diff options
Diffstat (limited to 'arch/m68k/kernel/ptrace.c')
| -rw-r--r-- | arch/m68k/kernel/ptrace.c | 393 |
1 files changed, 393 insertions, 0 deletions
diff --git a/arch/m68k/kernel/ptrace.c b/arch/m68k/kernel/ptrace.c new file mode 100644 index 00000000000..0beb53333ba --- /dev/null +++ b/arch/m68k/kernel/ptrace.c @@ -0,0 +1,393 @@ +/* + * 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/smp_lock.h> +#include <linux/errno.h> +#include <linux/ptrace.h> +#include <linux/user.h> +#include <linux/config.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 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[] = { + [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 < sizeof(regoff)/sizeof(regoff[0])) + 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 < sizeof(regoff)/sizeof(regoff[0])) + 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); + child->thread.work.delayed_trace = 0; + child->thread.work.syscall_trace = 0; +} + +asmlinkage int sys_ptrace(long request, long pid, long addr, long data) +{ + struct task_struct *child; + int ret; + + lock_kernel(); + ret = -EPERM; + if (request == PTRACE_TRACEME) { + /* are we already being traced? */ + if (current->ptrace & PT_PTRACED) + goto out; + /* set the ptrace bit in the process flags. */ + current->ptrace |= PT_PTRACED; + ret = 0; + goto out; + } + ret = -ESRCH; + read_lock(&tasklist_lock); + child = find_task_by_pid(pid); + if (child) + get_task_struct(child); + read_unlock(&tasklist_lock); + if (!child) + goto out; + + ret = -EPERM; + if (pid == 1) /* you may not mess with init */ + goto out_tsk; + + if (request == PTRACE_ATTACH) { + ret = ptrace_attach(child); + goto out_tsk; + } + + ret = ptrace_check_attach(child, request == PTRACE_KILL); + if (ret < 0) + goto out_tsk; + + 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: { + unsigned long tmp; + int copied; + + copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); + ret = -EIO; + if (copied != sizeof(tmp)) + break; + ret = put_user(tmp,(unsigned long *) 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 + 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 = 0; + if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data)) + break; + ret = -EIO; + 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 ((unsigned long) data > _NSIG) + break; + if (request == PTRACE_SYSCALL) { + child->thread.work.syscall_trace = ~0; + } else { + child->thread.work.syscall_trace = 0; + } + 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); + child->thread.work.delayed_trace = 0; + 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); + child->thread.work.delayed_trace = 0; + wake_up_process(child); + break; + } + + case PTRACE_SINGLESTEP: { /* set the trap flag. */ + long tmp; + + ret = -EIO; + if ((unsigned long) data > _NSIG) + break; + child->thread.work.syscall_trace = 0; + tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16); + put_reg(child, PT_SR, tmp); + child->thread.work.delayed_trace = 1; + + 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; + } + + 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; + } + + 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; + } + + default: + ret = ptrace_request(child, request, addr, data); + break; + } +out_tsk: + put_task_struct(child); +out: + unlock_kernel(); + return ret; +} + +asmlinkage void syscall_trace(void) +{ + if (!current->thread.work.delayed_trace && + !current->thread.work.syscall_trace) + 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; + } +} |