xref: /linux/net/ethtool/privflags.c (revision 23c48a124b469cee2eb0c75e6d22d366d1caa118)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include "netlink.h"
4 #include "common.h"
5 #include "bitset.h"
6 
7 struct privflags_req_info {
8 	struct ethnl_req_info		base;
9 };
10 
11 struct privflags_reply_data {
12 	struct ethnl_reply_data		base;
13 	const char			(*priv_flag_names)[ETH_GSTRING_LEN];
14 	unsigned int			n_priv_flags;
15 	u32				priv_flags;
16 };
17 
18 #define PRIVFLAGS_REPDATA(__reply_base) \
19 	container_of(__reply_base, struct privflags_reply_data, base)
20 
21 const struct nla_policy ethnl_privflags_get_policy[] = {
22 	[ETHTOOL_A_PRIVFLAGS_HEADER]		=
23 		NLA_POLICY_NESTED(ethnl_header_policy),
24 };
25 
26 static int ethnl_get_priv_flags_info(struct net_device *dev,
27 				     unsigned int *count,
28 				     const char (**names)[ETH_GSTRING_LEN])
29 {
30 	const struct ethtool_ops *ops = dev->ethtool_ops;
31 	int nflags;
32 
33 	nflags = ops->get_sset_count(dev, ETH_SS_PRIV_FLAGS);
34 	if (nflags < 0)
35 		return nflags;
36 
37 	if (names) {
38 		*names = kcalloc(nflags, ETH_GSTRING_LEN, GFP_KERNEL);
39 		if (!*names)
40 			return -ENOMEM;
41 		ops->get_strings(dev, ETH_SS_PRIV_FLAGS, (u8 *)*names);
42 	}
43 
44 	/* We can pass more than 32 private flags to userspace via netlink but
45 	 * we cannot get more with ethtool_ops::get_priv_flags(). Note that we
46 	 * must not adjust nflags before allocating the space for flag names
47 	 * as the buffer must be large enough for all flags.
48 	 */
49 	if (WARN_ONCE(nflags > 32,
50 		      "device %s reports more than 32 private flags (%d)\n",
51 		      netdev_name(dev), nflags))
52 		nflags = 32;
53 	*count = nflags;
54 
55 	return 0;
56 }
57 
58 static int privflags_prepare_data(const struct ethnl_req_info *req_base,
59 				  struct ethnl_reply_data *reply_base,
60 				  struct genl_info *info)
61 {
62 	struct privflags_reply_data *data = PRIVFLAGS_REPDATA(reply_base);
63 	struct net_device *dev = reply_base->dev;
64 	const char (*names)[ETH_GSTRING_LEN];
65 	const struct ethtool_ops *ops;
66 	unsigned int nflags;
67 	int ret;
68 
69 	ops = dev->ethtool_ops;
70 	if (!ops->get_priv_flags || !ops->get_sset_count || !ops->get_strings)
71 		return -EOPNOTSUPP;
72 	ret = ethnl_ops_begin(dev);
73 	if (ret < 0)
74 		return ret;
75 
76 	ret = ethnl_get_priv_flags_info(dev, &nflags, &names);
77 	if (ret < 0)
78 		goto out_ops;
79 	data->priv_flags = ops->get_priv_flags(dev);
80 	data->priv_flag_names = names;
81 	data->n_priv_flags = nflags;
82 
83 out_ops:
84 	ethnl_ops_complete(dev);
85 	return ret;
86 }
87 
88 static int privflags_reply_size(const struct ethnl_req_info *req_base,
89 				const struct ethnl_reply_data *reply_base)
90 {
91 	const struct privflags_reply_data *data = PRIVFLAGS_REPDATA(reply_base);
92 	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
93 	const u32 all_flags = ~(u32)0 >> (32 - data->n_priv_flags);
94 
95 	return ethnl_bitset32_size(&data->priv_flags, &all_flags,
96 				   data->n_priv_flags,
97 				   data->priv_flag_names, compact);
98 }
99 
100 static int privflags_fill_reply(struct sk_buff *skb,
101 				const struct ethnl_req_info *req_base,
