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-rw-r--r--arch/m68knommu/kernel/ptrace.c383
1 files changed, 383 insertions, 0 deletions
diff --git a/arch/m68knommu/kernel/ptrace.c b/arch/m68knommu/kernel/ptrace.c
new file mode 100644
index 000000000000..15cf79080b15
--- /dev/null
+++ b/arch/m68knommu/kernel/ptrace.c
@@ -0,0 +1,383 @@
+/*
+ * 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/smp_lock.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/config.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 < sizeof(regoff)/sizeof(regoff[0]))
+ 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 < sizeof(regoff)/sizeof(regoff[0]))
+ 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);
+}
+
+asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
+{
+ struct task_struct *child;
+ int ret;
+
+ lock_kernel();
+ ret = -EPERM;
+ 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 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 = 0;
+ if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
+ break;
+ ret = -EIO;
+ 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 ((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. */
+ 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 ((unsigned long) data > _NSIG)
+ 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;
+ }
+out_tsk:
+ put_task_struct(child);
+out:
+ unlock_kernel();
+ 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;
+ }
+}
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