If X32 is enabled in .config, but the binutils can't build it, issue a
warning and disable the feature rather than erroring out.

In order to support this, have CONFIG_X86_X32 be the option set in
Kconfig, and CONFIG_X86_X32_ABI be the option set by the Makefile when
it is enabled and binutils has been found to be functional.

Requested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: H. J. Lu <hjl.tools@gmail.com>
Link: http://lkml.kernel.org/r/1329696488-16970-1-git-send-email-hpa@zytor.com

Commits bb212724 and d1a797f3

 both added a call to
clear_thread_flag(TIF_X32) under set_personality_64bit() - only one is
needed.

Signed-off-by: Bobby Powers <bobbypowers@gmail.com>
Link: http://lkml.kernel.org/r/1330228774-24223-1-git-send-email-bobbypowers@gmail.com


Signed-off-by: H. Peter Anvin <hpa@zytor.com>

If a process has a non-x32 ia32 personality and changes to x32, the
process would keep its TS_COMPAT flag. x32 uses the presence of the
x32 flag on a syscall to determine compat status, so make sure
TS_COMPAT is cleared.

Signed-off-by: Bobby Powers <bobbypowers@gmail.com>
Link: http://lkml.kernel.org/r/1330230338-25077-1-git-send-email-bobbypowers@gmail.com


Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Stephen Rothwell reported that the following commit broke the
linux-next build:

  1fd36adc

: Replace the fd_sets in struct fdtable with an array of unsigned longs

Fix places where ->fds_bits needed to be removed as the core
kernel no longer uses fd_set internally for file descriptor
table management.  There are two places:

 (1) drivers/staging/android/binder.c

 (2) arch/mips/kernel/kspd.c

     Question: Should sp_cleanup() in the MIPS arch be using find_next_bit()
     or fls()?

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Ralf Bächle <ralf@linux-mips.org>
cc: Arve Hjønnevåg <arve@android.com>
Link: http://lkml.kernel.org/r/20120224105707.32170.11550.stgit@warthog.procyon.org.uk


Signed-off-by: Ingo Molnar <mingo@elte.hu>

Drop the legacy weak symbols that don't carry the __vdso prefix from
the x32 VDSO.  This is a new ABI and we don't need to support that
legacy; the actual libc will export the proper symbols.

Suggested-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/4F42E171.9080005@mit.edu


Cc: H. J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Move the prototype for x32_setup_additional_pages() to a header file,
and adjust the coding style to match standard.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: H. J. Lu <hjl.tools@gmail.com>

Add support for the x32 VDSO.  The x32 VDSO takes advantage of the
similarity between the x86-64 and the x32 ABIs to contain the same
content, only the container is different, as the x32 VDSO obviously is
an x32 shared object.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

At this point, one should be able to build an x32 kernel.

Note that for now we depend on CONFIG_IA32_EMULATION.  Long term, x32
and IA32 should be detangled.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

If CONFIG_X86_X32_ABI is defined, add the x32 system calls to the
system call tables.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Allow an x32 process to be started.

Originally-by: H. J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>

x32 uses the 64-bit signal frame format, obviously, but there are some
structures which mixes that with pointers or sizeof(long) types, as
such we have to create a handful of system calls specific to x32.  By
and large these are a mixture of the 64-bit and the compat system
calls.

Originally-by: H. J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Unfortunately a lot of the compat types are guarded with CONFIG_COMPAT
or the equivalent, so add a similar guard to <asm/sys_ia32.h> to avoid
compilation failures when CONFIG_COMPAT=n.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

x32 shares most system calls with x86-64, but unfortunately some
subsystem (the input subsystem is the chief offender) which require
is_compat() when operating with a 32-bit userspace.  The input system
actually has text files in sysfs whose meaning is dependent on
sizeof(long) in userspace!

We could solve this by having two completely disjoint system call
tables; requiring that each system call be duplicated.  This patch
takes a different approach: we add a flag to the system call number;
this flag doesn't affect the system call dispatch but requests compat
treatment from affected subsystems for the duration of the system call.

The change of cmpq to cmpl is safe since it immediately follows the
and.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Add rt_sigframe_x32 to <asm/sigframe.h>.  Unfortunately we can't just
define all the data structures unconditionally, due to the #ifdef
CONFIG_COMPAT in <linux/compat.h> and its trickle-down effects, hence
the #ifdef mess.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Add a definition for struct ucontext_x32; this is inherently a mix of
the 32- and 64-bit versions.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Export setup_sigcontext() and restore_sigcontext() from signal.c, so
we can use the 64-bit versions verbatim for x32.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

There are some definitions which are duplicated between
kernel/signal.c and ia32/ia32_signal.c; move them to a common header
file.

Rather than adding stuff to existing header files which contain data
structures, create a new header file; hence the slightly odd name
("all the good ones were taken.")

