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 "../nfp_app.h"
38 #include "../nfp_main.h"
39 #include "../nfp_net.h"
40 #include "../nfp_port.h"
41 #include "main.h"
42 
43 static bool nfp_net_ebpf_capable(struct nfp_net *nn)
44 {
45 #ifdef __LITTLE_ENDIAN
46 	if (nn->cap & NFP_NET_CFG_CTRL_BPF &&
47 	    nn_readb(nn, NFP_NET_CFG_BPF_ABI) == NFP_NET_BPF_ABI)
48 		return true;
49 #endif
50 	return false;
51 }
52 
53 static int
54 nfp_bpf_xdp_offload(struct nfp_app *app, struct nfp_net *nn,
55 		    struct bpf_prog *prog)
56 {
57 	bool running, xdp_running;
58 	int ret;
59 
60 	if (!nfp_net_ebpf_capable(nn))
61 		return -EINVAL;
62 
63 	running = nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF;
64 	xdp_running = running && nn->dp.bpf_offload_xdp;
65 
66 	if (!prog && !xdp_running)
67 		return 0;
68 	if (prog && running && !xdp_running)
69 		return -EBUSY;
70 
71 	ret = nfp_net_bpf_offload(nn, prog, running);
72 	/* Stop offload if replace not possible */
73 	if (ret && prog)
74 		nfp_bpf_xdp_offload(app, nn, NULL);
75 
76 	nn->dp.bpf_offload_xdp = prog && !ret;
77 	return ret;
78 }
79 
80 static const char *nfp_bpf_extra_cap(struct nfp_app *app, struct nfp_net *nn)
81 {
82 	return nfp_net_ebpf_capable(nn) ? "BPF" : "";
83 }
84 
85 static void nfp_bpf_vnic_free(struct nfp_app *app, struct nfp_net *nn)
86 {
87 	if (nn->dp.bpf_offload_xdp)
88 		nfp_bpf_xdp_offload(app, nn, NULL);
89 }
90 
91 static int nfp_bpf_setup_tc_block_cb(enum tc_setup_type type,
92 				     void *type_data, void *cb_priv)
93 {
94 	struct tc_cls_bpf_offload *cls_bpf = type_data;
95 	struct nfp_net *nn = cb_priv;
96 
97 	if (type != TC_SETUP_CLSBPF ||
98 	    !tc_can_offload(nn->dp.netdev) ||
99 	    !nfp_net_ebpf_capable(nn) ||
100 	    cls_bpf->common.protocol != htons(ETH_P_ALL) ||
101 	    cls_bpf->common.chain_index)
102 		return -EOPNOTSUPP;
103 	if (nn->dp.bpf_offload_xdp)
104 		return -EBUSY;
105 
106 	/* Only support TC direct action */
107 	if (!cls_bpf->exts_integrated ||
108 	    tcf_exts_has_actions(cls_bpf->exts)) {
109 		nn_err(nn, "only direct action with no legacy actions supported\n");
110 		return -EOPNOTSUPP;
111 	}
112 
113 	switch (cls_bpf->command) {
114 	case TC_CLSBPF_REPLACE:
115 		return nfp_net_bpf_offload(nn, cls_bpf->prog, true);
116 	case TC_CLSBPF_ADD:
117 		return nfp_net_bpf_offload(nn, cls_bpf->prog, false);
118 	case TC_CLSBPF_DESTROY:
119 		return nfp_net_bpf_offload(nn, NULL, true);
120 	default:
121 		return -EOPNOTSUPP;
122 	}
123 }
124 
125 static int nfp_bpf_setup_tc_block(struct net_device *netdev,
126 				  struct tc_block_offload *f)
127 {
128 	struct nfp_net *nn = netdev_priv(netdev);
129 
130 	if (f->binder_type != TCF_BLOCK_BINDER_TYPE_CLSACT_INGRESS)
131 		return -EOPNOTSUPP;
132 
133 	switch (f->command) {
134 	case TC_BLOCK_BIND:
135 		return tcf_block_cb_register(f->block,
136 					     nfp_bpf_setup_tc_block_cb,
137 					     nn, nn);
138 	case TC_BLOCK_UNBIND:
139 		tcf_block_cb_unregister(f->block,
140 					nfp_bpf_setup_tc_block_cb,
141 					nn);
142 		return 0;
143 	default:
144 		return -EOPNOTSUPP;
145 	}
146 }
147 
148 static int nfp_bpf_setup_tc(struct nfp_app *app, struct net_device *netdev,
149 			    enum tc_setup_type type, void *type_data)
150 {
151 	switch (type) {
152 	case TC_SETUP_BLOCK:
153 		return nfp_bpf_setup_tc_block(netdev, type_data);
154 	default:
155 		return -EOPNOTSUPP;
156 	}
157 }
158 
159 static bool nfp_bpf_tc_busy(struct nfp_app *app, struct nfp_net *nn)
160 {
161 	return nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF;
162 }
163 
164 const struct nfp_app_type app_bpf = {
165 	.id		= NFP_APP_BPF_NIC,
166 	.name		= "ebpf",
167 
168 	.extra_cap	= nfp_bpf_extra_cap,
169 
170 	.vnic_alloc	= nfp_app_nic_vnic_alloc,
171 	.vnic_free	= nfp_bpf_vnic_free,
172 
173 	.setup_tc	= nfp_bpf_setup_tc,
174 	.tc_busy	= nfp_bpf_tc_busy,
175 	.xdp_offload	= nfp_bpf_xdp_offload,
176 
177 	.bpf_verifier_prep	= nfp_bpf_verifier_prep,
178 	.bpf_translate		= nfp_bpf_translate,
179 	.bpf_destroy		= nfp_bpf_destroy,
180 };
181