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 bpf_map, id),
49 	.key_offset		= offsetof(struct nfp_bpf_neutral_map, map_id),
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 	switch (f->command) {
199 	case TC_BLOCK_BIND:
200 		return tcf_block_cb_register(f->block,
201 					     nfp_bpf_setup_tc_block_cb,
202 					     nn, nn, f->extack);
203 	case TC_BLOCK_UNBIND:
204 		tcf_block_cb_unregister(f->block,
205 					nfp_bpf_setup_tc_block_cb,
206 					nn);
207 		return 0;
208 	default:
209 		return -EOPNOTSUPP;
210 	}
211 }
212 
213 static int nfp_bpf_setup_tc(struct nfp_app *app, struct net_device *netdev,
214 			    enum tc_setup_type type, void *type_data)
215 {
216 	switch (type) {
217 	case TC_SETUP_BLOCK:
218 		return nfp_bpf_setup_tc_block(netdev, type_data);
219 	default:
220 		return -EOPNOTSUPP;
221 	}
222 }
223 
224 static int
225 nfp_bpf_check_mtu(struct nfp_app *app, struct net_device *netdev, int new_mtu)
226 {
227 	struct nfp_net *nn = netdev_priv(netdev);
228 	unsigned int max_mtu;
229 
230 	if (~nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF)
231 		return 0;
232 
233 	max_mtu = nn_readb(nn, NFP_NET_CFG_BPF_INL_MTU) * 64 - 32;
234 	if (new_mtu > max_mtu) {
235 		nn_info(nn, "BPF offload active, MTU over %u not supported\n",
236 			max_mtu);
237 		return -EBUSY;
238 	}
239 	return 0;
240 }
241 
242 static int
243 nfp_bpf_parse_cap_adjust_head(struct nfp_app_bpf *bpf, void __iomem *value,
244 			      u32 length)
245 {
246 	struct nfp_bpf_cap_tlv_adjust_head __iomem *cap = value;
247 	struct nfp_cpp *cpp = bpf->app->pf->cpp;
248 
249 	if (length < sizeof(*cap)) {
250 		nfp_err(cpp, "truncated adjust_head TLV: %d\n", length);
251 		return -EINVAL;
252 	}
253 
254 	bpf->adjust_head.flags = readl(&cap->flags);
255 	bpf->adjust_head.off_min = readl(&cap->off_min);
256 	bpf->adjust_head.off_max = readl(&cap->off_max);
257 	bpf->adjust_head.guaranteed_sub = readl(&cap->guaranteed_sub);
258 	bpf->adjust_head.guaranteed_add = readl(&cap->guaranteed_add);
259 
260 	if (bpf->adjust_head.off_min > bpf->adjust_head.off_max) {
261 		nfp_err(cpp, "invalid adjust_head TLV: min > max\n");
262 		return -EINVAL;
263 	}
264 	if (!FIELD_FIT(UR_REG_IMM_MAX, bpf->adjust_head.off_min) ||
265 	    !FIELD_FIT(UR_REG_IMM_MAX, bpf->adjust_head.off_max)) {
266 		nfp_warn(cpp, "disabling adjust_head - driver expects min/max to fit in as immediates\n");
267 		memset(&bpf->adjust_head, 0, sizeof(bpf->adjust_head));
268 		return 0;
269 	}
270 
271 	return 0;
272 }
273 
274 static int
275 nfp_bpf_parse_cap_func(struct nfp_app_bpf *bpf, void __iomem *value, u32 length)
276 {
277 	struct nfp_bpf_cap_tlv_func __iomem *cap = value;
278 
279 	if (length < sizeof(*cap)) {
280 		nfp_err(bpf->app->cpp, "truncated function TLV: %d\n", length);
281 		return -EINVAL;
282 	}
283 
284 	switch (readl(&cap->func_id)) {
285 	case BPF_FUNC_map_lookup_elem:
286 		bpf->helpers.map_lookup = readl(&cap->func_addr);
287 		break;
288 	case BPF_FUNC_map_update_elem:
289 		bpf->helpers.map_update = readl(&cap->func_addr);
