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 	int ret;
70 
71 	if (!nfp_net_ebpf_capable(nn))
72 		return -EINVAL;
73 
74 	running = nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF;
75 	xdp_running = running && nn->dp.bpf_offload_xdp;
76 
77 	if (!prog && !xdp_running)
78 		return 0;
79 	if (prog && running && !xdp_running)
80 		return -EBUSY;
81 
82 	ret = nfp_net_bpf_offload(nn, prog, running, extack);
83 	/* Stop offload if replace not possible */
84 	if (ret && prog)
85 		nfp_bpf_xdp_offload(app, nn, NULL, extack);
86 
87 	nn->dp.bpf_offload_xdp = prog && !ret;
88 	return ret;
89 }
90 
91 static const char *nfp_bpf_extra_cap(struct nfp_app *app, struct nfp_net *nn)
92 {
93 	return nfp_net_ebpf_capable(nn) ? "BPF" : "";
94 }
95 
96 static int
97 nfp_bpf_vnic_alloc(struct nfp_app *app, struct nfp_net *nn, unsigned int id)
98 {
99 	struct nfp_pf *pf = app->pf;
100 	struct nfp_bpf_vnic *bv;
101 	int err;
102 
103 	if (!pf->eth_tbl) {
104 		nfp_err(pf->cpp, "No ETH table\n");
105 		return -EINVAL;
106 	}
107 	if (pf->max_data_vnics != pf->eth_tbl->count) {
108 		nfp_err(pf->cpp, "ETH entries don't match vNICs (%d vs %d)\n",
109 			pf->max_data_vnics, pf->eth_tbl->count);
110 		return -EINVAL;
111 	}
112 
113 	bv = kzalloc(sizeof(*bv), GFP_KERNEL);
114 	if (!bv)
115 		return -ENOMEM;
116 	nn->app_priv = bv;
117 
118 	err = nfp_app_nic_vnic_alloc(app, nn, id);
119 	if (err)
120 		goto err_free_priv;
121 
122 	bv->start_off = nn_readw(nn, NFP_NET_CFG_BPF_START);
123 	bv->tgt_done = nn_readw(nn, NFP_NET_CFG_BPF_DONE);
124 
125 	return 0;
126 err_free_priv:
127 	kfree(nn->app_priv);
128 	return err;
129 }
130 
131 static void nfp_bpf_vnic_free(struct nfp_app *app, struct nfp_net *nn)
132 {
133 	struct nfp_bpf_vnic *bv = nn->app_priv;
134 
135 	WARN_ON(bv->tc_prog);
136 	kfree(bv);
137 }
138 
139 static int nfp_bpf_setup_tc_block_cb(enum tc_setup_type type,
140 				     void *type_data, void *cb_priv)
141 {
142 	struct tc_cls_bpf_offload *cls_bpf = type_data;
143 	struct nfp_net *nn = cb_priv;
144 	struct bpf_prog *oldprog;
145 	struct nfp_bpf_vnic *bv;
146 	int err;
147 
148 	if (type != TC_SETUP_CLSBPF) {
149 		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
150 				   "only offload of BPF classifiers supported");
151 		return -EOPNOTSUPP;
152 	}
153 	if (!tc_cls_can_offload_and_chain0(nn->dp.netdev, &cls_bpf->common))
154 		return -EOPNOTSUPP;
155 	if (!nfp_net_ebpf_capable(nn)) {
156 		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
157 				   "NFP firmware does not support eBPF offload");
158 		return -EOPNOTSUPP;
159 	}
160 	if (cls_bpf->common.protocol != htons(ETH_P_ALL)) {
161 		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
162 				   "only ETH_P_ALL supported as filter protocol");
163 		return -EOPNOTSUPP;
164 	}
165 
166 	/* Only support TC direct action */
167 	if (!cls_bpf->exts_integrated ||
168 	    tcf_exts_has_actions(cls_bpf->exts)) {
