1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * bpf_jit.h: BPF JIT compiler for PPC
4 *
5 * Copyright 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation
6 * 2016 Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
7 */
8 #ifndef _BPF_JIT_H
9 #define _BPF_JIT_H
10
11 #ifndef __ASSEMBLY__
12
13 #include <asm/types.h>
14
15 #ifdef PPC64_ELF_ABI_v1
16 #define FUNCTION_DESCR_SIZE 24
17 #else
18 #define FUNCTION_DESCR_SIZE 0
19 #endif
20
21 /*
22 * 16-bit immediate helper macros: HA() is for use with sign-extending instrs
23 * (e.g. LD, ADDI). If the bottom 16 bits is "-ve", add another bit into the
24 * top half to negate the effect (i.e. 0xffff + 1 = 0x(1)0000).
25 */
26 #define IMM_H(i) ((uintptr_t)(i)>>16)
27 #define IMM_HA(i) (((uintptr_t)(i)>>16) + \
28 (((uintptr_t)(i) & 0x8000) >> 15))
29 #define IMM_L(i) ((uintptr_t)(i) & 0xffff)
30
31 #define PLANT_INSTR(d, idx, instr) \
32 do { if (d) { (d)[idx] = instr; } idx++; } while (0)
33 #define EMIT(instr) PLANT_INSTR(image, ctx->idx, instr)
34
35 #define PPC_NOP() EMIT(PPC_INST_NOP)
36 #define PPC_BLR() EMIT(PPC_INST_BLR)
37 #define PPC_BLRL() EMIT(PPC_INST_BLRL)
38 #define PPC_MTLR(r) EMIT(PPC_INST_MTLR | ___PPC_RT(r))
39 #define PPC_BCTR() EMIT(PPC_INST_BCTR)
40 #define PPC_MTCTR(r) EMIT(PPC_INST_MTCTR | ___PPC_RT(r))
41 #define PPC_ADDI(d, a, i) EMIT(PPC_INST_ADDI | ___PPC_RT(d) | \
42 ___PPC_RA(a) | IMM_L(i))
43 #define PPC_MR(d, a) PPC_OR(d, a, a)
44 #define PPC_LI(r, i) PPC_ADDI(r, 0, i)
45 #define PPC_ADDIS(d, a, i) EMIT(PPC_INST_ADDIS | \
46 ___PPC_RT(d) | ___PPC_RA(a) | IMM_L(i))
47 #define PPC_LIS(r, i) PPC_ADDIS(r, 0, i)
48 #define PPC_STD(r, base, i) EMIT(PPC_INST_STD | ___PPC_RS(r) | \
49 ___PPC_RA(base) | ((i) & 0xfffc))
50 #define PPC_STDX(r, base, b) EMIT(PPC_INST_STDX | ___PPC_RS(r) | \
51 ___PPC_RA(base) | ___PPC_RB(b))
52 #define PPC_STDU(r, base, i) EMIT(PPC_INST_STDU | ___PPC_RS(r) | \
53 ___PPC_RA(base) | ((i) & 0xfffc))
54 #define PPC_STW(r, base, i) EMIT(PPC_INST_STW | ___PPC_RS(r) | \
55 ___PPC_RA(base) | IMM_L(i))
56 #define PPC_STWU(r, base, i) EMIT(PPC_INST_STWU | ___PPC_RS(r) | \
57 ___PPC_RA(base) | IMM_L(i))
58 #define PPC_STH(r, base, i) EMIT(PPC_INST_STH | ___PPC_RS(r) | \
59 ___PPC_RA(base) | IMM_L(i))
60 #define PPC_STB(r, base, i) EMIT(PPC_INST_STB | ___PPC_RS(r) | \
61 ___PPC_RA(base) | IMM_L(i))
62
63 #define PPC_LBZ(r, base, i) EMIT(PPC_INST_LBZ | ___PPC_RT(r) | \
64 ___PPC_RA(base) | IMM_L(i))
65 #define PPC_LD(r, base, i) EMIT(PPC_INST_LD | ___PPC_RT(r) | \
66 ___PPC_RA(base) | ((i) & 0xfffc))
67 #define PPC_LDX(r, base, b) EMIT(PPC_INST_LDX | ___PPC_RT(r) | \
68 ___PPC_RA(base) | ___PPC_RB(b))
69 #define PPC_LWZ(r, base, i) EMIT(PPC_INST_LWZ | ___PPC_RT(r) | \
