1 /*
2  * Copyright (C) 2017 Netronome Systems, Inc.
3  *
4  * This software is dual licensed under the GNU General License Version 2,
5  * June 1991 as shown in the file COPYING in the top-level directory of this
6  * source tree or the BSD 2-Clause License provided below.  You have the
7  * option to license this software under the complete terms of either license.
8  *
9  * The BSD 2-Clause License:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      1. Redistributions of source code must retain the above
16  *         copyright notice, this list of conditions and the following
17  *         disclaimer.
18  *
19  *      2. Redistributions in binary form must reproduce the above
20  *         copyright notice, this list of conditions and the following
21  *         disclaimer in the documentation and/or other materials
22  *         provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 #include <linux/skbuff.h>
35 #include <net/devlink.h>
36 #include <net/pkt_cls.h>
37 
38 #include "cmsg.h"
39 #include "main.h"
40 #include "../nfpcore/nfp_cpp.h"
41 #include "../nfpcore/nfp_nsp.h"
42 #include "../nfp_app.h"
43 #include "../nfp_main.h"
44 #include "../nfp_net.h"
45 #include "../nfp_port.h"
46 
47 static int
48 nfp_flower_xmit_flow(struct net_device *netdev,
49 		     struct nfp_fl_payload *nfp_flow, u8 mtype)
50 {
51 	u32 meta_len, key_len, mask_len, act_len, tot_len;
52 	struct nfp_repr *priv = netdev_priv(netdev);
53 	struct sk_buff *skb;
54 	unsigned char *msg;
55 
56 	meta_len =  sizeof(struct nfp_fl_rule_metadata);
57 	key_len = nfp_flow->meta.key_len;
58 	mask_len = nfp_flow->meta.mask_len;
59 	act_len = nfp_flow->meta.act_len;
60 
61 	tot_len = meta_len + key_len + mask_len + act_len;
62 
63 	/* Convert to long words as firmware expects
64 	 * lengths in units of NFP_FL_LW_SIZ.
65 	 */
66 	nfp_flow->meta.key_len >>= NFP_FL_LW_SIZ;
67 	nfp_flow->meta.mask_len >>= NFP_FL_LW_SIZ;
68 	nfp_flow->meta.act_len >>= NFP_FL_LW_SIZ;
69 
70 	skb = nfp_flower_cmsg_alloc(priv->app, tot_len, mtype);
71 	if (!skb)
72 		return -ENOMEM;
73 
74 	msg = nfp_flower_cmsg_get_data(skb);
75 	memcpy(msg, &nfp_flow->meta, meta_len);
76 	memcpy(&msg[meta_len], nfp_flow->unmasked_data, key_len);
77 	memcpy(&msg[meta_len + key_len], nfp_flow->mask_data, mask_len);
78 	memcpy(&msg[meta_len + key_len + mask_len],
79 	       nfp_flow->action_data, act_len);
80 
81 	/* Convert back to bytes as software expects
82 	 * lengths in units of bytes.
