signal: Define __ARCH_HAS_SA_RESTORER so we know whether to clear sa_restorer

Vaguely based on upstream commit 574c4866e33d 'consolidate kernel-side
struct sigaction declarations'.

flush_signal_handlers() needs to know whether sigaction::sa_restorer
is defined, not whether SA_RESTORER is defined.  Define the
__ARCH_HAS_SA_RESTORER macro to indicate this.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/arm/include/asm/signal.h b/arch/arm/include/asm/signal.h
index 43ba0fb..559ee24 100644
--- a/arch/arm/include/asm/signal.h
+++ b/arch/arm/include/asm/signal.h
@@ -127,6 +127,7 @@
 	__sigrestore_t sa_restorer;
 	sigset_t sa_mask;		/* mask last for extensibility */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 struct k_sigaction {
 	struct sigaction sa;
diff --git a/arch/avr32/include/asm/signal.h b/arch/avr32/include/asm/signal.h
index 8790dfc..e6952a0 100644
--- a/arch/avr32/include/asm/signal.h
+++ b/arch/avr32/include/asm/signal.h
@@ -128,6 +128,7 @@
 	__sigrestore_t sa_restorer;
 	sigset_t sa_mask;		/* mask last for extensibility */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 struct k_sigaction {
 	struct sigaction sa;
diff --git a/arch/cris/include/asm/signal.h b/arch/cris/include/asm/signal.h
index ea6af9a..057fea2 100644
--- a/arch/cris/include/asm/signal.h
+++ b/arch/cris/include/asm/signal.h
@@ -122,6 +122,7 @@
 	void (*sa_restorer)(void);
 	sigset_t sa_mask;		/* mask last for extensibility */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 struct k_sigaction {
 	struct sigaction sa;
diff --git a/arch/h8300/include/asm/signal.h b/arch/h8300/include/asm/signal.h
index fd8b66e..8695707 100644
--- a/arch/h8300/include/asm/signal.h
+++ b/arch/h8300/include/asm/signal.h
@@ -121,6 +121,7 @@
 	void (*sa_restorer)(void);
 	sigset_t sa_mask;		/* mask last for extensibility */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 struct k_sigaction {
 	struct sigaction sa;
diff --git a/arch/m32r/include/asm/signal.h b/arch/m32r/include/asm/signal.h
index b2eeb0d..802d561 100644
--- a/arch/m32r/include/asm/signal.h
+++ b/arch/m32r/include/asm/signal.h
@@ -123,6 +123,7 @@
 	__sigrestore_t sa_restorer;
 	sigset_t sa_mask;		/* mask last for extensibility */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 struct k_sigaction {
 	struct sigaction sa;
diff --git a/arch/m68k/include/asm/signal.h b/arch/m68k/include/asm/signal.h
index 93fe83e..a20ae63 100644
--- a/arch/m68k/include/asm/signal.h
+++ b/arch/m68k/include/asm/signal.h
@@ -119,6 +119,7 @@
 	__sigrestore_t sa_restorer;
 	sigset_t sa_mask;		/* mask last for extensibility */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 struct k_sigaction {
 	struct sigaction sa;
diff --git a/arch/mn10300/include/asm/signal.h b/arch/mn10300/include/asm/signal.h
index 1865d72..eecaa76 100644
--- a/arch/mn10300/include/asm/signal.h
+++ b/arch/mn10300/include/asm/signal.h
@@ -131,6 +131,7 @@
 	__sigrestore_t sa_restorer;
 	sigset_t sa_mask;		/* mask last for extensibility */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 struct k_sigaction {
 	struct sigaction sa;
diff --git a/arch/powerpc/include/asm/signal.h b/arch/powerpc/include/asm/signal.h
index 3eb13be..ec63a0a 100644
--- a/arch/powerpc/include/asm/signal.h
+++ b/arch/powerpc/include/asm/signal.h
@@ -109,6 +109,7 @@
 	__sigrestore_t sa_restorer;
 	sigset_t sa_mask;		/* mask last for extensibility */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 struct k_sigaction {
 	struct sigaction sa;
diff --git a/arch/s390/include/asm/signal.h b/arch/s390/include/asm/signal.h
index cdf5cb2..c872626 100644
--- a/arch/s390/include/asm/signal.h
+++ b/arch/s390/include/asm/signal.h
@@ -131,6 +131,7 @@
         void (*sa_restorer)(void);
         sigset_t sa_mask;               /* mask last for extensibility */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 struct k_sigaction {
         struct sigaction sa;
diff --git a/arch/sparc/include/asm/signal.h b/arch/sparc/include/asm/signal.h
index aa42fe3..d07beb3 100644
--- a/arch/sparc/include/asm/signal.h
+++ b/arch/sparc/include/asm/signal.h
@@ -192,6 +192,7 @@
 	unsigned long		sa_flags;
 	void			(*sa_restorer)(void);  /* not used by Linux/SPARC yet */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 typedef struct sigaltstack {
 	void			__user *ss_sp;
diff --git a/arch/x86/include/asm/signal.h b/arch/x86/include/asm/signal.h
index 598457c..6cbc795 100644
--- a/arch/x86/include/asm/signal.h
+++ b/arch/x86/include/asm/signal.h
@@ -125,6 +125,8 @@
 extern void do_notify_resume(struct pt_regs *, void *, __u32);
 # endif /* __KERNEL__ */
 
+#define __ARCH_HAS_SA_RESTORER
+
 #ifdef __i386__
 # ifdef __KERNEL__
 struct old_sigaction {
diff --git a/arch/xtensa/include/asm/signal.h b/arch/xtensa/include/asm/signal.h
index 633ba73..75edf8a 100644
--- a/arch/xtensa/include/asm/signal.h
+++ b/arch/xtensa/include/asm/signal.h
@@ -133,6 +133,7 @@
 	void (*sa_restorer)(void);
 	sigset_t sa_mask;		/* mask last for extensibility */
 };
+#define __ARCH_HAS_SA_RESTORER
 
 struct k_sigaction {
 	struct sigaction sa;
diff --git a/include/asm-generic/signal.h b/include/asm-generic/signal.h
index 555c0ae..743f7a5 100644
--- a/include/asm-generic/signal.h
+++ b/include/asm-generic/signal.h
@@ -99,6 +99,10 @@
 
 #include <asm-generic/signal-defs.h>
 
+#ifdef SA_RESTORER
+#define __ARCH_HAS_SA_RESTORER
+#endif
+
 struct sigaction {
 	__sighandler_t sa_handler;
 	unsigned long sa_flags;