169 		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
170 				   "only direct action with no legacy actions supported");
171 		return -EOPNOTSUPP;
172 	}
173 
174 	if (cls_bpf->command != TC_CLSBPF_OFFLOAD)
175 		return -EOPNOTSUPP;
176 
177 	bv = nn->app_priv;
178 	oldprog = cls_bpf->oldprog;
179 
180 	/* Don't remove if oldprog doesn't match driver's state */
181 	if (bv->tc_prog != oldprog) {
182 		oldprog = NULL;
183 		if (!cls_bpf->prog)
184 			return 0;
185 	}
186 
187 	err = nfp_net_bpf_offload(nn, cls_bpf->prog, oldprog,
188 				  cls_bpf->common.extack);
189 	if (err)
190 		return err;
191 
192 	bv->tc_prog = cls_bpf->prog;
193 	nn->port->tc_offload_cnt = !!bv->tc_prog;
194 	return 0;
195 }
196 
197 static int nfp_bpf_setup_tc_block(struct net_device *netdev,
198 				  struct tc_block_offload *f)
199 {
200 	struct nfp_net *nn = netdev_priv(netdev);
201 
202 	if (f->binder_type != TCF_BLOCK_BINDER_TYPE_CLSACT_INGRESS)
203 		return -EOPNOTSUPP;
204 
205 	switch (f->command) {
206 	case TC_BLOCK_BIND:
207 		return tcf_block_cb_register(f->block,
208 					     nfp_bpf_setup_tc_block_cb,
209 					     nn, nn);
210 	case TC_BLOCK_UNBIND:
211 		tcf_block_cb_unregister(f->block,
212 					nfp_bpf_setup_tc_block_cb,
213 					nn);
214 		return 0;
215 	default:
216 		return -EOPNOTSUPP;
217 	}
218 }
219 
220 static int nfp_bpf_setup_tc(struct nfp_app *app, struct net_device *netdev,
221 			    enum tc_setup_type type, void *type_data)
222 {
223 	switch (type) {
224 	case TC_SETUP_BLOCK:
225 		return nfp_bpf_setup_tc_block(netdev, type_data);
226 	default:
227 		return -EOPNOTSUPP;
228 	}
229 }
230 
231 static int
232 nfp_bpf_check_mtu(struct nfp_app *app, struct net_device *netdev, int new_mtu)
233 {
234 	struct nfp_net *nn = netdev_priv(netdev);
235 	unsigned int max_mtu;
236 
237 	if (~nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF)
238 		return 0;
239 
240 	max_mtu = nn_readb(nn, NFP_NET_CFG_BPF_INL_MTU) * 64 - 32;
241 	if (new_mtu > max_mtu) {
242 		nn_info(nn, "BPF offload active, MTU over %u not supported\n",
243 			max_mtu);
244 		return -EBUSY;
245 	}
246 	return 0;
247 }
248 
249 static int
250 nfp_bpf_parse_cap_adjust_head(struct nfp_app_bpf *bpf, void __iomem *value,
251 			      u32 length)
252 {
253 	struct nfp_bpf_cap_tlv_adjust_head __iomem *cap = value;
254 	struct nfp_cpp *cpp = bpf->app->pf->cpp;
255 
256 	if (length < sizeof(*cap)) {
257 		nfp_err(cpp, "truncated adjust_head TLV: %d\n", length);
258 		return -EINVAL;
259 	}
260 
261 	bpf->adjust_head.flags = readl(&cap->flags);
262 	bpf->adjust_head.off_min = readl(&cap->off_min);
263 	bpf->adjust_head.off_max = readl(&cap->off_max);
264 	bpf->adjust_head.guaranteed_sub = readl(&cap->guaranteed_sub);
265 	bpf->adjust_head.guaranteed_add = readl(&cap->guaranteed_add);
266 
267 	if (bpf->adjust_head.off_min > bpf->adjust_head.off_max) {
268 		nfp_err(cpp, "invalid adjust_head TLV: min > max\n");
269 		return -EINVAL;