83 	 */
84 	nfp_flow->meta.key_len <<= NFP_FL_LW_SIZ;
85 	nfp_flow->meta.mask_len <<= NFP_FL_LW_SIZ;
86 	nfp_flow->meta.act_len <<= NFP_FL_LW_SIZ;
87 
88 	nfp_ctrl_tx(priv->app->ctrl, skb);
89 
90 	return 0;
91 }
92 
93 static bool nfp_flower_check_higher_than_mac(struct tc_cls_flower_offload *f)
94 {
95 	return dissector_uses_key(f->dissector,
96 				  FLOW_DISSECTOR_KEY_IPV4_ADDRS) ||
97 		dissector_uses_key(f->dissector,
98 				   FLOW_DISSECTOR_KEY_IPV6_ADDRS) ||
99 		dissector_uses_key(f->dissector,
100 				   FLOW_DISSECTOR_KEY_PORTS) ||
101 		dissector_uses_key(f->dissector, FLOW_DISSECTOR_KEY_ICMP);
102 }
103 
104 static int
105 nfp_flower_calculate_key_layers(struct nfp_fl_key_ls *ret_key_ls,
106 				struct tc_cls_flower_offload *flow)
107 {
108 	struct flow_dissector_key_control *mask_enc_ctl;
109 	struct flow_dissector_key_basic *mask_basic;
110 	struct flow_dissector_key_basic *key_basic;
111 	u32 key_layer_two;
112 	u8 key_layer;
113 	int key_size;
114 
115 	mask_enc_ctl = skb_flow_dissector_target(flow->dissector,
116 						 FLOW_DISSECTOR_KEY_ENC_CONTROL,
117 						 flow->mask);
118 
119 	mask_basic = skb_flow_dissector_target(flow->dissector,
120 					       FLOW_DISSECTOR_KEY_BASIC,
121 					       flow->mask);
122 
123 	key_basic = skb_flow_dissector_target(flow->dissector,
124 					      FLOW_DISSECTOR_KEY_BASIC,
125 					      flow->key);
126 	key_layer_two = 0;
127 	key_layer = NFP_FLOWER_LAYER_PORT | NFP_FLOWER_LAYER_MAC;
128 	key_size = sizeof(struct nfp_flower_meta_one) +
129 		   sizeof(struct nfp_flower_in_port) +
130 		   sizeof(struct nfp_flower_mac_mpls);
131 
132 	/* We are expecting a tunnel. For now we ignore offloading. */
133 	if (mask_enc_ctl->addr_type)
134 		return -EOPNOTSUPP;
135 
136 	if (mask_basic->n_proto) {
137 		/* Ethernet type is present in the key. */
138 		switch (key_basic->n_proto) {
139 		case cpu_to_be16(ETH_P_IP):
140 			key_layer |= NFP_FLOWER_LAYER_IPV4;
141 			key_size += sizeof(struct nfp_flower_ipv4);
142 			break;
143 
144 		case cpu_to_be16(ETH_P_IPV6):
145 			key_layer |= NFP_FLOWER_LAYER_IPV6;
146 			key_size += sizeof(struct nfp_flower_ipv6);
147 			break;
148 
149 		/* Currently we do not offload ARP
150 		 * because we rely on it to get to the host.
151 		 */
152 		case cpu_to_be16(ETH_P_ARP):
153 			return -EOPNOTSUPP;
154 
155 		/* Will be included in layer 2. */
156 		case cpu_to_be16(ETH_P_8021Q):
157 			break;
158 
159 		default:
160 			/* Other ethtype - we need check the masks for the
161 			 * remainder of the key to ensure we can offload.
162 			 */
163 			if (nfp_flower_check_higher_than_mac(flow))
164 				return -EOPNOTSUPP;
165 			break;
166 		}
167 	}
168 
169 	if (mask_basic->ip_proto) {
170 		/* Ethernet type is present in the key. */
171 		switch (key_basic->ip_proto) {
172 		case IPPROTO_TCP:
173 		case IPPROTO_UDP:
174 		case IPPROTO_SCTP:
175 		case IPPROTO_ICMP:
176 		case IPPROTO_ICMPV6:
177 			key_layer |= NFP_FLOWER_LAYER_TP;
178 			key_size += sizeof(struct nfp_flower_tp_ports);
179 			break;
180 		default:
181 			/* Other ip proto - we need check the masks for the
182 			 * remainder of the key to ensure we can offload.
