Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/m68knommu/kernel/ptrace.c |
| 3 | * |
| 4 | * Copyright (C) 1994 by Hamish Macdonald |
| 5 | * Taken from linux/kernel/ptrace.c and modified for M680x0. |
| 6 | * linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds |
| 7 | * |
| 8 | * This file is subject to the terms and conditions of the GNU General |
| 9 | * Public License. See the file COPYING in the main directory of |
| 10 | * this archive for more details. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/sched.h> |
| 15 | #include <linux/mm.h> |
| 16 | #include <linux/smp.h> |
| 17 | #include <linux/smp_lock.h> |
| 18 | #include <linux/errno.h> |
| 19 | #include <linux/ptrace.h> |
| 20 | #include <linux/user.h> |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 21 | #include <linux/signal.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | |
| 23 | #include <asm/uaccess.h> |
| 24 | #include <asm/page.h> |
| 25 | #include <asm/pgtable.h> |
| 26 | #include <asm/system.h> |
| 27 | #include <asm/processor.h> |
| 28 | |
| 29 | /* |
| 30 | * does not yet catch signals sent when the child dies. |
| 31 | * in exit.c or in signal.c. |
| 32 | */ |
| 33 | |
| 34 | /* determines which bits in the SR the user has access to. */ |
| 35 | /* 1 = access 0 = no access */ |
| 36 | #define SR_MASK 0x001f |
| 37 | |
| 38 | /* sets the trace bits. */ |
| 39 | #define TRACE_BITS 0x8000 |
| 40 | |
| 41 | /* Find the stack offset for a register, relative to thread.esp0. */ |
| 42 | #define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg) |
| 43 | #define SW_REG(reg) ((long)&((struct switch_stack *)0)->reg \ |
| 44 | - sizeof(struct switch_stack)) |
| 45 | /* Mapping from PT_xxx to the stack offset at which the register is |
| 46 | saved. Notice that usp has no stack-slot and needs to be treated |
| 47 | specially (see get_reg/put_reg below). */ |
| 48 | static int regoff[] = { |
| 49 | PT_REG(d1), PT_REG(d2), PT_REG(d3), PT_REG(d4), |
| 50 | PT_REG(d5), SW_REG(d6), SW_REG(d7), PT_REG(a0), |
| 51 | PT_REG(a1), PT_REG(a2), SW_REG(a3), SW_REG(a4), |
| 52 | SW_REG(a5), SW_REG(a6), PT_REG(d0), -1, |
| 53 | PT_REG(orig_d0), PT_REG(sr), PT_REG(pc), |
| 54 | }; |
| 55 | |
| 56 | /* |
| 57 | * Get contents of register REGNO in task TASK. |
| 58 | */ |
| 59 | static inline long get_reg(struct task_struct *task, int regno) |
| 60 | { |
| 61 | unsigned long *addr; |
| 62 | |
| 63 | if (regno == PT_USP) |
| 64 | addr = &task->thread.usp; |
| 65 | else if (regno < sizeof(regoff)/sizeof(regoff[0])) |
| 66 | addr = (unsigned long *)(task->thread.esp0 + regoff[regno]); |
| 67 | else |
| 68 | return 0; |
| 69 | return *addr; |
| 70 | } |
| 71 | |
| 72 | /* |
| 73 | * Write contents of register REGNO in task TASK. |
| 74 | */ |
| 75 | static inline int put_reg(struct task_struct *task, int regno, |
| 76 | unsigned long data) |
| 77 | { |
| 78 | unsigned long *addr; |
| 79 | |
| 80 | if (regno == PT_USP) |
| 81 | addr = &task->thread.usp; |
| 82 | else if (regno < sizeof(regoff)/sizeof(regoff[0])) |
| 83 | addr = (unsigned long *) (task->thread.esp0 + regoff[regno]); |
| 84 | else |
| 85 | return -1; |
| 86 | *addr = data; |
| 87 | return 0; |
| 88 | } |
| 89 | |
| 90 | /* |
| 91 | * Called by kernel/ptrace.c when detaching.. |
| 92 | * |
| 93 | * Make sure the single step bit is not set. |
| 94 | */ |
| 95 | void ptrace_disable(struct task_struct *child) |
| 96 | { |
| 97 | unsigned long tmp; |
| 98 | /* make sure the single step bit is not set. */ |
| 99 | tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16); |
| 100 | put_reg(child, PT_SR, tmp); |
| 101 | } |
| 102 | |
Greg Ungerer | afc7cd8 | 2006-01-10 16:42:18 +1000 | [diff] [blame] | 103 | long arch_ptrace(struct task_struct *child, long request, long addr, long data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | int ret; |
