|  | /* | 
|  | *  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 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 < 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; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * 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 << 16); | 
|  | 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); | 
|  | } | 
|  |  | 
|  | long arch_ptrace(struct task_struct *child, long request, long addr, long data) | 
|  | { | 
|  | unsigned long tmp; | 
|  | int i, ret = 0; | 
|  |  | 
|  | 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: | 
|  | if (addr & 3) | 
|  | goto out_eio; | 
|  | addr >>= 2;	/* temporary hack. */ | 
|  |  | 
|  | if (addr >= 0 && 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]; | 
|  | /* Convert internal fpu reg representation | 
|  | * into long double format | 
|  | */ | 
|  | if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) | 
|  | tmp = ((tmp & 0xffff0000) << 15) | | 
|  | ((tmp & 0x0000ffff) << 16); | 
|  | } 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 */ | 
|  | if (addr & 3) | 
|  | goto out_eio; | 
|  | addr >>= 2;	/* temporary hack. */ | 
|  |  | 
|  | if (addr == PT_SR) { | 
|  | data &= SR_MASK; | 
|  | data <<= 16; | 
|  | data |= get_reg(child, PT_SR) & ~(SR_MASK << 16); | 
|  | } else if (addr >= 0 && addr < 19) { | 
|  | if (put_reg(child, addr, data)) | 
|  | goto out_eio; | 
|  | } else if (addr >= 21 && addr < 48) { | 
|  | /* 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); | 
|  | } | 
|  | child->thread.fp[addr - 21] = data; | 
|  | } else | 
|  | goto out_eio; | 
|  | break; | 
|  |  | 
|  | case PTRACE_SYSCALL:	/* continue and stop at next (return from) syscall */ | 
|  | case PTRACE_CONT:	/* restart after signal. */ | 
|  | if (!valid_signal(data)) | 
|  | goto out_eio; | 
|  |  | 
|  | 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; | 
|  | singlestep_disable(child); | 
|  | wake_up_process(child); | 
|  | 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: | 
|  | if (child->exit_state == EXIT_ZOMBIE) /* already dead */ | 
|  | break; | 
|  | child->exit_code = SIGKILL; | 
|  | singlestep_disable(child); | 
|  | wake_up_process(child); | 
|  | break; | 
|  |  | 
|  | case PTRACE_SINGLESTEP:	/* set the trap flag. */ | 
|  | if (!valid_signal(data)) | 
|  | goto out_eio; | 
|  |  | 
|  | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); | 
|  | tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16); | 
|  | put_reg(child, PT_SR, tmp); | 
|  | set_tsk_thread_flag(child, TIF_DELAYED_TRACE); | 
|  |  | 
|  | child->exit_code = data; | 
|  | /* give it a chance to run. */ | 
|  | wake_up_process(child); | 
|  | break; | 
|  |  | 
|  | case PTRACE_GETREGS:	/* Get all gp regs from the child. */ | 
|  | for (i = 0; i < 19; i++) { | 
|  | tmp = get_reg(child, i); | 
|  | if (i == PT_SR) | 
|  | tmp >>= 16; | 
|  | ret = put_user(tmp, (unsigned long *)data); | 
|  | if (ret) | 
|  | break; | 
|  | data += sizeof(long); | 
|  | } | 
|  | break; | 
|  |  | 
|  | case PTRACE_SETREGS:	/* Set all gp regs in the child. */ | 
|  | for (i = 0; i < 19; i++) { | 
|  | ret = get_user(tmp, (unsigned long *)data); | 
|  | if (ret) | 
|  | 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); | 
|  | } | 
|  | break; | 
|  |  | 
|  | case PTRACE_GETFPREGS:	/* Get the child FPU state. */ | 
|  | 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. */ | 
|  | 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; | 
|  | } | 
|  |  | 
|  | 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; | 
|  | } | 
|  | } |