summaryrefslogtreecommitdiff
path: root/net/ethtool/netlink.c
blob: f61654b8f2103ed574beabe04eeed2fbc23e3c68 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
// SPDX-License-Identifier: GPL-2.0-only

#include <net/sock.h>
#include <linux/ethtool_netlink.h>
#include "netlink.h"

static struct genl_family ethtool_genl_family;

static bool ethnl_ok __read_mostly;
static u32 ethnl_bcast_seq;

static const struct nla_policy ethnl_header_policy[ETHTOOL_A_HEADER_MAX + 1] = {
	[ETHTOOL_A_HEADER_UNSPEC]	= { .type = NLA_REJECT },
	[ETHTOOL_A_HEADER_DEV_INDEX]	= { .type = NLA_U32 },
	[ETHTOOL_A_HEADER_DEV_NAME]	= { .type = NLA_NUL_STRING,
					    .len = ALTIFNAMSIZ - 1 },
	[ETHTOOL_A_HEADER_FLAGS]	= { .type = NLA_U32 },
};

/**
 * ethnl_parse_header_dev_get() - parse request header
 * @req_info:    structure to put results into
 * @header:      nest attribute with request header
 * @net:         request netns
 * @extack:      netlink extack for error reporting
 * @require_dev: fail if no device identified in header
 *
 * Parse request header in nested attribute @nest and puts results into
 * the structure pointed to by @req_info. Extack from @info is used for error
 * reporting. If req_info->dev is not null on return, reference to it has
 * been taken. If error is returned, *req_info is null initialized and no
 * reference is held.
 *
 * Return: 0 on success or negative error code
 */
int ethnl_parse_header_dev_get(struct ethnl_req_info *req_info,
			       const struct nlattr *header, struct net *net,
			       struct netlink_ext_ack *extack, bool require_dev)
{
	struct nlattr *tb[ETHTOOL_A_HEADER_MAX + 1];
	const struct nlattr *devname_attr;
	struct net_device *dev = NULL;
	int ret;

	if (!header) {
		NL_SET_ERR_MSG(extack, "request header missing");
		return -EINVAL;
	}
	ret = nla_parse_nested(tb, ETHTOOL_A_HEADER_MAX, header,
			       ethnl_header_policy, extack);
	if (ret < 0)
		return ret;
	devname_attr = tb[ETHTOOL_A_HEADER_DEV_NAME];

	if (tb[ETHTOOL_A_HEADER_DEV_INDEX]) {
		u32 ifindex = nla_get_u32(tb[ETHTOOL_A_HEADER_DEV_INDEX]);

		dev = dev_get_by_index(net, ifindex);
		if (!dev) {
			NL_SET_ERR_MSG_ATTR(extack,
					    tb[ETHTOOL_A_HEADER_DEV_INDEX],
					    "no device matches ifindex");
			return -ENODEV;
		}
		/* if both ifindex and ifname are passed, they must match */
		if (devname_attr &&
		    strncmp(dev->name, nla_data(devname_attr), IFNAMSIZ)) {
			dev_put(dev);
			NL_SET_ERR_MSG_ATTR(extack, header,
					    "ifindex and name do not match");
			return -ENODEV;
		}
	} else if (devname_attr) {
		dev = dev_get_by_name(net, nla_data(devname_attr));
		if (!dev) {
			NL_SET_ERR_MSG_ATTR(extack, devname_attr,
					    "no device matches name");
			return -ENODEV;
		}
	} else if (require_dev) {
		NL_SET_ERR_MSG_ATTR(extack, header,
				    "neither ifindex nor name specified");
		return -EINVAL;
	}

	if (dev && !netif_device_present(dev)) {
		dev_put(dev);
		NL_SET_ERR_MSG(extack, "device not present");
		return -ENODEV;
	}

	req_info->dev = dev;
	if (tb[ETHTOOL_A_HEADER_FLAGS])
		req_info->flags = nla_get_u32(tb[ETHTOOL_A_HEADER_FLAGS]);