102 				const struct ethnl_reply_data *reply_base)
103 {
104 	const struct privflags_reply_data *data = PRIVFLAGS_REPDATA(reply_base);
105 	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
106 	const u32 all_flags = ~(u32)0 >> (32 - data->n_priv_flags);
107 
108 	return ethnl_put_bitset32(skb, ETHTOOL_A_PRIVFLAGS_FLAGS,
109 				  &data->priv_flags, &all_flags,
110 				  data->n_priv_flags, data->priv_flag_names,
111 				  compact);
112 }
113 
114 static void privflags_cleanup_data(struct ethnl_reply_data *reply_data)
115 {
116 	struct privflags_reply_data *data = PRIVFLAGS_REPDATA(reply_data);
117 
118 	kfree(data->priv_flag_names);
119 }
120 
121 const struct ethnl_request_ops ethnl_privflags_request_ops = {
122 	.request_cmd		= ETHTOOL_MSG_PRIVFLAGS_GET,
123 	.reply_cmd		= ETHTOOL_MSG_PRIVFLAGS_GET_REPLY,
124 	.hdr_attr		= ETHTOOL_A_PRIVFLAGS_HEADER,
125 	.req_info_size		= sizeof(struct privflags_req_info),
126 	.reply_data_size	= sizeof(struct privflags_reply_data),
127 
128 	.prepare_data		= privflags_prepare_data,
129 	.reply_size		= privflags_reply_size,
130 	.fill_reply		= privflags_fill_reply,
131 	.cleanup_data		= privflags_cleanup_data,
132 };
133 
134 /* PRIVFLAGS_SET */
135 
136 const struct nla_policy ethnl_privflags_set_policy[] = {
137 	[ETHTOOL_A_PRIVFLAGS_HEADER]		=
138 		NLA_POLICY_NESTED(ethnl_header_policy),
139 	[ETHTOOL_A_PRIVFLAGS_FLAGS]		= { .type = NLA_NESTED },
140 };
141 
142 int ethnl_set_privflags(struct sk_buff *skb, struct genl_info *info)
143 {
144 	const char (*names)[ETH_GSTRING_LEN] = NULL;
145 	struct ethnl_req_info req_info = {};
146 	struct nlattr **tb = info->attrs;
147 	const struct ethtool_ops *ops;
148 	struct net_device *dev;
149 	unsigned int nflags;
150 	bool mod = false;
151 	bool compact;
152 	u32 flags;
153 	int ret;
154 
155 	if (!tb[ETHTOOL_A_PRIVFLAGS_FLAGS])
156 		return -EINVAL;
157 	ret = ethnl_bitset_is_compact(tb[ETHTOOL_A_PRIVFLAGS_FLAGS], &compact);
158 	if (ret < 0)
159 		return ret;
160 	ret = ethnl_parse_header_dev_get(&req_info,
161 					 tb[ETHTOOL_A_PRIVFLAGS_HEADER],
162 					 genl_info_net(info), info->extack,
163 					 true);
164 	if (ret < 0)
165 		return ret;
166 	dev = req_info.dev;
167 	ops = dev->ethtool_ops;
168 	ret = -EOPNOTSUPP;
169 	if (!ops->get_priv_flags || !ops->set_priv_flags ||
170 	    !ops->get_sset_count || !ops->get_strings)
171 		goto out_dev;
172 
173 	rtnl_lock();
174 	ret = ethnl_ops_begin(dev);
175 	if (ret < 0)
176 		goto out_rtnl;
177 	ret = ethnl_get_priv_flags_info(dev, &nflags, compact ? NULL : &names);
178 	if (ret < 0)
179 		goto out_ops;
180 	flags = ops->get_priv_flags(dev);
181 
182 	ret = ethnl_update_bitset32(&flags, nflags,
183 				    tb[ETHTOOL_A_PRIVFLAGS_FLAGS], names,
184 				    info->extack, &mod);
185 	if (ret < 0 || !mod)
186 		goto out_free;
187 	ret = ops->set_priv_flags(dev, flags);
188 	if (ret < 0)
189 		goto out_free;
190 	ethtool_notify(dev, ETHTOOL_MSG_PRIVFLAGS_NTF, NULL);
191 
192 out_free:
193 	kfree(names);
194 out_ops:
195 	ethnl_ops_complete(dev);
196 out_rtnl:
197 	rtnl_unlock();
198 out_dev:
199 	ethnl_parse_header_dev_put(&req_info);
200 	return ret;
201 }
202