Note: nothing relied on signal_fault() being defined in
<asm/ptrace.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Generate macros for the *kernel* code to use to refer to x32 system
calls.  These have an __NR_x32_ prefix and do not include
__X32_SYSCALL_BIT.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Generate <asm/unistd_x32.h>; this exports x32 system call numbers to
user space.

[ v2: Enclose all arguments to syshdr in '' so empty arguments aren't
      dropped on the floor. ]

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Split the 64-bit system calls into "64" (64-bit only) and "common"
(64-bit or x32) and add the x32 system call numbers.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

On x86, the only difference between sys_rt_sigprocmask and
sys32_rt_sigprocmask is the alignment of the data structures.
However, x86 allows data accesses with arbitrary alignment, and
therefore there is no reason for this code to be different.

Reported-by: Gregory M. Lueck <gregory.m.lueck@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

An x32 process is *almost* the same thing as a 64-bit process with a
32-bit address limit, but there are a few minor differences -- in
particular core dumps are 32 bits and signal handling is different.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

So far this has only been used in process_64.c, but the x32 code will
need it in additional code.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

This is the same as the 64-bit posix_types.h, except that
__kernel_[u]long_t is defined to be [unsigned] long long and therefore
64 bits.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

Use explicit sizes (__u64) instead of implicit sizes (unsigned long)
in the definition for sigcontext.h; this will allow this structure to
be shared between the x86-64 native ABI and the x32 ABI.

Originally-by: H. J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/n/tip-4pr1xnnksprt7t0h3w5fw4rv@git.kernel.org

Factor out IA32 (compatibility instruction set) from 32-bit address
space in the thread_info flags; this is a precondition patch for x32
support.

Originally-by: H. J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/n/tip-4pr1xnnksprt7t0h3w5fw4rv@git.kernel.org

Wrap accesses to the fd_sets in struct fdtable (for recording open files and
close-on-exec flags) so that we can move away from using fd_sets since we
abuse the fd_set structs by not allocating the full-sized structure under
normal circumstances and by non-core code looking at the internals of the
fd_sets.

The first abuse means that use of FD_ZERO() on these fd_sets is not permitted,
since that cannot be told about their abnormal lengths.

This introduces six wrapper functions for setting, clearing and testing
close-on-exec flags and fd-is-open flags:

	void __set_close_on_exec(int fd, struct fdtable *fdt);
	void __clear_close_on_exec(int fd, struct fdtable *fdt);
	bool close_on_exec(int fd, const struct fdtable *fdt);
	void __set_open_fd(int fd, struct fdtable *fdt);
	void __clear_open_fd(int fd, struct fdtable *fdt);
	bool fd_is_open(int fd, const struct fdtable *fdt);

Note that I've prepended '__' to the names of the set/clear functions because
they require the caller to hold a lock to use them.

Note also that I haven't added wrappers for looking behind the scenes at the
the array.  Possibly that should exist too.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/20120216174942.23314.1364.stgit@warthog.procyon.org.uk


Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>

Change the xtensa architecture to use <asm-generic/posix_types.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-21-git-send-email-hpa@zytor.com
Cc: Chris Zankel <chris@zankel.net>

Change the x86 architecture to use <asm-generic/posix_types.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-20-git-send-email-hpa@zytor.com
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>

Change the sparc architecture to use <asm-generic/posix_types.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/1328677745-20121-19-git-send-email-hpa@zytor.com

Remove type overrides in <asm/posix_types.h> for the sh architecture
that are no longer necessary.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-18-git-send-email-hpa@zytor.com
Cc: Paul Mundt <lethal@linux-sh.org>

Change the s390 architecture to use <asm-generic/posix_types.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/1328677745-20121-17-git-send-email-hpa@zytor.com
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <linux390@de.ibm.com>

Change the powerpc architecture to use <asm-generic/posix_types.h>.

[ v2: fix the definition for __kernel_ssize_t ]

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-16-git-send-email-hpa@zytor.com
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>

Change the parisc architecture to use <asm-generic/posix_types.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-15-git-send-email-hpa@zytor.com
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: James Bottomley <jejb@parisc-linux.org>

Change the mn10300 architecture to use <asm-generic/posix_types.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-14-git-send-email-hpa@zytor.com
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>

Change the mips architecture to use <asm-generic/posix_types.h>.

[ v2: remove redundant definition of __kernel_loff_t ]

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-13-git-send-email-hpa@zytor.com
Cc: Ralf Baechle <ralf@linux-mips.org>

Change the m68k architecture to use <asm-generic/posix_types.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-12-git-send-email-hpa@zytor.com
Cc: Geert Uytterhoeven <geert@linux-m68k.org>

Change the m32r architecture to use <asm-generic/posix_types.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-11-git-send-email-hpa@zytor.com
Cc: Hirokazu Takata <takata@linux-m32r.org>

Change the ia64 architecture to use <asm-generic/posix_types.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-10-git-send-email-hpa@zytor.com
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>

Change the h8300 architecture to use <asm-generic/posix_types.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1328677745-20121-9-git-send-email-hpa@zytor.com
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>