xref: /linux/net/ethtool/channels.c (revision c060f8168bdf22aa986970955af99702d142dfbe)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <net/xdp_sock_drv.h>
4 
5 #include "netlink.h"
6 #include "common.h"
7 
8 struct channels_req_info {
9 	struct ethnl_req_info		base;
10 };
11 
12 struct channels_reply_data {
13 	struct ethnl_reply_data		base;
14 	struct ethtool_channels		channels;
15 };
16 
17 #define CHANNELS_REPDATA(__reply_base) \
18 	container_of(__reply_base, struct channels_reply_data, base)
19 
20 const struct nla_policy ethnl_channels_get_policy[] = {
21 	[ETHTOOL_A_CHANNELS_HEADER]		=
22 		NLA_POLICY_NESTED(ethnl_header_policy),
23 };
24 
25 static int channels_prepare_data(const struct ethnl_req_info *req_base,
26 				 struct ethnl_reply_data *reply_base,
27 				 const struct genl_info *info)
28 {
29 	struct channels_reply_data *data = CHANNELS_REPDATA(reply_base);
30 	struct net_device *dev = reply_base->dev;
31 	int ret;
32 
33 	if (!dev->ethtool_ops->get_channels)
34 		return -EOPNOTSUPP;
35 	ret = ethnl_ops_begin(dev);
36 	if (ret < 0)
37 		return ret;
38 	dev->ethtool_ops->get_channels(dev, &data->channels);
39 	ethnl_ops_complete(dev);
40 
41 	return 0;
42 }
43 
44 static int channels_reply_size(const struct ethnl_req_info *req_base,
45 			       const struct ethnl_reply_data *reply_base)
46 {
47 	return nla_total_size(sizeof(u32)) +	/* _CHANNELS_RX_MAX */
48 	       nla_total_size(sizeof(u32)) +	/* _CHANNELS_TX_MAX */
49 	       nla_total_size(sizeof(u32)) +	/* _CHANNELS_OTHER_MAX */
50 	       nla_total_size(sizeof(u32)) +	/* _CHANNELS_COMBINED_MAX */
51 	       nla_total_size(sizeof(u32)) +	/* _CHANNELS_RX_COUNT */
52 	       nla_total_size(sizeof(u32)) +	/* _CHANNELS_TX_COUNT */
53 	       nla_total_size(sizeof(u32)) +	/* _CHANNELS_OTHER_COUNT */
54 	       nla_total_size(sizeof(u32));	/* _CHANNELS_COMBINED_COUNT */
55 }
56 
57 static int channels_fill_reply(struct sk_buff *skb,
58 			       const struct ethnl_req_info *req_base,
59 			       const struct ethnl_reply_data *reply_base)
60 {
61 	const struct channels_reply_data *data = CHANNELS_REPDATA(reply_base);
62 	const struct ethtool_channels *channels = &data->channels;
63 
64 	if ((channels->max_rx &&
65 	     (nla_put_u32(skb, ETHTOOL_A_CHANNELS_RX_MAX,
66 			  channels->max_rx) ||
67 	      nla_put_u32(skb, ETHTOOL_A_CHANNELS_RX_COUNT,
68 			  channels->rx_count))) ||
69 	    (channels->max_tx &&
70 	     (nla_put_u32(skb, ETHTOOL_A_CHANNELS_TX_MAX,
71 			  channels->max_tx) ||
72 	      nla_put_u32(skb, ETHTOOL_A_CHANNELS_TX_COUNT,
73 			  channels->tx_count))) ||
74 	    (channels->max_other &&
75 	     (nla_put_u32(skb, ETHTOOL_A_CHANNELS_OTHER_MAX,
76 			  channels->max_other) ||
77 	      nla_put_u32(skb, ETHTOOL_A_CHANNELS_OTHER_COUNT,
78 			  channels->other_count))) ||
79 	    (channels->max_combined &&
80 	     (nla_put_u32(skb, ETHTOOL_A_CHANNELS_COMBINED_MAX,
81 			  channels->max_combined) ||
82 	      nla_put_u32(skb, ETHTOOL_A_CHANNELS_COMBINED_COUNT,
83 			  channels->combined_count))))
84 		return -EMSGSIZE;
85 
86 	return 0;
87 }
88 
89 /* CHANNELS_SET */
90 
91 const struct nla_policy ethnl_channels_set_policy[] = {
92 	[ETHTOOL_A_CHANNELS_HEADER]		=
93 		NLA_POLICY_NESTED(ethnl_header_policy),
94 	[ETHTOOL_A_CHANNELS_RX_COUNT]		= { .type = NLA_U32 },
95 	[ETHTOOL_A_CHANNELS_TX_COUNT]		= { .type = NLA_U32 },
96 	[ETHTOOL_A_CHANNELS_OTHER_COUNT]	= { .type = NLA_U32 },
97 	[ETHTOOL_A_CHANNELS_COMBINED_COUNT]	= { .type = NLA_U32 },
98 };
99 
100 static int
101 ethnl_set_channels_validate(struct ethnl_req_info *req_info,