270 	}
271 	if (!FIELD_FIT(UR_REG_IMM_MAX, bpf->adjust_head.off_min) ||
272 	    !FIELD_FIT(UR_REG_IMM_MAX, bpf->adjust_head.off_max)) {
273 		nfp_warn(cpp, "disabling adjust_head - driver expects min/max to fit in as immediates\n");
274 		memset(&bpf->adjust_head, 0, sizeof(bpf->adjust_head));
275 		return 0;
276 	}
277 
278 	return 0;
279 }
280 
281 static int
282 nfp_bpf_parse_cap_func(struct nfp_app_bpf *bpf, void __iomem *value, u32 length)
283 {
284 	struct nfp_bpf_cap_tlv_func __iomem *cap = value;
285 
286 	if (length < sizeof(*cap)) {
287 		nfp_err(bpf->app->cpp, "truncated function TLV: %d\n", length);
288 		return -EINVAL;
289 	}
290 
291 	switch (readl(&cap->func_id)) {
292 	case BPF_FUNC_map_lookup_elem:
293 		bpf->helpers.map_lookup = readl(&cap->func_addr);
294 		break;
295 	case BPF_FUNC_map_update_elem:
296 		bpf->helpers.map_update = readl(&cap->func_addr);
297 		break;
298 	case BPF_FUNC_map_delete_elem:
299 		bpf->helpers.map_delete = readl(&cap->func_addr);
300 		break;
301 	case BPF_FUNC_perf_event_output:
302 		bpf->helpers.perf_event_output = readl(&cap->func_addr);
303 		break;
304 	}
305 
306 	return 0;
307 }
308 
309 static int
310 nfp_bpf_parse_cap_maps(struct nfp_app_bpf *bpf, void __iomem *value, u32 length)
311 {
312 	struct nfp_bpf_cap_tlv_maps __iomem *cap = value;
313 
314 	if (length < sizeof(*cap)) {
315 		nfp_err(bpf->app->cpp, "truncated maps TLV: %d\n", length);
316 		return -EINVAL;
317 	}
318 
319 	bpf->maps.types = readl(&cap->types);
320 	bpf->maps.max_maps = readl(&cap->max_maps);
321 	bpf->maps.max_elems = readl(&cap->max_elems);
322 	bpf->maps.max_key_sz = readl(&cap->max_key_sz);
323 	bpf->maps.max_val_sz = readl(&cap->max_val_sz);
324 	bpf->maps.max_elem_sz = readl(&cap->max_elem_sz);
325 
326 	return 0;
327 }
328 
329 static int
330 nfp_bpf_parse_cap_random(struct nfp_app_bpf *bpf, void __iomem *value,
331 			 u32 length)
332 {
333 	bpf->pseudo_random = true;
334 	return 0;
335 }
336 
337 static int
338 nfp_bpf_parse_cap_qsel(struct nfp_app_bpf *bpf, void __iomem *value, u32 length)
339 {
340 	bpf->queue_select = true;
341 	return 0;
342 }
343 
344 static int nfp_bpf_parse_capabilities(struct nfp_app *app)
345 {
346 	struct nfp_cpp *cpp = app->pf->cpp;
347 	struct nfp_cpp_area *area;
348 	u8 __iomem *mem, *start;
349 
350 	mem = nfp_rtsym_map(app->pf->rtbl, "_abi_bpf_capabilities", "bpf.cap",
351 			    8, &area);
352 	if (IS_ERR(mem))
353 		return PTR_ERR(mem) == -ENOENT ? 0 : PTR_ERR(mem);
354 
355 	start = mem;
356 	while (mem - start + 8 <= nfp_cpp_area_size(area)) {
357 		u8 __iomem *value;
358 		u32 type, length;
359 
360 		type = readl(mem);
361 		length = readl(mem + 4);
362 		value = mem + 8;
363 
364 		mem += 8 + length;
365 		if (mem - start > nfp_cpp_area_size(area))
366 			goto err_release_free;
367 
368 		switch (type) {
369 		case NFP_BPF_CAP_TYPE_FUNC:
370 			if (nfp_bpf_parse_cap_func(app->priv, value, length))
