diff options
Diffstat (limited to 'arch/m68k/kernel/ptrace_mm.c')
-rw-r--r-- | arch/m68k/kernel/ptrace_mm.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/arch/m68k/kernel/ptrace_mm.c b/arch/m68k/kernel/ptrace_mm.c new file mode 100644 index 0000000..0b25268 --- /dev/null +++ b/arch/m68k/kernel/ptrace_mm.c @@ -0,0 +1,277 @@ +/* + * linux/arch/m68k/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 <linux/kernel.h> +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/errno.h> +#include <linux/ptrace.h> +#include <linux/user.h> +#include <linux/signal.h> + +#include <asm/uaccess.h> +#include <asm/page.h> +#include <asm/pgtable.h> +#include <asm/system.h> +#include <asm/processor.h> + +/* + * 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 0xC000 +#define T1_BIT 0x8000 +#define T0_BIT 0x4000 + +/* 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 const int regoff[] = { + [0] = PT_REG(d1), + [1] = PT_REG(d2), + [2] = PT_REG(d3), + [3] = PT_REG(d4), + [4] = PT_REG(d5), + [5] = SW_REG(d6), + [6] = SW_REG(d7), + [7] = PT_REG(a0), + [8] = PT_REG(a1), + [9] = PT_REG(a2), + [10] = SW_REG(a3), + [11] = SW_REG(a4), + [12] = SW_REG(a5), + [13] = SW_REG(a6), + [14] = PT_REG(d0), + [15] = -1, + [16] = PT_REG(orig_d0), + [17] = PT_REG(sr), + [18] = 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; + /* Need to take stkadj into account. */ + if (regno == PT_SR || regno == PT_PC) { + long stkadj = *(long *)(task->thread.esp0 + PT_REG(stkadj)); + addr = (unsigned long *) ((unsigned long)addr + stkadj); + /* The sr is actually a 16 bit register. */ + if (regno == PT_SR) + return *(unsigned short *)addr; + } + 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; + /* Need to take stkadj into account. */ + if (regno == PT_SR || regno == PT_PC) { + long stkadj = *(long *)(task->thread.esp0 + PT_REG(stkadj)); + addr = (unsigned long *) ((unsigned long)addr + stkadj); + /* The sr is actually a 16 bit register. */ + if (regno == PT_SR) { + *(unsigned short *)addr = data; + return 0; + } + } + *addr = data; + return 0; +} + +/* + * Make sure the single step bit is not set. + */ +static inline void singlestep_disable(struct task_struct *child) +{ + unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS; + put_reg(child, PT_SR, tmp); + clear_tsk_thread_flag(child, TIF_DELAYED_TRACE); +} + +/* + * Called by kernel/ptrace.c when detaching.. + */ +void ptrace_disable(struct task_struct *child) +{ + singlestep_disable(child); +} + +void user_enable_single_step(struct task_struct *child) +{ + unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS; + put_reg(child, PT_SR, tmp | T1_BIT); + set_tsk_thread_flag(child, TIF_DELAYED_TRACE); +} + +void user_enable_block_step(struct task_struct *child) +{ + unsigned long tmp = get_reg(child, PT_SR) & ~TRACE_BITS; + put_reg(child, PT_SR, tmp | T0_BIT); +} + +void user_disable_single_step(struct task_struct *child) +{ + singlestep_disable(child); +} + +long arch_ptrace(struct task_struct *child, long request, + unsigned long addr, unsigned long data) +{ + unsigned long tmp; + int i, ret = 0; + int regno = addr >> 2; /* temporary hack. */ + unsigned long __user *datap = (unsigned long __user *) data; + + switch (request) { + /* read the word at location addr in the USER area. */ + case PTRACE_PEEKUSR: + if (addr & 3) + goto out_eio; + + if (regno >= 0 && regno < 19) { + tmp = get_reg(child, regno); + } else if (regno >= 21 && regno < 49) { + tmp = child->thread.fp[regno - 21]; + /* Convert internal fpu reg representation + * into long double format + */ + if (FPU_IS_EMU && (regno < 45) && !(regno % 3)) + tmp = ((tmp & 0xffff0000) << 15) | + ((tmp & 0x0000ffff) << 16); + } else + goto out_eio; + ret = put_user(tmp, datap); + break; + + case PTRACE_POKEUSR: + /* write the word at location addr in the USER area */ + if (addr & 3) + goto out_eio; + + if (regno == PT_SR) { + data &= SR_MASK; + data |= get_reg(child, PT_SR) & ~SR_MASK; + } + if (regno >= 0 && regno < 19) { + if (put_reg(child, regno, data)) + goto out_eio; + } else if (regno >= 21 && regno < 48) { + /* Convert long double format + * into internal fpu reg representation + */ + if (FPU_IS_EMU && (regno < 45) && !(regno % 3)) { + data <<= 15; + data = (data & 0xffff0000) | + ((data & 0x0000ffff) >> 1); + } + child->thread.fp[regno - 21] = data; + } else + goto out_eio; + break; + + case PTRACE_GETREGS: /* Get all gp regs from the child. */ + for (i = 0; i < 19; i++) { + tmp = get_reg(child, i); + ret = put_user(tmp, datap); + if (ret) + break; + datap++; + } + break; + + case PTRACE_SETREGS: /* Set all gp regs in the child. */ + for (i = 0; i < 19; i++) { + ret = get_user(tmp, datap); + if (ret) + break; + if (i == PT_SR) { + tmp &= SR_MASK; + tmp |= get_reg(child, PT_SR) & ~SR_MASK; + } + put_reg(child, i, tmp); + datap++; + } + break; + + case PTRACE_GETFPREGS: /* Get the child FPU state. */ + if (copy_to_user(datap, &child->thread.fp, + sizeof(struct user_m68kfp_struct))) + ret = -EFAULT; + break; + + case PTRACE_SETFPREGS: /* Set the child FPU state. */ + if (copy_from_user(&child->thread.fp, datap, + sizeof(struct user_m68kfp_struct))) + ret = -EFAULT; + break; + + case PTRACE_GET_THREAD_AREA: + ret = put_user(task_thread_info(child)->tp_value, datap); + break; + + default: + ret = ptrace_request(child, request, addr, data); + break; + } + + return ret; +out_eio: + return -EIO; +} + +asmlinkage void syscall_trace(void) +{ + 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; + } +} |