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
8struct channels_req_info {
9	struct ethnl_req_info		base;
10};
11
12struct 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
20const struct nla_policy ethnl_channels_get_policy[] = {
21	[ETHTOOL_A_CHANNELS_HEADER]		=
22		NLA_POLICY_NESTED(ethnl_header_policy),
23};
24
25static 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
44static 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
57static 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
91const 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
100static int
101ethnl_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
109static int
110ethnl_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, max_rxfh_in_use;
118	u64 max_rxnfc_in_use;
119	int ret;
120
121	dev->ethtool_ops->get_channels(dev, &channels);
122	old_total = channels.combined_count +
123		    max(channels.rx_count, channels.tx_count);
124
125	ethnl_update_u32(&channels.rx_count, tb[ETHTOOL_A_CHANNELS_RX_COUNT],
126			 &mod);
127	ethnl_update_u32(&channels.tx_count, tb[ETHTOOL_A_CHANNELS_TX_COUNT],
128			 &mod);
129	ethnl_update_u32(&channels.other_count,
130			 tb[ETHTOOL_A_CHANNELS_OTHER_COUNT], &mod);
131	ethnl_update_u32(&channels.combined_count,
132			 tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT], &mod_combined);
133	mod |= mod_combined;
134	if (!mod)
135		return 0;
136
137	/* ensure new channel counts are within limits */
138	if (channels.rx_count > channels.max_rx)
139		err_attr = ETHTOOL_A_CHANNELS_RX_COUNT;
140	else if (channels.tx_count > channels.max_tx)
141		err_attr = ETHTOOL_A_CHANNELS_TX_COUNT;
142	else if (channels.other_count > channels.max_other)
143		err_attr = ETHTOOL_A_CHANNELS_OTHER_COUNT;
144	else if (channels.combined_count > channels.max_combined)
145		err_attr = ETHTOOL_A_CHANNELS_COMBINED_COUNT;
146	else
147		err_attr = 0;
148	if (err_attr) {
149		NL_SET_ERR_MSG_ATTR(info->extack, tb[err_attr],
150				    "requested channel count exceeds maximum");
151		return -EINVAL;
152	}
153
154	/* ensure there is at least one RX and one TX channel */
155	if (!channels.combined_count && !channels.rx_count)
156		err_attr = ETHTOOL_A_CHANNELS_RX_COUNT;
157	else if (!channels.combined_count && !channels.tx_count)
158		err_attr = ETHTOOL_A_CHANNELS_TX_COUNT;
159	else
160		err_attr = 0;
161	if (err_attr) {
162		if (mod_combined)
163			err_attr = ETHTOOL_A_CHANNELS_COMBINED_COUNT;
164		NL_SET_ERR_MSG_ATTR(info->extack, tb[err_attr],
165				    "requested channel counts would result in no RX or TX channel being configured");
166		return -EINVAL;
167	}
168
169	/* ensure the new Rx count fits within the configured Rx flow
170	 * indirection table/rxnfc settings
171	 */
172	if (ethtool_get_max_rxnfc_channel(dev, &max_rxnfc_in_use))
173		max_rxnfc_in_use = 0;
174	if (!netif_is_rxfh_configured(dev) ||
175	    ethtool_get_max_rxfh_channel(dev, &max_rxfh_in_use))
176		max_rxfh_in_use = 0;
177	if (channels.combined_count + channels.rx_count <= max_rxfh_in_use) {
178		GENL_SET_ERR_MSG(info, "requested channel counts are too low for existing indirection table settings");
179		return -EINVAL;
180	}
181	if (channels.combined_count + channels.rx_count <= max_rxnfc_in_use) {
182		GENL_SET_ERR_MSG(info, "requested channel counts are too low for existing ntuple filter settings");
183		return -EINVAL;
184	}
185
186	/* Disabling channels, query zero-copy AF_XDP sockets */
187	from_channel = channels.combined_count +
188		       min(channels.rx_count, channels.tx_count);
189	for (i = from_channel; i < old_total; i++)
190		if (xsk_get_pool_from_qid(dev, i)) {
191			GENL_SET_ERR_MSG(info, "requested channel counts are too low for existing zerocopy AF_XDP sockets");
192			return -EINVAL;
193		}
194
195	ret = dev->ethtool_ops->set_channels(dev, &channels);
196	return ret < 0 ? ret : 1;
197}
198
199const struct ethnl_request_ops ethnl_channels_request_ops = {
200	.request_cmd		= ETHTOOL_MSG_CHANNELS_GET,
201	.reply_cmd		= ETHTOOL_MSG_CHANNELS_GET_REPLY,
202	.hdr_attr		= ETHTOOL_A_CHANNELS_HEADER,
203	.req_info_size		= sizeof(struct channels_req_info),
204	.reply_data_size	= sizeof(struct channels_reply_data),
205
206	.prepare_data		= channels_prepare_data,
207	.reply_size		= channels_reply_size,
208	.fill_reply		= channels_fill_reply,
209
210	.set_validate		= ethnl_set_channels_validate,
211	.set			= ethnl_set_channels,
212	.set_ntf_cmd		= ETHTOOL_MSG_CHANNELS_NTF,
213};
214