371 				goto err_release_free;
372 			break;
373 		case NFP_BPF_CAP_TYPE_ADJUST_HEAD:
374 			if (nfp_bpf_parse_cap_adjust_head(app->priv, value,
375 							  length))
376 				goto err_release_free;
377 			break;
378 		case NFP_BPF_CAP_TYPE_MAPS:
379 			if (nfp_bpf_parse_cap_maps(app->priv, value, length))
380 				goto err_release_free;
381 			break;
382 		case NFP_BPF_CAP_TYPE_RANDOM:
383 			if (nfp_bpf_parse_cap_random(app->priv, value, length))
384 				goto err_release_free;
385 			break;
386 		case NFP_BPF_CAP_TYPE_QUEUE_SELECT:
387 			if (nfp_bpf_parse_cap_qsel(app->priv, value, length))
388 				goto err_release_free;
389 			break;
390 		default:
391 			nfp_dbg(cpp, "unknown BPF capability: %d\n", type);
392 			break;
393 		}
394 	}
395 	if (mem - start != nfp_cpp_area_size(area)) {
396 		nfp_err(cpp, "BPF capabilities left after parsing, parsed:%zd total length:%zu\n",
397 			mem - start, nfp_cpp_area_size(area));
398 		goto err_release_free;
399 	}
400 
401 	nfp_cpp_area_release_free(area);
402 
403 	return 0;
404 
405 err_release_free:
406 	nfp_err(cpp, "invalid BPF capabilities at offset:%zd\n", mem - start);
407 	nfp_cpp_area_release_free(area);
408 	return -EINVAL;
409 }
410 
411 static int nfp_bpf_init(struct nfp_app *app)
412 {
413 	struct nfp_app_bpf *bpf;
414 	int err;
415 
416 	bpf = kzalloc(sizeof(*bpf), GFP_KERNEL);
417 	if (!bpf)
418 		return -ENOMEM;
419 	bpf->app = app;
420 	app->priv = bpf;
421 
422 	skb_queue_head_init(&bpf->cmsg_replies);
423 	init_waitqueue_head(&bpf->cmsg_wq);
424 	INIT_LIST_HEAD(&bpf->map_list);
425 
426 	err = rhashtable_init(&bpf->maps_neutral, &nfp_bpf_maps_neutral_params);
427 	if (err)
428 		goto err_free_bpf;
429 
430 	err = nfp_bpf_parse_capabilities(app);
431 	if (err)
432 		goto err_free_neutral_maps;
433 
434 	return 0;
435 
436 err_free_neutral_maps:
437 	rhashtable_destroy(&bpf->maps_neutral);
438 err_free_bpf:
439 	kfree(bpf);
440 	return err;
441 }
442 
443 static void nfp_check_rhashtable_empty(void *ptr, void *arg)
444 {
445 	WARN_ON_ONCE(1);
446 }
447 
448 static void nfp_bpf_clean(struct nfp_app *app)
449 {
450 	struct nfp_app_bpf *bpf = app->priv;
451 
452 	WARN_ON(!skb_queue_empty(&bpf->cmsg_replies));
453 	WARN_ON(!list_empty(&bpf->map_list));
454 	WARN_ON(bpf->maps_in_use || bpf->map_elems_in_use);
455 	rhashtable_free_and_destroy(&bpf->maps_neutral,
456 				    nfp_check_rhashtable_empty, NULL);
457 	kfree(bpf);
458 }
459 
460 const struct nfp_app_type app_bpf = {
461 	.id		= NFP_APP_BPF_NIC,
462 	.name		= "ebpf",
463 
464 	.ctrl_cap_mask	= 0,
465 
466 	.init		= nfp_bpf_init,
467 	.clean		= nfp_bpf_clean,
468 
469 	.check_mtu	= nfp_bpf_check_mtu,
470 
471 	.extra_cap	= nfp_bpf_extra_cap,
472 
473 	.vnic_alloc	= nfp_bpf_vnic_alloc,
474 	.vnic_free	= nfp_bpf_vnic_free,
475 
476 	.ctrl_msg_rx	= nfp_bpf_ctrl_msg_rx,
477 
478 	.setup_tc	= nfp_bpf_setup_tc,
479 	.bpf		= nfp_ndo_bpf,
480 	.xdp_offload	= nfp_bpf_xdp_offload,
481 };
482