summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/net/bpf_jit.h
blob: 55d4377ccfae3fe98555b7076b2cca12178afdff (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * bpf_jit.h: BPF JIT compiler for PPC
 *
 * Copyright 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation
 * 	     2016 Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
 */
#ifndef _BPF_JIT_H
#define _BPF_JIT_H

#ifndef __ASSEMBLY__

#include <asm/types.h>

#ifdef PPC64_ELF_ABI_v1
#define FUNCTION_DESCR_SIZE	24
#else
#define FUNCTION_DESCR_SIZE	0
#endif

/*
 * 16-bit immediate helper macros: HA() is for use with sign-extending instrs
 * (e.g. LD, ADDI).  If the bottom 16 bits is "-ve", add another bit into the
 * top half to negate the effect (i.e. 0xffff + 1 = 0x(1)0000).
 */
#define IMM_H(i)		((uintptr_t)(i)>>16)
#define IMM_HA(i)		(((uintptr_t)(i)>>16) +			      \
					(((uintptr_t)(i) & 0x8000) >> 15))
#define IMM_L(i)		((uintptr_t)(i) & 0xffff)

#define PLANT_INSTR(d, idx, instr)					      \
	do { if (d) { (d)[idx] = instr; } idx++; } while (0)
#define EMIT(instr)		PLANT_INSTR(image, ctx->idx, instr)

#define PPC_NOP()		EMIT(PPC_INST_NOP)
#define PPC_BLR()		EMIT(PPC_INST_BLR)
#define PPC_BLRL()		EMIT(PPC_INST_BLRL)
#define PPC_MTLR(r)		EMIT(PPC_INST_MTLR | ___PPC_RT(r))
#define PPC_BCTR()		EMIT(PPC_INST_BCTR)
#define PPC_MTCTR(r)		EMIT(PPC_INST_MTCTR | ___PPC_RT(r))
#define PPC_ADDI(d, a, i)	EMIT(PPC_INST_ADDI | ___PPC_RT(d) |	      \
				     ___PPC_RA(a) | IMM_L(i))
#define PPC_MR(d, a)		PPC_OR(d, a, a)
#define PPC_LI(r, i)		PPC_ADDI(r, 0, i)
#define PPC_ADDIS(d, a, i)	EMIT(PPC_INST_ADDIS |			      \
				     ___PPC_RT(d) | ___PPC_RA(a) | IMM_L(i))
#define PPC_LIS(r, i)		PPC_ADDIS(r, 0, i)
#define PPC_STD(r, base, i)	EMIT(PPC_INST_STD | ___PPC_RS(r) |	      \
				     ___PPC_RA(base) | ((i) & 0xfffc))
#define PPC_STDX(r, base, b)	EMIT(PPC_INST_STDX | ___PPC_RS(r) |	      \
				     ___PPC_RA(base) | ___PPC_RB(b))
#define PPC_STDU(r, base, i)	EMIT(PPC_INST_STDU | ___PPC_RS(r) |	      \
				     ___PPC_RA(base) | ((i) & 0xfffc))
#define PPC_STW(r, base, i)	EMIT(PPC_INST_STW | ___PPC_RS(r) |	      \
				     ___PPC_RA(base) | IMM_L(i))
#define PPC_STWU(r, base, i)	EMIT(PPC_INST_STWU | ___PPC_RS(r) |	      \
				     ___PPC_RA(base) | IMM_L(i))
#define PPC_STH(r, base, i)	EMIT(PPC_INST_STH | ___PPC_RS(r) |	      \
				     ___PPC_RA(base) | IMM_L(i))
#define PPC_STB(r, base, i)	EMIT(PPC_INST_STB | ___PPC_RS(r) |	      \
				     ___PPC_RA(base) | IMM_L(i))

