xref: /linux/net/ethtool/rss.c (revision 3cf0a98fea776adb09087e521fe150c295a4b031)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include "netlink.h"
4 #include "common.h"
5 
6 struct rss_req_info {
7 	struct ethnl_req_info		base;
8 	u32				rss_context;
9 };
10 
11 struct rss_reply_data {
12 	struct ethnl_reply_data		base;
13 	bool				no_key_fields;
14 	u32				indir_size;
15 	u32				hkey_size;
16 	u32				hfunc;
17 	u32				input_xfrm;
18 	u32				*indir_table;
19 	u8				*hkey;
20 };
21 
22 #define RSS_REQINFO(__req_base) \
23 	container_of(__req_base, struct rss_req_info, base)
24 
25 #define RSS_REPDATA(__reply_base) \
26 	container_of(__reply_base, struct rss_reply_data, base)
27 
28 const struct nla_policy ethnl_rss_get_policy[] = {
29 	[ETHTOOL_A_RSS_HEADER] = NLA_POLICY_NESTED(ethnl_header_policy),
30 	[ETHTOOL_A_RSS_CONTEXT] = { .type = NLA_U32 },
31 	[ETHTOOL_A_RSS_START_CONTEXT] = { .type = NLA_U32 },
32 };
33 
34 static int
rss_parse_request(struct ethnl_req_info * req_info,struct nlattr ** tb,struct netlink_ext_ack * extack)35 rss_parse_request(struct ethnl_req_info *req_info, struct nlattr **tb,
36 		  struct netlink_ext_ack *extack)
37 {
38 	struct rss_req_info *request = RSS_REQINFO(req_info);
39 
40 	if (tb[ETHTOOL_A_RSS_CONTEXT])
41 		request->rss_context = nla_get_u32(tb[ETHTOOL_A_RSS_CONTEXT]);
42 	if (tb[ETHTOOL_A_RSS_START_CONTEXT]) {
43 		NL_SET_BAD_ATTR(extack, tb[ETHTOOL_A_RSS_START_CONTEXT]);
44 		return -EINVAL;
45 	}
46 
47 	return 0;
48 }
49 
50 static int
rss_prepare_get(const struct rss_req_info * request,struct net_device * dev,struct rss_reply_data * data,const struct genl_info * info)51 rss_prepare_get(const struct rss_req_info *request, struct net_device *dev,
52 		struct rss_reply_data *data, const struct genl_info *info)
53 {
54 	struct ethtool_rxfh_param rxfh = {};
55 	const struct ethtool_ops *ops;
56 	u32 total_size, indir_bytes;
57 	u8 *rss_config;
58 	int ret;
59 
60 	ops = dev->ethtool_ops;
61 
62 	ret = ethnl_ops_begin(dev);
63 	if (ret < 0)
64 		return ret;
65 
66 	data->indir_size = 0;
67 	data->hkey_size = 0;
68 	if (ops->get_rxfh_indir_size)
69 		data->indir_size = ops->get_rxfh_indir_size(dev);
70 	if (ops->get_rxfh_key_size)
71 		data->hkey_size = ops->get_rxfh_key_size(dev);
72 
73 	indir_bytes = data->indir_size * sizeof(u32);
74 	total_size = indir_bytes + data->hkey_size;
75 	rss_config = kzalloc(total_size, GFP_KERNEL);
76 	if (!rss_config) {
77 		ret = -ENOMEM;
78 		goto out_ops;
79 	}
80 
81 	if (data->indir_size)
82 		data->indir_table = (u32 *)rss_config;
83 	if (data->hkey_size)
84 		data->hkey = rss_config + indir_bytes;
85 
86 	rxfh.indir_size = data->indir_size;
87 	rxfh.indir = data->indir_table;
88 	rxfh.key_size = data->hkey_size;
89 	rxfh.key = data->hkey;
90 
91 	ret = ops->get_rxfh(dev, &rxfh);
92 	if (ret)
93 		goto out_ops;
94 
95 	data->hfunc = rxfh.hfunc;
96 	data->input_xfrm = rxfh.input_xfrm;
97 out_ops:
