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-rw-r--r--arch/sh/kernel/ptrace.c320
1 files changed, 320 insertions, 0 deletions
diff --git a/arch/sh/kernel/ptrace.c b/arch/sh/kernel/ptrace.c
new file mode 100644
index 00000000000..1b0dfb4d8ea
--- /dev/null
+++ b/arch/sh/kernel/ptrace.c
@@ -0,0 +1,320 @@
+/*
+ * linux/arch/sh/kernel/ptrace.c
+ *
+ * Original x86 implementation:
+ * By Ross Biro 1/23/92
+ * edited by Linus Torvalds
+ *
+ * SuperH version: Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka
+ *
+ */
+
+#include <linux/config.h>
+#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/slab.h>
+#include <linux/security.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/mmu_context.h>
+
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+/*
+ * This routine will get a word off of the process kernel stack.
+ */
+static inline int get_stack_long(struct task_struct *task, int offset)
+{
+ unsigned char *stack;
+
+ stack = (unsigned char *)
+ task->thread_info + THREAD_SIZE - sizeof(struct pt_regs)
+#ifdef CONFIG_SH_DSP
+ - sizeof(struct pt_dspregs)
+#endif
+ - sizeof(unsigned long);
+ stack += offset;
+ return (*((int *)stack));
+}
+
+/*
+ * This routine will put a word on the process kernel stack.
+ */
+static inline int put_stack_long(struct task_struct *task, int offset,
+ unsigned long data)
+{
+ unsigned char *stack;
+
+ stack = (unsigned char *)
+ task->thread_info + THREAD_SIZE - sizeof(struct pt_regs)
+#ifdef CONFIG_SH_DSP
+ - sizeof(struct pt_dspregs)
+#endif
+ - sizeof(unsigned long);
+ stack += offset;
+ *(unsigned long *) stack = data;
+ return 0;
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure single step bits etc are not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ /* nothing to do.. */
+}
+
+asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
+{
+ struct task_struct *child;
+ struct user * dummy = NULL;
+ int ret;
+
+ lock_kernel();
+ ret = -EPERM;
+ 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 *) 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;
+
+ if (addr < sizeof(struct pt_regs))
+ tmp = get_stack_long(child, addr);
+ else if (addr >= (long) &dummy->fpu &&
+ addr < (long) &dummy->u_fpvalid) {
+ if (!tsk_used_math(child)) {
+ if (addr == (long)&dummy->fpu.fpscr)
+ tmp = FPSCR_INIT;
+ else
+ tmp = 0;
+ } else
+ tmp = ((long *)&child->thread.fpu)
+ [(addr - (long)&dummy->fpu) >> 2];
+ } else if (addr == (long) &dummy->u_fpvalid)
+ tmp = !!tsk_used_math(child);
+ else
+ tmp = 0;
+ 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;
+
+ if (addr < sizeof(struct pt_regs))
+ ret = put_stack_long(child, addr, data);
+ else if (addr >= (long) &dummy->fpu &&
+ addr < (long) &dummy->u_fpvalid) {
+ set_stopped_child_used_math(child);
+ ((long *)&child->thread.fpu)
+ [(addr - (long)&dummy->fpu) >> 2] = data;
+ ret = 0;
+ } else if (addr == (long) &dummy->u_fpvalid) {
+ conditional_stopped_child_used_math(data, child);
+ 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;
+ 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;
+ wake_up_process(child);
+ break;
+ }
+
+ case PTRACE_SINGLESTEP: { /* set the trap flag. */
+ long pc;
+ struct pt_regs *dummy = NULL;
+
+ ret = -EIO;
+ if ((unsigned long) data > _NSIG)
+ break;
+ clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+ if ((child->ptrace & PT_DTRACE) == 0) {
+ /* Spurious delayed TF traps may occur */
+ child->ptrace |= PT_DTRACE;
+ }
+
+ pc = get_stack_long(child, (long)&dummy->pc);
+
+ /* Next scheduling will set up UBC */
+ if (child->thread.ubc_pc == 0)
+ ubc_usercnt += 1;
+ child->thread.ubc_pc = pc;
+
+ 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;
+
+#ifdef CONFIG_SH_DSP
+ case PTRACE_GETDSPREGS: {
+ unsigned long dp;
+
+ ret = -EIO;
+ dp = ((unsigned long) child) + THREAD_SIZE -
+ sizeof(struct pt_dspregs);
+ if (*((int *) (dp - 4)) == SR_FD) {
+ copy_to_user(addr, (void *) dp,
+ sizeof(struct pt_dspregs));
+ ret = 0;
+ }
+ break;
+ }
+
+ case PTRACE_SETDSPREGS: {
+ unsigned long dp;
+ int i;
+
+ ret = -EIO;
+ dp = ((unsigned long) child) + THREAD_SIZE -
+ sizeof(struct pt_dspregs);
+ if (*((int *) (dp - 4)) == SR_FD) {
+ copy_from_user((void *) dp, addr,
+ sizeof(struct pt_dspregs));
+ ret = 0;
+ }
+ break;
+ }
+#endif
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+out_tsk:
+ put_task_struct(child);
+out:
+ unlock_kernel();
+ return ret;
+}
+
+asmlinkage void do_syscall_trace(void)
+{
+ struct task_struct *tsk = current;
+
+ if (!test_thread_flag(TIF_SYSCALL_TRACE))
+ return;
+ if (!(tsk->ptrace & PT_PTRACED))
+ return;
+ /* the 0x80 provides a way for the tracing parent to distinguish
+ between a syscall stop and SIGTRAP delivery */
+ 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 (tsk->exit_code) {
+ send_sig(tsk->exit_code, tsk, 1);
+ tsk->exit_code = 0;
+ }
+}