[POWERPC] Make syscall restart code more common

This patch moves the code in signal_32.c and signal_64.c for handling
syscall restart into a common signal.c file and converge around a single
implementation that is based on the 32 bits one, using trap, ccr
and r3 rather than the special "result" field for deciding what to do.

The "result" field is now pretty much deprecated. We still set it for
the sake of whatever might rely on it in userland but we no longer use
it's content.

This, along with a previous patch that enables ptracers to write to
"trap" and "orig_r3" should allow gdb to properly handle syscall
restarting.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 16 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
new file mode 100644
index 000000000000..1e8dfb8620ad
--- /dev/null
+++ b/arch/powerpc/kernel/signal.h
@@ -0,0 +1,16 @@
+/*
+ *    Copyright (c) 2007 Benjamin Herrenschmidt, IBM Coproration
+ *    Extracted from signal_32.c and signal_64.c
+ *
+ * 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.
+ */
+
+#ifndef _POWERPC_ARCH_SIGNAL_H
+#define _POWERPC_ARCH_SIGNAL_H
+
+extern void check_syscall_restart(struct pt_regs *regs, struct k_sigaction *ka,
+                                  int has_handler);
+
+#endif  /* _POWERPC_ARCH_SIGNAL_H */