98 	ethnl_ops_complete(dev);
99 	return ret;
100 }
101 
102 static int
rss_prepare_ctx(const struct rss_req_info * request,struct net_device * dev,struct rss_reply_data * data,const struct genl_info * info)103 rss_prepare_ctx(const struct rss_req_info *request, struct net_device *dev,
104 		struct rss_reply_data *data, const struct genl_info *info)
105 {
106 	struct ethtool_rxfh_context *ctx;
107 	u32 total_size, indir_bytes;
108 	u8 *rss_config;
109 
110 	data->no_key_fields = !dev->ethtool_ops->rxfh_per_ctx_key;
111 
112 	ctx = xa_load(&dev->ethtool->rss_ctx, request->rss_context);
113 	if (!ctx)
114 		return -ENOENT;
115 
116 	data->indir_size = ctx->indir_size;
117 	data->hkey_size = ctx->key_size;
118 	data->hfunc = ctx->hfunc;
119 	data->input_xfrm = ctx->input_xfrm;
120 
121 	indir_bytes = data->indir_size * sizeof(u32);
122 	total_size = indir_bytes + data->hkey_size;
123 	rss_config = kzalloc(total_size, GFP_KERNEL);
124 	if (!rss_config)
125 		return -ENOMEM;
126 
127 	data->indir_table = (u32 *)rss_config;
128 	memcpy(data->indir_table, ethtool_rxfh_context_indir(ctx), indir_bytes);
129 
130 	if (data->hkey_size) {
131 		data->hkey = rss_config + indir_bytes;
132 		memcpy(data->hkey, ethtool_rxfh_context_key(ctx),
133 		       data->hkey_size);
134 	}
135 
136 	return 0;
137 }
138 
139 static int
rss_prepare_data(const struct ethnl_req_info * req_base,struct ethnl_reply_data * reply_base,const struct genl_info * info)140 rss_prepare_data(const struct ethnl_req_info *req_base,
141 		 struct ethnl_reply_data *reply_base,
142 		 const struct genl_info *info)
143 {
144 	struct rss_reply_data *data = RSS_REPDATA(reply_base);
145 	struct rss_req_info *request = RSS_REQINFO(req_base);
146 	struct net_device *dev = reply_base->dev;
147 	const struct ethtool_ops *ops;
148 
149 	ops = dev->ethtool_ops;
150 	if (!ops->get_rxfh)
151 		return -EOPNOTSUPP;
152 
153 	/* Some drivers don't handle rss_context */
154 	if (request->rss_context) {
155 		if (!ops->cap_rss_ctx_supported && !ops->create_rxfh_context)
156 			return -EOPNOTSUPP;
157 
158 		return rss_prepare_ctx(request, dev, data, info);
159 	}
160 
161 	return rss_prepare_get(request, dev, data, info);
162 }
163 
164 static int
rss_reply_size(const struct ethnl_req_info * req_base,const struct ethnl_reply_data * reply_base)165 rss_reply_size(const struct ethnl_req_info *req_base,
166 	       const struct ethnl_reply_data *reply_base)
167 {
168 	const struct rss_reply_data *data = RSS_REPDATA(reply_base);
169 	int len;
170 
171 	len = nla_total_size(sizeof(u32)) +	/* _RSS_CONTEXT */
172 	      nla_total_size(sizeof(u32)) +	/* _RSS_HFUNC */
173 	      nla_total_size(sizeof(u32)) +	/* _RSS_INPUT_XFRM */
174 	      nla_total_size(sizeof(u32) * data->indir_size) + /* _RSS_INDIR */
175 	      nla_total_size(data->hkey_size);	/* _RSS_HKEY */
176 
177 	return len;
178 }
179 
180 static int