| 106 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | switch (request) { |
| 108 | /* when I and D space are separate, these will need to be fixed. */ |
| 109 | case PTRACE_PEEKTEXT: /* read word at location addr. */ |
| 110 | case PTRACE_PEEKDATA: { |
| 111 | unsigned long tmp; |
| 112 | int copied; |
| 113 | |
| 114 | copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); |
| 115 | ret = -EIO; |
| 116 | if (copied != sizeof(tmp)) |
| 117 | break; |
| 118 | ret = put_user(tmp,(unsigned long *) data); |
| 119 | break; |
| 120 | } |
| 121 | |
| 122 | /* read the word at location addr in the USER area. */ |
| 123 | case PTRACE_PEEKUSR: { |
| 124 | unsigned long tmp; |
| 125 | |
| 126 | ret = -EIO; |
| 127 | if ((addr & 3) || addr < 0 || |
| 128 | addr > sizeof(struct user) - 3) |
| 129 | break; |
| 130 | |
| 131 | tmp = 0; /* Default return condition */ |
| 132 | addr = addr >> 2; /* temporary hack. */ |
| 133 | ret = -EIO; |
| 134 | if (addr < 19) { |
| 135 | tmp = get_reg(child, addr); |
| 136 | if (addr == PT_SR) |
| 137 | tmp >>= 16; |
| 138 | } else if (addr >= 21 && addr < 49) { |
| 139 | tmp = child->thread.fp[addr - 21]; |
| 140 | #ifdef CONFIG_M68KFPU_EMU |
| 141 | /* Convert internal fpu reg representation |
| 142 | * into long double format |
| 143 | */ |
| 144 | if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) |
| 145 | tmp = ((tmp & 0xffff0000) << 15) | |
| 146 | ((tmp & 0x0000ffff) << 16); |
| 147 | #endif |
| 148 | } else if (addr == 49) { |
| 149 | tmp = child->mm->start_code; |
| 150 | } else if (addr == 50) { |
| 151 | tmp = child->mm->start_data; |
| 152 | } else if (addr == 51) { |
| 153 | tmp = child->mm->end_code; |
| 154 | } else |
| 155 | break; |
| 156 | ret = put_user(tmp,(unsigned long *) data); |
| 157 | break; |
| 158 | } |
| 159 | |
| 160 | /* when I and D space are separate, this will have to be fixed. */ |
| 161 | case PTRACE_POKETEXT: /* write the word at location addr. */ |
| 162 | case PTRACE_POKEDATA: |
| 163 | ret = 0; |
| 164 | if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data)) |
| 165 | break; |
| 166 | ret = -EIO; |
| 167 | break; |
| 168 | |
| 169 | case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ |
| 170 | ret = -EIO; |
| 171 | if ((addr & 3) || addr < 0 || |
| 172 | addr > sizeof(struct user) - 3) |
| 173 | break; |
| 174 | |
| 175 | addr = addr >> 2; /* temporary hack. */ |
| 176 | |
| 177 | if (addr == PT_SR) { |
| 178 | data &= SR_MASK; |
| 179 | data <<= 16; |
| 180 | data |= get_reg(child, PT_SR) & ~(SR_MASK << 16); |
| 181 | } |
| 182 | if (addr < 19) { |
| 183 | if (put_reg(child, addr, data)) |
| 184 | break; |
| 185 | ret = 0; |
| 186 | break; |
| 187 | } |
| 188 | if (addr >= 21 && addr < 48) |
| 189 | { |
| 190 | #ifdef CONFIG_M68KFPU_EMU |
| 191 | /* Convert long double format |
| 192 | * into internal fpu reg representation |
| 193 | */ |
| 194 | if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) { |
| 195 | data = (unsigned long)data << 15; |
| 196 | data = (data & 0xffff0000) | |
| 197 | ((data & 0x0000ffff) >> 1); |
| 198 | } |
| 199 | #endif |
| 200 | child->thread.fp[addr - 21] = data; |
| 201 | ret = 0; |
| 202 | } |
| 203 | break; |
| 204 | |
| 205 | case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ |
| 206 | case PTRACE_CONT: { /* restart after signal. */ |
| 207 | long tmp; |
| 208 | |
| 209 | ret = -EIO; |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 210 | if (!valid_signal(data)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 211 | break; |
| 212 | if (request == PTRACE_SYSCALL) |
| 213 | set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 214 | else |
| 215 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 216 | child->exit_code = data; |
| 217 | /* make sure the single step bit is not set. */ |
| 218 | tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16); |
| 219 | put_reg(child, PT_SR, tmp); |
