syscall overhaul part two - unify public and internal syscall interface

with this patch, the syscallN() functions are no longer needed; a
variadic syscall() macro allows syscalls with anywhere from 0 to 6
arguments to be made with a single macro name. also, manually casting
each non-integer argument with (long) is no longer necessary; the
casts are hidden in the macros.

some source files which depended on being able to define the old macro
SYSCALL_RETURNS_ERRNO have been modified to directly use __syscall()
instead of syscall(). references to SYSCALL_SIGSET_SIZE and SYSCALL_LL
have also been changed.

x86_64 has not been tested, and may need a follow-up commit to fix any
minor bugs/oversights.

2 files changed, 69 insertions, 2 deletions

diff --git a/arch/x86_64/bits/fcntl.h b/arch/x86_64/bits/fcntl.h
index 802c3d14..2487a308 100644
--- a/arch/x86_64/bits/fcntl.h
+++ b/arch/x86_64/bits/fcntl.h
@@ -14,12 +14,15 @@
 #define O_NOFOLLOW  0400000
 #define O_CLOEXEC  02000000
 
-#ifdef _GNU_SOURCE
-#define O_NDELAY O_NONBLOCK
+/* Extensions, but in the reserved namespace, so OK */
 #define O_ASYNC      020000
 #define O_DIRECT     040000
+#define O_LARGEFILE       0
 #define O_NOATIME  01000000
+#define O_NDELAY O_NONBLOCK
 #define F_DUPFD_CLOEXEC 1030
+
+#ifdef _GNU_SOURCE
 #define FAPPENT O_APPEND
 #define FFSYNC O_FSYNC
 #define FASYNC O_ASYNC
diff --git a/arch/x86_64/bits/syscall.h b/arch/x86_64/bits/syscall.h
index ca75019d..c6f12230 100644
--- a/arch/x86_64/bits/syscall.h
+++ b/arch/x86_64/bits/syscall.h
@@ -1,3 +1,67 @@
+#define __SYSCALL_LL(x) (x)
+
+static inline long __syscall0(long __n)
+{
+	unsigned long __ret;
+	__asm__ __volatile__ ("syscall" : "=a"(__ret) : "a"(__n) : "rcx", "r11", "memory");
+	return __ret;
+}
+
+static inline long __syscall1(long __n, long __a1)
+{
+	unsigned long __ret;
+	__asm__ __volatile__ ("syscall" : "=a"(__ret) : "a"(__n), "D"(__a1) : "rcx", "r11", "memory");
+	return __ret;
+}
+
+static inline long __syscall2(long __n, long __a1, long __a2)
+{
+	unsigned long __ret;
+	__asm__ __volatile__ ("syscall" : "=a"(__ret) : "a"(__n), "D"(__a1), "S"(__a2)
+						  : "rcx", "r11", "memory");
+	return __ret;
+}
+
+static inline long __syscall3(long __n, long __a1, long __a2, long __a3)
+{
+	unsigned long __ret;
+	__asm__ __volatile__ ("syscall" : "=a"(__ret) : "a"(__n), "D"(__a1), "S"(__a2),
+						  "d"(__a3) : "rcx", "r11", "memory");
+	return __ret;
+}
+
+static inline long __syscall4(long __n, long __a1, long __a2, long __a3, long __a4)
+{
+	unsigned long __ret;
+	register long __r10 __asm__("r10") = __a4;
+	__asm__ __volatile__ ("syscall" : "=a"(__ret) : "a"(__n), "D"(__a1), "S"(__a2),
+						  "d"(__a3), "r"(__r10): "rcx", "r11", "memory");
+	return __ret;
+}
+
+static inline long __syscall5(long __n, long __a1, long __a2, long __a3, long __a4, long __a5)
+{
+	unsigned long __ret;
+	register long __r10 __asm__("r10") = __a4;
+	register long__ r8 __asm__("r8") = __a5;
+	__asm__ __volatile__ ("syscall" : "=a"(__ret) : "a"(__n), "D"(__a1), "S"(__a2),
+						  "d"(__a3), "r"(__r10), "r"(__r8) : "rcx", "r11", "memory");
+	return __ret;
+}
+
+static inline long __syscall6(long __n, long __a1, long __a2, long __a3, long __a4, long __a5, long __a6)
+{
+	unsigned long __ret;
+	register long __r10 __asm__("r10") = __a4;
+	register long __r8 __asm__("r8") = __a5;
+	register long __r9 __asm__("r9") = __a6;
+	__asm__ __volatile__ ("syscall" : "=a"(__ret) : "a"(__n), "D"(__a1), "S"(__a2),
+						  "d"(__a3), "r"(__r10), "r"(__r8), "r"(__r9) : "rcx", "r11", "memory");
+	return __ret;
+}
+
+#define __socketcall(nm, a, b, c, d, e, f) syscall(__NR_##nm, a, b, c, d, e, f)
+
 #define __NR_read				0
 #define __NR_write				1
 #define __NR_open				2