This patch sets the mode field in ipc_perm as mode_t for all architectures,
as POSIX specification [1]. The changes required are as follow:
1. It moves the ipc_perm definition out of ipc.h to its own header
ipc_perm.h. It also allows consolidate the IPC_* definition on
only one header.
2. The generic implementation follow the kernel ipc64_perm size so the
syscall can be made directly without temporary buffer copy. However,
since glibc defines the MODE field as mode_t, it omits the __PAD1 field
(since glibc does not export mode_t as 16-bit for any architecture).
It is a two-fold improvement:
2.1. New implementation which follow Linux UAPI will not need to
provide an arch-specific ipc-perm.h header neither wrongly
use the wrong 16-bit definition from previous default ipc.h
(as csky did).
2.1. It allows consolidate ipc_perm definition for architectures that
already provide mode_t as 32-bit.
3. All kernel ABIs for the supported architectures already provides the
expected padding for mode type extension to 32-bit. However, some
architectures the padding has the wrong placement, so it requires
the ipc control routines (msgctl, semctl, and shmctl) to adjust the
mode field accordingly. Currently they are armeb, microblaze, m68k,
s390, and sheb.
A new assume is added, __ASSUME_SYSVIPC_BROKEN_MODE_T, which the
required ABIs define.
4. For the ABIs that define __ASSUME_SYSVIPC_BROKEN_MODE_T, it also
require compat symbols that do not adjust the mode field.
Checked on arm-linux-gnueabihf, aarch64-linux-gnu, powerpc64le-linux-gnu,
and x86_64-linux-gnu. I also checked the sysvipc tests on hppa-linux-gnu,
sh4-linux-gnu, s390x-linux-gnu, and s390-linux-gnu.
I also did a sanity test against armeb qemu usermode for the sysvipc
tests.
[BZ #18231]
* sysdeps/unix/sysv/linux/Makefile (sysdep_headers): Add
bits/ipc-perm.h.
* sysdeps/unix/sysv/linux/aarch64/bits/ipc.h: Remove file.
* sysdeps/unix/sysv/linux/alpha/bits/ipc.h: Likewise.
* sysdeps/unix/sysv/linux/hppa/bits/ipc.h: Likewise.
* sysdeps/unix/sysv/linux/ia64/bits/ipc.h: Likewise.
* sysdeps/unix/sysv/linux/mips/bits/ipc.h: Likewise.
* sysdeps/unix/sysv/linux/powerpc/bits/ipc.h: Likewise.
* sysdeps/unix/sysv/linux/s390/bits/ipc.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/bits/ipc.h: Likewise.
* sysdeps/unix/sysv/linux/arm/kernel-features.h
[__BYTE_ORDER == __BIG_ENDIAN] (__ASSUME_SYSVIPC_BROKEN_MODE_T):
Define.
* sysdeps/sysv/linux/microblaze/kernel-features.h: Likewise.
* sysdeps/unix/sysv/linux/s390/kernel-features.h
[!__s390x__] (__ASSUME_SYSVIPC_BROKEN_MODE_T): Define.
* sysdeps/unix/sysv/linux/sh/kernel-features.h
(__ASSUME_SYSVIPC_BROKEN_MODE_T): Define.
* sysdeps/unix/sysv/linux/m68k/kernel-features.h: Likewise.
* sysdeps/unix/sysv/linux/bits/ipc-perm.h: New file.
* sysdeps/unix/sysv/linux/powerpc/bits/ipc-perm.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/bits/ipc-perm.h: Likewise.
* sysdeps/unix/sysv/linux/bits/ipc.h (ipc_perm): Move to
bits/ipc-perm.h.
* sysdeps/unix/sysv/linux/hppa/bits/ipc-perm.h: New file.
* sysdeps/unix/sysv/linux/kernel-features.h: Add comment about
__ASSUME_SYSVIPC_BROKEN_MODE_T semantic.
* sysdeps/unix/sysv/linux/msgctl.c (DEFAULT_VERSION): Define as
2.31 if __ASSUME_SYSVIPC_BROKEN_MODE_T is defined.
(msgctl_syscall, __msgctl_mode16): New symbol.
(__new_msgctl): Add bits for __ASSUME_SYSVIPC_BROKEN_MODE_T.
* sysdeps/unix/sysv/linux/semctl.c: Likewise.
* sysdeps/unix/sysv/linux/shmctl.c: Likewise.
* sysdeps/unix/sysv/linux/arm/be/libc.abilist (GLIBC_2.31): Add
msgctl, semctl, and shmctl.
* sysdeps/sysv/linux/microblaze/be/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/be/libc.abilist: Likewise.
* conform/data/sys/ipc.h-data: Only xfail {struct ipc_perm} mode_t
mode for Hurd.
* sysdeps/unix/sysv/linux/m68k/Versions (libc) [GLIBC_2.31]: Add
msgctl, semctl, and shmctl.
* sysdeps/unix/sysv/linux/arm/be/Versions: New file.
* sysdeps/unix/sysv/linux/microblaze/be/Versions: Likewise.
* sysdeps/unix/sysv/linux/sh/be/Versions: Likewise.
[1] http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_ipc.h.html