m68knommu: use generic ptrace_resume code

Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT,
PTRACE_KILL and PTRACE_SINGLESTEP.  m68knommu already defines the
nessecary user_enable_single_step and user_disable_single_step functions
for this.

Also the TIF_SYSCALL_TRACE thread flag is now cleared on PTRACE_KILL which
it previously wasn't which is consistent with all architectures using the
modern ptrace code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/m68knommu/kernel/ptrace.c

@@ -190,62 +190,6 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 			}
 			break;
 
-		case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
-		case PTRACE_CONT: { /* restart after signal. */
-			long tmp;
-
-			ret = -EIO;
-			if (!valid_signal(data))
-				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 (!valid_signal(data))
-				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_GETREGS: { /* Get all gp regs from the child. */
 		  	int i;
 			unsigned long tmp;