aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc/net/bpf_jit32.h
blob: 448dfd4d98e184773968fc7a4b732bbe0877f520 (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
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * bpf_jit32.h: BPF JIT compiler for PPC
 *
 * Copyright 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation
 *
 * Split from bpf_jit.h
 */
#ifndef _BPF_JIT32_H
#define _BPF_JIT32_H

#include <asm/asm-compat.h>
#include "bpf_jit.h"

#ifdef CONFIG_PPC64
#define BPF_PPC_STACK_R3_OFF	48
#define BPF_PPC_STACK_LOCALS	32
#define BPF_PPC_STACK_BASIC	(48+64)
#define BPF_PPC_STACK_SAVE	(18*8)
#define BPF_PPC_STACKFRAME	(BPF_PPC_STACK_BASIC+BPF_PPC_STACK_LOCALS+ \
				 BPF_PPC_STACK_SAVE)
#define BPF_PPC_SLOWPATH_FRAME	(48+64)
#else
#define BPF_PPC_STACK_R3_OFF	24
#define BPF_PPC_STACK_LOCALS	16
#define BPF_PPC_STACK_BASIC	(24+32)
#define BPF_PPC_STACK_SAVE	(18*4)
#define BPF_PPC_STACKFRAME	(BPF_PPC_STACK_BASIC+BPF_PPC_STACK_LOCALS+ \
				 BPF_PPC_STACK_SAVE)
#define BPF_PPC_SLOWPATH_FRAME	(24+32)
#endif

#define REG_SZ         (BITS_PER_LONG/8)

/*
 * Generated code register usage:
 *
 * As normal PPC C ABI (e.g. r1=sp, r2=TOC), with:
 *
 * skb		r3	(Entry parameter)
 * A register	r4
 * X register	r5
 * addr param	r6
 * r7-r10	scratch
 * skb->data	r14
 * skb headlen	r15	(skb->len - skb->data_len)
 * m[0]		r16
 * m[...]	...
 * m[15]	r31
 */
#define r_skb		3
#define r_ret		3
#define r_A		4
#define r_X		5
#define r_addr		6
#define r_scratch1	7
#define r_scratch2	8
#define r_D		14
#define r_HL		15
#define r_M		16

#ifndef __ASSEMBLY__

/*
 * Assembly helpers from arch/powerpc/net/bpf_jit.S:
 */
#define DECLARE_LOAD_FUNC(func)	\
	extern u8 func[], func##_negative_offset[], func##_positive_offset[]

DECLARE_LOAD_FUNC(sk_load_word);
DECLARE_LOAD_FUNC(sk_load_half);
DECLARE_LOAD_FUNC(sk_load_byte);
DECLARE_LOAD_FUNC(sk_load_byte_msh);

#define PPC_LBZ_OFFS(r, base, i) do { if ((i) < 32768) EMIT(PPC_RAW_LBZ(r, base, i));   \
		else {	EMIT(PPC_RAW_ADDIS(r, base, IMM_HA(i)));	      \
			EMIT(PPC_RAW_LBZ(r, r, IMM_L(i))); } } while(0)

#define PPC_LD_OFFS(r, base, i) do { if ((i) < 32768) EMIT(PPC_RAW_LD(r, base, i));     \
		else {	EMIT(PPC_RAW_ADDIS(r, base, IMM_HA(i)));			\
			EMIT(PPC_RAW_LD(r, r, IMM_L(i))); } } while(0)

#define PPC_LWZ_OFFS(r, base, i) do { if ((i) < 32768) EMIT(PPC_RAW_LWZ(r, base, i));   \
		else {	EMIT(PPC_RAW_ADDIS(r, base, IMM_HA(i)));			\
			EMIT(PPC_RAW_LWZ(r, r, IMM_L(i))); } } while(0)

#define PPC_LHZ_OFFS(r, base, i) do { if ((i) < 32768) EMIT(PPC_RAW_LHZ(r, base, i));   \
		else {	EMIT(PPC_RAW_ADDIS(r, base, IMM_HA(i)));			\
			EMIT(PPC_RAW_LHZ(r, r, IMM_L(i))); } } while(0)

#ifdef CONFIG_PPC64
#define PPC_LL_OFFS(r, base, i) do { PPC_LD_OFFS(r, base, i); } while(0)
#else
#define PPC_LL_OFFS(r, base, i) do { PPC_LWZ_OFFS(r, base, i); } while(0)
#endif

#ifdef CONFIG_SMP
#ifdef CONFIG_PPC64
#define PPC_BPF_LOAD_CPU(r)		\
	do { BUILD_BUG_ON(sizeof_field(struct paca_struct, paca_index) != 2);	\
		PPC_LHZ_OFFS(r, 13, offsetof(struct paca_struct, paca_index));	\
	} while (0)
#else
#define PPC_BPF_LOAD_CPU(r)     \
	do { BUILD_BUG_ON(sizeof_field(struct task_struct, cpu) != 4);		\
		PPC_LHZ_OFFS(r, 2, offsetof(struct task_struct, cpu));		\
	} while(0)
#endif
#else
#define PPC_BPF_LOAD_CPU(r) do { EMIT(PPC_RAW_LI(r, 0)); } while(0)
#endif

#define PPC_LHBRX_OFFS(r, base, i) \
		do { PPC_LI32(r, i); EMIT(PPC_RAW_LHBRX(r, r, base)); } while(0)
#ifdef __LITTLE_ENDIAN__
#define PPC_NTOHS_OFFS(r, base, i)	PPC_LHBRX_OFFS(r, base, i)
#else
#define PPC_NTOHS_OFFS(r, base, i)	PPC_LHZ_OFFS(r, base, i)
#endif

#define PPC_BPF_LL(r, base, i) do { EMIT(PPC_RAW_LWZ(r, base, i)); } while(0)
#define PPC_BPF_STL(r, base, i) do { EMIT(PPC_RAW_STW(r, base, i)); } while(0)
#define PPC_BPF_STLU(r, base, i) do { EMIT(PPC_RAW_STWU(r, base, i)); } while(0)

#define SEEN_DATAREF 0x10000 /* might call external helpers */
#define SEEN_XREG    0x20000 /* X reg is used */
#define SEEN_MEM     0x40000 /* SEEN_MEM+(1<<n) = use mem[n] for temporary
			      * storage */
#define SEEN_MEM_MSK 0x0ffff

struct codegen_context {
	unsigned int seen;
	unsigned int idx;
	int pc_ret0; /* bpf index of first RET #0 instruction (if any) */
};

#endif

#endif