| /* | 
 |  *  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 <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[] = { | 
 | 	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; | 
 | 	} | 
 | } |