As suggested by Al, we can use the generic sys_pipe() instead of

xtensa_pipe() for xtensa.
Signed-off-by: WANG Cong <amwang@redhat.com>
Reviewed-by: Johannes Weiner <jw@emlix.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/xtensa/include/asm/syscall.h

@@ -12,7 +12,6 @@ struct pt_regs;
 struct sigaction;
 asmlinkage long xtensa_execve(char*, char**, char**, struct pt_regs*);
 asmlinkage long xtensa_clone(unsigned long, unsigned long, struct pt_regs*);
-asmlinkage long xtensa_pipe(int __user *);
 asmlinkage long xtensa_mmap2(unsigned long, unsigned long, unsigned long,
     			     unsigned long, unsigned long, unsigned long);
 asmlinkage long xtensa_ptrace(long, long, long, long);

arch/xtensa/include/asm/unistd.h

@@ -94,7 +94,7 @@ __SYSCALL( 35, sys_readlink, 3)
 #define __NR_mknod 				 36
 __SYSCALL( 36, sys_mknod, 3)
 #define __NR_pipe 				 37
-__SYSCALL( 37, xtensa_pipe, 1)
+__SYSCALL( 37, sys_pipe, 1)
 #define __NR_unlink 				 38
 __SYSCALL( 38, sys_unlink, 1)
 #define __NR_rmdir 				 39

arch/xtensa/kernel/syscall.c

@@ -39,24 +39,6 @@ syscall_t sys_call_table[__NR_syscall_count] /* FIXME __cacheline_aligned */= {
 #include <asm/unistd.h>
 };
 
-/*
- * xtensa_pipe() is the normal C calling standard for creating a pipe. It's not
- * the way unix traditional does this, though.
- */
-
-asmlinkage long xtensa_pipe(int __user *userfds)
-{
-	int fd[2];
-	int error;
-
-	error = do_pipe_flags(fd, 0);
-	if (!error) {
-		if (copy_to_user(userfds, fd, 2 * sizeof(int)))
-			error = -EFAULT;
-	}
-	return error;
-}
-
 
 asmlinkage long xtensa_mmap2(unsigned long addr, unsigned long len,
    			     unsigned long prot, unsigned long flags,