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Linux kernel mirror (for testing)
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linux
1/*
2 * Copyright (C) 2001 PPC64 Team, IBM Corp
3 *
4 * This struct defines the way the registers are stored on the
5 * kernel stack during a system call or other kernel entry.
6 *
7 * this should only contain volatile regs
8 * since we can keep non-volatile in the thread_struct
9 * should set this up when only volatiles are saved
10 * by intr code.
11 *
12 * Since this is going on the stack, *CARE MUST BE TAKEN* to insure
13 * that the overall structure is a multiple of 16 bytes in length.
14 *
15 * Note that the offsets of the fields in this struct correspond with
16 * the PT_* values below. This simplifies arch/powerpc/kernel/ptrace.c.
17 *
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License
20 * as published by the Free Software Foundation; either version
21 * 2 of the License, or (at your option) any later version.
22 */
23#ifndef _ASM_POWERPC_PTRACE_H
24#define _ASM_POWERPC_PTRACE_H
25
26#include <uapi/asm/ptrace.h>
27
28
29#ifdef __powerpc64__
30
31#define STACK_FRAME_OVERHEAD 112 /* size of minimum stack frame */
32#define STACK_FRAME_LR_SAVE 2 /* Location of LR in stack frame */
33#define STACK_FRAME_REGS_MARKER ASM_CONST(0x7265677368657265)
34#define STACK_INT_FRAME_SIZE (sizeof(struct pt_regs) + \
35 STACK_FRAME_OVERHEAD + 288)
36#define STACK_FRAME_MARKER 12
37
38/* Size of dummy stack frame allocated when calling signal handler. */
39#define __SIGNAL_FRAMESIZE 128
40#define __SIGNAL_FRAMESIZE32 64
41
42#else /* __powerpc64__ */
43
44#define STACK_FRAME_OVERHEAD 16 /* size of minimum stack frame */
45#define STACK_FRAME_LR_SAVE 1 /* Location of LR in stack frame */
46#define STACK_FRAME_REGS_MARKER ASM_CONST(0x72656773)
47#define STACK_INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD)
48#define STACK_FRAME_MARKER 2
49
50/* Size of stack frame allocated when calling signal handler. */
51#define __SIGNAL_FRAMESIZE 64
52
53#endif /* __powerpc64__ */
54
55#ifndef __ASSEMBLY__
56
57#define GET_IP(regs) ((regs)->nip)
58#define GET_USP(regs) ((regs)->gpr[1])
59#define GET_FP(regs) (0)
60#define SET_FP(regs, val)
61
62#ifdef CONFIG_SMP
63extern unsigned long profile_pc(struct pt_regs *regs);
64#define profile_pc profile_pc
65#endif
66
67#include <asm-generic/ptrace.h>
68
69#define kernel_stack_pointer(regs) ((regs)->gpr[1])
70static inline int is_syscall_success(struct pt_regs *regs)
71{
72 return !(regs->ccr & 0x10000000);
73}
74
75static inline long regs_return_value(struct pt_regs *regs)
76{
77 if (is_syscall_success(regs))
78 return regs->gpr[3];
79 else
80 return -regs->gpr[3];
81}
82
83#ifdef __powerpc64__
84#define user_mode(regs) ((((regs)->msr) >> MSR_PR_LG) & 0x1)
85#else
86#define user_mode(regs) (((regs)->msr & MSR_PR) != 0)
87#endif
88
89#define force_successful_syscall_return() \
90 do { \
91 set_thread_flag(TIF_NOERROR); \
92 } while(0)
93
94struct task_struct;
95extern unsigned long ptrace_get_reg(struct task_struct *task, int regno);
96extern int ptrace_put_reg(struct task_struct *task, int regno,
97 unsigned long data);
98
99#define current_pt_regs() \
100 ((struct pt_regs *)((unsigned long)current_thread_info() + THREAD_SIZE) - 1)
101/*
102 * We use the least-significant bit of the trap field to indicate
103 * whether we have saved the full set of registers, or only a
104 * partial set. A 1 there means the partial set.
