Introduce fixed sys_sync_file_range2() syscall, implement on PowerPC and ARM

Not all the world is an i386. Many architectures need 64-bit arguments to be aligned in suitable pairs of registers, and the original sys_sync_file_range(int, loff_t, loff_t, int) was therefore wasting an argument register for padding after the first integer. Since we don't normally have more than 6 arguments for system calls, that left no room for the final argument on some architectures. Fix this by introducing sys_sync_file_range2(int, int, loff_t, loff_t) which all fits nicely. In fact, ARM already had that, but called it sys_arm_sync_file_range. Move it to fs/sync.c and rename it, then implement the needed compatibility routine. And stop the missing syscall check from bitching about the absence of sys_sync_file_range() if we've implemented sys_sync_file_range2() instead. Tested on PPC32 and with 32-bit and 64-bit userspace on PPC64.

DWDavid Woodhouse committed 19 years ago