70 ___PPC_RA(base) | IMM_L(i))
71 #define PPC_LHZ(r, base, i) EMIT(PPC_INST_LHZ | ___PPC_RT(r) | \
72 ___PPC_RA(base) | IMM_L(i))
73 #define PPC_LHBRX(r, base, b) EMIT(PPC_INST_LHBRX | ___PPC_RT(r) | \
74 ___PPC_RA(base) | ___PPC_RB(b))
75 #define PPC_LDBRX(r, base, b) EMIT(PPC_INST_LDBRX | ___PPC_RT(r) | \
76 ___PPC_RA(base) | ___PPC_RB(b))
77
78 #define PPC_BPF_LDARX(t, a, b, eh) EMIT(PPC_INST_LDARX | ___PPC_RT(t) | \
79 ___PPC_RA(a) | ___PPC_RB(b) | \
80 __PPC_EH(eh))
81 #define PPC_BPF_LWARX(t, a, b, eh) EMIT(PPC_INST_LWARX | ___PPC_RT(t) | \
82 ___PPC_RA(a) | ___PPC_RB(b) | \
83 __PPC_EH(eh))
84 #define PPC_BPF_STWCX(s, a, b) EMIT(PPC_INST_STWCX | ___PPC_RS(s) | \
85 ___PPC_RA(a) | ___PPC_RB(b))
86 #define PPC_BPF_STDCX(s, a, b) EMIT(PPC_INST_STDCX | ___PPC_RS(s) | \
87 ___PPC_RA(a) | ___PPC_RB(b))
88 #define PPC_CMPWI(a, i) EMIT(PPC_INST_CMPWI | ___PPC_RA(a) | IMM_L(i))
89 #define PPC_CMPDI(a, i) EMIT(PPC_INST_CMPDI | ___PPC_RA(a) | IMM_L(i))
90 #define PPC_CMPW(a, b) EMIT(PPC_INST_CMPW | ___PPC_RA(a) | \
91 ___PPC_RB(b))
92 #define PPC_CMPD(a, b) EMIT(PPC_INST_CMPD | ___PPC_RA(a) | \
93 ___PPC_RB(b))
94 #define PPC_CMPLWI(a, i) EMIT(PPC_INST_CMPLWI | ___PPC_RA(a) | IMM_L(i))
95 #define PPC_CMPLDI(a, i) EMIT(PPC_INST_CMPLDI | ___PPC_RA(a) | IMM_L(i))
96 #define PPC_CMPLW(a, b) EMIT(PPC_INST_CMPLW | ___PPC_RA(a) | \
97 ___PPC_RB(b))
98 #define PPC_CMPLD(a, b) EMIT(PPC_INST_CMPLD | ___PPC_RA(a) | \
99 ___PPC_RB(b))
100
101 #define PPC_SUB(d, a, b) EMIT(PPC_INST_SUB | ___PPC_RT(d) | \
102 ___PPC_RB(a) | ___PPC_RA(b))
103 #define PPC_ADD(d, a, b) EMIT(PPC_INST_ADD | ___PPC_RT(d) | \
104 ___PPC_RA(a) | ___PPC_RB(b))
105 #define PPC_MULD(d, a, b) EMIT(PPC_INST_MULLD | ___PPC_RT(d) | \
106 ___PPC_RA(a) | ___PPC_RB(b))
107 #define PPC_MULW(d, a, b) EMIT(PPC_INST_MULLW | ___PPC_RT(d) | \
108 ___PPC_RA(a) | ___PPC_RB(b))
109 #define PPC_MULHWU(d, a, b) EMIT(PPC_INST_MULHWU | ___PPC_RT(d) | \
110 ___PPC_RA(a) | ___PPC_RB(b))
111 #define PPC_MULI(d, a, i) EMIT(PPC_INST_MULLI | ___PPC_RT(d) | \
112 ___PPC_RA(a) | IMM_L(i))
113 #define PPC_DIVWU(d, a, b) EMIT(PPC_INST_DIVWU | ___PPC_RT(d) | \
114 ___PPC_RA(a) | ___PPC_RB(b))
115 #define PPC_DIVDU(d, a, b) EMIT(PPC_INST_DIVDU | ___PPC_RT(d) | \
116 ___PPC_RA(a) | ___PPC_RB(b))
117 #define PPC_AND(d, a, b) EMIT(PPC_INST_AND | ___PPC_RA(d) | \
118 ___PPC_RS(a) | ___PPC_RB(b))
119 #define PPC_ANDI(d, a, i) EMIT(PPC_INST_ANDI | ___PPC_RA(d) | \
120 ___PPC_RS(a) | IMM_L(i))
121 #define PPC_AND_DOT(d, a, b) EMIT(PPC_INST_ANDDOT | ___PPC_RA(d) | \
122 ___PPC_RS(a) | ___PPC_RB(b))
123 #define PPC_OR(d, a, b) EMIT(PPC_INST_OR | ___PPC_RA(d) | \
124 ___PPC_RS(a) | ___PPC_RB(b))
125 #define PPC_MR(d, a) PPC_OR(d, a, a)
