UPSTREAM: arch: move SA_* definitions to generic headers

Most architectures with the exception of alpha, mips, parisc and
sparc use the same values for these flags. Move their definitions into
asm-generic/signal-defs.h and allow the architectures with non-standard
values to override them. Also, document the non-standard flag values
in order to make it easier to add new generic flags in the future.

A consequence of this change is that on powerpc and x86, the constants'
values aside from SA_RESETHAND change signedness from unsigned
to signed. This is not expected to impact realistic use of these
constants. In particular the typical use of the constants where they
are or'ed together and assigned to sa_flags (or another int variable)
would not be affected.

Signed-off-by: Peter Collingbourne <pcc@google.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Link: https://linux-review.googlesource.com/id/Ia3849f18b8009bf41faca374e701cdca36974528
Link: https://lkml.kernel.org/r/b6d0d1ec34f9ee93e1105f14f288fba5f89d1f24.1605235762.git.pcc@google.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
(cherry picked from commit 1d82b7898f2ad9cc414805aef23b99b742218f10)
Bug: 135772972
Change-Id: Ia3849f18b8009bf41faca374e701cdca36974528
diff --git a/arch/arm/include/uapi/asm/signal.h b/arch/arm/include/uapi/asm/signal.h
index 9b4185b..c9a3ea1 100644
--- a/arch/arm/include/uapi/asm/signal.h
+++ b/arch/arm/include/uapi/asm/signal.h
@@ -60,33 +60,12 @@ typedef unsigned long sigset_t;
 #define SIGSWI		32
 
 /*
- * SA_FLAGS values:
- *
- * SA_NOCLDSTOP		flag to turn off SIGCHLD when children stop.
- * SA_NOCLDWAIT		flag on SIGCHLD to inhibit zombies.
- * SA_SIGINFO		deliver the signal with SIGINFO structs
- * SA_THIRTYTWO		delivers the signal in 32-bit mode, even if the task 
- *			is running in 26-bit.
- * SA_ONSTACK		allows alternate signal stacks (see sigaltstack(2)).
- * SA_RESTART		flag to get restarting signals (which were the default long ago)
- * SA_NODEFER		prevents the current signal from being masked in the handler.
- * SA_RESETHAND		clears the handler when the signal is delivered.
- *
- * SA_ONESHOT and SA_NOMASK are the historical Linux names for the Single
- * Unix names RESETHAND and NODEFER respectively.
+ * SA_THIRTYTWO historically meant deliver the signal in 32-bit mode, even if
+ * the task is running in 26-bit. But since the kernel no longer supports
+ * 26-bit mode, the flag has no effect.
  */
-#define SA_NOCLDSTOP	0x00000001
-#define SA_NOCLDWAIT	0x00000002
-#define SA_SIGINFO	0x00000004
 #define SA_THIRTYTWO	0x02000000
 #define SA_RESTORER	0x04000000
-#define SA_ONSTACK	0x08000000
-#define SA_RESTART	0x10000000
-#define SA_NODEFER	0x40000000
-#define SA_RESETHAND	0x80000000
-
-#define SA_NOMASK	SA_NODEFER
-#define SA_ONESHOT	SA_RESETHAND
 
 #define MINSIGSTKSZ	2048
 #define SIGSTKSZ	8192