
2020 	if (error) {
2021 		device_del(dev);
2022 		return error;
2023 	}
2024 
2025 	pm_runtime_set_memalloc_noio(dev, true);
2026 
2027 	return error;
2028 }
2029 
2030 /* Change owner for sysfs entries when moving network devices across network
2031  * namespaces owned by different user namespaces.
2032  */
netdev_change_owner(struct net_device * ndev,const struct net * net_old,const struct net * net_new)2033 int netdev_change_owner(struct net_device *ndev, const struct net *net_old,
2034 			const struct net *net_new)
2035 {
2036 	kuid_t old_uid = GLOBAL_ROOT_UID, new_uid = GLOBAL_ROOT_UID;
2037 	kgid_t old_gid = GLOBAL_ROOT_GID, new_gid = GLOBAL_ROOT_GID;
2038 	struct device *dev = &ndev->dev;
2039 	int error;
2040 
2041 	net_ns_get_ownership(net_old, &old_uid, &old_gid);
2042 	net_ns_get_ownership(net_new, &new_uid, &new_gid);
2043 
2044 	/* The network namespace was changed but the owning user namespace is
2045 	 * identical so there's no need to change the owner of sysfs entries.
2046 	 */
2047 	if (uid_eq(old_uid, new_uid) && gid_eq(old_gid, new_gid))
2048 		return 0;
2049 
2050 	error = device_change_owner(dev, new_uid, new_gid);
2051 	if (error)
2052 		return error;
2053 
2054 	error = queue_change_owner(ndev, new_uid, new_gid);
2055 	if (error)
2056 		return error;
2057 
2058 	return 0;
2059 }
2060 
netdev_class_create_file_ns(const struct class_attribute * class_attr,const void * ns)2061 int netdev_class_create_file_ns(const struct class_attribute *class_attr,
2062 				const void *ns)
2063 {
2064 	return class_create_file_ns(&net_class, class_attr, ns);
2065 }
2066 EXPORT_SYMBOL(netdev_class_create_file_ns);
2067 
netdev_class_remove_file_ns(const struct class_attribute * class_attr,const void * ns)2068 void netdev_class_remove_file_ns(const struct class_attribute *class_attr,
2069 				 const void *ns)
2070 {
2071 	class_remove_file_ns(&net_class, class_attr, ns);
2072 }
2073 EXPORT_SYMBOL(netdev_class_remove_file_ns);
2074 
netdev_kobject_init(void)2075 int __init netdev_kobject_init(void)
2076 {
2077 	kobj_ns_type_register(&net_ns_type_operations);
2078 	return class_register(&net_class);
2079 }
2080