| /* |
| * linux/arch/ppc64/kernel/ptrace.c |
| * |
| * PowerPC version |
| * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) |
| * |
| * Derived from "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 |
| * |
| * Modified by Cort Dougan (cort@hq.fsmlabs.com) |
| * and Paul Mackerras (paulus@linuxcare.com.au). |
| * |
| * This file is subject to the terms and conditions of the GNU General |
| * Public License. See the file README.legal 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 <asm/uaccess.h> |
| #include <asm/page.h> |
| #include <asm/pgtable.h> |
| #include <asm/system.h> |
| |
| /* |
| * Set of msr bits that gdb can change on behalf of a process. |
| */ |
| #define MSR_DEBUGCHANGE (MSR_FE0 | MSR_SE | MSR_BE | MSR_FE1) |
| |
| /* |
| * does not yet catch signals sent when the child dies. |
| * in exit.c or in signal.c. |
| */ |
| |
| /* |
| * Get contents of register REGNO in task TASK. |
| */ |
| static inline unsigned long get_reg(struct task_struct *task, int regno) |
| { |
| if (regno < sizeof(struct pt_regs) / sizeof(unsigned long)) |
| return ((unsigned long *)task->thread.regs)[regno]; |
| return (0); |
| } |
| |
| /* |
| * Write contents of register REGNO in task TASK. |
| */ |
| static inline int put_reg(struct task_struct *task, int regno, |
| unsigned long data) |
| { |
| if (regno < PT_SOFTE) { |
| if (regno == PT_MSR) |
| data = (data & MSR_DEBUGCHANGE) |
| | (task->thread.regs->msr & ~MSR_DEBUGCHANGE); |
| ((unsigned long *)task->thread.regs)[regno] = data; |
| return 0; |
| } |
| return -EIO; |
| } |
| |
| #ifdef CONFIG_ALTIVEC |
| /* |
| * Get contents of AltiVec register state in task TASK |
| */ |
| static inline int get_vrregs(unsigned long data, struct task_struct *task) |
| { |
| return (copy_to_user((void *)data,&task->thread.vr[0], |
| offsetof(struct thread_struct,vrsave[2])- |
| offsetof(struct thread_struct,vr[0])) ? -EFAULT : 0 ); |
| } |
| |
| /* |
| * Write contents of AltiVec register state into task TASK. |
| */ |
| static inline int set_vrregs(struct task_struct *task, unsigned long data) |
| { |
| return (copy_from_user(&task->thread.vr[0],(void *)data, |
| offsetof(struct thread_struct,vrsave[2])- |
| offsetof(struct thread_struct,vr[0])) ? -EFAULT : 0 ); |
| } |
| #endif |
| |
| static inline void |
| set_single_step(struct task_struct *task) |
| { |
| struct pt_regs *regs = task->thread.regs; |
| if (regs != NULL) |
| regs->msr |= MSR_SE; |
| } |
| |
| static inline void |
| clear_single_step(struct task_struct *task) |
| { |
| struct pt_regs *regs = task->thread.regs; |
| if (regs != NULL) |
| regs->msr &= ~MSR_SE; |
| } |
| |
| /* |
| * Called by kernel/ptrace.c when detaching.. |
| * |
| * Make sure single step bits etc are not set. |
| */ |
| void ptrace_disable(struct task_struct *child) |
| { |
| /* make sure the single step bit is not set. */ |
| clear_single_step(child); |
| } |
| |
| int sys_ptrace(long request, long pid, long addr, long data) |
| { |
| struct task_struct *child; |
| int ret = -EPERM; |
| |
| lock_kernel(); |
| 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 index; |
| unsigned long tmp; |
| |
| ret = -EIO; |
| /* convert to index and check */ |
| index = (unsigned long) addr >> 3; |
| if ((addr & 7) || (index > PT_FPSCR)) |
| break; |
| |
| if (index < PT_FPR0) { |
| tmp = get_reg(child, (int)index); |
| } else { |
| if (child->thread.regs->msr & MSR_FP) |
| giveup_fpu(child); |
| tmp = ((unsigned long *)child->thread.fpr)[index - PT_FPR0]; |
| } |
| ret = put_user(tmp,(unsigned long *) data); |
| break; |
| } |
| |
| /* If 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; |
| |
| /* write the word at location addr in the USER area */ |
| case PTRACE_POKEUSR: { |
| unsigned long index; |
| |
| ret = -EIO; |
| /* convert to index and check */ |
| index = (unsigned long) addr >> 3; |
