x86/headers: Move the 'struct sigcontext' definitions into the UAPI header

Our goal is to eliminate the duplicate struct sigcontext_ia32
definition, so move the kernel's primary sigcontext type into
the UAPI header, defining these two variants:

	struct sigcontext_32
	struct sigcontext_64

... and map them to 'struct sigcontext'.

Acked-by: Mikko Rapeli <mikko.rapeli@iki.fi>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1441438363-9999-11-git-send-email-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/sigcontext.h

@@ -3,77 +3,4 @@
 
 #include <uapi/asm/sigcontext.h>
 
-#ifdef __i386__
-struct sigcontext {
-	__u16				 gs, __gsh;
-	__u16				 fs, __fsh;
-	__u16				 es, __esh;
-	__u16				 ds, __dsh;
-	__u32				 di;
-	__u32				 si;
-	__u32				 bp;
-	__u32				 sp;
-	__u32				 bx;
-	__u32				 dx;
-	__u32				 cx;
-	__u32				 ax;
-	__u32				 trapno;
-	__u32				 err;
-	__u32				 ip;
-	__u16				 cs, __csh;
-	__u32				 flags;
-	__u32				 sp_at_signal;
-	__u16				 ss, __ssh;
-
-	/*
-	 * fpstate is really (struct _fpstate *) or (struct _xstate *)
-	 * depending on the FP_XSTATE_MAGIC1 encoded in the SW reserved
-	 * bytes of (struct _fpstate) and FP_XSTATE_MAGIC2 present at the end
-	 * of extended memory layout. See comments at the definition of
-	 * (struct _fpx_sw_bytes)
-	 */
-	void __user			*fpstate; /* Zero when no FPU/extended context */
-	__u32				 oldmask;
-	__u32				 cr2;
-};
-#else /* __x86_64__: */
-struct sigcontext {
-	__u64				 r8;
-	__u64				 r9;
-	__u64				 r10;
-	__u64				 r11;
-	__u64				 r12;
-	__u64				 r13;
-	__u64				 r14;
-	__u64				 r15;
-	__u64				 di;
-	__u64				 si;
-	__u64				 bp;
-	__u64				 bx;
-	__u64				 dx;
-	__u64				 ax;
-	__u64				 cx;
-	__u64				 sp;
-	__u64				 ip;
-	__u64				 flags;
-	__u16				 cs;
-	__u16				 gs;
-	__u16				 fs;
-	__u16				 __pad0;
-	__u64				 err;
-	__u64				 trapno;
-	__u64				 oldmask;
-	__u64				 cr2;
-
-	/*
-	 * fpstate is really (struct _fpstate *) or (struct _xstate *)
-	 * depending on the FP_XSTATE_MAGIC1 encoded in the SW reserved
-	 * bytes of (struct _fpstate) and FP_XSTATE_MAGIC2 present at the end
-	 * of extended memory layout. See comments at the definition of
-	 * (struct _fpx_sw_bytes)
-	 */
-	void __user			*fpstate; /* Zero when no FPU/extended context */
-	__u64				 reserved1[8];
-};
-#endif /* !__x86_64__ */
 #endif /* _ASM_X86_SIGCONTEXT_H */

arch/x86/include/uapi/asm/sigcontext.h

@@ -190,6 +190,89 @@ struct _xstate {
 	/* New processor state extensions go here: */
 };
 
+struct sigcontext_32 {
+	__u16				gs, __gsh;
+	__u16				fs, __fsh;
+	__u16				es, __esh;
+	__u16				ds, __dsh;
+	__u32				di;
+	__u32				si;
+	__u32				bp;
+	__u32				sp;
+	__u32				bx;
+	__u32				dx;
+	__u32				cx;
+	__u32				ax;
+	__u32				trapno;
+	__u32				err;
+	__u32				ip;
+	__u16				cs, __csh;
+	__u32				flags;
+	__u32				sp_at_signal;
+	__u16				ss, __ssh;
+
+	/*
+	 * fpstate is really (struct _fpstate *) or (struct _xstate *)
+	 * depending on the FP_XSTATE_MAGIC1 encoded in the SW reserved
+	 * bytes of (struct _fpstate) and FP_XSTATE_MAGIC2 present at the end
+	 * of extended memory layout. See comments at the definition of
+	 * (struct _fpx_sw_bytes)
+	 */
+	void __user			*fpstate; /* Zero when no FPU/extended context */
+	__u32				oldmask;
+	__u32				cr2;
+};
+
+struct sigcontext_64 {
+	__u64				r8;
+	__u64				r9;
+	__u64				r10;
+	__u64				r11;
+	__u64				r12;
+	__u64				r13;
+	__u64				r14;
+	__u64				r15;
+	__u64				di;
+	__u64				si;
+	__u64				bp;
+	__u64				bx;
+	__u64				dx;
+	__u64				ax;
+	__u64				cx;
+	__u64				sp;
+	__u64				ip;
+	__u64				flags;
+	__u16				cs;
+	__u16				gs;
+	__u16				fs;
+	__u16				__pad0;
+	__u64				err;
+	__u64				trapno;
+	__u64				oldmask;
+	__u64				cr2;
+
+	/*
+	 * fpstate is really (struct _fpstate *) or (struct _xstate *)
+	 * depending on the FP_XSTATE_MAGIC1 encoded in the SW reserved
+	 * bytes of (struct _fpstate) and FP_XSTATE_MAGIC2 present at the end
+	 * of extended memory layout. See comments at the definition of
+	 * (struct _fpx_sw_bytes)
+	 */
+	void __user			*fpstate; /* Zero when no FPU/extended context */
+	__u64				reserved1[8];
+};
+
+/*
+ * Create the real 'struct sigcontext' type:
+ */
+#ifdef __KERNEL__
+# ifdef __i386__
+#  define sigcontext sigcontext_32
+# else
+#  define sigcontext sigcontext_64
+# endif
+#endif
+
 /*
  * The old user-space sigcontext definition, just in case user-space still
  * relies on it. The kernel definition (in asm/sigcontext.h) has unified