183 			 */
184 			return -EOPNOTSUPP;
185 		}
186 	}
187 
188 	ret_key_ls->key_layer = key_layer;
189 	ret_key_ls->key_layer_two = key_layer_two;
190 	ret_key_ls->key_size = key_size;
191 
192 	return 0;
193 }
194 
195 static struct nfp_fl_payload *
196 nfp_flower_allocate_new(struct nfp_fl_key_ls *key_layer)
197 {
198 	struct nfp_fl_payload *flow_pay;
199 
200 	flow_pay = kmalloc(sizeof(*flow_pay), GFP_KERNEL);
201 	if (!flow_pay)
202 		return NULL;
203 
204 	flow_pay->meta.key_len = key_layer->key_size;
205 	flow_pay->unmasked_data = kmalloc(key_layer->key_size, GFP_KERNEL);
206 	if (!flow_pay->unmasked_data)
207 		goto err_free_flow;
208 
209 	flow_pay->meta.mask_len = key_layer->key_size;
210 	flow_pay->mask_data = kmalloc(key_layer->key_size, GFP_KERNEL);
211 	if (!flow_pay->mask_data)
212 		goto err_free_unmasked;
213 
214 	flow_pay->action_data = kmalloc(NFP_FL_MAX_A_SIZ, GFP_KERNEL);
215 	if (!flow_pay->action_data)
216 		goto err_free_mask;
217 
218 	flow_pay->meta.flags = 0;
219 	spin_lock_init(&flow_pay->lock);
220 
221 	return flow_pay;
222 
223 err_free_mask:
224 	kfree(flow_pay->mask_data);
225 err_free_unmasked:
226 	kfree(flow_pay->unmasked_data);
227 err_free_flow:
228 	kfree(flow_pay);
229 	return NULL;
230 }
231 
232 /**
233  * nfp_flower_add_offload() - Adds a new flow to hardware.
234  * @app:	Pointer to the APP handle
235  * @netdev:	netdev structure.
236  * @flow:	TC flower classifier offload structure.
237  *
238  * Adds a new flow to the repeated hash structure and action payload.
239  *
240  * Return: negative value on error, 0 if configured successfully.
241  */
242 static int
243 nfp_flower_add_offload(struct nfp_app *app, struct net_device *netdev,
244 		       struct tc_cls_flower_offload *flow)
245 {
246 	struct nfp_flower_priv *priv = app->priv;
247 	struct nfp_fl_payload *flow_pay;
248 	struct nfp_fl_key_ls *key_layer;
249 	int err;
250 
251 	key_layer = kmalloc(sizeof(*key_layer), GFP_KERNEL);
252 	if (!key_layer)
253 		return -ENOMEM;
254 
255 	err = nfp_flower_calculate_key_layers(key_layer, flow);
256 	if (err)
257 		goto err_free_key_ls;
258 
259 	flow_pay = nfp_flower_allocate_new(key_layer);
260 	if (!flow_pay) {
261 		err = -ENOMEM;
262 		goto err_free_key_ls;
263 	}
264 
265 	err = nfp_flower_compile_flow_match(flow, key_layer, netdev, flow_pay);
266 	if (err)
267 		goto err_destroy_flow;
268 
269 	err = nfp_flower_compile_action(flow, netdev, flow_pay);
270 	if (err)
271 		goto err_destroy_flow;
272 
273 	err = nfp_compile_flow_metadata(app, flow, flow_pay);
274 	if (err)
275 		goto err_destroy_flow;
276 
277 	err = nfp_flower_xmit_flow(netdev, flow_pay,
278 				   NFP_FLOWER_CMSG_TYPE_FLOW_ADD);
279 	if (err)
280 		goto err_destroy_flow;
281 
282 	INIT_HLIST_NODE(&flow_pay->link);
283 	flow_pay->tc_flower_cookie = flow->cookie;
284 	hash_add_rcu(priv->flow_table, &flow_pay->link, flow->cookie);
285 
286 	/* Deallocate flow payload when flower rule has been destroyed. */
287 	kfree(key_layer);
288 
289 	return 0;
290 
291 err_destroy_flow:
292 	kfree(flow_pay->action_data);
293 	kfree(flow_pay->mask_data);
294 	kfree(flow_pay->unmasked_data);
295 	kfree(flow_pay);
296 err_free_key_ls:
297 	kfree(key_layer);
298 	return err;
299 }
300 
301 /**
302  * nfp_flower_del_offload() - Removes a flow from hardware.
