xref: /openbmc/linux/arch/openrisc/include/asm/ptrace.h (revision 95c96174)
1 /*
2  * OpenRISC Linux
3  *
4  * Linux architectural port borrowing liberally from similar works of
5  * others.  All original copyrights apply as per the original source
6  * declaration.
7  *
8  * OpenRISC implementation:
9  * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
10  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
11  * et al.
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  */
18 
19 #ifndef __ASM_OPENRISC_PTRACE_H
20 #define __ASM_OPENRISC_PTRACE_H
21 
22 #include <asm/spr_defs.h>
23 
24 #ifndef __ASSEMBLY__
25 /*
26  * This is the layout of the regset returned by the GETREGSET ptrace call
27  */
28 struct user_regs_struct {
29 	/* GPR R0-R31... */
30 	unsigned long gpr[32];
31 	unsigned long pc;
32 	unsigned long sr;
33 	unsigned long pad1;
34 	unsigned long pad2;
35 };
36 #endif
37 
38 #ifdef __KERNEL__
39 
40 /*
41  * Make kernel PTrace/register structures opaque to userspace... userspace can
42  * access thread state via the regset mechanism.  This allows us a bit of
43  * flexibility in how we order the registers on the stack, permitting some
44  * optimizations like packing call-clobbered registers together so that
45  * they share a cacheline (not done yet, though... future optimization).
46  */
47 
48 #ifndef __ASSEMBLY__
49 /*
50  * This struct describes how the registers are laid out on the kernel stack
51  * during a syscall or other kernel entry.
52  *
53  * This structure should always be cacheline aligned on the stack.
54  * FIXME: I don't think that's the case right now.  The alignment is
55  * taken care of elsewhere... head.S, process.c, etc.
56  */
57 
58 struct pt_regs {
59 	union {
60 		struct {
61 			/* Named registers */
62 			long  sr;	/* Stored in place of r0 */
63 			long  sp;	/* r1 */
64 		};
65 		struct {
66 			/* Old style */
67 			long offset[2];
68 			long gprs[30];
69 		};
70 		struct {
71 			/* New style */
72 			long gpr[32];
73 		};
74 	};
75 	long  pc;
76 	/* For restarting system calls:
77 	 * Set to syscall number for syscall exceptions,
78 	 * -1 for all other exceptions.
79 	 */
80 	long  orig_gpr11;	/* For restarting system calls */
81 	long dummy;		/* Cheap alignment fix */
82 	long dummy2;		/* Cheap alignment fix */
83 };
84 
85 /* TODO: Rename this to REDZONE because that's what it is */
86 #define STACK_FRAME_OVERHEAD  128  /* size of minimum stack frame */
87 
88 #define instruction_pointer(regs)	((regs)->pc)
89 #define user_mode(regs)			(((regs)->sr & SPR_SR_SM) == 0)
90 #define user_stack_pointer(regs)	((unsigned long)(regs)->sp)
91 #define profile_pc(regs)		instruction_pointer(regs)
92 
93 static inline long regs_return_value(struct pt_regs *regs)
94 {
95 	return regs->gpr[11];
96 }
97 
98 #endif /* __ASSEMBLY__ */
99 
100 /*
101  * Offsets used by 'ptrace' system call interface.
102  */
103 #define PT_SR         0
104 #define PT_SP         4
105 #define PT_GPR2       8
106 #define PT_GPR3       12
107 #define PT_GPR4       16
108 #define PT_GPR5       20
109 #define PT_GPR6       24
110 #define PT_GPR7       28
111 #define PT_GPR8       32
112 #define PT_GPR9       36
113 #define PT_GPR10      40
114 #define PT_GPR11      44
115 #define PT_GPR12      48
116 #define PT_GPR13      52
117 #define PT_GPR14      56
118 #define PT_GPR15      60
119 #define PT_GPR16      64
120 #define PT_GPR17      68
121 #define PT_GPR18      72
122 #define PT_GPR19      76
123 #define PT_GPR20      80
124 #define PT_GPR21      84
125 #define PT_GPR22      88
126 #define PT_GPR23      92
127 #define PT_GPR24      96
128 #define PT_GPR25      100
129 #define PT_GPR26      104
130 #define PT_GPR27      108
131 #define PT_GPR28      112
132 #define PT_GPR29      116
133 #define PT_GPR30      120
134 #define PT_GPR31      124
135 #define PT_PC	      128
136 #define PT_ORIG_GPR11 132
137 #define PT_SYSCALLNO  136
138 
139 #endif /* __KERNEL__ */
140 
141 #endif /* __ASM_OPENRISC_PTRACE_H */
142