BACKPORT: ARM: wire up getrandom syscall

Clean cherry pick of eb64525.

Add the new getrandom syscall for ARM.

Signed-off-by: Russell King <[email protected]>

Bug: http://b/29621447
Change-Id: I6d50b57f3a61fbf9102c69103b9a5b7ebf239860
(cherry picked from commit eb64525)

Author: Russell King

arch/arm/include/asm/unistd.h

@@ -15,7 +15,17 @@
 
 #include <uapi/asm/unistd.h>
 
-#define __NR_syscalls  (384)
+/*
+ * This may need to be greater than __NR_last_syscall+1 in order to
+ * account for the padding in the syscall table
+ */
+#define __NR_syscalls  (388)
+
+/*
+ * *NOTE*: This is a ghost syscall private to the kernel.  Only the
+ * __kuser_cmpxchg code in entry-armv.S should be aware of its
+ * existence.  Don't ever use this from user code.
+ */
 #define __ARM_NR_cmpxchg		(__ARM_NR_BASE+0x00fff0)
 
 #define __ARCH_WANT_STAT64

arch/arm/include/uapi/asm/unistd.h

@@ -408,15 +408,9 @@
 #define __NR_finit_module		(__NR_SYSCALL_BASE+379)
 #define __NR_sched_setattr		(__NR_SYSCALL_BASE+380)
 #define __NR_sched_getattr		(__NR_SYSCALL_BASE+381)
-/* Reserve for later
 #define __NR_renameat2			(__NR_SYSCALL_BASE+382)
-*/
 #define __NR_seccomp			(__NR_SYSCALL_BASE+383)
-
-/*
- * This may need to be greater than __NR_last_syscall+1 in order to
- * account for the padding in the syscall table
- */
+#define __NR_getrandom			(__NR_SYSCALL_BASE+384)
 
 /*
  * The following SWIs are ARM private.

arch/arm/kernel/calls.S

@@ -391,9 +391,9 @@
 		CALL(sys_finit_module)
 /* 380 */	CALL(sys_sched_setattr)
 		CALL(sys_sched_getattr)
-		CALL(sys_ni_syscall)		/* reserved sys_renameat2     */
+		CALL(sys_renameat2)
 		CALL(sys_seccomp)
-
+		CALL(sys_getrandom)
 #ifndef syscalls_counted
 .equ syscalls_padding, ((NR_syscalls + 3) & ~3) - NR_syscalls
 #define syscalls_counted