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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/ppc/kernel/ptrace.c
downloadlinux-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
linux-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/ppc/kernel/ptrace.c')
-rw-r--r--arch/ppc/kernel/ptrace.c474
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;
+ }
+}