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 #include <asm/asm-const.h> 28 29 #ifndef __ASSEMBLY__ 30 struct pt_regs 31 { 32 union { 33 struct user_pt_regs user_regs; 34 struct { 35 unsigned long gpr[32]; 36 unsigned long nip; 37 unsigned long msr; 38 unsigned long orig_gpr3; 39 unsigned long ctr; 40 unsigned long link; 41 unsigned long xer; 42 unsigned long ccr; 43 #ifdef CONFIG_PPC64 44 unsigned long softe; 45 #else 46 unsigned long mq; 47 #endif 48 unsigned long trap; 49 unsigned long dar; 50 unsigned long dsisr; 51 unsigned long result; 52 }; 53 }; 54 55 union { 56 struct { 57 #ifdef CONFIG_PPC64 58 unsigned long ppr; 59 #endif 60 #ifdef CONFIG_PPC_KUAP 61 unsigned long kuap; 62 #endif 63 }; 64 unsigned long __pad[2]; /* Maintain 16 byte interrupt stack alignment */ 65 }; 66 }; 67 #endif 68 69 #ifdef __powerpc64__ 70 71 /* 72 * Size of redzone that userspace is allowed to use below the stack 73 * pointer. This is 288 in the 64-bit big-endian ELF ABI, and 512 in 74 * the new ELFv2 little-endian ABI, so we allow the larger amount. 75 * 76 * For kernel code we allow a 288-byte redzone, in order to conserve 77 * kernel stack space; gcc currently only uses 288 bytes, and will 78 * hopefully allow explicit control of the redzone size in future. 79 */ 80 #define USER_REDZONE_SIZE 512 81 #define KERNEL_REDZONE_SIZE 288 82 83 #define STACK_FRAME_OVERHEAD 112 /* size of minimum stack frame */ 84 #define STACK_FRAME_LR_SAVE 2 /* Location of LR in stack frame */ 85 #define STACK_FRAME_REGS_MARKER ASM_CONST(0x7265677368657265) 86 #define STACK_INT_FRAME_SIZE (sizeof(struct pt_regs) + \ 87 STACK_FRAME_OVERHEAD + KERNEL_REDZONE_SIZE) 88 #define STACK_FRAME_MARKER 12 89 90 #ifdef PPC64_ELF_ABI_v2 91 #define STACK_FRAME_MIN_SIZE 32 92 #else 93 #define STACK_FRAME_MIN_SIZE STACK_FRAME_OVERHEAD 94 #endif 95 96 /* Size of dummy stack frame allocated when calling signal handler. */ 97 #define __SIGNAL_FRAMESIZE 128 98 #define __SIGNAL_FRAMESIZE32 64 99 100 #else /* __powerpc64__ */ 101 102 #define USER_REDZONE_SIZE 0 103 #define KERNEL_REDZONE_SIZE 0 104 #define STACK_FRAME_OVERHEAD 16 /* size of minimum stack frame */ 105 #define STACK_FRAME_LR_SAVE 1 /* Location of LR in stack frame */ 106 #define STACK_FRAME_REGS_MARKER ASM_CONST(0x72656773) 107 #define STACK_INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD) 108 #define STACK_FRAME_MARKER 2 109 #define STACK_FRAME_MIN_SIZE STACK_FRAME_OVERHEAD 110 111 /* Size of stack frame allocated when calling signal handler. */ 112 #define __SIGNAL_FRAMESIZE 64 113 114 #endif /* __powerpc64__ */ 115 116 #ifndef __ASSEMBLY__ 117 118 #define GET_IP(regs) ((regs)->nip) 119 #define GET_USP(regs) ((regs)->gpr[1]) 120 #define GET_FP(regs) (0) 121 #define SET_FP(regs, val) 122 123 #ifdef CONFIG_SMP 124 extern unsigned long profile_pc(struct pt_regs *regs); 125 #define profile_pc profile_pc 126 #endif 127 128 #include <asm-generic/ptrace.h> 129 130 #define kernel_stack_pointer(regs) ((regs)->gpr[1]) 131 static inline int is_syscall_success(struct pt_regs *regs) 132 { 133 return !(regs->ccr & 0x10000000); 134 } 135 136 static inline long regs_return_value(struct pt_regs *regs) 137 { 138 if (is_syscall_success(regs)) 139 return regs->gpr[3]; 140 else 141 return -regs->gpr[3]; 142 } 143 144 static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc) 145 { 146 regs->gpr[3] = rc; 147 } 148 149 #ifdef __powerpc64__ 150 #define user_mode(regs) ((((regs)->msr) >> MSR_PR_LG) & 0x1) 151 #else 152 #define user_mode(regs) (((regs)->msr & MSR_PR) != 0) 153 #endif 154 155 #define force_successful_syscall_return() \ 156 do { \ 157 set_thread_flag(TIF_NOERROR); \ 158 } while(0) 159 160 struct task_struct; 161 extern int ptrace_get_reg(struct task_struct *task, int regno, 162 unsigned long *data); 163 extern int ptrace_put_reg(struct task_struct *task, int regno, 164 unsigned long data); 165 166 #define current_pt_regs() \ 167 ((struct pt_regs *)((unsigned long)task_stack_page(current) + THREAD_SIZE) - 1) 168 /* 169 * We use the least-significant bit of the trap field to indicate 170 * whether we have saved the full set of registers, or only a 171 * partial set. A 1 there means the partial set. 172 * On 4xx we use the next bit to indicate whether the exception 173 * is a critical exception (1 means it is). 