126 #define PPC_ORI(d, a, i) EMIT(PPC_INST_ORI | ___PPC_RA(d) | \
127 ___PPC_RS(a) | IMM_L(i))
128 #define PPC_ORIS(d, a, i) EMIT(PPC_INST_ORIS | ___PPC_RA(d) | \
129 ___PPC_RS(a) | IMM_L(i))
130 #define PPC_XOR(d, a, b) EMIT(PPC_INST_XOR | ___PPC_RA(d) | \
131 ___PPC_RS(a) | ___PPC_RB(b))
132 #define PPC_XORI(d, a, i) EMIT(PPC_INST_XORI | ___PPC_RA(d) | \
133 ___PPC_RS(a) | IMM_L(i))
134 #define PPC_XORIS(d, a, i) EMIT(PPC_INST_XORIS | ___PPC_RA(d) | \
135 ___PPC_RS(a) | IMM_L(i))
136 #define PPC_EXTSW(d, a) EMIT(PPC_INST_EXTSW | ___PPC_RA(d) | \
137 ___PPC_RS(a))
138 #define PPC_SLW(d, a, s) EMIT(PPC_INST_SLW | ___PPC_RA(d) | \
139 ___PPC_RS(a) | ___PPC_RB(s))
140 #define PPC_SLD(d, a, s) EMIT(PPC_INST_SLD | ___PPC_RA(d) | \
141 ___PPC_RS(a) | ___PPC_RB(s))
142 #define PPC_SRW(d, a, s) EMIT(PPC_INST_SRW | ___PPC_RA(d) | \
143 ___PPC_RS(a) | ___PPC_RB(s))
144 #define PPC_SRAW(d, a, s) EMIT(PPC_INST_SRAW | ___PPC_RA(d) | \
145 ___PPC_RS(a) | ___PPC_RB(s))
146 #define PPC_SRAWI(d, a, i) EMIT(PPC_INST_SRAWI | ___PPC_RA(d) | \
147 ___PPC_RS(a) | __PPC_SH(i))
148 #define PPC_SRD(d, a, s) EMIT(PPC_INST_SRD | ___PPC_RA(d) | \
149 ___PPC_RS(a) | ___PPC_RB(s))
150 #define PPC_SRAD(d, a, s) EMIT(PPC_INST_SRAD | ___PPC_RA(d) | \
151 ___PPC_RS(a) | ___PPC_RB(s))
152 #define PPC_SRADI(d, a, i) EMIT(PPC_INST_SRADI | ___PPC_RA(d) | \
153 ___PPC_RS(a) | __PPC_SH64(i))
154 #define PPC_RLWINM(d, a, i, mb, me) EMIT(PPC_INST_RLWINM | ___PPC_RA(d) | \
155 ___PPC_RS(a) | __PPC_SH(i) | \
156 __PPC_MB(mb) | __PPC_ME(me))
157 #define PPC_RLWINM_DOT(d, a, i, mb, me) EMIT(PPC_INST_RLWINM_DOT | \
158 ___PPC_RA(d) | ___PPC_RS(a) | \
159 __PPC_SH(i) | __PPC_MB(mb) | \
160 __PPC_ME(me))
161 #define PPC_RLWIMI(d, a, i, mb, me) EMIT(PPC_INST_RLWIMI | ___PPC_RA(d) | \
162 ___PPC_RS(a) | __PPC_SH(i) | \
163 __PPC_MB(mb) | __PPC_ME(me))
164 #define PPC_RLDICL(d, a, i, mb) EMIT(PPC_INST_RLDICL | ___PPC_RA(d) | \
165 ___PPC_RS(a) | __PPC_SH64(i) | \
166 __PPC_MB64(mb))
167 #define PPC_RLDICR(d, a, i, me) EMIT(PPC_INST_RLDICR | ___PPC_RA(d) | \
168 ___PPC_RS(a) | __PPC_SH64(i) | \
169 __PPC_ME64(me))
170
171 /* slwi = rlwinm Rx, Ry, n, 0, 31-n */
172 #define PPC_SLWI(d, a, i) PPC_RLWINM(d, a, i, 0, 31-(i))
173 /* srwi = rlwinm Rx, Ry, 32-n, n, 31 */
174 #define PPC_SRWI(d, a, i) PPC_RLWINM(d, a, 32-(i), i, 31)
175 /* sldi = rldicr Rx, Ry, n, 63-n */
176 #define PPC_SLDI(d, a, i) PPC_RLDICR(d, a, i, 63-(i))
177 /* sldi = rldicl Rx, Ry, 64-n, n */
178 #define PPC_SRDI(d, a, i) PPC_RLDICL(d, a, 64-(i), i)
179
180 #define PPC_NEG(d, a) EMIT(PPC_INST_NEG | ___PPC_RT(d) | ___PPC_RA(a))
181
182 /* Long jump; (unconditional 'branch') */
183 #define PPC_JMP(dest) EMIT(PPC_INST_BRANCH | \
184 (((dest) - (ctx->idx * 4)) & 0x03fffffc))