	return 0;
}

/**
 * ethnl_fill_reply_header() - Put common header into a reply message
 * @skb:      skb with the message
 * @dev:      network device to describe in header
 * @attrtype: attribute type to use for the nest
 *
 * Create a nested attribute with attributes describing given network device.
 *
 * Return: 0 on success, error value (-EMSGSIZE only) on error
 */
int ethnl_fill_reply_header(struct sk_buff *skb, struct net_device *dev,
			    u16 attrtype)
{
	struct nlattr *nest;

	if (!dev)
		return 0;
	nest = nla_nest_start(skb, attrtype);
	if (!nest)
		return -EMSGSIZE;

	if (nla_put_u32(skb, ETHTOOL_A_HEADER_DEV_INDEX, (u32)dev->ifindex) ||
	    nla_put_string(skb, ETHTOOL_A_HEADER_DEV_NAME, dev->name))
		goto nla_put_failure;
	/* If more attributes are put into reply header, ethnl_header_size()
	 * must be updated to account for them.
	 */

	nla_nest_end(skb, nest);
	return 0;

nla_put_failure:
	nla_nest_cancel(skb, nest);
	return -EMSGSIZE;
}

/**
 * ethnl_reply_init() - Create skb for a reply and fill device identification
 * @payload:      payload length (without netlink and genetlink header)
 * @dev:          device the reply is about (may be null)
 * @cmd:          ETHTOOL_MSG_* message type for reply
 * @hdr_attrtype: attribute type for common header
 * @info:         genetlink info of the received packet we respond to
 * @ehdrp:        place to store payload pointer returned by genlmsg_new()
 *
 * Return: pointer to allocated skb on success, NULL on error
 */
struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd,
				 u16 hdr_attrtype, struct genl_info *info,
				 void **ehdrp)
{
	struct sk_buff *skb;

	skb = genlmsg_new(payload, GFP_KERNEL);
	if (!skb)
		goto err;
	*ehdrp = genlmsg_put_reply(skb, info, &ethtool_genl_family, 0, cmd);
	if (!*ehdrp)
		goto err_free;

	if (dev) {
		int ret;

		ret = ethnl_fill_reply_header(skb, dev, hdr_attrtype);
		if (ret < 0)
			goto err_free;
	}
	return skb;

err_free:
	nlmsg_free(skb);
err:
	if (info)
		GENL_SET_ERR_MSG(info, "failed to setup reply message");
	return NULL;
}

static void *ethnl_bcastmsg_put(struct sk_buff *skb, u8 cmd)
{
	return genlmsg_put(skb, 0, ++ethnl_bcast_seq, &ethtool_genl_family, 0,
			   cmd);
}

static int ethnl_multicast(struct sk_buff *skb, struct net_device *dev)
{
	return genlmsg_multicast_netns(&ethtool_genl_family, dev_net(dev), skb,
				       0, ETHNL_MCGRP_MONITOR, GFP_KERNEL);
}

/* GET request helpers */

/**
 * struct ethnl_dump_ctx - context structure for generic dumpit() callback
 * @ops:        request ops of currently processed message type
 * @req_info:   parsed request header of processed request
 * @reply_data: data needed to compose the reply
 * @pos_hash:   saved iteration position - hashbucket
 * @pos_idx:    saved iteration position - index
 *
 * These parameters are kept in struct netlink_callback as context preserved
 * between iterations. They are initialized by ethnl_default_start() and used
 * in ethnl_default_dumpit() and ethnl_default_done().
 */
struct ethnl_dump_ctx {
	const struct ethnl_request_ops	*ops;
	struct ethnl_req_info		*req_info;
	struct ethnl_reply_data		*reply_data;
	int				pos_hash;
	int				pos_idx;
};