290 		break;
291 	case BPF_FUNC_map_delete_elem:
292 		bpf->helpers.map_delete = readl(&cap->func_addr);
293 		break;
294 	case BPF_FUNC_perf_event_output:
295 		bpf->helpers.perf_event_output = readl(&cap->func_addr);
296 		break;
297 	}
298 
299 	return 0;
300 }
301 
302 static int
303 nfp_bpf_parse_cap_maps(struct nfp_app_bpf *bpf, void __iomem *value, u32 length)
304 {
305 	struct nfp_bpf_cap_tlv_maps __iomem *cap = value;
306 
307 	if (length < sizeof(*cap)) {
308 		nfp_err(bpf->app->cpp, "truncated maps TLV: %d\n", length);
309 		return -EINVAL;
310 	}
311 
312 	bpf->maps.types = readl(&cap->types);
313 	bpf->maps.max_maps = readl(&cap->max_maps);
314 	bpf->maps.max_elems = readl(&cap->max_elems);
315 	bpf->maps.max_key_sz = readl(&cap->max_key_sz);
316 	bpf->maps.max_val_sz = readl(&cap->max_val_sz);
317 	bpf->maps.max_elem_sz = readl(&cap->max_elem_sz);
318 
319 	return 0;
320 }
321 
322 static int
323 nfp_bpf_parse_cap_random(struct nfp_app_bpf *bpf, void __iomem *value,
324 			 u32 length)
325 {
326 	bpf->pseudo_random = true;
327 	return 0;
328 }
329 
330 static int
331 nfp_bpf_parse_cap_qsel(struct nfp_app_bpf *bpf, void __iomem *value, u32 length)
332 {
333 	bpf->queue_select = true;
334 	return 0;
335 }
336 
337 static int
338 nfp_bpf_parse_cap_adjust_tail(struct nfp_app_bpf *bpf, void __iomem *value,
339 			      u32 length)
340 {
341 	bpf->adjust_tail = true;
342 	return 0;
343 }
344 
345 static int nfp_bpf_parse_capabilities(struct nfp_app *app)
346 {
347 	struct nfp_cpp *cpp = app->pf->cpp;
348 	struct nfp_cpp_area *area;
349 	u8 __iomem *mem, *start;
350 
351 	mem = nfp_rtsym_map(app->pf->rtbl, "_abi_bpf_capabilities", "bpf.cap",
352 			    8, &area);
353 	if (IS_ERR(mem))
354 		return PTR_ERR(mem) == -ENOENT ? 0 : PTR_ERR(mem);
355 
356 	start = mem;
357 	while (mem - start + 8 <= nfp_cpp_area_size(area)) {
358 		u8 __iomem *value;
359 		u32 type, length;
360 
361 		type = readl(mem);
362 		length = readl(mem + 4);
363 		value = mem + 8;
364 
365 		mem += 8 + length;
366 		if (mem - start > nfp_cpp_area_size(area))
367 			goto err_release_free;
368 
369 		switch (type) {
370 		case NFP_BPF_CAP_TYPE_FUNC:
371 			if (nfp_bpf_parse_cap_func(app->priv, value, length))
372 				goto err_release_free;
373 			break;
374 		case NFP_BPF_CAP_TYPE_ADJUST_HEAD:
375 			if (nfp_bpf_parse_cap_adjust_head(app->priv, value,
376 							  length))
377 				goto err_release_free;
378 			break;
379 		case NFP_BPF_CAP_TYPE_MAPS:
380 			if (nfp_bpf_parse_cap_maps(app->priv, value, length))
381 				goto err_release_free;
382 			break;
383 		case NFP_BPF_CAP_TYPE_RANDOM:
384 			if (nfp_bpf_parse_cap_random(app->priv, value, length))
385 				goto err_release_free;
386 			break;
387 		case NFP_BPF_CAP_TYPE_QUEUE_SELECT:
388 			if (nfp_bpf_parse_cap_qsel(app->priv, value, length))
389 				goto err_release_free;
390 			break;
391 		case NFP_BPF_CAP_TYPE_ADJUST_TAIL:
392 			if (nfp_bpf_parse_cap_adjust_tail(app->priv, value,
393 							  length))
394 				goto err_release_free;
395 			break;
