[PATCH 4d] utrace: avr32 ptrace compatibility

From: Haavard Skinnemoen <hskinnemoen@atmel.com>

Rip out most of the ptrace code for AVR32 and replace it with the much
nicer utrace stuff.  It builds in all possible combinations of
CONFIG_UTRACE and CONFIG_PTRACE, and it seems to work as far as I've tested
it with strace and some simple debugging with gdb.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Roland McGrath <roland@redhat.com>

---

 arch/avr32/kernel/ptrace.c |  107 +++++++-------------------------------------
 1 files changed, 18 insertions(+), 89 deletions(-)

--- linux-2.6/arch/avr32/kernel/ptrace.c
+++ linux-2.6/arch/avr32/kernel/ptrace.c
@@ -78,115 +78,44 @@ const struct utrace_regset_view *utrace_
 }
 #endif /* CONFIG_UTRACE */
 
+#ifdef CONFIG_PTRACE
 
-#if 0
-long arch_ptrace(struct task_struct *child, long request, long addr, long data)
+static const struct ptrace_layout_segment avr32_uarea[] = {
+	{ 0, ELF_NGREG * sizeof(long), 0, 0 },
+	{ 0, 0, -1, 0 },
+};
+
+int arch_ptrace(long *request, struct task_struct *child,
+		struct utrace_attached_engine *engine,
+		unsigned long addr, unsigned long data, long *val)
 {
-	unsigned long tmp;
-	int ret;
-
 	pr_debug("arch_ptrace(%ld, %d, %#lx, %#lx)\n",
-		 request, child->pid, addr, data);
+		 *request, child->pid, addr, data);
 
 	pr_debug("ptrace: Enabling monitor mode...\n");
 	__mtdr(DBGREG_DC, __mfdr(DBGREG_DC) | DC_MM | DC_DBE);
 
-	switch (request) {
-	/* Read the word at location addr in the child process */
-	case PTRACE_PEEKTEXT:
-	case PTRACE_PEEKDATA:
-		ret = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
-		if (ret == sizeof(tmp))
-			ret = put_user(tmp, (unsigned long __user *)data);
-		else
-			ret = -EIO;
-		break;
-
+	switch (*request) {
 	case PTRACE_PEEKUSR:
-		ret = ptrace_read_user(child, addr,
-				       (unsigned long __user *)data);
-		break;
-
-	/* Write the word in data at location addr */
-	case PTRACE_POKETEXT:
-	case PTRACE_POKEDATA:
-		ret = access_process_vm(child, addr, &data, sizeof(data), 1);
-		if (ret == sizeof(data))
-			ret = 0;
-		else
-			ret = -EIO;
-		break;
+		return ptrace_peekusr(child, engine, avr32_uarea, addr, data);
 
 	case PTRACE_POKEUSR:
-		ret = ptrace_write_user(child, addr, data);
-		break;
-
-	/* continue and stop at next (return from) syscall */
-	case PTRACE_SYSCALL:
-	/* restart after signal */
-	case PTRACE_CONT:
-		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;
-		/* XXX: Are we sure no breakpoints are active here? */
-		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)
-			break;
-		child->exit_code = SIGKILL;
-		wake_up_process(child);
-		break;
-
-	/*
-	 * execute single instruction.
-	 */
-	case PTRACE_SINGLESTEP:
-		ret = -EIO;
-		if (!valid_signal(data))
-			break;
-		clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
-		ptrace_single_step(child);
-		child->exit_code = data;
-		wake_up_process(child);
-		ret = 0;
-		break;
-
-	/* Detach a process that was attached */
-	case PTRACE_DETACH:
-		ret = ptrace_detach(child, data);
+		return ptrace_pokeusr(child, engine, avr32_uarea, addr, data);
 		break;
 
 	case PTRACE_GETREGS:
-		ret = ptrace_getregs(child, (void __user *)data);
+		return ptrace_whole_regset(child, engine, data, 0, 0);
 		break;
 
 	case PTRACE_SETREGS:
-		ret = ptrace_setregs(child, (const void __user *)data);
-		break;
-
-	default:
-		ret = ptrace_request(child, request, addr, data);
+		return ptrace_whole_regset(child, engine, data, 0, 1);
 		break;
 	}
 
-	pr_debug("sys_ptrace returning %d (DC = 0x%08lx)\n", ret, __mfdr(DBGREG_DC));
-	return ret;
+	return -ENOSYS;
 }
-#endif
+#endif /* CONFIG_PTRACE */
+#endif /* CONFIG_UTRACE */
 
 asmlinkage void syscall_trace(struct pt_regs *regs, int is_exit)
 {