1// SPDX-License-Identifier: GPL-2.0-only
2
3#include "netlink.h"
4#include "common.h"
5
6struct rss_req_info {
7 struct ethnl_req_info base;
8 u32 rss_context;
9};
10
11struct rss_reply_data {
12 struct ethnl_reply_data base;
13 u32 indir_size;
14 u32 hkey_size;
15 u32 hfunc;
16 u32 input_xfrm;
17 u32 *indir_table;
18 u8 *hkey;
19};
20
21#define RSS_REQINFO(__req_base) \
22 container_of(__req_base, struct rss_req_info, base)
23
24#define RSS_REPDATA(__reply_base) \
25 container_of(__reply_base, struct rss_reply_data, base)
26
27const struct nla_policy ethnl_rss_get_policy[] = {
28 [ETHTOOL_A_RSS_HEADER] = NLA_POLICY_NESTED(ethnl_header_policy),
29 [ETHTOOL_A_RSS_CONTEXT] = { .type = NLA_U32 },
30};
31
32static int
33rss_parse_request(struct ethnl_req_info *req_info, struct nlattr **tb,
34 struct netlink_ext_ack *extack)
35{
36 struct rss_req_info *request = RSS_REQINFO(req_info);
37
38 if (tb[ETHTOOL_A_RSS_CONTEXT])
39 request->rss_context = nla_get_u32(nla: tb[ETHTOOL_A_RSS_CONTEXT]);
40
41 return 0;
42}
43
44static int
45rss_prepare_data(const struct ethnl_req_info *req_base,
46 struct ethnl_reply_data *reply_base,
47 const struct genl_info *info)
48{
49 struct rss_reply_data *data = RSS_REPDATA(reply_base);
50 struct rss_req_info *request = RSS_REQINFO(req_base);
51 struct net_device *dev = reply_base->dev;
52 struct ethtool_rxfh_param rxfh = {};
53 const struct ethtool_ops *ops;
54 u32 total_size, indir_bytes;
55 u8 *rss_config;
56 int ret;
57
58 ops = dev->ethtool_ops;
59 if (!ops->get_rxfh)
60 return -EOPNOTSUPP;
61
62 /* Some drivers don't handle rss_context */
63 if (request->rss_context && !ops->cap_rss_ctx_supported)
64 return -EOPNOTSUPP;
65
66 ret = ethnl_ops_begin(dev);
67 if (ret < 0)
68 return ret;
69
70 data->indir_size = 0;
71 data->hkey_size = 0;
72 if (ops->get_rxfh_indir_size)
73 data->indir_size = ops->get_rxfh_indir_size(dev);
74 if (ops->get_rxfh_key_size)
75 data->hkey_size = ops->get_rxfh_key_size(dev);
76
77 indir_bytes = data->indir_size * sizeof(u32);
78 total_size = indir_bytes + data->hkey_size;
79 rss_config = kzalloc(size: total_size, GFP_KERNEL);
80 if (!rss_config) {
81 ret = -ENOMEM;
82 goto out_ops;
83 }
84
85 if (data->indir_size)
86 data->indir_table = (u32 *)rss_config;
87 if (data->hkey_size)
88 data->hkey = rss_config + indir_bytes;
89
90 rxfh.indir_size = data->indir_size;
91 rxfh.indir = data->indir_table;
92 rxfh.key_size = data->hkey_size;
93 rxfh.key = data->hkey;
94 rxfh.rss_context = request->rss_context;
95
96 ret = ops->get_rxfh(dev, &rxfh);
97 if (ret)
98 goto out_ops;
99
100 data->hfunc = rxfh.hfunc;
101 data->input_xfrm = rxfh.input_xfrm;
102out_ops:
103 ethnl_ops_complete(dev);
104 return ret;
105}
106
107static int
108rss_reply_size(const struct ethnl_req_info *req_base,
109 const struct ethnl_reply_data *reply_base)
110{
111 const struct rss_reply_data *data = RSS_REPDATA(reply_base);
112 int len;
113
114 len = nla_total_size(payload: sizeof(u32)) + /* _RSS_HFUNC */
115 nla_total_size(payload: sizeof(u32)) + /* _RSS_INPUT_XFRM */
116 nla_total_size(payload: sizeof(u32) * data->indir_size) + /* _RSS_INDIR */
117 nla_total_size(payload: data->hkey_size); /* _RSS_HKEY */
118
119 return len;
120}
121
122static int
123rss_fill_reply(struct sk_buff *skb, const struct ethnl_req_info *req_base,
124 const struct ethnl_reply_data *reply_base)
125{
126 const struct rss_reply_data *data = RSS_REPDATA(reply_base);
127
128 if ((data->hfunc &&
129 nla_put_u32(skb, attrtype: ETHTOOL_A_RSS_HFUNC, value: data->hfunc)) ||
130 (data->input_xfrm &&
131 nla_put_u32(skb, attrtype: ETHTOOL_A_RSS_INPUT_XFRM, value: data->input_xfrm)) ||
132 (data->indir_size &&
133 nla_put(skb, attrtype: ETHTOOL_A_RSS_INDIR,
134 attrlen: sizeof(u32) * data->indir_size, data: data->indir_table)) ||
135 (data->hkey_size &&
136 nla_put(skb, attrtype: ETHTOOL_A_RSS_HKEY, attrlen: data->hkey_size, data: data->hkey)))
137 return -EMSGSIZE;
138
139 return 0;
140}
141
142static void rss_cleanup_data(struct ethnl_reply_data *reply_base)
143{
144 const struct rss_reply_data *data = RSS_REPDATA(reply_base);
145
146 kfree(objp: data->indir_table);
147}
148
149const struct ethnl_request_ops ethnl_rss_request_ops = {
150 .request_cmd = ETHTOOL_MSG_RSS_GET,
151 .reply_cmd = ETHTOOL_MSG_RSS_GET_REPLY,
152 .hdr_attr = ETHTOOL_A_RSS_HEADER,
153 .req_info_size = sizeof(struct rss_req_info),
154 .reply_data_size = sizeof(struct rss_reply_data),
155
156 .parse_request = rss_parse_request,
157 .prepare_data = rss_prepare_data,
158 .reply_size = rss_reply_size,
159 .fill_reply = rss_fill_reply,
160 .cleanup_data = rss_cleanup_data,
161};
162

source code of linux/net/ethtool/rss.c