396 		default:
397 			nfp_dbg(cpp, "unknown BPF capability: %d\n", type);
398 			break;
399 		}
400 	}
401 	if (mem - start != nfp_cpp_area_size(area)) {
402 		nfp_err(cpp, "BPF capabilities left after parsing, parsed:%zd total length:%zu\n",
403 			mem - start, nfp_cpp_area_size(area));
404 		goto err_release_free;
405 	}
406 
407 	nfp_cpp_area_release_free(area);
408 
409 	return 0;
410 
411 err_release_free:
412 	nfp_err(cpp, "invalid BPF capabilities at offset:%zd\n", mem - start);
413 	nfp_cpp_area_release_free(area);
414 	return -EINVAL;
415 }
416 
417 static int nfp_bpf_ndo_init(struct nfp_app *app, struct net_device *netdev)
418 {
419 	struct nfp_app_bpf *bpf = app->priv;
420 
421 	return bpf_offload_dev_netdev_register(bpf->bpf_dev, netdev);
422 }
423 
424 static void nfp_bpf_ndo_uninit(struct nfp_app *app, struct net_device *netdev)
425 {
426 	struct nfp_app_bpf *bpf = app->priv;
427 
428 	bpf_offload_dev_netdev_unregister(bpf->bpf_dev, netdev);
429 }
430 
431 static int nfp_bpf_init(struct nfp_app *app)
432 {
433 	struct nfp_app_bpf *bpf;
434 	int err;
435 
436 	bpf = kzalloc(sizeof(*bpf), GFP_KERNEL);
437 	if (!bpf)
438 		return -ENOMEM;
439 	bpf->app = app;
440 	app->priv = bpf;
441 
442 	skb_queue_head_init(&bpf->cmsg_replies);
443 	init_waitqueue_head(&bpf->cmsg_wq);
444 	INIT_LIST_HEAD(&bpf->map_list);
445 
446 	err = rhashtable_init(&bpf->maps_neutral, &nfp_bpf_maps_neutral_params);
447 	if (err)
448 		goto err_free_bpf;
449 
450 	err = nfp_bpf_parse_capabilities(app);
451 	if (err)
452 		goto err_free_neutral_maps;
453 
454 	bpf->bpf_dev = bpf_offload_dev_create();
455 	err = PTR_ERR_OR_ZERO(bpf->bpf_dev);
456 	if (err)
457 		goto err_free_neutral_maps;
458 
459 	return 0;
460 
461 err_free_neutral_maps:
462 	rhashtable_destroy(&bpf->maps_neutral);
463 err_free_bpf:
464 	kfree(bpf);
465 	return err;
466 }
467 
468 static void nfp_check_rhashtable_empty(void *ptr, void *arg)
469 {
470 	WARN_ON_ONCE(1);
471 }
472 
473 static void nfp_bpf_clean(struct nfp_app *app)
474 {
475 	struct nfp_app_bpf *bpf = app->priv;
476 
477 	bpf_offload_dev_destroy(bpf->bpf_dev);
478 	WARN_ON(!skb_queue_empty(&bpf->cmsg_replies));
479 	WARN_ON(!list_empty(&bpf->map_list));
480 	WARN_ON(bpf->maps_in_use || bpf->map_elems_in_use);
481 	rhashtable_free_and_destroy(&bpf->maps_neutral,
482 				    nfp_check_rhashtable_empty, NULL);
483 	kfree(bpf);
484 }
485 
486 const struct nfp_app_type app_bpf = {
487 	.id		= NFP_APP_BPF_NIC,
488 	.name		= "ebpf",
489 
490 	.ctrl_cap_mask	= 0,
491 
492 	.init		= nfp_bpf_init,
493 	.clean		= nfp_bpf_clean,
494 
495 	.check_mtu	= nfp_bpf_check_mtu,
496 
497 	.extra_cap	= nfp_bpf_extra_cap,
498 
499 	.ndo_init	= nfp_bpf_ndo_init,
500 	.ndo_uninit	= nfp_bpf_ndo_uninit,
501 
502 	.vnic_alloc	= nfp_bpf_vnic_alloc,
503 	.vnic_free	= nfp_bpf_vnic_free,
504 
505 	.ctrl_msg_rx	= nfp_bpf_ctrl_msg_rx,
506 	.ctrl_msg_rx_raw	= nfp_bpf_ctrl_msg_rx_raw,
507 
508 	.setup_tc	= nfp_bpf_setup_tc,
509 	.bpf		= nfp_ndo_bpf,
510 	.xdp_offload	= nfp_bpf_xdp_offload,
511 };
512