xref: /openbmc/linux/drivers/net/ethernet/netronome/nfp/bpf/main.c (revision a0ae2562c6c4b2721d9fddba63b7286c13517d9f)
1 /*
2  * Copyright (C) 2017-2018 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 <net/pkt_cls.h>
35 
36 #include "../nfpcore/nfp_cpp.h"
37 #include "../nfpcore/nfp_nffw.h"
38 #include "../nfpcore/nfp_nsp.h"
39 #include "../nfp_app.h"
40 #include "../nfp_main.h"
41 #include "../nfp_net.h"
42 #include "../nfp_port.h"
43 #include "fw.h"
44 #include "main.h"
45 
46 const struct rhashtable_params nfp_bpf_maps_neutral_params = {
47 	.nelem_hint		= 4,
48 	.key_len		= FIELD_SIZEOF(struct nfp_bpf_neutral_map, ptr),
49 	.key_offset		= offsetof(struct nfp_bpf_neutral_map, ptr),
50 	.head_offset		= offsetof(struct nfp_bpf_neutral_map, l),
51 	.automatic_shrinking	= true,
52 };
53 
54 static bool nfp_net_ebpf_capable(struct nfp_net *nn)
55 {
56 #ifdef __LITTLE_ENDIAN
57 	if (nn->cap & NFP_NET_CFG_CTRL_BPF &&
58 	    nn_readb(nn, NFP_NET_CFG_BPF_ABI) == NFP_NET_BPF_ABI)
59 		return true;
60 #endif
61 	return false;
62 }
63 
64 static int
65 nfp_bpf_xdp_offload(struct nfp_app *app, struct nfp_net *nn,
66 		    struct bpf_prog *prog, struct netlink_ext_ack *extack)
67 {
68 	bool running, xdp_running;
69 
70 	if (!nfp_net_ebpf_capable(nn))
71 		return -EINVAL;
72 
73 	running = nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF;
74 	xdp_running = running && nn->xdp_hw.prog;
75 
76 	if (!prog && !xdp_running)
77 		return 0;
78 	if (prog && running && !xdp_running)
79 		return -EBUSY;
80 
81 	return nfp_net_bpf_offload(nn, prog, running, extack);
82 }
83 
84 static const char *nfp_bpf_extra_cap(struct nfp_app *app, struct nfp_net *nn)
85 {
86 	return nfp_net_ebpf_capable(nn) ? "BPF" : "";
87 }
88 
89 static int
90 nfp_bpf_vnic_alloc(struct nfp_app *app, struct nfp_net *nn, unsigned int id)
91 {
92 	struct nfp_pf *pf = app->pf;
93 	struct nfp_bpf_vnic *bv;
94 	int err;
95 
96 	if (!pf->eth_tbl) {
97 		nfp_err(pf->cpp, "No ETH table\n");
98 		return -EINVAL;
99 	}
100 	if (pf->max_data_vnics != pf->eth_tbl->count) {
101 		nfp_err(pf->cpp, "ETH entries don't match vNICs (%d vs %d)\n",
102 			pf->max_data_vnics, pf->eth_tbl->count);
103 		return -EINVAL;
104 	}
105 
106 	bv = kzalloc(sizeof(*bv), GFP_KERNEL);
107 	if (!bv)
108 		return -ENOMEM;
109 	nn->app_priv = bv;
110 
111 	err = nfp_app_nic_vnic_alloc(app, nn, id);
112 	if (err)
113 		goto err_free_priv;
114 
115 	bv->start_off = nn_readw(nn, NFP_NET_CFG_BPF_START);
116 	bv->tgt_done = nn_readw(nn, NFP_NET_CFG_BPF_DONE);
117 
118 	return 0;
119 err_free_priv:
120 	kfree(nn->app_priv);
121 	return err;
122 }
123 
124 static void nfp_bpf_vnic_free(struct nfp_app *app, struct nfp_net *nn)
125 {
126 	struct nfp_bpf_vnic *bv = nn->app_priv;
127 
128 	WARN_ON(bv->tc_prog);
129 	kfree(bv);
130 }
131 
132 static int nfp_bpf_setup_tc_block_cb(enum tc_setup_type type,
133 				     void *type_data, void *cb_priv)
134 {
135 	struct tc_cls_bpf_offload *cls_bpf = type_data;
136 	struct nfp_net *nn = cb_priv;
137 	struct bpf_prog *oldprog;
138 	struct nfp_bpf_vnic *bv;
139 	int err;
140 
141 	if (type != TC_SETUP_CLSBPF) {
142 		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