static const struct ethnl_request_ops *
ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
	[ETHTOOL_MSG_STRSET_GET]	= &ethnl_strset_request_ops,
	[ETHTOOL_MSG_LINKINFO_GET]	= &ethnl_linkinfo_request_ops,
	[ETHTOOL_MSG_LINKMODES_GET]	= &ethnl_linkmodes_request_ops,
	[ETHTOOL_MSG_LINKSTATE_GET]	= &ethnl_linkstate_request_ops,
	[ETHTOOL_MSG_DEBUG_GET]		= &ethnl_debug_request_ops,
	[ETHTOOL_MSG_WOL_GET]		= &ethnl_wol_request_ops,
	[ETHTOOL_MSG_FEATURES_GET]	= &ethnl_features_request_ops,
	[ETHTOOL_MSG_PRIVFLAGS_GET]	= &ethnl_privflags_request_ops,
	[ETHTOOL_MSG_RINGS_GET]		= &ethnl_rings_request_ops,
	[ETHTOOL_MSG_CHANNELS_GET]	= &ethnl_channels_request_ops,
};

static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
{
	return (struct ethnl_dump_ctx *)cb->ctx;
}

/**
 * ethnl_default_parse() - Parse request message
 * @req_info:    pointer to structure to put data into
 * @nlhdr:       pointer to request message header
 * @net:         request netns
 * @request_ops: struct request_ops for request type
 * @extack:      netlink extack for error reporting
 * @require_dev: fail if no device identified in header
 *
 * Parse universal request header and call request specific ->parse_request()
 * callback (if defined) to parse the rest of the message.
 *
 * Return: 0 on success or negative error code
 */
static int ethnl_default_parse(struct ethnl_req_info *req_info,
			       const struct nlmsghdr *nlhdr, struct net *net,
			       const struct ethnl_request_ops *request_ops,
			       struct netlink_ext_ack *extack, bool require_dev)
{
	struct nlattr **tb;
	int ret;

	tb = kmalloc_array(request_ops->max_attr + 1, sizeof(tb[0]),
			   GFP_KERNEL);
	if (!tb)
		return -ENOMEM;

	ret = nlmsg_parse(nlhdr, GENL_HDRLEN, tb, request_ops->max_attr,
			  request_ops->request_policy, extack);
	if (ret < 0)
		goto out;
	ret = ethnl_parse_header_dev_get(req_info, tb[request_ops->hdr_attr],
					 net, extack, require_dev);
	if (ret < 0)
		goto out;

	if (request_ops->parse_request) {
		ret = request_ops->parse_request(req_info, tb, extack);
		if (ret < 0)
			goto out;
	}

	ret = 0;
out:
	kfree(tb);
	return ret;
}

/**
 * ethnl_init_reply_data() - Initialize reply data for GET request
 * @reply_data: pointer to embedded struct ethnl_reply_data
 * @ops:        instance of struct ethnl_request_ops describing the layout
 * @dev:        network device to initialize the reply for
 *
 * Fills the reply data part with zeros and sets the dev member. Must be called
 * before calling the ->fill_reply() callback (for each iteration when handling
 * dump requests).
 */
static void ethnl_init_reply_data(struct ethnl_reply_data *reply_data,
				  const struct ethnl_request_ops *ops,
				  struct net_device *dev)
{
	memset(reply_data, 0, ops->reply_data_size);
	reply_data->dev = dev;
}

/* default ->doit() handler for GET type requests */
static int ethnl_default_doit(struct sk_buff *skb, struct genl_info *info)
{
	struct ethnl_reply_data *reply_data = NULL;
	struct ethnl_req_info *req_info = NULL;
	const u8 cmd = info->genlhdr->cmd;
	const struct ethnl_request_ops *ops;
	struct sk_buff *rskb;
	void *reply_payload;
	int reply_len;
	int ret;

	ops = ethnl_default_requests[cmd];
	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", cmd))
		return -EOPNOTSUPP;
	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
	if (!req_info)
		return -ENOMEM;
	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
	if (!reply_data) {
		kfree(req_info);
		return -ENOMEM;
	}

	ret = ethnl_default_parse(req_info, info->nlhdr, genl_info_net(info), ops,
				  info->extack, !ops->allow_nodev_do);
	if (ret < 0)
		goto err_dev;
	ethnl_init_reply_data(reply_data, ops, req_info->dev);