105 * On 4xx we use the next bit to indicate whether the exception
106 * is a critical exception (1 means it is).
107 */
108#define FULL_REGS(regs) (((regs)->trap & 1) == 0)
109#ifndef __powerpc64__
110#define IS_CRITICAL_EXC(regs) (((regs)->trap & 2) != 0)
111#define IS_MCHECK_EXC(regs) (((regs)->trap & 4) != 0)
112#define IS_DEBUG_EXC(regs) (((regs)->trap & 8) != 0)
113#endif /* ! __powerpc64__ */
114#define TRAP(regs) ((regs)->trap & ~0xF)
115#ifdef __powerpc64__
116#define NV_REG_POISON 0xdeadbeefdeadbeefUL
117#define CHECK_FULL_REGS(regs) BUG_ON(regs->trap & 1)
118#else
119#define NV_REG_POISON 0xdeadbeef
120#define CHECK_FULL_REGS(regs) \
121do { \
122 if ((regs)->trap & 1) \
123 printk(KERN_CRIT "%s: partial register set\n", __func__); \
124} while (0)
125#endif /* __powerpc64__ */
126
127#define arch_has_single_step() (1)
128#define arch_has_block_step() (!cpu_has_feature(CPU_FTR_601))
129#define ARCH_HAS_USER_SINGLE_STEP_INFO
130
131/*
132 * kprobe-based event tracer support
133 */
134
135#include <linux/stddef.h>
136#include <linux/thread_info.h>
137extern int regs_query_register_offset(const char *name);
138extern const char *regs_query_register_name(unsigned int offset);
139#define MAX_REG_OFFSET (offsetof(struct pt_regs, dsisr))
140
141/**
142 * regs_get_register() - get register value from its offset
143 * @regs: pt_regs from which register value is gotten
144 * @offset: offset number of the register.
145 *
146 * regs_get_register returns the value of a register whose offset from @regs.
147 * The @offset is the offset of the register in struct pt_regs.
148 * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
149 */
150static inline unsigned long regs_get_register(struct pt_regs *regs,
151 unsigned int offset)
152{
153 if (unlikely(offset > MAX_REG_OFFSET))
154 return 0;
155 return *(unsigned long *)((unsigned long)regs + offset);
156}
157
158/**
159 * regs_within_kernel_stack() - check the address in the stack
160 * @regs: pt_regs which contains kernel stack pointer.
161 * @addr: address which is checked.
162 *
163 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
164 * If @addr is within the kernel stack, it returns true. If not, returns false.
165 */
166
167static inline bool regs_within_kernel_stack(struct pt_regs *regs,
168 unsigned long addr)
169{
170 return ((addr & ~(THREAD_SIZE - 1)) ==
171 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
172}
173
174/**
175 * regs_get_kernel_stack_nth() - get Nth entry of the stack
176 * @regs: pt_regs which contains kernel stack pointer.
177 * @n: stack entry number.
178 *
179 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
180 * is specified by @regs. If the @n th entry is NOT in the kernel stack,
181 * this returns 0.
182 */
183static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
184 unsigned int n)
185{
186 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
187 addr += n;
188 if (regs_within_kernel_stack(regs, (unsigned long)addr))
189 return *addr;
190 else
191 return 0;
192}
193
194#endif /* __ASSEMBLY__ */
195
196#ifndef __powerpc64__
197#else /* __powerpc64__ */
198#define PT_FPSCR32 (PT_FPR0 + 2*32 + 1) /* each FP reg occupies 2 32-bit userspace slots */
199#define PT_VR0_32 164 /* each Vector reg occupies 4 slots in 32-bit */
200#define PT_VSCR_32 (PT_VR0 + 32*4 + 3)
201#define PT_VRSAVE_32 (PT_VR0 + 33*4)
202#define PT_VSR0_32 300 /* each VSR reg occupies 4 slots in 32-bit */
203#endif /* __powerpc64__ */
204#endif /* _ASM_POWERPC_PTRACE_H */