xref: /linux/net/ethtool/features.c (revision cf21f328fcafacf4f96e7a30ef9dceede1076378)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include "netlink.h"
4 #include "common.h"
5 #include "bitset.h"
6 
7 struct features_req_info {
8 	struct ethnl_req_info	base;
9 };
10 
11 struct features_reply_data {
12 	struct ethnl_reply_data	base;
13 	u32			hw[ETHTOOL_DEV_FEATURE_WORDS];
14 	u32			wanted[ETHTOOL_DEV_FEATURE_WORDS];
15 	u32			active[ETHTOOL_DEV_FEATURE_WORDS];
16 	u32			nochange[ETHTOOL_DEV_FEATURE_WORDS];
17 	u32			all[ETHTOOL_DEV_FEATURE_WORDS];
18 };
19 
20 #define FEATURES_REPDATA(__reply_base) \
21 	container_of(__reply_base, struct features_reply_data, base)
22 
23 const struct nla_policy ethnl_features_get_policy[] = {
24 	[ETHTOOL_A_FEATURES_HEADER]	=
25 		NLA_POLICY_NESTED(ethnl_header_policy),
26 };
27 
28 static void ethnl_features_to_bitmap32(u32 *dest, netdev_features_t src)
29 {
30 	unsigned int i;
31 
32 	for (i = 0; i < ETHTOOL_DEV_FEATURE_WORDS; i++)
33 		dest[i] = src >> (32 * i);
34 }
35 
36 static int features_prepare_data(const struct ethnl_req_info *req_base,
37 				 struct ethnl_reply_data *reply_base,
38 				 struct genl_info *info)
39 {
40 	struct features_reply_data *data = FEATURES_REPDATA(reply_base);
41 	struct net_device *dev = reply_base->dev;
42 	netdev_features_t all_features;
43 
44 	ethnl_features_to_bitmap32(data->hw, dev->hw_features);
45 	ethnl_features_to_bitmap32(data->wanted, dev->wanted_features);
46 	ethnl_features_to_bitmap32(data->active, dev->features);
47 	ethnl_features_to_bitmap32(data->nochange, NETIF_F_NEVER_CHANGE);
48 	all_features = GENMASK_ULL(NETDEV_FEATURE_COUNT - 1, 0);
49 	ethnl_features_to_bitmap32(data->all, all_features);
50 
51 	return 0;
52 }
53 
54 static int features_reply_size(const struct ethnl_req_info *req_base,
55 			       const struct ethnl_reply_data *reply_base)
56 {
57 	const struct features_reply_data *data = FEATURES_REPDATA(reply_base);
58 	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
59 	unsigned int len = 0;
60 	int ret;
61 
62 	ret = ethnl_bitset32_size(data->hw, data->all, NETDEV_FEATURE_COUNT,
63 				  netdev_features_strings, compact);
64 	if (ret < 0)
65 		return ret;
66 	len += ret;
67 	ret = ethnl_bitset32_size(data->wanted, NULL, NETDEV_FEATURE_COUNT,
68 				  netdev_features_strings, compact);
69 	if (ret < 0)
70 		return ret;
71 	len += ret;
72 	ret = ethnl_bitset32_size(data->active, NULL, NETDEV_FEATURE_COUNT,
73 				  netdev_features_strings, compact);
74 	if (ret < 0)
75 		return ret;
76 	len += ret;
77 	ret = ethnl_bitset32_size(data->nochange, NULL, NETDEV_FEATURE_COUNT,
78 				  netdev_features_strings, compact);
79 	if (ret < 0)
80 		return ret;
81 	len += ret;
82 
83 	return len;
84 }
85 
86 static int features_fill_reply(struct sk_buff *skb,
87 			       const struct ethnl_req_info *req_base,
88 			       const struct ethnl_reply_data *reply_base)
89 {
90 	const struct features_reply_data *data = FEATURES_REPDATA(reply_base);
91 	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
92 	int ret;
93 
94 	ret = ethnl_put_bitset32(skb, ETHTOOL_A_FEATURES_HW, data->hw,
95 				 data->all, NETDEV_FEATURE_COUNT,
96 				 netdev_features_strings, compact);
97 	if (ret < 0)
98 		return ret;
99 	ret = ethnl_put_bitset32(skb, ETHTOOL_A_FEATURES_WANTED, data->wanted,
100 				 NULL, NETDEV_FEATURE_COUNT,