#define PPC_LBZ(r, base, i)	EMIT(PPC_INST_LBZ | ___PPC_RT(r) |	      \
				     ___PPC_RA(base) | IMM_L(i))
#define PPC_LD(r, base, i)	EMIT(PPC_INST_LD | ___PPC_RT(r) |	      \
				     ___PPC_RA(base) | ((i) & 0xfffc))
#define PPC_LDX(r, base, b)	EMIT(PPC_INST_LDX | ___PPC_RT(r) |	      \
				     ___PPC_RA(base) | ___PPC_RB(b))
#define PPC_LWZ(r, base, i)	EMIT(PPC_INST_LWZ | ___PPC_RT(r) |	      \
				     ___PPC_RA(base) | IMM_L(i))
#define PPC_LHZ(r, base, i)	EMIT(PPC_INST_LHZ | ___PPC_RT(r) |	      \
				     ___PPC_RA(base) | IMM_L(i))
#define PPC_LHBRX(r, base, b)	EMIT(PPC_INST_LHBRX | ___PPC_RT(r) |	      \
				     ___PPC_RA(base) | ___PPC_RB(b))
#define PPC_LDBRX(r, base, b)	EMIT(PPC_INST_LDBRX | ___PPC_RT(r) |	      \
				     ___PPC_RA(base) | ___PPC_RB(b))

#define PPC_BPF_LDARX(t, a, b, eh) EMIT(PPC_INST_LDARX | ___PPC_RT(t) |	      \
					___PPC_RA(a) | ___PPC_RB(b) |	      \
					__PPC_EH(eh))
#define PPC_BPF_LWARX(t, a, b, eh) EMIT(PPC_INST_LWARX | ___PPC_RT(t) |	      \
					___PPC_RA(a) | ___PPC_RB(b) |	      \
					__PPC_EH(eh))
#define PPC_BPF_STWCX(s, a, b)	EMIT(PPC_INST_STWCX | ___PPC_RS(s) |	      \
					___PPC_RA(a) | ___PPC_RB(b))
#define PPC_BPF_STDCX(s, a, b)	EMIT(PPC_INST_STDCX | ___PPC_RS(s) |	      \
					___PPC_RA(a) | ___PPC_RB(b))
#define PPC_CMPWI(a, i)		EMIT(PPC_INST_CMPWI | ___PPC_RA(a) | IMM_L(i))
#define PPC_CMPDI(a, i)		EMIT(PPC_INST_CMPDI | ___PPC_RA(a) | IMM_L(i))
#define PPC_CMPW(a, b)		EMIT(PPC_INST_CMPW | ___PPC_RA(a) |	      \
					___PPC_RB(b))
#define PPC_CMPD(a, b)		EMIT(PPC_INST_CMPD | ___PPC_RA(a) |	      \
					___PPC_RB(b))
#define PPC_CMPLWI(a, i)	EMIT(PPC_INST_CMPLWI | ___PPC_RA(a) | IMM_L(i))
#define PPC_CMPLDI(a, i)	EMIT(PPC_INST_CMPLDI | ___PPC_RA(a) | IMM_L(i))
#define PPC_CMPLW(a, b)		EMIT(PPC_INST_CMPLW | ___PPC_RA(a) |	      \
					___PPC_RB(b))
#define PPC_CMPLD(a, b)		EMIT(PPC_INST_CMPLD | ___PPC_RA(a) |	      \
					___PPC_RB(b))

