Re: [RFC5 PATCH v6 00/21] ILP32 for ARM64

From: Zhangjian (Bamvor)
Date: Tue Mar 29 2016 - 09:23:51 EST

Hi, Yury

On 2016/3/29 20:01, Yury Norov wrote:
On Tue, Mar 29, 2016 at 12:58:25PM +0200, Arnd Bergmann wrote:
On Saturday 26 March 2016 20:36:43 Zhangjian wrote:
Hi, Arnd

On 2016/3/21 17:43, Arnd Bergmann wrote:
On Monday 21 March 2016 10:07:49 Andreas Schwab wrote:
This patch may fix a few LTP tests.

Thanks for analyzing.

diff --git a/sysdeps/unix/sysv/linux/aarch64/bits/fcntl.h b/sysdeps/unix/sysv/linux/aarch64/bits/fcntl.h
index 3631903..d1010db 100644
--- a/sysdeps/unix/sysv/linux/aarch64/bits/fcntl.h
+++ b/sysdeps/unix/sysv/linux/aarch64/bits/fcntl.h
@@ -25,18 +25,29 @@
#define __O_NOFOLLOW 0100000
#define __O_DIRECT 0200000

-#define __O_LARGEFILE 0
+#ifdef __ILP32__
+# define __O_LARGEFILE 0400000
+# define __O_LARGEFILE 0

I guess this means I screwed up when I said I'd merged the kernel patch
that Yury did to fix it, sorry about that.

We need the patch to make all new architecture in the kernel default to
O_LARGEFILE, and not do this in user space. I'd suggest now to keep the
patches as part of the ILP32 series after all, to make sure they are
merged at the point when they are needed.

I am a little bit confuse about off_t. In "[PATCH 08/33] 32-bit
ABI: introduce ARCH_32BIT_OFF_T config option", it mentioned that all
the new 32bit architecture should use 64bit off_t.

Ah, so it is part of the series. I had not checked that here.

I'm preparing new submission now.
> I can join off_t, s390 and ilp32
patchsets. It seems, they will not be grabbed separately anyway, so
this may decrease confusions like this.

I am curious which one is more easily to get ack:p

Should we define off_t in aarch64(for both ilp32 and lp64) in
typesize.h as following?

diff --git a/sysdeps/unix/sysv/linux/aarch64/bits/typesizes.h b/sysdeps/unix/sysv/linux/aarch64/bits/typesizes.h
index 7073493..13b77c5 100644
--- a/sysdeps/unix/sysv/linux/aarch64/bits/typesizes.h
+++ b/sysdeps/unix/sysv/linux/aarch64/bits/typesizes.h
@@ -33,7 +33,7 @@
#define __INO64_T_TYPE __UQUAD_TYPE
#define __MODE_T_TYPE __U32_TYPE
#define __NLINK_T_TYPE __U32_TYPE
+#define __OFF_T_TYPE __SQUAD_TYPE
#define __OFF64_T_TYPE __SQUAD_TYPE
#define __PID_T_TYPE __S32_TYPE

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

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

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:



Otherwise we need to handle the pad like yury do it in
stat.h, and we need to handle the bigendian as well:

I see.

@@ -35,12 +35,21 @@ struct stat
__dev_t st_dev; /* Device. */
#ifdef __ILP32__
+#if !defined(__AARCH64EB__)
unsigned int __st_ino_pad;
# ifndef __USE_FILE_OFFSET64
__ino_t st_ino; /* File serial number. */
# else
__ino_t __st_ino; /* 32bit file serial number. */
# endif
+#if defined(__AARCH64EB__)
+ unsigned int __st_ino_pad;

This would indeed be silly, we really don't want anyone
to access the old __st_ino field or the 32-bit version of
the offset here.