parisc: add skeleton syscall.h

Needed for lib/syscall.c when HAVE_ARCH_TRACEHOOK.

Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
diff --git a/arch/parisc/include/asm/syscall.h b/arch/parisc/include/asm/syscall.h
new file mode 100644
index 0000000..8bdfd2c
--- /dev/null
+++ b/arch/parisc/include/asm/syscall.h
@@ -0,0 +1,40 @@
+/* syscall.h */
+
+#ifndef _ASM_PARISC_SYSCALL_H_
+#define _ASM_PARISC_SYSCALL_H_
+
+#include <linux/err.h>
+#include <asm/ptrace.h>
+
+static inline long syscall_get_nr(struct task_struct *tsk,
+				  struct pt_regs *regs)
+{
+	return regs->gr[20];
+}
+
+static inline void syscall_get_arguments(struct task_struct *tsk,
+					 struct pt_regs *regs, unsigned int i,
+					 unsigned int n, unsigned long *args)
+{
+	BUG_ON(i);
+
+	switch (n) {
+	case 6:
+		args[5] = regs->gr[21];
+	case 5:
+		args[4] = regs->gr[22];
+	case 4:
+		args[3] = regs->gr[23];
+	case 3:
+		args[2] = regs->gr[24];
+	case 2:
+		args[1] = regs->gr[25];
+	case 1:
+		args[0] = regs->gr[26];
+		break;
+	default:
+		BUG();
+	}
+}
+
+#endif /*_ASM_PARISC_SYSCALL_H_*/