	rtnl_lock();
	ret = ops->prepare_data(req_info, reply_data, info);
	rtnl_unlock();
	if (ret < 0)
		goto err_cleanup;
	ret = ops->reply_size(req_info, reply_data);
	if (ret < 0)
		goto err_cleanup;
	reply_len = ret;
	ret = -ENOMEM;
	rskb = ethnl_reply_init(reply_len, req_info->dev, ops->reply_cmd,
				ops->hdr_attr, info, &reply_payload);
	if (!rskb)
		goto err_cleanup;
	ret = ops->fill_reply(rskb, req_info, reply_data);
	if (ret < 0)
		goto err_msg;
	if (ops->cleanup_data)
		ops->cleanup_data(reply_data);

	genlmsg_end(rskb, reply_payload);
	if (req_info->dev)
		dev_put(req_info->dev);
	kfree(reply_data);
	kfree(req_info);
	return genlmsg_reply(rskb, info);

err_msg:
	WARN_ONCE(ret == -EMSGSIZE, "calculated message payload length (%d) not sufficient\n", reply_len);
	nlmsg_free(rskb);
err_cleanup:
	if (ops->cleanup_data)
		ops->cleanup_data(reply_data);
err_dev:
	if (req_info->dev)
		dev_put(req_info->dev);
	kfree(reply_data);
	kfree(req_info);
	return ret;
}

static int ethnl_default_dump_one(struct sk_buff *skb, struct net_device *dev,
				  const struct ethnl_dump_ctx *ctx)
{
	int ret;

	ethnl_init_reply_data(ctx->reply_data, ctx->ops, dev);
	rtnl_lock();
	ret = ctx->ops->prepare_data(ctx->req_info, ctx->reply_data, NULL);
	rtnl_unlock();
	if (ret < 0)
		goto out;
	ret = ethnl_fill_reply_header(skb, dev, ctx->ops->hdr_attr);
	if (ret < 0)
		goto out;
	ret = ctx->ops->fill_reply(skb, ctx->req_info, ctx->reply_data);

out:
	if (ctx->ops->cleanup_data)
		ctx->ops->cleanup_data(ctx->reply_data);
	ctx->reply_data->dev = NULL;
	return ret;
}

/* Default ->dumpit() handler for GET requests. Device iteration copied from
 * rtnl_dump_ifinfo(); we have to be more careful about device hashtable
 * persistence as we cannot guarantee to hold RTNL lock through the whole
 * function as rtnetnlink does.
 */
static int ethnl_default_dumpit(struct sk_buff *skb,
				struct netlink_callback *cb)
{
	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
	struct net *net = sock_net(skb->sk);
	int s_idx = ctx->pos_idx;
	int h, idx = 0;
	int ret = 0;
	void *ehdr;

	rtnl_lock();
	for (h = ctx->pos_hash; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
		struct hlist_head *head;
		struct net_device *dev;
		unsigned int seq;

		head = &net->dev_index_head[h];

restart_chain:
		seq = net->dev_base_seq;
		cb->seq = seq;
		idx = 0;
		hlist_for_each_entry(dev, head, index_hlist) {
			if (idx < s_idx)
				goto cont;
			dev_hold(dev);
			rtnl_unlock();

			ehdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
					   cb->nlh->nlmsg_seq,
					   &ethtool_genl_family, 0,
					   ctx->ops->reply_cmd);
			if (!ehdr) {
				dev_put(dev);
				ret = -EMSGSIZE;
				goto out;
			}
			ret = ethnl_default_dump_one(skb, dev, ctx);
			dev_put(dev);
			if (ret < 0) {
				genlmsg_cancel(skb, ehdr);
				if (ret == -EOPNOTSUPP)
					goto lock_and_cont;
				if (likely(skb->len))
					ret = skb->len;
				goto out;
			}
			genlmsg_end(skb, ehdr);
lock_and_cont:
			rtnl_lock();
			if (net->dev_base_seq != seq) {
				s_idx = idx + 1;
				goto restart_chain;
			}
cont:
			idx++;
		}