143 				   "only offload of BPF classifiers supported");
144 		return -EOPNOTSUPP;
145 	}
146 	if (!tc_cls_can_offload_and_chain0(nn->dp.netdev, &cls_bpf->common))
147 		return -EOPNOTSUPP;
148 	if (!nfp_net_ebpf_capable(nn)) {
149 		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
150 				   "NFP firmware does not support eBPF offload");
151 		return -EOPNOTSUPP;
152 	}
153 	if (cls_bpf->common.protocol != htons(ETH_P_ALL)) {
154 		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
155 				   "only ETH_P_ALL supported as filter protocol");
156 		return -EOPNOTSUPP;
157 	}
158 
159 	/* Only support TC direct action */
160 	if (!cls_bpf->exts_integrated ||
161 	    tcf_exts_has_actions(cls_bpf->exts)) {
162 		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
163 				   "only direct action with no legacy actions supported");
164 		return -EOPNOTSUPP;
165 	}
166 
167 	if (cls_bpf->command != TC_CLSBPF_OFFLOAD)
168 		return -EOPNOTSUPP;
169 
170 	bv = nn->app_priv;
171 	oldprog = cls_bpf->oldprog;
172 
173 	/* Don't remove if oldprog doesn't match driver's state */
174 	if (bv->tc_prog != oldprog) {
175 		oldprog = NULL;
176 		if (!cls_bpf->prog)
177 			return 0;
178 	}
179 
180 	err = nfp_net_bpf_offload(nn, cls_bpf->prog, oldprog,
181 				  cls_bpf->common.extack);
182 	if (err)
183 		return err;
184 
185 	bv->tc_prog = cls_bpf->prog;
186 	nn->port->tc_offload_cnt = !!bv->tc_prog;
187 	return 0;
188 }
189 
190 static int nfp_bpf_setup_tc_block(struct net_device *netdev,
191 				  struct tc_block_offload *f)
192 {
193 	struct nfp_net *nn = netdev_priv(netdev);
194 
195 	if (f->binder_type != TCF_BLOCK_BINDER_TYPE_CLSACT_INGRESS)
196 		return -EOPNOTSUPP;
197 
198 	if (tcf_block_shared(f->block))
199 		return -EOPNOTSUPP;
200 
201 	switch (f->command) {
202 	case TC_BLOCK_BIND:
203 		return tcf_block_cb_register(f->block,
204 					     nfp_bpf_setup_tc_block_cb,
205 					     nn, nn, f->extack);
206 	case TC_BLOCK_UNBIND:
207 		tcf_block_cb_unregister(f->block,
208 					nfp_bpf_setup_tc_block_cb,
209 					nn);
210 		return 0;
211 	default:
212 		return -EOPNOTSUPP;
213 	}
214 }
215 
216 static int nfp_bpf_setup_tc(struct nfp_app *app, struct net_device *netdev,
217 			    enum tc_setup_type type, void *type_data)
218 {
219 	switch (type) {
220 	case TC_SETUP_BLOCK:
221 		return nfp_bpf_setup_tc_block(netdev, type_data);
222 	default:
223 		return -EOPNOTSUPP;
224 	}
225 }
226 
227 static int
228 nfp_bpf_check_mtu(struct nfp_app *app, struct net_device *netdev, int new_mtu)
229 {
230 	struct nfp_net *nn = netdev_priv(netdev);
231 	unsigned int max_mtu;
232 
233 	if (~nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF)
234 		return 0;
235 
236 	max_mtu = nn_readb(nn, NFP_NET_CFG_BPF_INL_MTU) * 64 - 32;
237 	if (new_mtu > max_mtu) {
238 		nn_info(nn, "BPF offload active, MTU over %u not supported\n",
239 			max_mtu);
240 		return -EBUSY;
241 	}
242 	return 0;
243 }
244 
245 static int
246 nfp_bpf_parse_cap_adjust_head(struct nfp_app_bpf *bpf, void __iomem *value,
247 			      u32 length)
248 {
249 	struct nfp_bpf_cap_tlv_adjust_head __iomem *cap = value;
250 	struct nfp_cpp *cpp = bpf->app->pf->cpp;
251 
252 	if (length < sizeof(*cap)) {