174 */ 175 #define FULL_REGS(regs) (((regs)->trap & 1) == 0) 176 #ifndef __powerpc64__ 177 #define IS_CRITICAL_EXC(regs) (((regs)->trap & 2) != 0) 178 #define IS_MCHECK_EXC(regs) (((regs)->trap & 4) != 0) 179 #define IS_DEBUG_EXC(regs) (((regs)->trap & 8) != 0) 180 #endif /* ! __powerpc64__ */ 181 #define TRAP(regs) ((regs)->trap & ~0xF) 182 #ifdef __powerpc64__ 183 #define NV_REG_POISON 0xdeadbeefdeadbeefUL 184 #define CHECK_FULL_REGS(regs) BUG_ON(regs->trap & 1) 185 #else 186 #define NV_REG_POISON 0xdeadbeef 187 #define CHECK_FULL_REGS(regs) \ 188 do { \ 189 if ((regs)->trap & 1) \ 190 printk(KERN_CRIT "%s: partial register set\n", __func__); \ 191 } while (0) 192 #endif /* __powerpc64__ */ 193 194 #define arch_has_single_step() (1) 195 #define arch_has_block_step() (!cpu_has_feature(CPU_FTR_601)) 196 #define ARCH_HAS_USER_SINGLE_STEP_REPORT 197 198 /* 199 * kprobe-based event tracer support 200 */ 201 202 #include <linux/stddef.h> 203 #include <linux/thread_info.h> 204 extern int regs_query_register_offset(const char *name); 205 extern const char *regs_query_register_name(unsigned int offset); 206 #define MAX_REG_OFFSET (offsetof(struct pt_regs, dsisr)) 207 208 /** 209 * regs_get_register() - get register value from its offset 210 * @regs: pt_regs from which register value is gotten 211 * @offset: offset number of the register. 212 * 213 * regs_get_register returns the value of a register whose offset from @regs. 214 * The @offset is the offset of the register in struct pt_regs. 215 * If @offset is bigger than MAX_REG_OFFSET, this returns 0. 216 */ 217 static inline unsigned long regs_get_register(struct pt_regs *regs, 218 unsigned int offset) 219 { 220 if (unlikely(offset > MAX_REG_OFFSET)) 221 return 0; 222 return *(unsigned long *)((unsigned long)regs + offset); 223 } 224 225 /** 226 * regs_within_kernel_stack() - check the address in the stack 227 * @regs: pt_regs which contains kernel stack pointer. 228 * @addr: address which is checked. 229 * 230 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s). 231 * If @addr is within the kernel stack, it returns true. If not, returns false. 232 */ 233 234 static inline bool regs_within_kernel_stack(struct pt_regs *regs, 235 unsigned long addr) 236 { 237 return ((addr & ~(THREAD_SIZE - 1)) == 238 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))); 239 } 240 241 /** 242 * regs_get_kernel_stack_nth() - get Nth entry of the stack 243 * @regs: pt_regs which contains kernel stack pointer. 244 * @n: stack entry number. 245 * 246 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which 247 * is specified by @regs. If the @n th entry is NOT in the kernel stack, 248 * this returns 0. 249 */ 250 static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, 251 unsigned int n) 252 { 253 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs); 254 addr += n; 255 if (regs_within_kernel_stack(regs, (unsigned long)addr)) 256 return *addr; 257 else 258 return 0; 259 } 260 261 #endif /* __ASSEMBLY__ */ 262 263 #ifndef __powerpc64__ 264 #else /* __powerpc64__ */ 265 #define PT_FPSCR32 (PT_FPR0 + 2*32 + 1) /* each FP reg occupies 2 32-bit userspace slots */ 266 #define PT_VR0_32 164 /* each Vector reg occupies 4 slots in 32-bit */ 267 #define PT_VSCR_32 (PT_VR0 + 32*4 + 3) 268 #define PT_VRSAVE_32 (PT_VR0 + 33*4) 269 #define PT_VSR0_32 300 /* each VSR reg occupies 4 slots in 32-bit */ 270 #endif /* __powerpc64__ */ 271 #endif /* _ASM_POWERPC_PTRACE_H */ 272