On Sun, Jan 30, 2022 at 6:41 AM Arnd Bergmann <arnd@xxxxxxxx> wrote: > > > Implement compat sys_call_table and some system call functions: > > truncate64, ftruncate64, fallocate, pread64, pwrite64, > > sync_file_range, readahead, fadvise64_64 which need argument > > translation. > > > > Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx> > > Signed-off-by: Guo Ren <guoren@xxxxxxxxxx> > > Cc: Arnd Bergmann <arnd@xxxxxxxx> > > This all looks really good, but I would change one detail: > > > +#ifndef compat_arg_u64 > > +#define compat_arg_u64(name) u32 name##_lo, u32 name##_hi > > +#define compat_arg_u64_dual(name) u32, name##_lo, u32, name##_hi > > +#define compat_arg_u64_glue(name) (((u64)name##_hi << 32) | \ > > + ((u64)name##_lo & 0xffffffffUL)) > > +#endif > > I would make these endian-specific, and reverse them on big-endian > architectures. That way it > should be possible to share them across all compat architectures > without needing the override > option. I hope it could be another patch. Because it's not clear to _LITTLE_ENDIAN definition in archs. eg: Names could be __ORDER_LITTLE_ENDIAN__ CPU_LITTLE_ENDIAN SYS_SUPPORTS_LITTLE_ENDIAN __LITTLE_ENDIAN riscv is little-endian, but no any LITTLE_ENDIAN definition. So let's keep them in the patch, first, Thx > > Arnd -- Best Regards Guo Ren ML: https://lore.kernel.org/linux-csky/