253 		nfp_err(cpp, "truncated adjust_head TLV: %d\n", length);
254 		return -EINVAL;
255 	}
256 
257 	bpf->adjust_head.flags = readl(&cap->flags);
258 	bpf->adjust_head.off_min = readl(&cap->off_min);
259 	bpf->adjust_head.off_max = readl(&cap->off_max);
260 	bpf->adjust_head.guaranteed_sub = readl(&cap->guaranteed_sub);
261 	bpf->adjust_head.guaranteed_add = readl(&cap->guaranteed_add);
262 
263 	if (bpf->adjust_head.off_min > bpf->adjust_head.off_max) {
264 		nfp_err(cpp, "invalid adjust_head TLV: min > max\n");
265 		return -EINVAL;
266 	}
267 	if (!FIELD_FIT(UR_REG_IMM_MAX, bpf->adjust_head.off_min) ||
268 	    !FIELD_FIT(UR_REG_IMM_MAX, bpf->adjust_head.off_max)) {
269 		nfp_warn(cpp, "disabling adjust_head - driver expects min/max to fit in as immediates\n");
270 		memset(&bpf->adjust_head, 0, sizeof(bpf->adjust_head));
271 		return 0;
272 	}
273 
274 	return 0;
275 }
276 
277 static int
278 nfp_bpf_parse_cap_func(struct nfp_app_bpf *bpf, void __iomem *value, u32 length)
279 {
280 	struct nfp_bpf_cap_tlv_func __iomem *cap = value;
281 
282 	if (length < sizeof(*cap)) {
283 		nfp_err(bpf->app->cpp, "truncated function TLV: %d\n", length);
284 		return -EINVAL;
285 	}
286 
287 	switch (readl(&cap->func_id)) {
288 	case BPF_FUNC_map_lookup_elem:
289 		bpf->helpers.map_lookup = readl(&cap->func_addr);
290 		break;
291 	case BPF_FUNC_map_update_elem:
292 		bpf->helpers.map_update = readl(&cap->func_addr);
293 		break;
294 	case BPF_FUNC_map_delete_elem:
295 		bpf->helpers.map_delete = readl(&cap->func_addr);
296 		break;
297 	case BPF_FUNC_perf_event_output:
298 		bpf->helpers.perf_event_output = readl(&cap->func_addr);
299 		break;
300 	}
301 
302 	return 0;
303 }
304 
305 static int
306 nfp_bpf_parse_cap_maps(struct nfp_app_bpf *bpf, void __iomem *value, u32 length)
307 {
308 	struct nfp_bpf_cap_tlv_maps __iomem *cap = value;
309 
310 	if (length < sizeof(*cap)) {
311 		nfp_err(bpf->app->cpp, "truncated maps TLV: %d\n", length);
312 		return -EINVAL;
313 	}
314 
315 	bpf->maps.types = readl(&cap->types);
316 	bpf->maps.max_maps = readl(&cap->max_maps);
317 	bpf->maps.max_elems = readl(&cap->max_elems);
318 	bpf->maps.max_key_sz = readl(&cap->max_key_sz);
319 	bpf->maps.max_val_sz = readl(&cap->max_val_sz);
320 	bpf->maps.max_elem_sz = readl(&cap->max_elem_sz);
321 
322 	return 0;
323 }
324 
325 static int
326 nfp_bpf_parse_cap_random(struct nfp_app_bpf *bpf, void __iomem *value,
327 			 u32 length)
328 {
329 	bpf->pseudo_random = true;
330 	return 0;
331 }
332 
333 static int
334 nfp_bpf_parse_cap_qsel(struct nfp_app_bpf *bpf, void __iomem *value, u32 length)
335 {
336 	bpf->queue_select = true;
337 	return 0;
338 }
339 
340 static int nfp_bpf_parse_capabilities(struct nfp_app *app)
341 {
342 	struct nfp_cpp *cpp = app->pf->cpp;
343 	struct nfp_cpp_area *area;
344 	u8 __iomem *mem, *start;
345 
346 	mem = nfp_rtsym_map(app->pf->rtbl, "_abi_bpf_capabilities", "bpf.cap",
347 			    8, &area);
348 	if (IS_ERR(mem))
349 		return PTR_ERR(mem) == -ENOENT ? 0 : PTR_ERR(mem);
350 
351 	start = mem;
352 	while (mem - start + 8 <= nfp_cpp_area_size(area)) {
353 		u8 __iomem *value;
354 		u32 type, length;
355 
356 		type = readl(mem);
357 		length = readl(mem + 4);
