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 63 extern 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]) 70 static inline int is_syscall_success(struct pt_regs *regs) 71 { 72 return !(regs->ccr & 0x10000000); 73 } 74 75 static 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 94 struct task_struct; 95 extern int ptrace_get_reg(struct task_struct *task, int regno, 96 unsigned long *data); 97 extern int ptrace_put_reg(struct task_struct *task, int regno, 98 unsigned long data); 99 100 #define current_pt_regs() \ 101 ((struct pt_regs *)((unsigned long)current_thread_info() + THREAD_SIZE) - 1) 102 /* 103 * We use the least-significant bit of the trap field to indicate 104 * whether we have saved the full set of registers, or only a 105 * partial set. A 1 there means the partial set. 106 * On 4xx we use the next bit to indicate whether the exception 107 * is a critical exception (1 means it is). 108 */ 109 #define FULL_REGS(regs) (((regs)->trap & 1) == 0) 110 #ifndef __powerpc64__ 111 #define IS_CRITICAL_EXC(regs) (((regs)->trap & 2) != 0) 112 #define IS_MCHECK_EXC(regs) (((regs)->trap & 4) != 0) 113 #define IS_DEBUG_EXC(regs) (((regs)->trap & 8) != 0) 114 #endif /* ! __powerpc64__ */ 115 #define TRAP(regs) ((regs)->trap & ~0xF) 116 #ifdef __powerpc64__ 117 #define NV_REG_POISON 0xdeadbeefdeadbeefUL 118 #define CHECK_FULL_REGS(regs) BUG_ON(regs->trap & 1) 119 #else 120 #define NV_REG_POISON 0xdeadbeef 121 #define CHECK_FULL_REGS(regs) \ 122 do { \ 123 if ((regs)->trap & 1) \ 124 printk(KERN_CRIT "%s: partial register set\n", __func__); \ 125 } while (0) 126 #endif /* __powerpc64__ */ 127 128 #define arch_has_single_step() (1) 129 #define arch_has_block_step() (!cpu_has_feature(CPU_FTR_601)) 130 #define ARCH_HAS_USER_SINGLE_STEP_INFO 131 132 /* 133 * kprobe-based event tracer support 134 */ 135 136 #include <linux/stddef.h> 137 #include <linux/thread_info.h> 138 extern int regs_query_register_offset(const char *name); 139 extern const char *regs_query_register_name(unsigned int offset); 140 #define MAX_REG_OFFSET (offsetof(struct pt_regs, dsisr)) 141 142 /** 143 * regs_get_register() - get register value from its offset 144 * @regs: pt_regs from which register value is gotten 145 * @offset: offset number of the register. 146 * 147 * regs_get_register returns the value of a register whose offset from @regs. 148 * The @offset is the offset of the register in struct pt_regs. 149 * If @offset is bigger than MAX_REG_OFFSET, this returns 0. 150 */ 151 static inline unsigned long regs_get_register(struct pt_regs *regs, 152 unsigned int offset) 153 { 154 if (unlikely(offset > MAX_REG_OFFSET)) 155 return 0; 156 return *(unsigned long *)((unsigned long)regs + offset); 157 } 158 159 /** 160 * regs_within_kernel_stack() - check the address in the stack 161 * @regs: pt_regs which contains kernel stack pointer. 162 * @addr: address which is checked. 163 * 164 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s). 165 * If @addr is within the kernel stack, it returns true. If not, returns false. 166 */ 167 168 static inline bool regs_within_kernel_stack(struct pt_regs *regs, 169 unsigned long addr) 170 { 171 return ((addr & ~(THREAD_SIZE - 1)) == 172 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))); 173 } 174 175 /** 176 * regs_get_kernel_stack_nth() - get Nth entry of the stack 177 * @regs: pt_regs which contains kernel stack pointer. 178 * @n: stack entry number. 179 * 180 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which 181 * is specified by @regs. If the @n th entry is NOT in the kernel stack, 182 * this returns 0. 183 */ 184 static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, 185 unsigned int n) 186 { 187 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs); 188 addr += n; 189 if (regs_within_kernel_stack(regs, (unsigned long)addr)) 190 return *addr; 191 else 192 return 0; 193 } 194 195 #endif /* __ASSEMBLY__ */ 196 197 #ifndef __powerpc64__ 198 #else /* __powerpc64__ */ 199 #define PT_FPSCR32 (PT_FPR0 + 2*32 + 1) /* each FP reg occupies 2 32-bit userspace slots */ 200 #define PT_VR0_32 164 /* each Vector reg occupies 4 slots in 32-bit */ 201 #define PT_VSCR_32 (PT_VR0 + 32*4 + 3) 202 #define PT_VRSAVE_32 (PT_VR0 + 33*4) 203 #define PT_VSR0_32 300 /* each VSR reg occupies 4 slots in 32-bit */ 204 #endif /* __powerpc64__ */ 205 #endif /* _ASM_POWERPC_PTRACE_H */ 206