| if ((addr & 7) || (index > PT_FPSCR)) |
| break; |
| |
| if (index == PT_ORIG_R3) |
| break; |
| if (index < PT_FPR0) { |
| ret = put_reg(child, index, data); |
| } else { |
| if (child->thread.regs->msr & MSR_FP) |
| giveup_fpu(child); |
| ((unsigned long *)child->thread.fpr)[index - PT_FPR0] = data; |
| ret = 0; |
| } |
| break; |
| } |
| |
| case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ |
| case PTRACE_CONT: { /* restart after signal. */ |
| ret = -EIO; |
| if ((unsigned long) data > _NSIG) |
| break; |
| if (request == PTRACE_SYSCALL) |
| child->ptrace |= PT_TRACESYS; |
| else |
| child->ptrace &= ~PT_TRACESYS; |
| child->exit_code = data; |
| /* make sure the single step bit is not set. */ |
| clear_single_step(child); |
| 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: { |
| ret = 0; |
| if (child->state == TASK_ZOMBIE) /* already dead */ |
| break; |
| child->exit_code = SIGKILL; |
| /* make sure the single step bit is not set. */ |
| clear_single_step(child); |
| wake_up_process(child); |
| break; |
| } |
| |
| case PTRACE_SINGLESTEP: { /* set the trap flag. */ |
| ret = -EIO; |
| if ((unsigned long) data > _NSIG) |
| break; |
| child->ptrace &= ~PT_TRACESYS; |
| set_single_step(child); |
| child->exit_code = data; |
| /* give it a chance to run. */ |
| wake_up_process(child); |
| ret = 0; |
| break; |
| } |
| |
| case PTRACE_DETACH: |
| ret = ptrace_detach(child, data); |
| break; |
| |
| case PPC_PTRACE_GETREGS: { /* Get GPRs 0 - 31. */ |
| int i; |
| unsigned long *reg = &((unsigned long *)child->thread.regs)[0]; |
| unsigned long *tmp = (unsigned long *)addr; |
| |
| for (i = 0; i < 32; i++) { |
| ret = put_user(*reg, tmp); |
| if (ret) |
| break; |
| reg++; |
| tmp++; |
| } |
| break; |
| } |
| |
| case PPC_PTRACE_SETREGS: { /* Set GPRs 0 - 31. */ |
| int i; |
| unsigned long *reg = &((unsigned long *)child->thread.regs)[0]; |
| unsigned long *tmp = (unsigned long *)addr; |
| |
| for (i = 0; i < 32; i++) { |
| ret = get_user(*reg, tmp); |
| if (ret) |
| break; |
| reg++; |
| tmp++; |
| } |
| break; |
| } |
| |
| case PPC_PTRACE_GETFPREGS: { /* Get FPRs 0 - 31. */ |
| int i; |
| unsigned long *reg = &((unsigned long *)child->thread.fpr)[0]; |
| unsigned long *tmp = (unsigned long *)addr; |
| |
| if (child->thread.regs->msr & MSR_FP) |
| giveup_fpu(child); |
| |
| for (i = 0; i < 32; i++) { |
| ret = put_user(*reg, tmp); |
| if (ret) |
| break; |
| reg++; |
| tmp++; |
| } |
| break; |
| } |
| |
| case PPC_PTRACE_SETFPREGS: { /* Get FPRs 0 - 31. */ |
| int i; |
| unsigned long *reg = &((unsigned long *)child->thread.fpr)[0]; |
| unsigned long *tmp = (unsigned long *)addr; |
| |
| if (child->thread.regs->msr & MSR_FP) |
| giveup_fpu(child); |
| |
| for (i = 0; i < 32; i++) { |
| ret = get_user(*reg, tmp); |
| if (ret) |
| break; |
| reg++; |
| tmp++; |
| } |
| break; |
| } |
| #ifdef CONFIG_ALTIVEC |
| case PTRACE_GETVRREGS: |
| /* Get the child altivec register state. */ |
| if (child->thread.regs->msr & MSR_VEC) |
| giveup_altivec(child); |
| ret = get_vrregs(data, child); |
| break; |
| |
| case PTRACE_SETVRREGS: |
| /* Set the child altivec register state. */ |
| /* this is to clear the MSR_VEC bit to force a reload |
| * of register state from memory */ |
| if (child->thread.regs->msr & MSR_VEC) |
| giveup_altivec(child); |
| ret = set_vrregs(child,data); |
| break; |
| #endif |
| |
| default: |
| ret = -EIO; |
| break; |
| } |
| out_tsk: |
| free_task_struct(child); |
| out: |
| unlock_kernel(); |
| return ret; |
| } |
| |
| void syscall_trace(void) |
| { |
| if ((current->ptrace & (PT_PTRACED|PT_TRACESYS)) |
| != (PT_PTRACED|PT_TRACESYS)) |
| return; |
| current->exit_code = SIGTRAP; |
| current->state = TASK_STOPPED; |
| notify_parent(current, SIGCHLD); |
| schedule(); |
| /* |
| * 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; |
| } |
| } |