| 220 | wake_up_process(child); |
| 221 | ret = 0; |
| 222 | break; |
| 223 | } |
| 224 | |
| 225 | /* |
| 226 | * make the child exit. Best I can do is send it a sigkill. |
| 227 | * perhaps it should be put in the status that it wants to |
| 228 | * exit. |
| 229 | */ |
| 230 | case PTRACE_KILL: { |
| 231 | long tmp; |
| 232 | |
| 233 | ret = 0; |
| 234 | if (child->exit_state == EXIT_ZOMBIE) /* already dead */ |
| 235 | break; |
| 236 | child->exit_code = SIGKILL; |
| 237 | /* make sure the single step bit is not set. */ |
| 238 | tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16); |
| 239 | put_reg(child, PT_SR, tmp); |
| 240 | wake_up_process(child); |
| 241 | break; |
| 242 | } |
| 243 | |
| 244 | case PTRACE_SINGLESTEP: { /* set the trap flag. */ |
| 245 | long tmp; |
| 246 | |
| 247 | ret = -EIO; |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 248 | if (!valid_signal(data)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | break; |
| 250 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 251 | tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16); |
| 252 | put_reg(child, PT_SR, tmp); |
| 253 | |
| 254 | child->exit_code = data; |
| 255 | /* give it a chance to run. */ |
| 256 | wake_up_process(child); |
| 257 | ret = 0; |
| 258 | break; |
| 259 | } |
| 260 | |
| 261 | case PTRACE_DETACH: /* detach a process that was attached. */ |
| 262 | ret = ptrace_detach(child, data); |
| 263 | break; |
| 264 | |
| 265 | case PTRACE_GETREGS: { /* Get all gp regs from the child. */ |
| 266 | int i; |
| 267 | unsigned long tmp; |
| 268 | for (i = 0; i < 19; i++) { |
| 269 | tmp = get_reg(child, i); |
| 270 | if (i == PT_SR) |
| 271 | tmp >>= 16; |
| 272 | if (put_user(tmp, (unsigned long *) data)) { |
| 273 | ret = -EFAULT; |
| 274 | break; |
| 275 | } |
| 276 | data += sizeof(long); |
| 277 | } |
| 278 | ret = 0; |
| 279 | break; |
| 280 | } |
| 281 | |
| 282 | case PTRACE_SETREGS: { /* Set all gp regs in the child. */ |
| 283 | int i; |
| 284 | unsigned long tmp; |
| 285 | for (i = 0; i < 19; i++) { |
| 286 | if (get_user(tmp, (unsigned long *) data)) { |
| 287 | ret = -EFAULT; |
| 288 | break; |
| 289 | } |
| 290 | if (i == PT_SR) { |
| 291 | tmp &= SR_MASK; |
| 292 | tmp <<= 16; |
| 293 | tmp |= get_reg(child, PT_SR) & ~(SR_MASK << 16); |
| 294 | } |
| 295 | put_reg(child, i, tmp); |
| 296 | data += sizeof(long); |
| 297 | } |
| 298 | ret = 0; |
| 299 | break; |
| 300 | } |
| 301 | |
| 302 | #ifdef PTRACE_GETFPREGS |
| 303 | case PTRACE_GETFPREGS: { /* Get the child FPU state. */ |
| 304 | ret = 0; |
| 305 | if (copy_to_user((void *)data, &child->thread.fp, |
| 306 | sizeof(struct user_m68kfp_struct))) |
| 307 | ret = -EFAULT; |
| 308 | break; |
| 309 | } |
| 310 | #endif |
| 311 | |
| 312 | #ifdef PTRACE_SETFPREGS |
| 313 | case PTRACE_SETFPREGS: { /* Set the child FPU state. */ |
| 314 | ret = 0; |
| 315 | if (copy_from_user(&child->thread.fp, (void *)data, |
| 316 | sizeof(struct user_m68kfp_struct))) |
| 317 | ret = -EFAULT; |
| 318 | break; |
| 319 | } |
| 320 | #endif |
| 321 | |
| 322 | default: |
| 323 | ret = -EIO; |
| 324 | break; |
| 325 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 326 | return ret; |
| 327 | } |
| 328 | |
| 329 | asmlinkage void syscall_trace(void) |
| 330 | { |
| 331 | if (!test_thread_flag(TIF_SYSCALL_TRACE)) |
| 332 | return; |
| 333 | if (!(current->ptrace & PT_PTRACED)) |
| 334 | return; |
| 335 | ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) |
| 336 | ? 0x80 : 0)); |
| 337 | /* |
| 338 | * this isn't the same as continuing with a signal, but it will do |
| 339 | * for normal use. strace only continues with a signal if the |
| 340 | * stopping signal is not SIGTRAP. -brl |
| 341 | */ |
| 342 | if (current->exit_code) { |
| 343 | send_sig(current->exit_code, current, 1); |
| 344 | current->exit_code = 0; |
| 345 | } |
| 346 | } |