On Tuesday 10 May 2016 17:47:26 Zhangjian wrote: > On 2016/5/10 16:36, Arnd Bergmann wrote: > > On Tuesday 10 May 2016 15:42:07 Zhangjian wrote: > >> On 2016/5/6 20:37, Yury Norov wrote: > > "include/uapi/asm-generic/posix_types.h" is uapi, we could not check > "ARCH_32BIT_OFF_T" here. Besides, the `__kernel_long_t` is long which > mean it is 32bit in ILP32. should we define something like x32? > ``` > diff --git a/arch/arm64/include/uapi/asm/posix_types.h b/arch/arm64/include/uapi/asm/posix_types.h > index 7985ff6..9baa8d3 100644 > --- a/arch/arm64/include/uapi/asm/posix_types.h > +++ b/arch/arm64/include/uapi/asm/posix_types.h glibc does not use the definition of __kernel_off_t, it has its own copy, so changing the kernel headers would do nothing. > @@ -5,6 +5,9 @@ typedef unsigned short __kernel_old_uid_t; > typedef unsigned short __kernel_old_gid_t; > #define __kernel_old_uid_t __kernel_old_uid_t > > +typedef long long __kernel_long_t; > +typedef unsigned long long __kernel_ulong_t; > + > #include <asm-generic/posix_types.h> > > #endif /* __ASM_POSIX_TYPES_H */u > ``` This would break all sorts of things, because __kernel_long_t/__kernel_ulong_t are not just used for off_t but also other things. > > On the other hand, glibc define it own off_t in "bits/types.h": > __STD_TYPE __OFF_T_TYPE __off_t; /* Type of file sizes and offsets. */ > __STD_TYPE __OFF64_T_TYPE __off64_t; /* Type of file sizes and offsets (LFS). */ > > in "sysdeps/unix/sysv/linux/aarch64/bits/typesizes.h": > #define __OFF_T_TYPE __SLONGWORD_TYPE > #define __OFF64_T_TYPE __SQUAD_TYPE > > If we define off_t as 64bit in glibc: > #define __OFF_T_TYPE __SQUAD_TYPE > > Should We need to align all the off_t syscall to 64bit syscall in > kernel? > Yes, this is the change that I think we need to make, along with the same change for __INO_T_TYPE and #define __OFF_T_MATCHES_OFF64_T 1 #define __INO_T_MATCHES_INO64_T 1 If I read the rest of the glibc headers right, that should be all we need to ensure that both off_t and off64_t match the __kernel_loff_t based syscalls. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