102 			    struct genl_info *info)
103 {
104 	const struct ethtool_ops *ops = req_info->dev->ethtool_ops;
105 
106 	return ops->get_channels && ops->set_channels ? 1 : -EOPNOTSUPP;
107 }
108 
109 static int
110 ethnl_set_channels(struct ethnl_req_info *req_info, struct genl_info *info)
111 {
112 	unsigned int from_channel, old_total, i;
113 	bool mod = false, mod_combined = false;
114 	struct net_device *dev = req_info->dev;
115 	struct ethtool_channels channels = {};
116 	struct nlattr **tb = info->attrs;
117 	u32 err_attr;
118 	int ret;
119 
120 	dev->ethtool_ops->get_channels(dev, &channels);
121 	old_total = channels.combined_count +
122 		    max(channels.rx_count, channels.tx_count);
123 
124 	ethnl_update_u32(&channels.rx_count, tb[ETHTOOL_A_CHANNELS_RX_COUNT],
125 			 &mod);
126 	ethnl_update_u32(&channels.tx_count, tb[ETHTOOL_A_CHANNELS_TX_COUNT],
127 			 &mod);
128 	ethnl_update_u32(&channels.other_count,
129 			 tb[ETHTOOL_A_CHANNELS_OTHER_COUNT], &mod);
130 	ethnl_update_u32(&channels.combined_count,
131 			 tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT], &mod_combined);
132 	mod |= mod_combined;
133 	if (!mod)
134 		return 0;
135 
136 	/* ensure new channel counts are within limits */
137 	if (channels.rx_count > channels.max_rx)
138 		err_attr = ETHTOOL_A_CHANNELS_RX_COUNT;
139 	else if (channels.tx_count > channels.max_tx)
140 		err_attr = ETHTOOL_A_CHANNELS_TX_COUNT;
141 	else if (channels.other_count > channels.max_other)
142 		err_attr = ETHTOOL_A_CHANNELS_OTHER_COUNT;
143 	else if (channels.combined_count > channels.max_combined)
144 		err_attr = ETHTOOL_A_CHANNELS_COMBINED_COUNT;
145 	else
146 		err_attr = 0;
147 	if (err_attr) {
148 		NL_SET_ERR_MSG_ATTR(info->extack, tb[err_attr],
149 				    "requested channel count exceeds maximum");
150 		return -EINVAL;
151 	}
152 
153 	/* ensure there is at least one RX and one TX channel */
154 	if (!channels.combined_count && !channels.rx_count)
155 		err_attr = ETHTOOL_A_CHANNELS_RX_COUNT;
156 	else if (!channels.combined_count && !channels.tx_count)
157 		err_attr = ETHTOOL_A_CHANNELS_TX_COUNT;
158 	else
159 		err_attr = 0;
160 	if (err_attr) {
161 		if (mod_combined)
162 			err_attr = ETHTOOL_A_CHANNELS_COMBINED_COUNT;
163 		NL_SET_ERR_MSG_ATTR(info->extack, tb[err_attr],
164 				    "requested channel counts would result in no RX or TX channel being configured");
165 		return -EINVAL;
166 	}
167 
168 	ret = ethtool_check_max_channel(dev, channels, info);
169 	if (ret)
170 		return ret;
171 
172 	/* Disabling channels, query zero-copy AF_XDP sockets */
173 	from_channel = channels.combined_count +
174 		       min(channels.rx_count, channels.tx_count);
175 	for (i = from_channel; i < old_total; i++)
176 		if (xsk_get_pool_from_qid(dev, i)) {
177 			GENL_SET_ERR_MSG(info, "requested channel counts are too low for existing zerocopy AF_XDP sockets");
178 			return -EINVAL;
179 		}
180 
181 	ret = dev->ethtool_ops->set_channels(dev, &channels);
182 	return ret < 0 ? ret : 1;
183 }
184 
185 const struct ethnl_request_ops ethnl_channels_request_ops = {
186 	.request_cmd		= ETHTOOL_MSG_CHANNELS_GET,
187 	.reply_cmd		= ETHTOOL_MSG_CHANNELS_GET_REPLY,
188 	.hdr_attr		= ETHTOOL_A_CHANNELS_HEADER,
189 	.req_info_size		= sizeof(struct channels_req_info),
190 	.reply_data_size	= sizeof(struct channels_reply_data),
191 
192 	.prepare_data		= channels_prepare_data,
193 	.reply_size		= channels_reply_size,
194 	.fill_reply		= channels_fill_reply,
195 
196 	.set_validate		= ethnl_set_channels_validate,
197 	.set			= ethnl_set_channels,
198 	.set_ntf_cmd		= ETHTOOL_MSG_CHANNELS_NTF,
199 };
200