#define PPC_SUB(d, a, b)	EMIT(PPC_INST_SUB | ___PPC_RT(d) |	      \
				     ___PPC_RB(a) | ___PPC_RA(b))
#define PPC_ADD(d, a, b)	EMIT(PPC_INST_ADD | ___PPC_RT(d) |	      \
				     ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_MULD(d, a, b)	EMIT(PPC_INST_MULLD | ___PPC_RT(d) |	      \
				     ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_MULW(d, a, b)	EMIT(PPC_INST_MULLW | ___PPC_RT(d) |	      \
				     ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_MULHWU(d, a, b)	EMIT(PPC_INST_MULHWU | ___PPC_RT(d) |	      \
				     ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_MULI(d, a, i)	EMIT(PPC_INST_MULLI | ___PPC_RT(d) |	      \
				     ___PPC_RA(a) | IMM_L(i))
#define PPC_DIVWU(d, a, b)	EMIT(PPC_INST_DIVWU | ___PPC_RT(d) |	      \
				     ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_DIVDU(d, a, b)	EMIT(PPC_INST_DIVDU | ___PPC_RT(d) |	      \
				     ___PPC_RA(a) | ___PPC_RB(b))
#define PPC_AND(d, a, b)	EMIT(PPC_INST_AND | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | ___PPC_RB(b))
#define PPC_ANDI(d, a, i)	EMIT(PPC_INST_ANDI | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | IMM_L(i))
#define PPC_AND_DOT(d, a, b)	EMIT(PPC_INST_ANDDOT | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | ___PPC_RB(b))
#define PPC_OR(d, a, b)		EMIT(PPC_INST_OR | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | ___PPC_RB(b))
#define PPC_MR(d, a)		PPC_OR(d, a, a)
#define PPC_ORI(d, a, i)	EMIT(PPC_INST_ORI | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | IMM_L(i))
#define PPC_ORIS(d, a, i)	EMIT(PPC_INST_ORIS | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | IMM_L(i))
#define PPC_XOR(d, a, b)	EMIT(PPC_INST_XOR | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | ___PPC_RB(b))
#define PPC_XORI(d, a, i)	EMIT(PPC_INST_XORI | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | IMM_L(i))
#define PPC_XORIS(d, a, i)	EMIT(PPC_INST_XORIS | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | IMM_L(i))
#define PPC_EXTSW(d, a)		EMIT(PPC_INST_EXTSW | ___PPC_RA(d) |	      \
				     ___PPC_RS(a))
#define PPC_SLW(d, a, s)	EMIT(PPC_INST_SLW | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | ___PPC_RB(s))
#define PPC_SLD(d, a, s)	EMIT(PPC_INST_SLD | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | ___PPC_RB(s))
#define PPC_SRW(d, a, s)	EMIT(PPC_INST_SRW | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | ___PPC_RB(s))
#define PPC_SRAW(d, a, s)	EMIT(PPC_INST_SRAW | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | ___PPC_RB(s))
#define PPC_SRAWI(d, a, i)	EMIT(PPC_INST_SRAWI | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | __PPC_SH(i))
#define PPC_SRD(d, a, s)	EMIT(PPC_INST_SRD | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | ___PPC_RB(s))
#define PPC_SRAD(d, a, s)	EMIT(PPC_INST_SRAD | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | ___PPC_RB(s))
#define PPC_SRADI(d, a, i)	EMIT(PPC_INST_SRADI | ___PPC_RA(d) |	      \
				     ___PPC_RS(a) | __PPC_SH64(i))
#define PPC_RLWINM(d, a, i, mb, me)	EMIT(PPC_INST_RLWINM | ___PPC_RA(d) | \
					___PPC_RS(a) | __PPC_SH(i) |	      \
					__PPC_MB(mb) | __PPC_ME(me))
#define PPC_RLWINM_DOT(d, a, i, mb, me)	EMIT(PPC_INST_RLWINM_DOT |	      \
					___PPC_RA(d) | ___PPC_RS(a) |	      \
					__PPC_SH(i) | __PPC_MB(mb) |	      \
					__PPC_ME(me))
#define PPC_RLWIMI(d, a, i, mb, me)	EMIT(PPC_INST_RLWIMI | ___PPC_RA(d) | \
					___PPC_RS(a) | __PPC_SH(i) |	      \
					__PPC_MB(mb) | __PPC_ME(me))
#define PPC_RLDICL(d, a, i, mb)		EMIT(PPC_INST_RLDICL | ___PPC_RA(d) | \
					___PPC_RS(a) | __PPC_SH64(i) |	      \
					__PPC_MB64(mb))
#define PPC_RLDICR(d, a, i, me)		EMIT(PPC_INST_RLDICR | ___PPC_RA(d) | \
					___PPC_RS(a) | __PPC_SH64(i) |	      \
					__PPC_ME64(me))

/* slwi = rlwinm Rx, Ry, n, 0, 31-n */
#define PPC_SLWI(d, a, i)	PPC_RLWINM(d, a, i, 0, 31-(i))
/* srwi = rlwinm Rx, Ry, 32-n, n, 31 */
#define PPC_SRWI(d, a, i)	PPC_RLWINM(d, a, 32-(i), i, 31)
/* sldi = rldicr Rx, Ry, n, 63-n */
#define PPC_SLDI(d, a, i)	PPC_RLDICR(d, a, i, 63-(i))
/* sldi = rldicl Rx, Ry, 64-n, n */
#define PPC_SRDI(d, a, i)	PPC_RLDICL(d, a, 64-(i), i)