	}
	rtnl_unlock();

out:
	ctx->pos_hash = h;
	ctx->pos_idx = idx;
	nl_dump_check_consistent(cb, nlmsg_hdr(skb));

	return ret;
}

/* generic ->start() handler for GET requests */
static int ethnl_default_start(struct netlink_callback *cb)
{
	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
	struct ethnl_reply_data *reply_data;
	const struct ethnl_request_ops *ops;
	struct ethnl_req_info *req_info;
	struct genlmsghdr *ghdr;
	int ret;

	BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));

	ghdr = nlmsg_data(cb->nlh);
	ops = ethnl_default_requests[ghdr->cmd];
	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", ghdr->cmd))
		return -EOPNOTSUPP;
	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
	if (!req_info)
		return -ENOMEM;
	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
	if (!reply_data) {
		ret = -ENOMEM;
		goto free_req_info;
	}

	ret = ethnl_default_parse(req_info, cb->nlh, sock_net(cb->skb->sk), ops,
				  cb->extack, false);
	if (req_info->dev) {
		/* We ignore device specification in dump requests but as the
		 * same parser as for non-dump (doit) requests is used, it
		 * would take reference to the device if it finds one
		 */
		dev_put(req_info->dev);
		req_info->dev = NULL;
	}
	if (ret < 0)
		goto free_reply_data;

	ctx->ops = ops;
	ctx->req_info = req_info;
	ctx->reply_data = reply_data;
	ctx->pos_hash = 0;
	ctx->pos_idx = 0;

	return 0;

free_reply_data:
	kfree(reply_data);
free_req_info:
	kfree(req_info);

	return ret;
}

/* default ->done() handler for GET requests */
static int ethnl_default_done(struct netlink_callback *cb)
{
	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);

	kfree(ctx->reply_data);
	kfree(ctx->req_info);

	return 0;
}

static const struct ethnl_request_ops *
ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
	[ETHTOOL_MSG_LINKINFO_NTF]	= &ethnl_linkinfo_request_ops,
	[ETHTOOL_MSG_LINKMODES_NTF]	= &ethnl_linkmodes_request_ops,
	[ETHTOOL_MSG_DEBUG_NTF]		= &ethnl_debug_request_ops,
	[ETHTOOL_MSG_WOL_NTF]		= &ethnl_wol_request_ops,
	[ETHTOOL_MSG_FEATURES_NTF]	= &ethnl_features_request_ops,
	[ETHTOOL_MSG_PRIVFLAGS_NTF]	= &ethnl_privflags_request_ops,
	[ETHTOOL_MSG_RINGS_NTF]		= &ethnl_rings_request_ops,
};

/* default notification handler */
static void ethnl_default_notify(struct net_device *dev, unsigned int cmd,
				 const void *data)
{
	struct ethnl_reply_data *reply_data;
	const struct ethnl_request_ops *ops;
	struct ethnl_req_info *req_info;
	struct sk_buff *skb;
	void *reply_payload;
	int reply_len;
	int ret;

	if (WARN_ONCE(cmd > ETHTOOL_MSG_KERNEL_MAX ||
		      !ethnl_default_notify_ops[cmd],
		      "unexpected notification type %u\n", cmd))
		return;
	ops = ethnl_default_notify_ops[cmd];
	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
	if (!req_info)
		return;
	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
	if (!reply_data) {
		kfree(req_info);
		return;
	}

	req_info->dev = dev;
	req_info->flags |= ETHTOOL_FLAG_COMPACT_BITSETS;

	ethnl_init_reply_data(reply_data, ops, dev);
	ret = ops->prepare_data(req_info, reply_data, NULL);
	if (ret < 0)
		goto err_cleanup;
	ret = ops->reply_size(req_info, reply_data);
	if (ret < 0)
		goto err_cleanup;
	reply_len = ret;
	ret = -ENOMEM;
	skb = genlmsg_new(reply_len, GFP_KERNEL);
	if (!skb)
		goto err_cleanup;
	reply_payload = ethnl_bcastmsg_put(skb, cmd);
	if (!reply_payload)
		goto err_skb;
	ret = ethnl_fill_reply_header(skb, dev, ops->hdr_attr);
	if (ret < 0)
		goto err_msg;
	ret = ops->fill_reply(skb, req_info, reply_data);
	if (ret < 0)
		goto err_msg;
	if (ops->cleanup_data)
		ops->cleanup_data(reply_data);