101 				 netdev_features_strings, compact);
102 	if (ret < 0)
103 		return ret;
104 	ret = ethnl_put_bitset32(skb, ETHTOOL_A_FEATURES_ACTIVE, data->active,
105 				 NULL, NETDEV_FEATURE_COUNT,
106 				 netdev_features_strings, compact);
107 	if (ret < 0)
108 		return ret;
109 	return ethnl_put_bitset32(skb, ETHTOOL_A_FEATURES_NOCHANGE,
110 				  data->nochange, NULL, NETDEV_FEATURE_COUNT,
111 				  netdev_features_strings, compact);
112 }
113 
114 const struct ethnl_request_ops ethnl_features_request_ops = {
115 	.request_cmd		= ETHTOOL_MSG_FEATURES_GET,
116 	.reply_cmd		= ETHTOOL_MSG_FEATURES_GET_REPLY,
117 	.hdr_attr		= ETHTOOL_A_FEATURES_HEADER,
118 	.req_info_size		= sizeof(struct features_req_info),
119 	.reply_data_size	= sizeof(struct features_reply_data),
120 
121 	.prepare_data		= features_prepare_data,
122 	.reply_size		= features_reply_size,
123 	.fill_reply		= features_fill_reply,
124 };
125 
126 /* FEATURES_SET */
127 
128 const struct nla_policy ethnl_features_set_policy[] = {
129 	[ETHTOOL_A_FEATURES_HEADER]	=
130 		NLA_POLICY_NESTED(ethnl_header_policy),
131 	[ETHTOOL_A_FEATURES_WANTED]	= { .type = NLA_NESTED },
132 };
133 
134 static void ethnl_features_to_bitmap(unsigned long *dest, netdev_features_t val)
135 {
136 	const unsigned int words = BITS_TO_LONGS(NETDEV_FEATURE_COUNT);
137 	unsigned int i;
138 
139 	for (i = 0; i < words; i++)
140 		dest[i] = (unsigned long)(val >> (i * BITS_PER_LONG));
141 }
142 
143 static netdev_features_t ethnl_bitmap_to_features(unsigned long *src)
144 {
145 	const unsigned int nft_bits = sizeof(netdev_features_t) * BITS_PER_BYTE;
146 	const unsigned int words = BITS_TO_LONGS(NETDEV_FEATURE_COUNT);
147 	netdev_features_t ret = 0;
148 	unsigned int i;
149 
150 	for (i = 0; i < words; i++)
151 		ret |= (netdev_features_t)(src[i]) << (i * BITS_PER_LONG);
152 	ret &= ~(netdev_features_t)0 >> (nft_bits - NETDEV_FEATURE_COUNT);
153 	return ret;
154 }
155 
156 static int features_send_reply(struct net_device *dev, struct genl_info *info,
157 			       const unsigned long *wanted,
158 			       const unsigned long *wanted_mask,
159 			       const unsigned long *active,
160 			       const unsigned long *active_mask, bool compact)
161 {
162 	struct sk_buff *rskb;
163 	void *reply_payload;
164 	int reply_len = 0;
165 	int ret;
166 
167 	reply_len = ethnl_reply_header_size();
168 	ret = ethnl_bitset_size(wanted, wanted_mask, NETDEV_FEATURE_COUNT,
169 				netdev_features_strings, compact);
170 	if (ret < 0)
171 		goto err;
172 	reply_len += ret;
173 	ret = ethnl_bitset_size(active, active_mask, NETDEV_FEATURE_COUNT,
174 				netdev_features_strings, compact);
175 	if (ret < 0)
176 		goto err;
177 	reply_len += ret;
178 
179 	ret = -ENOMEM;
180 	rskb = ethnl_reply_init(reply_len, dev, ETHTOOL_MSG_FEATURES_SET_REPLY,
181 				ETHTOOL_A_FEATURES_HEADER, info,
182 				&reply_payload);
183 	if (!rskb)
184 		goto err;
185 
186 	ret = ethnl_put_bitset(rskb, ETHTOOL_A_FEATURES_WANTED, wanted,
187 			       wanted_mask, NETDEV_FEATURE_COUNT,
188 			       netdev_features_strings, compact);
189 	if (ret < 0)
190 		goto nla_put_failure;
191 	ret = ethnl_put_bitset(rskb, ETHTOOL_A_FEATURES_ACTIVE, active,
192 			       active_mask, NETDEV_FEATURE_COUNT,
193 			       netdev_features_strings, compact);
194 	if (ret < 0)
195 		goto nla_put_failure;
196 
197 	genlmsg_end(rskb, reply_payload);