185 /* "cond" here covers BO:BI fields. */
186 #define PPC_BCC_SHORT(cond, dest) EMIT(PPC_INST_BRANCH_COND | \
187 (((cond) & 0x3ff) << 16) | \
188 (((dest) - (ctx->idx * 4)) & \
189 0xfffc))
190 /* Sign-extended 32-bit immediate load */
191 #define PPC_LI32(d, i) do { \
192 if ((int)(uintptr_t)(i) >= -32768 && \
193 (int)(uintptr_t)(i) < 32768) \
194 PPC_LI(d, i); \
195 else { \
196 PPC_LIS(d, IMM_H(i)); \
197 if (IMM_L(i)) \
198 PPC_ORI(d, d, IMM_L(i)); \
199 } } while(0)
200
201 #define PPC_LI64(d, i) do { \
202 if ((long)(i) >= -2147483648 && \
203 (long)(i) < 2147483648) \
204 PPC_LI32(d, i); \
205 else { \
206 if (!((uintptr_t)(i) & 0xffff800000000000ULL)) \
207 PPC_LI(d, ((uintptr_t)(i) >> 32) & 0xffff); \
208 else { \
209 PPC_LIS(d, ((uintptr_t)(i) >> 48)); \
210 if ((uintptr_t)(i) & 0x0000ffff00000000ULL) \
211 PPC_ORI(d, d, \
212 ((uintptr_t)(i) >> 32) & 0xffff); \
213 } \
214 PPC_SLDI(d, d, 32); \
215 if ((uintptr_t)(i) & 0x00000000ffff0000ULL) \
216 PPC_ORIS(d, d, \
217 ((uintptr_t)(i) >> 16) & 0xffff); \
218 if ((uintptr_t)(i) & 0x000000000000ffffULL) \
219 PPC_ORI(d, d, (uintptr_t)(i) & 0xffff); \
220 } } while (0)
221
222 #ifdef CONFIG_PPC64
223 #define PPC_FUNC_ADDR(d,i) do { PPC_LI64(d, i); } while(0)
224 #else
225 #define PPC_FUNC_ADDR(d,i) do { PPC_LI32(d, i); } while(0)
226 #endif
227
is_nearbranch(int offset)228 static inline bool is_nearbranch(int offset)
229 {
230 return (offset < 32768) && (offset >= -32768);
231 }
232
233 /*
234 * The fly in the ointment of code size changing from pass to pass is
235 * avoided by padding the short branch case with a NOP. If code size differs
236 * with different branch reaches we will have the issue of code moving from
237 * one pass to the next and will need a few passes to converge on a stable
238 * state.
239 */
240 #define PPC_BCC(cond, dest) do { \
241 if (is_nearbranch((dest) - (ctx->idx * 4))) { \
242 PPC_BCC_SHORT(cond, dest); \
243 PPC_NOP(); \
244 } else { \
245 /* Flip the 'T or F' bit to invert comparison */ \
246 PPC_BCC_SHORT(cond ^ COND_CMP_TRUE, (ctx->idx+2)*4); \
247 PPC_JMP(dest); \
248 } } while(0)
249
250 /* To create a branch condition, select a bit of cr0... */
251 #define CR0_LT 0
252 #define CR0_GT 1
253 #define CR0_EQ 2
254 /* ...and modify BO[3] */
255 #define COND_CMP_TRUE 0x100
256 #define COND_CMP_FALSE 0x000
257 /* Together, they make all required comparisons: */
258 #define COND_GT (CR0_GT | COND_CMP_TRUE)
259 #define COND_GE (CR0_LT | COND_CMP_FALSE)
260 #define COND_EQ (CR0_EQ | COND_CMP_TRUE)
261 #define COND_NE (CR0_EQ | COND_CMP_FALSE)
262 #define COND_LT (CR0_LT | COND_CMP_TRUE)
263 #define COND_LE (CR0_GT | COND_CMP_FALSE)
264
265 #endif
266
267 #endif
268