Re: [RFC5 PATCH v6 00/21] ILP32 for ARM64
From: Arnd Bergmann
Date: Tue Mar 29 2016 - 09:28:25 EST
On Tuesday 29 March 2016 21:21:49 Zhangjian wrote:
> >>> Then we could remove the __USE_FILE_OFFSET64 in stat.h and fcnt.h in
> >>> aarch64. And truncate and ftruncate is same as truncate64 and
> >>> ftruncate64.
> >> I don't know what the glibc developers prefer, but I think the
> >> result needs to be something like that: either __OFF_T_TYPE is
> >> defined as you write above as a 64-bit type, or the user-visible
> >> off_t typedef unconditionally uses __OFF64_T_TYPE rather than
> >> __OFF_T_TYPE.
> > I'm not the glibc developer as well, but I think it's OK.
> IIUC, it is usually what glibc does.
> If we want to define off_t to 64bit in ilp32, the follow syscall may
> need to define as non-compat too:
I'm not following here. Do you mean in the kernel or in glibc?
In the kernel, the list of syscalls is fine, because we already only
provide syscalls passing loff_t as I said, and that is 64-bit.
In glibc, I think we need to define fewer entry points, not more.
Instead of having both lseek and lseek64, only one of them should
be provided, and that should always take a 64-bit offset, calling
into the kernel with the _llseek syscall entry.