198 	ret = genlmsg_reply(rskb, info);
199 	return ret;
200 
201 nla_put_failure:
202 	nlmsg_free(rskb);
203 	WARN_ONCE(1, "calculated message payload length (%d) not sufficient\n",
204 		  reply_len);
205 err:
206 	GENL_SET_ERR_MSG(info, "failed to send reply message");
207 	return ret;
208 }
209 
210 int ethnl_set_features(struct sk_buff *skb, struct genl_info *info)
211 {
212 	DECLARE_BITMAP(wanted_diff_mask, NETDEV_FEATURE_COUNT);
213 	DECLARE_BITMAP(active_diff_mask, NETDEV_FEATURE_COUNT);
214 	DECLARE_BITMAP(old_active, NETDEV_FEATURE_COUNT);
215 	DECLARE_BITMAP(old_wanted, NETDEV_FEATURE_COUNT);
216 	DECLARE_BITMAP(new_active, NETDEV_FEATURE_COUNT);
217 	DECLARE_BITMAP(new_wanted, NETDEV_FEATURE_COUNT);
218 	DECLARE_BITMAP(req_wanted, NETDEV_FEATURE_COUNT);
219 	DECLARE_BITMAP(req_mask, NETDEV_FEATURE_COUNT);
220 	struct ethnl_req_info req_info = {};
221 	struct nlattr **tb = info->attrs;
222 	struct net_device *dev;
223 	bool mod;
224 	int ret;
225 
226 	if (!tb[ETHTOOL_A_FEATURES_WANTED])
227 		return -EINVAL;
228 	ret = ethnl_parse_header_dev_get(&req_info,
229 					 tb[ETHTOOL_A_FEATURES_HEADER],
230 					 genl_info_net(info), info->extack,
231 					 true);
232 	if (ret < 0)
233 		return ret;
234 	dev = req_info.dev;
235 
236 	rtnl_lock();
237 	ethnl_features_to_bitmap(old_active, dev->features);
238 	ethnl_features_to_bitmap(old_wanted, dev->wanted_features);
239 	ret = ethnl_parse_bitset(req_wanted, req_mask, NETDEV_FEATURE_COUNT,
240 				 tb[ETHTOOL_A_FEATURES_WANTED],
241 				 netdev_features_strings, info->extack);
242 	if (ret < 0)
243 		goto out_rtnl;
244 	if (ethnl_bitmap_to_features(req_mask) & ~NETIF_F_ETHTOOL_BITS) {
245 		GENL_SET_ERR_MSG(info, "attempt to change non-ethtool features");
246 		ret = -EINVAL;
247 		goto out_rtnl;
248 	}
249 
250 	/* set req_wanted bits not in req_mask from old_wanted */
251 	bitmap_and(req_wanted, req_wanted, req_mask, NETDEV_FEATURE_COUNT);
252 	bitmap_andnot(new_wanted, old_wanted, req_mask, NETDEV_FEATURE_COUNT);
253 	bitmap_or(req_wanted, new_wanted, req_wanted, NETDEV_FEATURE_COUNT);
254 	if (!bitmap_equal(req_wanted, old_wanted, NETDEV_FEATURE_COUNT)) {
255 		dev->wanted_features &= ~dev->hw_features;
256 		dev->wanted_features |= ethnl_bitmap_to_features(req_wanted) & dev->hw_features;
257 		__netdev_update_features(dev);
258 	}
259 	ethnl_features_to_bitmap(new_active, dev->features);
260 	mod = !bitmap_equal(old_active, new_active, NETDEV_FEATURE_COUNT);
261 
262 	ret = 0;
263 	if (!(req_info.flags & ETHTOOL_FLAG_OMIT_REPLY)) {
264 		bool compact = req_info.flags & ETHTOOL_FLAG_COMPACT_BITSETS;
265 
266 		bitmap_xor(wanted_diff_mask, req_wanted, new_active,
267 			   NETDEV_FEATURE_COUNT);
268 		bitmap_xor(active_diff_mask, old_active, new_active,
269 			   NETDEV_FEATURE_COUNT);
270 		bitmap_and(wanted_diff_mask, wanted_diff_mask, req_mask,
271 			   NETDEV_FEATURE_COUNT);
272 		bitmap_and(req_wanted, req_wanted, wanted_diff_mask,
273 			   NETDEV_FEATURE_COUNT);
274 		bitmap_and(new_active, new_active, active_diff_mask,
275 			   NETDEV_FEATURE_COUNT);
276 
277 		ret = features_send_reply(dev, info, req_wanted,
278 					  wanted_diff_mask, new_active,
279 					  active_diff_mask, compact);
280 	}
281 	if (mod)
282 		netdev_features_change(dev);
283 
284 out_rtnl:
285 	rtnl_unlock();
286 	ethnl_parse_header_dev_put(&req_info);
287 	return ret;
288 }
289