rss_fill_reply(struct sk_buff * skb,const struct ethnl_req_info * req_base,const struct ethnl_reply_data * reply_base)181 rss_fill_reply(struct sk_buff *skb, const struct ethnl_req_info *req_base,
182 	       const struct ethnl_reply_data *reply_base)
183 {
184 	const struct rss_reply_data *data = RSS_REPDATA(reply_base);
185 	struct rss_req_info *request = RSS_REQINFO(req_base);
186 
187 	if (request->rss_context &&
188 	    nla_put_u32(skb, ETHTOOL_A_RSS_CONTEXT, request->rss_context))
189 		return -EMSGSIZE;
190 
191 	if ((data->indir_size &&
192 	     nla_put(skb, ETHTOOL_A_RSS_INDIR,
193 		     sizeof(u32) * data->indir_size, data->indir_table)))
194 		return -EMSGSIZE;
195 
196 	if (data->no_key_fields)
197 		return 0;
198 
199 	if ((data->hfunc &&
200 	     nla_put_u32(skb, ETHTOOL_A_RSS_HFUNC, data->hfunc)) ||
201 	    (data->input_xfrm &&
202 	     nla_put_u32(skb, ETHTOOL_A_RSS_INPUT_XFRM, data->input_xfrm)) ||
203 	    (data->hkey_size &&
204 	     nla_put(skb, ETHTOOL_A_RSS_HKEY, data->hkey_size, data->hkey)))
205 		return -EMSGSIZE;
206 
207 	return 0;
208 }
209 
rss_cleanup_data(struct ethnl_reply_data * reply_base)210 static void rss_cleanup_data(struct ethnl_reply_data *reply_base)
211 {
212 	const struct rss_reply_data *data = RSS_REPDATA(reply_base);
213 
214 	kfree(data->indir_table);
215 }
216 
217 struct rss_nl_dump_ctx {
218 	unsigned long		ifindex;
219 	unsigned long		ctx_idx;
220 
221 	/* User wants to only dump contexts from given ifindex */
222 	unsigned int		match_ifindex;
223 	unsigned int		start_ctx;
224 };
225 
rss_dump_ctx(struct netlink_callback * cb)226 static struct rss_nl_dump_ctx *rss_dump_ctx(struct netlink_callback *cb)
227 {
228 	NL_ASSERT_CTX_FITS(struct rss_nl_dump_ctx);
229 
230 	return (struct rss_nl_dump_ctx *)cb->ctx;
231 }
232 
ethnl_rss_dump_start(struct netlink_callback * cb)233 int ethnl_rss_dump_start(struct netlink_callback *cb)
234 {
235 	const struct genl_info *info = genl_info_dump(cb);
236 	struct rss_nl_dump_ctx *ctx = rss_dump_ctx(cb);
237 	struct ethnl_req_info req_info = {};
238 	struct nlattr **tb = info->attrs;
239 	int ret;
240 
241 	/* Filtering by context not supported */
242 	if (tb[ETHTOOL_A_RSS_CONTEXT]) {
243 		NL_SET_BAD_ATTR(info->extack, tb[ETHTOOL_A_RSS_CONTEXT]);
244 		return -EINVAL;
245 	}
246 	if (tb[ETHTOOL_A_RSS_START_CONTEXT]) {
247 		ctx->start_ctx = nla_get_u32(tb[ETHTOOL_A_RSS_START_CONTEXT]);
248 		ctx->ctx_idx = ctx->start_ctx;
249 	}
250 
251 	ret = ethnl_parse_header_dev_get(&req_info,
252 					 tb[ETHTOOL_A_RSS_HEADER],
253 					 sock_net(cb->skb->sk), cb->extack,
254 					 false);
255 	if (req_info.dev) {
256 		ctx->match_ifindex = req_info.dev->ifindex;
257 		ctx->ifindex = ctx->match_ifindex;
258 		ethnl_parse_header_dev_put(&req_info);
259 		req_info.dev = NULL;
260 	}
261 
262 	return ret;
263 }
264 
265 static int
rss_dump_one_ctx(struct sk_buff * skb,struct netlink_callback * cb,struct net_device * dev,u32 rss_context)266 rss_dump_one_ctx(struct sk_buff *skb, struct netlink_callback *cb,
