/* * linux/arch/m68knommu/kernel/ptrace.c * * Copyright (C) 1994 by Hamish Macdonald * Taken from linux/kernel/ptrace.c and modified for M680x0. * linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds * * This file is subject to the terms and conditions of the GNU General * Public License. See the file COPYING in the main directory of * this archive for more details. */ #include #include #include #include #include #include #include #include #include #include #include #include #include /* * does not yet catch signals sent when the child dies. * in exit.c or in signal.c. */ /* determines which bits in the SR the user has access to. */ /* 1 = access 0 = no access */ #define SR_MASK 0x001f /* sets the trace bits. */ #define TRACE_BITS 0x8000 /* Find the stack offset for a register, relative to thread.esp0. */ #define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg) #define SW_REG(reg) ((long)&((struct switch_stack *)0)->reg \ - sizeof(struct switch_stack)) /* Mapping from PT_xxx to the stack offset at which the register is saved. Notice that usp has no stack-slot and needs to be treated specially (see get_reg/put_reg below). */ static int regoff[] = { PT_REG(d1), PT_REG(d2), PT_REG(d3), PT_REG(d4), PT_REG(d5), SW_REG(d6), SW_REG(d7), PT_REG(a0), PT_REG(a1), PT_REG(a2), SW_REG(a3), SW_REG(a4), SW_REG(a5), SW_REG(a6), PT_REG(d0), -1, PT_REG(orig_d0), PT_REG(sr), PT_REG(pc), }; /* * Get contents of register REGNO in task TASK. */ static inline long get_reg(struct task_struct *task, int regno) { unsigned long *addr; if (regno == PT_USP) addr = &task->thread.usp; else if (regno < ARRAY_SIZE(regoff)) addr = (unsigned long *)(task->thread.esp0 + regoff[regno]); else return 0; return *addr; } /* * Write contents of register REGNO in task TASK. */ static inline int put_reg(struct task_struct *task, int regno, unsigned long data) { unsigned long *addr; if (regno == PT_USP) addr = &task->thread.usp; else if (regno < ARRAY_SIZE(regoff)) addr = (unsigned long *) (task->thread.esp0 + regoff[regno]); else return -1; *addr = data; return 0; } /* * Called by kernel/ptrace.c when detaching.. * * Make sure the single step bit is not set. */ void ptrace_disable(struct task_struct *child) { unsigned long tmp; /* make sure the single step bit is not set. */ tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16); put_reg(child, PT_SR, tmp); } long arch_ptrace(struct task_struct *child, long request, long addr, long data) { int ret; switch (request) { /* when I and D space are separate, these will need to be fixed. */ case PTRACE_PEEKTEXT: /* read word at location addr. */ case PTRACE_PEEKDATA: ret = generic_ptrace_peekdata(child, addr, data); break; /* read the word at location addr in the USER area. */ case PTRACE_PEEKUSR: { unsigned long tmp; ret = -EIO; if ((addr & 3) || addr < 0 || addr > sizeof(struct user) - 3) break; tmp = 0; /* Default return condition */ addr = addr >> 2; /* temporary hack. */ ret = -EIO; if (addr < 19) { tmp = get_reg(child, addr); if (addr == PT_SR) tmp >>= 16; } else if (addr >= 21 && addr < 49) { tmp = child->thread.fp[addr - 21]; #ifdef CONFIG_M68KFPU_EMU /* Convert internal fpu reg representation * into long double format */ if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) tmp = ((tmp & 0xffff0000) << 15) | ((tmp & 0x0000ffff) << 16); #endif } else if (addr == 49) { tmp = child->mm->start_code; } else if (addr == 50) { tmp = child->mm->start_data; } else if (addr == 51) { tmp = child->mm->end_code; } else break; ret = put_user(tmp,(unsigned long *) data); break; } /* when I and D space are separate, this will have to be fixed. */ case PTRACE_POKETEXT: /* write the word at location