#define PPC_NEG(d, a)		EMIT(PPC_INST_NEG | ___PPC_RT(d) | ___PPC_RA(a))

/* Long jump; (unconditional 'branch') */
#define PPC_JMP(dest)		EMIT(PPC_INST_BRANCH |			      \
				     (((dest) - (ctx->idx * 4)) & 0x03fffffc))
/* "cond" here covers BO:BI fields. */
#define PPC_BCC_SHORT(cond, dest)	EMIT(PPC_INST_BRANCH_COND |	      \
					     (((cond) & 0x3ff) << 16) |	      \
					     (((dest) - (ctx->idx * 4)) &     \
					      0xfffc))
/* Sign-extended 32-bit immediate load */
#define PPC_LI32(d, i)		do {					      \
		if ((int)(uintptr_t)(i) >= -32768 &&			      \
				(int)(uintptr_t)(i) < 32768)		      \
			PPC_LI(d, i);					      \
		else {							      \
			PPC_LIS(d, IMM_H(i));				      \
			if (IMM_L(i))					      \
				PPC_ORI(d, d, IMM_L(i));		      \
		} } while(0)

#define PPC_LI64(d, i)		do {					      \
		if ((long)(i) >= -2147483648 &&				      \
				(long)(i) < 2147483648)			      \
			PPC_LI32(d, i);					      \
		else {							      \
			if (!((uintptr_t)(i) & 0xffff800000000000ULL))	      \
				PPC_LI(d, ((uintptr_t)(i) >> 32) & 0xffff);   \
			else {						      \
				PPC_LIS(d, ((uintptr_t)(i) >> 48));	      \
				if ((uintptr_t)(i) & 0x0000ffff00000000ULL)   \
					PPC_ORI(d, d,			      \
					  ((uintptr_t)(i) >> 32) & 0xffff);   \
			}						      \
			PPC_SLDI(d, d, 32);				      \
			if ((uintptr_t)(i) & 0x00000000ffff0000ULL)	      \
				PPC_ORIS(d, d,				      \
					 ((uintptr_t)(i) >> 16) & 0xffff);    \
			if ((uintptr_t)(i) & 0x000000000000ffffULL)	      \
				PPC_ORI(d, d, (uintptr_t)(i) & 0xffff);	      \
		} } while (0)

#ifdef CONFIG_PPC64
#define PPC_FUNC_ADDR(d,i) do { PPC_LI64(d, i); } while(0)
#else
#define PPC_FUNC_ADDR(d,i) do { PPC_LI32(d, i); } while(0)
#endif

static inline bool is_nearbranch(int offset)
{
	return (offset < 32768) && (offset >= -32768);
}

/*
 * The fly in the ointment of code size changing from pass to pass is
 * avoided by padding the short branch case with a NOP.	 If code size differs
 * with different branch reaches we will have the issue of code moving from
 * one pass to the next and will need a few passes to converge on a stable
 * state.
 */
#define PPC_BCC(cond, dest)	do {					      \
		if (is_nearbranch((dest) - (ctx->idx * 4))) {		      \
			PPC_BCC_SHORT(cond, dest);			      \
			PPC_NOP();					      \
		} else {						      \
			/* Flip the 'T or F' bit to invert comparison */      \
			PPC_BCC_SHORT(cond ^ COND_CMP_TRUE, (ctx->idx+2)*4);  \
			PPC_JMP(dest);					      \
		} } while(0)

/* To create a branch condition, select a bit of cr0... */
#define CR0_LT		0
#define CR0_GT		1
#define CR0_EQ		2
/* ...and modify BO[3] */
#define COND_CMP_TRUE	0x100
#define COND_CMP_FALSE	0x000
/* Together, they make all required comparisons: */
#define COND_GT		(CR0_GT | COND_CMP_TRUE)
#define COND_GE		(CR0_LT | COND_CMP_FALSE)
#define COND_EQ		(CR0_EQ | COND_CMP_TRUE)
#define COND_NE		(CR0_EQ | COND_CMP_FALSE)
#define COND_LT		(CR0_LT | COND_CMP_TRUE)
#define COND_LE		(CR0_GT | COND_CMP_FALSE)

#endif

#endif