1 /*
2 * Copyright (C) 2016 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 #ifndef __NFP_BPF_H__
35 #define __NFP_BPF_H__ 1
36
37 #include <linux/bitfield.h>
38 #include <linux/bpf.h>
39 #include <linux/list.h>
40 #include <linux/types.h>
41
42 #define FIELD_FIT(mask, val) (!((((u64)val) << __bf_shf(mask)) & ~(mask)))
43
44 /* For branch fixup logic use up-most byte of branch instruction as scratch
45 * area. Remember to clear this before sending instructions to HW!
46 */
47 #define OP_BR_SPECIAL 0xff00000000000000ULL
48
49 enum br_special {
50 OP_BR_NORMAL = 0,
51 OP_BR_GO_OUT,
52 OP_BR_GO_ABORT,
53 };
54
55 enum static_regs {
56 STATIC_REG_PKT = 1,
57 #define REG_PKT_BANK ALU_DST_A
58 STATIC_REG_IMM = 2, /* Bank AB */
59 };
60
61 enum nfp_bpf_action_type {
62 NN_ACT_TC_DROP,
63 NN_ACT_TC_REDIR,
64 NN_ACT_DIRECT,
65 };
66
67 /* Software register representation, hardware encoding in asm.h */
68 #define NN_REG_TYPE GENMASK(31, 24)
69 #define NN_REG_VAL GENMASK(7, 0)
70
71 enum nfp_bpf_reg_type {
72 NN_REG_GPR_A = BIT(0),
73 NN_REG_GPR_B = BIT(1),
74 NN_REG_NNR = BIT(2),
75 NN_REG_XFER = BIT(3),
76 NN_REG_IMM = BIT(4),
77 NN_REG_NONE = BIT(5),
78 };
79
80 #define NN_REG_GPR_BOTH (NN_REG_GPR_A | NN_REG_GPR_B)
81
82 #define reg_both(x) ((x) | FIELD_PREP(NN_REG_TYPE, NN_REG_GPR_BOTH))
83 #define reg_a(x) ((x) | FIELD_PREP(NN_REG_TYPE, NN_REG_GPR_A))
84 #define reg_b(x) ((x) | FIELD_PREP(NN_REG_TYPE, NN_REG_GPR_B))
85 #define reg_nnr(x) ((x) | FIELD_PREP(NN_REG_TYPE, NN_REG_NNR))
86 #define reg_xfer(x) ((x) | FIELD_PREP(NN_REG_TYPE, NN_REG_XFER))
87 #define reg_imm(x) ((x) | FIELD_PREP(NN_REG_TYPE, NN_REG_IMM))
88 #define reg_none() (FIELD_PREP(NN_REG_TYPE, NN_REG_NONE))
89
90 #define pkt_reg(np) reg_a((np)->regs_per_thread - STATIC_REG_PKT)
91 #define imm_a(np) reg_a((np)->regs_per_thread - STATIC_REG_IMM)
92 #define imm_b(np) reg_b((np)->regs_per_thread - STATIC_REG_IMM)
93 #define imm_both(np) reg_both((np)->regs_per_thread - STATIC_REG_IMM)
94
95 #define NFP_BPF_ABI_FLAGS reg_nnr(0)
96 #define NFP_BPF_ABI_FLAG_MARK 1
97 #define NFP_BPF_ABI_MARK reg_nnr(1)
98 #define NFP_BPF_ABI_PKT reg_nnr(2)
99 #define NFP_BPF_ABI_LEN reg_nnr(3)
100
101 struct nfp_prog;
102 struct nfp_insn_meta;
103 typedef int (*instr_cb_t)(struct nfp_prog *, struct nfp_insn_meta *);
104
105 #define nfp_prog_first_meta(nfp_prog) \
106 list_first_entry(&(nfp_prog)->insns, struct nfp_insn_meta, l)
107 #define nfp_prog_last_meta(nfp_prog) \
108 list_last_entry(&(nfp_prog)->insns, struct nfp_insn_meta, l)
109 #define nfp_meta_next(meta) list_next_entry(meta, l)
110 #define nfp_meta_prev(meta) list_prev_entry(meta, l)
111
112 /**
113 * struct nfp_insn_meta - BPF instruction wrapper
114 * @insn: BPF instruction
115 * @off: index of first generated machine instruction (in nfp_prog.prog)
116 * @n: eBPF instruction number
117 * @skip: skip this instruction (optimized out)
118 * @double_cb: callback for second part of the instruction
119 * @l: link on nfp_prog->insns list
120 */
121 struct nfp_insn_meta {
122 struct bpf_insn insn;
123 unsigned int off;
124 unsigned short n;
125 bool skip;
126 instr_cb_t double_cb;
127
128 struct list_head l;
129 };
130
131 #define BPF_SIZE_MASK 0x18
132
mbpf_class(const struct nfp_insn_meta * meta)133 static inline u8 mbpf_class(const struct nfp_insn_meta *meta)
134 {
135 return BPF_CLASS(meta->insn.code);
136 }
137
mbpf_src(const struct nfp_insn_meta * meta)138 static inline u8 mbpf_src(const struct nfp_insn_meta *meta)
139 {
140 return BPF_SRC(meta->insn.code);
141 }
142
mbpf_op(const struct nfp_insn_meta * meta)143 static inline u8 mbpf_op(const struct nfp_insn_meta *meta)
144 {
145 return BPF_OP(meta->insn.code);
146 }
147
mbpf_mode(const struct nfp_insn_meta * meta)148 static inline u8 mbpf_mode(const struct nfp_insn_meta *meta)
149 {
150 return BPF_MODE(meta->insn.code);
151 }
152
153 /**
154 * struct nfp_prog - nfp BPF program
155 * @prog: machine code
156 * @prog_len: number of valid instructions in @prog array
157 * @__prog_alloc_len: alloc size of @prog array
158 * @act: BPF program/action type (TC DA, TC with action, XDP etc.)
159 * @num_regs: number of registers used by this program
160 * @regs_per_thread: number of basic registers allocated per thread
161 * @start_off: address of the first instruction in the memory
162 * @tgt_out: jump target for normal exit
163 * @tgt_abort: jump target for abort (e.g. access outside of packet buffer)
164 * @tgt_done: jump target to get the next packet
165 * @n_translated: number of successfully translated instructions (for errors)
166 * @error: error code if something went wrong
167 * @insns: list of BPF instruction wrappers (struct nfp_insn_meta)
168 */
169 struct nfp_prog {
170 u64 *prog;
171 unsigned int prog_len;
172 unsigned int __prog_alloc_len;
173
174 enum nfp_bpf_action_type act;
175
176 unsigned int num_regs;
177 unsigned int regs_per_thread;
178
179 unsigned int start_off;
180 unsigned int tgt_out;
181 unsigned int tgt_abort;
182 unsigned int tgt_done;
183
184 unsigned int n_translated;
185 int error;
186
187 struct list_head insns;
188 };
189
190 struct nfp_bpf_result {
191 unsigned int n_instr;
192 bool dense_mode;
193 };
194
195 int
196 nfp_bpf_jit(struct bpf_prog *filter, void *prog, enum nfp_bpf_action_type act,
197 unsigned int prog_start, unsigned int prog_done,
198 unsigned int prog_sz, struct nfp_bpf_result *res);
199
200 int nfp_prog_verify(struct nfp_prog *nfp_prog, struct bpf_prog *prog);
201
202 #endif
203