linux/arch/s390
Chris Metcalf 48b25c43e6 [PATCH v3] ipc: provide generic compat versions of IPC syscalls
When using the "compat" APIs, architectures will generally want to
be able to make direct syscalls to msgsnd(), shmctl(), etc., and
in the kernel we would want them to be handled directly by
compat_sys_xxx() functions, as is true for other compat syscalls.

However, for historical reasons, several of the existing compat IPC
syscalls do not do this.  semctl() expects a pointer to the fourth
argument, instead of the fourth argument itself.  msgsnd(), msgrcv()
and shmat() expect arguments in different order.

This change adds an ARCH_WANT_OLD_COMPAT_IPC config option that can be
set to preserve this behavior for ports that use it (x86, sparc, powerpc,
s390, and mips).  No actual semantics are changed for those architectures,
and there is only a minimal amount of code refactoring in ipc/compat.c.

Newer architectures like tile (and perhaps future architectures such
as arm64 and unicore64) should not select this option, and thus can
avoid having any IPC-specific code at all in their architecture-specific
compat layer.  In the same vein, if this option is not selected, IPC_64
mode is assumed, since that's what the <asm-generic> headers expect.

The workaround code in "tile" for msgsnd() and msgrcv() is removed
with this change; it also fixes the bug that shmat() and semctl() were
not being properly handled.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-03-15 13:13:38 -04:00
..
appldata sched/accounting: Change cpustat fields to an array 2011-12-06 09:06:38 +01:00
boot [S390] Remove Kerntypes leftovers 2011-12-27 11:27:12 +01:00
crypto [S390] crypto: avoid MSA3 and MSA4 instructions in ESA mode 2011-11-14 11:19:09 +01:00
hypfs vfs: switch ->show_options() to struct dentry * 2012-01-06 23:19:54 -05:00
include/asm compat: fix compile breakage on s390 2012-02-27 07:54:27 -08:00
kernel Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2012-03-01 18:22:55 -08:00
kvm KVM: s390: announce SYNC_MMU 2011-11-17 16:25:52 +02:00
lib [S390] sparse: fix sparse warnings with __user pointers 2011-10-30 15:16:46 +01:00
math-emu s390: change to new flag variable 2011-03-17 14:02:57 +01:00
mm Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2012-03-01 18:22:55 -08:00
oprofile Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-01-06 08:02:58 -08:00
defconfig [S390] defconfig: switch on CONFIG_DEVTMPFS 2011-10-30 15:16:42 +01:00
Kbuild [S390] make arch/s390 subdirectories depend on config option 2011-12-27 11:27:12 +01:00
Kconfig [PATCH v3] ipc: provide generic compat versions of IPC syscalls 2012-03-15 13:13:38 -04:00
Kconfig.debug [S390] Write protect module text and RO data 2011-03-15 17:08:23 +01:00
Makefile [S390] cleanup entry point definition 2012-01-18 18:03:41 +01:00