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