	genlmsg_end(skb, reply_payload);
	kfree(reply_data);
	kfree(req_info);
	ethnl_multicast(skb, dev);
	return;

err_msg:
	WARN_ONCE(ret == -EMSGSIZE,
		  "calculated message payload length (%d) not sufficient\n",
		  reply_len);
err_skb:
	nlmsg_free(skb);
err_cleanup:
	if (ops->cleanup_data)
		ops->cleanup_data(reply_data);
	kfree(reply_data);
	kfree(req_info);
	return;
}

/* notifications */

typedef void (*ethnl_notify_handler_t)(struct net_device *dev, unsigned int cmd,
				       const void *data);

static const ethnl_notify_handler_t ethnl_notify_handlers[] = {
	[ETHTOOL_MSG_LINKINFO_NTF]	= ethnl_default_notify,
	[ETHTOOL_MSG_LINKMODES_NTF]	= ethnl_default_notify,
	[ETHTOOL_MSG_DEBUG_NTF]		= ethnl_default_notify,
	[ETHTOOL_MSG_WOL_NTF]		= ethnl_default_notify,
	[ETHTOOL_MSG_FEATURES_NTF]	= ethnl_default_notify,
	[ETHTOOL_MSG_PRIVFLAGS_NTF]	= ethnl_default_notify,
	[ETHTOOL_MSG_RINGS_NTF]		= ethnl_default_notify,
};

void ethtool_notify(struct net_device *dev, unsigned int cmd, const void *data)
{
	if (unlikely(!ethnl_ok))
		return;
	ASSERT_RTNL();

	if (likely(cmd < ARRAY_SIZE(ethnl_notify_handlers) &&
		   ethnl_notify_handlers[cmd]))
		ethnl_notify_handlers[cmd](dev, cmd, data);
	else
		WARN_ONCE(1, "notification %u not implemented (dev=%s)\n",
			  cmd, netdev_name(dev));
}
EXPORT_SYMBOL(ethtool_notify);

static void ethnl_notify_features(struct netdev_notifier_info *info)
{
	struct net_device *dev = netdev_notifier_info_to_dev(info);

	ethtool_notify(dev, ETHTOOL_MSG_FEATURES_NTF, NULL);
}

static int ethnl_netdev_event(struct notifier_block *this, unsigned long event,
			      void *ptr)
{
	switch (event) {
	case NETDEV_FEAT_CHANGE:
		ethnl_notify_features(ptr);
		break;
	}

	return NOTIFY_DONE;
}

static struct notifier_block ethnl_netdev_notifier = {
	.notifier_call = ethnl_netdev_event,
};