303  * @app:	Pointer to the APP handle
304  * @netdev:	netdev structure.
305  * @flow:	TC flower classifier offload structure
306  *
307  * Removes a flow from the repeated hash structure and clears the
308  * action payload.
309  *
310  * Return: negative value on error, 0 if removed successfully.
311  */
312 static int
313 nfp_flower_del_offload(struct nfp_app *app, struct net_device *netdev,
314 		       struct tc_cls_flower_offload *flow)
315 {
316 	struct nfp_fl_payload *nfp_flow;
317 	int err;
318 
319 	nfp_flow = nfp_flower_search_fl_table(app, flow->cookie);
320 	if (!nfp_flow)
321 		return -ENOENT;
322 
323 	err = nfp_modify_flow_metadata(app, nfp_flow);
324 	if (err)
325 		goto err_free_flow;
326 
327 	err = nfp_flower_xmit_flow(netdev, nfp_flow,
328 				   NFP_FLOWER_CMSG_TYPE_FLOW_DEL);
329 	if (err)
330 		goto err_free_flow;
331 
332 err_free_flow:
333 	hash_del_rcu(&nfp_flow->link);
334 	kfree(nfp_flow->action_data);
335 	kfree(nfp_flow->mask_data);
336 	kfree(nfp_flow->unmasked_data);
337 	kfree_rcu(nfp_flow, rcu);
338 	return err;
339 }
340 
341 /**
342  * nfp_flower_get_stats() - Populates flow stats obtained from hardware.
343  * @app:	Pointer to the APP handle
344  * @flow:	TC flower classifier offload structure
345  *
346  * Populates a flow statistics structure which which corresponds to a
347  * specific flow.
348  *
349  * Return: negative value on error, 0 if stats populated successfully.
350  */
351 static int
352 nfp_flower_get_stats(struct nfp_app *app, struct tc_cls_flower_offload *flow)
353 {
354 	struct nfp_fl_payload *nfp_flow;
355 
356 	nfp_flow = nfp_flower_search_fl_table(app, flow->cookie);
357 	if (!nfp_flow)
358 		return -EINVAL;
359 
360 	spin_lock_bh(&nfp_flow->lock);
361 	tcf_exts_stats_update(flow->exts, nfp_flow->stats.bytes,
362 			      nfp_flow->stats.pkts, nfp_flow->stats.used);
363 
364 	nfp_flow->stats.pkts = 0;
365 	nfp_flow->stats.bytes = 0;
366 	spin_unlock_bh(&nfp_flow->lock);
367 
368 	return 0;
369 }
370 
371 static int
372 nfp_flower_repr_offload(struct nfp_app *app, struct net_device *netdev,
373 			struct tc_cls_flower_offload *flower)
374 {
375 	switch (flower->command) {
376 	case TC_CLSFLOWER_REPLACE:
377 		return nfp_flower_add_offload(app, netdev, flower);
378 	case TC_CLSFLOWER_DESTROY:
379 		return nfp_flower_del_offload(app, netdev, flower);
380 	case TC_CLSFLOWER_STATS:
381 		return nfp_flower_get_stats(app, flower);
382 	}
383 
384 	return -EOPNOTSUPP;
385 }
386 
387 int nfp_flower_setup_tc(struct nfp_app *app, struct net_device *netdev,
388 			u32 handle, __be16 proto, struct tc_to_netdev *tc)
389 {
390 	if (TC_H_MAJ(handle) != TC_H_MAJ(TC_H_INGRESS))
391 		return -EOPNOTSUPP;
392 
393 	if (!eth_proto_is_802_3(proto))
394 		return -EOPNOTSUPP;
395 
396 	if (tc->type != TC_SETUP_CLSFLOWER)
397 		return -EINVAL;
398 
399 	return nfp_flower_repr_offload(app, netdev, tc->cls_flower);
400 }
401