267 		 struct net_device *dev, u32 rss_context)
268 {
269 	const struct genl_info *info = genl_info_dump(cb);
270 	struct rss_reply_data data = {};
271 	struct rss_req_info req = {};
272 	void *ehdr;
273 	int ret;
274 
275 	req.rss_context = rss_context;
276 
277 	ehdr = ethnl_dump_put(skb, cb, ETHTOOL_MSG_RSS_GET_REPLY);
278 	if (!ehdr)
279 		return -EMSGSIZE;
280 
281 	ret = ethnl_fill_reply_header(skb, dev, ETHTOOL_A_RSS_HEADER);
282 	if (ret < 0)
283 		goto err_cancel;
284 
285 	/* Context 0 is not currently storred or cached in the XArray */
286 	if (!rss_context)
287 		ret = rss_prepare_get(&req, dev, &data, info);
288 	else
289 		ret = rss_prepare_ctx(&req, dev, &data, info);
290 	if (ret)
291 		goto err_cancel;
292 
293 	ret = rss_fill_reply(skb, &req.base, &data.base);
294 	if (ret)
295 		goto err_cleanup;
296 	genlmsg_end(skb, ehdr);
297 
298 	rss_cleanup_data(&data.base);
299 	return 0;
300 
301 err_cleanup:
302 	rss_cleanup_data(&data.base);
303 err_cancel:
304 	genlmsg_cancel(skb, ehdr);
305 	return ret;
306 }
307 
308 static int
rss_dump_one_dev(struct sk_buff * skb,struct netlink_callback * cb,struct net_device * dev)309 rss_dump_one_dev(struct sk_buff *skb, struct netlink_callback *cb,
310 		 struct net_device *dev)
311 {
312 	struct rss_nl_dump_ctx *ctx = rss_dump_ctx(cb);
313 	int ret;
314 
315 	if (!dev->ethtool_ops->get_rxfh)
316 		return 0;
317 
318 	if (!ctx->ctx_idx) {
319 		ret = rss_dump_one_ctx(skb, cb, dev, 0);
320 		if (ret)
321 			return ret;
322 		ctx->ctx_idx++;
323 	}
324 
325 	for (; xa_find(&dev->ethtool->rss_ctx, &ctx->ctx_idx,
326 		       ULONG_MAX, XA_PRESENT); ctx->ctx_idx++) {
327 		ret = rss_dump_one_ctx(skb, cb, dev, ctx->ctx_idx);
328 		if (ret)
329 			return ret;
330 	}
331 	ctx->ctx_idx = ctx->start_ctx;
332 
333 	return 0;
334 }
335 
ethnl_rss_dumpit(struct sk_buff * skb,struct netlink_callback * cb)336 int ethnl_rss_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
337 {
338 	struct rss_nl_dump_ctx *ctx = rss_dump_ctx(cb);
339 	struct net *net = sock_net(skb->sk);
340 	struct net_device *dev;
341 	int ret = 0;
342 
343 	rtnl_lock();
344 	for_each_netdev_dump(net, dev, ctx->ifindex) {
345 		if (ctx->match_ifindex && ctx->match_ifindex != ctx->ifindex)
346 			break;
347 
348 		ret = rss_dump_one_dev(skb, cb, dev);
349 		if (ret)
350 			break;
351 	}
352 	rtnl_unlock();
353 
354 	return ret;
355 }
356 
357 const struct ethnl_request_ops ethnl_rss_request_ops = {
358 	.request_cmd		= ETHTOOL_MSG_RSS_GET,
359 	.reply_cmd		= ETHTOOL_MSG_RSS_GET_REPLY,
360 	.hdr_attr		= ETHTOOL_A_RSS_HEADER,
361 	.req_info_size		= sizeof(struct rss_req_info),
362 	.reply_data_size	= sizeof(struct rss_reply_data),
363 
364 	.parse_request		= rss_parse_request,
365 	.prepare_data		= rss_prepare_data,
366 	.reply_size		= rss_reply_size,
367 	.fill_reply		= rss_fill_reply,
368 	.cleanup_data		= rss_cleanup_data,
369 };
370