358 		value = mem + 8;
359 
360 		mem += 8 + length;
361 		if (mem - start > nfp_cpp_area_size(area))
362 			goto err_release_free;
363 
364 		switch (type) {
365 		case NFP_BPF_CAP_TYPE_FUNC:
366 			if (nfp_bpf_parse_cap_func(app->priv, value, length))
367 				goto err_release_free;
368 			break;
369 		case NFP_BPF_CAP_TYPE_ADJUST_HEAD:
370 			if (nfp_bpf_parse_cap_adjust_head(app->priv, value,
371 							  length))
372 				goto err_release_free;
373 			break;
374 		case NFP_BPF_CAP_TYPE_MAPS:
375 			if (nfp_bpf_parse_cap_maps(app->priv, value, length))
376 				goto err_release_free;
377 			break;
378 		case NFP_BPF_CAP_TYPE_RANDOM:
379 			if (nfp_bpf_parse_cap_random(app->priv, value, length))
380 				goto err_release_free;
381 			break;
382 		case NFP_BPF_CAP_TYPE_QUEUE_SELECT:
383 			if (nfp_bpf_parse_cap_qsel(app->priv, value, length))
384 				goto err_release_free;
385 			break;
386 		default:
387 			nfp_dbg(cpp, "unknown BPF capability: %d\n", type);
388 			break;
389 		}
390 	}
391 	if (mem - start != nfp_cpp_area_size(area)) {
392 		nfp_err(cpp, "BPF capabilities left after parsing, parsed:%zd total length:%zu\n",
393 			mem - start, nfp_cpp_area_size(area));
394 		goto err_release_free;
395 	}
396 
397 	nfp_cpp_area_release_free(area);
398 
399 	return 0;
400 
401 err_release_free:
402 	nfp_err(cpp, "invalid BPF capabilities at offset:%zd\n", mem - start);
403 	nfp_cpp_area_release_free(area);
404 	return -EINVAL;
405 }
406 
407 static int nfp_bpf_init(struct nfp_app *app)
408 {
409 	struct nfp_app_bpf *bpf;
410 	int err;
411 
412 	bpf = kzalloc(sizeof(*bpf), GFP_KERNEL);
413 	if (!bpf)
414 		return -ENOMEM;
415 	bpf->app = app;
416 	app->priv = bpf;
417 
418 	skb_queue_head_init(&bpf->cmsg_replies);
419 	init_waitqueue_head(&bpf->cmsg_wq);
420 	INIT_LIST_HEAD(&bpf->map_list);
421 
422 	err = rhashtable_init(&bpf->maps_neutral, &nfp_bpf_maps_neutral_params);
423 	if (err)
424 		goto err_free_bpf;
425 
426 	err = nfp_bpf_parse_capabilities(app);
427 	if (err)
428 		goto err_free_neutral_maps;
429 
430 	return 0;
431 
432 err_free_neutral_maps:
433 	rhashtable_destroy(&bpf->maps_neutral);
434 err_free_bpf:
435 	kfree(bpf);
436 	return err;
437 }
438 
439 static void nfp_check_rhashtable_empty(void *ptr, void *arg)
440 {
441 	WARN_ON_ONCE(1);
442 }
443 
444 static void nfp_bpf_clean(struct nfp_app *app)
445 {
446 	struct nfp_app_bpf *bpf = app->priv;
447 
448 	WARN_ON(!skb_queue_empty(&bpf->cmsg_replies));
449 	WARN_ON(!list_empty(&bpf->map_list));
450 	WARN_ON(bpf->maps_in_use || bpf->map_elems_in_use);
451 	rhashtable_free_and_destroy(&bpf->maps_neutral,
452 				    nfp_check_rhashtable_empty, NULL);
453 	kfree(bpf);
454 }
455 
456 const struct nfp_app_type app_bpf = {
457 	.id		= NFP_APP_BPF_NIC,
458 	.name		= "ebpf",
459 
460 	.ctrl_cap_mask	= 0,
461 
462 	.init		= nfp_bpf_init,
463 	.clean		= nfp_bpf_clean,
464 
465 	.check_mtu	= nfp_bpf_check_mtu,
466 
467 	.extra_cap	= nfp_bpf_extra_cap,
468 
469 	.vnic_alloc	= nfp_bpf_vnic_alloc,
470 	.vnic_free	= nfp_bpf_vnic_free,
471 
472 	.ctrl_msg_rx	= nfp_bpf_ctrl_msg_rx,
473 
474 	.setup_tc	= nfp_bpf_setup_tc,
475 	.bpf		= nfp_ndo_bpf,
476 	.xdp_offload	= nfp_bpf_xdp_offload,
477 };
478