addr. */ case PTRACE_POKEDATA: ret = generic_ptrace_pokedata(child, addr, data); break; case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ ret = -EIO; if ((addr & 3) || addr < 0 || addr > sizeof(struct user) - 3) break; addr = addr >> 2; /* temporary hack. */ if (addr == PT_SR) { data &= SR_MASK; data <<= 16; data |= get_reg(child, PT_SR) & ~(SR_MASK << 16); } if (addr < 19) { if (put_reg(child, addr, data)) break; ret = 0; break; } if (addr >= 21 && addr < 48) { #ifdef CONFIG_M68KFPU_EMU /* Convert long double format * into internal fpu reg representation */ if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) { data = (unsigned long)data << 15; data = (data & 0xffff0000) | ((data & 0x0000ffff) >> 1); } #endif child->thread.fp[addr - 21] = data; ret = 0; } break; case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ case PTRACE_CONT: { /* restart after signal. */ long tmp; ret = -EIO; if (!valid_signal(data)) break; if (request == PTRACE_SYSCALL) set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); else clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); child->exit_code = data; /* make sure the single step bit is not set. */ tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16); put_reg(child, PT_SR, tmp); wake_up_process(child); ret = 0; break; } /* * make the child exit. Best I can do is send it a sigkill. * perhaps it should be put in the status that it wants to * exit. */ case PTRACE_KILL: { long tmp; ret = 0; if (child->exit_state == EXIT_ZOMBIE) /* already dead */ break; child->exit_code = SIGKILL; /* make sure the single step bit is not set. */ tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16); put_reg(child, PT_SR, tmp); wake_up_process(child); break; } case PTRACE_SINGLESTEP: { /* set the trap flag. */ long tmp; ret = -EIO; if (!valid_signal(data)) break; clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16); put_reg(child, PT_SR, tmp); child->exit_code = data; /* give it a chance to run. */ wake_up_process(child); ret = 0; break; } case PTRACE_DETACH: /* detach a process that was attached. */ ret = ptrace_detach(child, data); break; case PTRACE_GETREGS: { /* Get all gp regs from the child. */ int i; unsigned long tmp; for (i = 0; i < 19; i++) { tmp = get_reg(child, i); if (i == PT_SR) tmp >>= 16; if (put_user(tmp, (unsigned long *) data)) { ret = -EFAULT; break; } data += sizeof(long); } ret = 0; break; } case PTRACE_SETREGS: { /* Set all gp regs in the child. */ int i; unsigned long tmp; for (i = 0; i < 19; i++) { if (get_user(tmp, (unsigned long *) data)) { ret = -EFAULT; break; } if (i == PT_SR) { tmp &= SR_MASK; tmp <<= 16; tmp |= get_reg(child, PT_SR) & ~(SR_MASK << 16); } put_reg(child, i, tmp); data += sizeof(long); } ret = 0; break; } #ifdef PTRACE_GETFPREGS case PTRACE_GETFPREGS: { /* Get the child FPU state. */ ret = 0; if (copy_to_user((void *)data, &child->thread.fp, sizeof(struct user_m68kfp_struct))) ret = -EFAULT; break; } #endif #ifdef PTRACE_SETFPREGS case PTRACE_SETFPREGS: { /* Set the child FPU state. */ ret = 0; if (copy_from_user(&child->thread.fp, (void *)data, sizeof(struct user_m68kfp_struct))) ret = -EFAULT; break; } #endif default: ret = -EIO; break; } return ret; } asmlinkage void syscall_trace(void) { if (!test_thread_flag(TIF_SYSCALL_TRACE)) return; if (!(current->ptrace & PT_PTRACED)) return; ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80 : 0)); /* * this isn't the same as continuing with a signal, but it will do * for normal use. strace only continues with a signal if the * stopping signal is not SIGTRAP. -brl */ if (current->exit_code) { send_sig(current->exit_code, current, 1); current->exit_code = 0; } }