+/*
+ * Functions that implement syscalls.
+ */
+unsigned long sys_mmap(unsigned long addr, size_t len, unsigned long prot,
+ unsigned long flags, unsigned long fd, off_t offset);
+unsigned long sys_mmap2(unsigned long addr, size_t len,
+ unsigned long prot, unsigned long flags,
+ unsigned long fd, unsigned long pgoff);
+struct pt_regs;
+int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
+ unsigned long a3, unsigned long a4, unsigned long a5,
+ struct pt_regs *regs);
+int sys_clone(unsigned long clone_flags, unsigned long usp,
+ int __user *parent_tidp, void __user *child_threadptr,
+ int __user *child_tidp, int p6, struct pt_regs *regs);
+int sys_fork(unsigned long p1, unsigned long p2, unsigned long p3,
+ unsigned long p4, unsigned long p5, unsigned long p6,
+ struct pt_regs *regs);
+int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3,
+ unsigned long p4, unsigned long p5, unsigned long p6,
+ struct pt_regs *regs);
+int sys_pipe(int __user *fildes);
+struct sigaction;
+long sys_rt_sigaction(int sig, const struct sigaction __user *act,
+ struct sigaction __user *oact, size_t sigsetsize);
+