diff options
Diffstat (limited to 'arch/ppc/kernel/ptrace.c')
| -rw-r--r-- | arch/ppc/kernel/ptrace.c | 474 |
1 files changed, 474 insertions, 0 deletions
diff --git a/arch/ppc/kernel/ptrace.c b/arch/ppc/kernel/ptrace.c new file mode 100644 index 000000000000..426b6f7d9de3 --- /dev/null +++ b/arch/ppc/kernel/ptrace.c @@ -0,0 +1,474 @@ +/* + * arch/ppc/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 <linux/security.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. + */ +#if defined(CONFIG_40x) || defined(CONFIG_BOOKE) +#define MSR_DEBUGCHANGE 0 +#else +#define MSR_DEBUGCHANGE (MSR_SE | MSR_BE) +#endif + +/* + * 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) + && task->thread.regs != NULL) + 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_MQ && task->thread.regs != NULL) { + 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 __user *data, struct task_struct *task) +{ + int i, j; + + if (!access_ok(VERIFY_WRITE, data, 133 * sizeof(unsigned long))) + return -EFAULT; + + /* copy AltiVec registers VR[0] .. VR[31] */ + for (i = 0; i < 32; i++) + for (j = 0; j < 4; j++, data++) + if (__put_user(task->thread.vr[i].u[j], data)) + return -EFAULT; + + /* copy VSCR */ + for (i = 0; i < 4; i++, data++) + if (__put_user(task->thread.vscr.u[i], data)) + return -EFAULT; + + /* copy VRSAVE */ + if (__put_user(task->thread.vrsave, data)) + return -EFAULT; + + return 0; +} + +/* + * Write contents of AltiVec register state into task TASK. + */ +static inline int set_vrregs(struct task_struct *task, unsigned long __user *data) +{ + int i, j; + + if (!access_ok(VERIFY_READ, data, 133 * sizeof(unsigned long))) + return -EFAULT; + + /* copy AltiVec registers VR[0] .. VR[31] */ + for (i = 0; i < 32; i++) + for (j = 0; j < 4; j++, data++) + if (__get_user(task->thread.vr[i].u[j], data)) + return -EFAULT; + + /* copy VSCR */ + for (i = 0; i < 4; i++, data++) + if (__get_user(task->thread.vscr.u[i], data)) + return -EFAULT; + + /* copy VRSAVE */ + if (__get_user(task->thread.vrsave, data)) + return -EFAULT; + + return 0; +} +#endif + +#ifdef CONFIG_SPE + +/* + * For get_evrregs/set_evrregs functions 'data' has the following layout: + * + * struct { + * u32 evr[32]; + * u64 acc; + * u32 spefscr; + * } + */ + +/* + * Get contents of SPE register state in task TASK. + */ +static inline int get_evrregs(unsigned long *data, struct task_struct *task) +{ + int i; + + if (!access_ok(VERIFY_WRITE, data, 35 * sizeof(unsigned long))) + return -EFAULT; + + /* copy SPEFSCR */ + if (__put_user(task->thread.spefscr, &data[34])) + return -EFAULT; + + /* copy SPE registers EVR[0] .. EVR[31] */ + for (i = 0; i < 32; i++, data++) + if (__put_user(task->thread.evr[i], data)) + return -EFAULT; + + /* copy ACC */ + if (__put_user64(task->thread.acc, (unsigned long long *)data)) + return -EFAULT; + + return 0; +} + +/* + * Write contents of SPE register state into task TASK. + */ +static inline int set_evrregs(struct task_struct *task, unsigned long *data) +{ + int i; + + if (!access_ok(VERIFY_READ, data, 35 * sizeof(unsigned long))) + return -EFAULT; + + /* copy SPEFSCR */ + if (__get_user(task->thread.spefscr, &data[34])) + return -EFAULT; + + /* copy SPE registers EVR[0] .. EVR[31] */ + for (i = 0; i < 32; i++, data++) + if (__get_user(task->thread.evr[i], data)) + return -EFAULT; + /* copy ACC */ + if (__get_user64(task->thread.acc, (unsigned long long*)data)) + return -EFAULT; + + return 0; +} +#endif /* CONFIG_SPE */ + +static inline void +set_single_step(struct task_struct *task) +{ + struct pt_regs *regs = task->thread.regs; + + if (regs != NULL) { +#if defined(CONFIG_40x) || defined(CONFIG_BOOKE) + task->thread.dbcr0 = DBCR0_IDM | DBCR0_IC; + regs->msr |= MSR_DE; +#else + regs->msr |= MSR_SE; +#endif + } +} + +static inline void +clear_single_step(struct task_struct *task) +{ + struct pt_regs *regs = task->thread.regs; + + if (regs != NULL) { +#if defined(CONFIG_40x) || defined(CONFIG_BOOKE) + task->thread.dbcr0 = 0; + regs->msr &= ~MSR_DE; +#else + regs->msr &= ~MSR_SE; +#endif + } +} + +/* + * 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; + ret = security_ptrace(current->parent, current); + if (ret) + 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 __user *) data); + break; + } + + /* read the word at location addr in the USER area. */ + /* XXX this will need fixing for 64-bit */ + case PTRACE_PEEKUSR: { + unsigned long index, tmp; + + ret = -EIO; + /* convert to index and check */ + index = (unsigned long) addr >> 2; + if ((addr & 3) || index > PT_FPSCR + || child->thread.regs == NULL) + break; + + CHECK_FULL_REGS(child->thread.regs); + if (index < PT_FPR0) { + tmp = get_reg(child, (int) index); + } else { + preempt_disable(); + if (child->thread.regs->msr & MSR_FP) + giveup_fpu(child); + preempt_enable(); + tmp = ((unsigned long *)child->thread.fpr)[index - PT_FPR0]; + } + ret = put_user(tmp,(unsigned long __user *) 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 >> 2; + if ((addr & 3) || index > PT_FPSCR + || child->thread.regs == NULL) + break; + + CHECK_FULL_REGS(child->thread.regs); + if (index == PT_ORIG_R3) + break; + if (index < PT_FPR0) { + ret = put_reg(child, index, data); + } else { + preempt_disable(); + if (child->thread.regs->msr & MSR_FP) + giveup_fpu(child); + preempt_enable(); + ((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) { + 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. */ + 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->exit_state == EXIT_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; + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + 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; + +#ifdef CONFIG_ALTIVEC + case PTRACE_GETVRREGS: + /* Get the child altivec register state. */ + preempt_disable(); + if (child->thread.regs->msr & MSR_VEC) + giveup_altivec(child); + preempt_enable(); + ret = get_vrregs((unsigned long __user *)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 */ + preempt_disable(); + if (child->thread.regs->msr & MSR_VEC) + giveup_altivec(child); + preempt_enable(); + ret = set_vrregs(child, (unsigned long __user *)data); + break; +#endif +#ifdef CONFIG_SPE + case PTRACE_GETEVRREGS: + /* Get the child spe register state. */ + if (child->thread.regs->msr & MSR_SPE) + giveup_spe(child); + ret = get_evrregs((unsigned long __user *)data, child); + break; + + case PTRACE_SETEVRREGS: + /* Set the child spe register state. */ + /* this is to clear the MSR_SPE bit to force a reload + * of register state from memory */ + if (child->thread.regs->msr & MSR_SPE) + giveup_spe(child); + ret = set_evrregs(child, (unsigned long __user *)data); + break; +#endif + + default: + ret = ptrace_request(child, request, addr, data); + break; + } +out_tsk: + put_task_struct(child); +out: + unlock_kernel(); + return ret; +} + +void do_syscall_trace(void) +{ + if (!test_thread_flag(TIF_SYSCALL_TRACE) + || !(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; + } +} |