/* genetlink setup */

static const struct genl_ops ethtool_genl_ops[] = {
	{
		.cmd	= ETHTOOL_MSG_STRSET_GET,
		.doit	= ethnl_default_doit,
		.start	= ethnl_default_start,
		.dumpit	= ethnl_default_dumpit,
		.done	= ethnl_default_done,
	},
	{
		.cmd	= ETHTOOL_MSG_LINKINFO_GET,
		.doit	= ethnl_default_doit,
		.start	= ethnl_default_start,
		.dumpit	= ethnl_default_dumpit,
		.done	= ethnl_default_done,
	},
	{
		.cmd	= ETHTOOL_MSG_LINKINFO_SET,
		.flags	= GENL_UNS_ADMIN_PERM,
		.doit	= ethnl_set_linkinfo,
	},
	{
		.cmd	= ETHTOOL_MSG_LINKMODES_GET,
		.doit	= ethnl_default_doit,
		.start	= ethnl_default_start,
		.dumpit	= ethnl_default_dumpit,
		.done	= ethnl_default_done,
	},
	{
		.cmd	= ETHTOOL_MSG_LINKMODES_SET,
		.flags	= GENL_UNS_ADMIN_PERM,
		.doit	= ethnl_set_linkmodes,
	},
	{
		.cmd	= ETHTOOL_MSG_LINKSTATE_GET,
		.doit	= ethnl_default_doit,
		.start	= ethnl_default_start,
		.dumpit	= ethnl_default_dumpit,
		.done	= ethnl_default_done,
	},
	{
		.cmd	= ETHTOOL_MSG_DEBUG_GET,
		.doit	= ethnl_default_doit,
		.start	= ethnl_default_start,
		.dumpit	= ethnl_default_dumpit,
		.done	= ethnl_default_done,
	},
	{
		.cmd	= ETHTOOL_MSG_DEBUG_SET,
		.flags	= GENL_UNS_ADMIN_PERM,
		.doit	= ethnl_set_debug,
	},
	{
		.cmd	= ETHTOOL_MSG_WOL_GET,
		.flags	= GENL_UNS_ADMIN_PERM,
		.doit	= ethnl_default_doit,
		.start	= ethnl_default_start,
		.dumpit	= ethnl_default_dumpit,
		.done	= ethnl_default_done,
	},
	{
		.cmd	= ETHTOOL_MSG_WOL_SET,
		.flags	= GENL_UNS_ADMIN_PERM,
		.doit	= ethnl_set_wol,
	},
	{
		.cmd	= ETHTOOL_MSG_FEATURES_GET,
		.doit	= ethnl_default_doit,
		.start	= ethnl_default_start,
		.dumpit	= ethnl_default_dumpit,
		.done	= ethnl_default_done,
	},
	{
		.cmd	= ETHTOOL_MSG_FEATURES_SET,
		.flags	= GENL_UNS_ADMIN_PERM,
		.doit	= ethnl_set_features,
	},
	{
		.cmd	= ETHTOOL_MSG_PRIVFLAGS_GET,
		.doit	= ethnl_default_doit,
		.start	= ethnl_default_start,
		.dumpit	= ethnl_default_dumpit,
		.done	= ethnl_default_done,
	},
	{
		.cmd	= ETHTOOL_MSG_PRIVFLAGS_SET,
		.flags	= GENL_UNS_ADMIN_PERM,
		.doit	= ethnl_set_privflags,
	},
	{
		.cmd	= ETHTOOL_MSG_RINGS_GET,
		.doit	= ethnl_default_doit,
		.start	= ethnl_default_start,
		.dumpit	= ethnl_default_dumpit,
		.done	= ethnl_default_done,
	},
	{
		.cmd	= ETHTOOL_MSG_RINGS_SET,
		.flags	= GENL_UNS_ADMIN_PERM,
		.doit	= ethnl_set_rings,
	},
	{
		.cmd	= ETHTOOL_MSG_CHANNELS_GET,
		.doit	= ethnl_default_doit,
		.start	= ethnl_default_start,
		.dumpit	= ethnl_default_dumpit,
		.done	= ethnl_default_done,
	},
	{
		.cmd	= ETHTOOL_MSG_CHANNELS_SET,
		.flags	= GENL_UNS_ADMIN_PERM,
		.doit	= ethnl_set_channels,
	},
};

static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
	[ETHNL_MCGRP_MONITOR] = { .name = ETHTOOL_MCGRP_MONITOR_NAME },
};

static struct genl_family ethtool_genl_family = {
	.name		= ETHTOOL_GENL_NAME,
	.version	= ETHTOOL_GENL_VERSION,
	.netnsok	= true,
	.parallel_ops	= true,
	.ops		= ethtool_genl_ops,
	.n_ops		= ARRAY_SIZE(ethtool_genl_ops),
	.mcgrps		= ethtool_nl_mcgrps,
	.n_mcgrps	= ARRAY_SIZE(ethtool_nl_mcgrps),
};

/* module setup */

static int __init ethnl_init(void)
{
	int ret;

	ret = genl_register_family(&ethtool_genl_family);
	if (WARN(ret < 0, "ethtool: genetlink family registration failed"))
		return ret;
	ethnl_ok = true;

	ret = register_netdevice_notifier(&ethnl_netdev_notifier);
	WARN(ret < 0, "ethtool: net device notifier registration failed");
	return ret;
}

subsys_initcall(ethnl_init);