Commit graph

17 commits

Author SHA1 Message Date
Linus Torvalds
13da9e200f Revert "endian: #define __BYTE_ORDER"
This reverts commit b3b77c8cae, which was
also totally broken (see commit 0d2daf5cc8 that reverted the crc32
version of it).  As reported by Stephen Rothwell, it causes problems on
big-endian machines:

> In file included from fs/jfs/jfs_types.h:33,
>                  from fs/jfs/jfs_incore.h:26,
>                  from fs/jfs/file.c:22:
> fs/jfs/endian24.h:36:101: warning: "__LITTLE_ENDIAN" is not defined

The kernel has never had that crazy "__BYTE_ORDER == __LITTLE_ENDIAN"
model.  It's not how we do things, and it isn't how we _should_ do
things.  So don't go there.

Requested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-26 08:30:15 -07:00
Joakim Tjernlund
b3b77c8cae endian: #define __BYTE_ORDER
Linux does not define __BYTE_ORDER in its endian header files which makes
some header files bend backwards to get at the current endian.  Lets
#define __BYTE_ORDER in big_endian.h/litte_endian.h to make it easier for
header files that are used in user space too.

In userspace the convention is that

  1. _both_ __LITTLE_ENDIAN and __BIG_ENDIAN are defined,
  2. you have to test for e.g. __BYTE_ORDER == __BIG_ENDIAN.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:02 -07:00
Harvey Harrison
991c0e6d1a byteorder: only use linux/swab.h
The first step to make swab.h a regular header that will
include an asm/swab.h with arch overrides.

Avoid the gratuitous differences introduced in the new
linux/swab.h by naming the ___constant_swabXX bits and
__fswabXX bits exactly as found in the old implementation
in byteorder/swab[b].h

Use this new swab.h in byteorder/[big|little]_endian.h and
remove the two old swab headers.

Although the inclusion of asm/byteorder.h looks strange in
linux/swab.h, this will allow each arch to move the actual
arch overrides for the swab bits in an asm file and then
the includes can be cleaned up without requiring a flag day
for all arches at once.

Keep providing __fswabXX in case some userspace was using them
directly, but the revised __swabXX should be used instead in
any new code and will always do constant folding not dependent
on the optimization level, which means the __constant versions
can be phased out in-kernel.

Arches that use the old-style arch macros will lose their
optimized versions until they move to the new style, but at
least they will still compile.  Many arches have already moved
and the patches to move the remaining arches are trivial.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 18:10:26 -08:00
Harvey Harrison
1d8cca44b6 byteorder: provide swabb.h generically in asm/byteorder.h
This is needed during the transition to the new byteorder headers as the
swabb.h functionality will be provided from asm/byteorder.h in the new
version.  To avoid breakage on arches still using the old implementation,
provide swabb.h from asm/byteorder.h as well.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:40 -07:00
David Miller
3d6f4a20cc endian: Always evaluate arguments.
Changeset 7fa897b91a ("ide: trivial sparse
annotations") created an IDE bootup regression on big-endian systems.

In drivers/ide/ide-iops.c, function ide_fixstring() we now have the
loop:

		for (p = end ; p != s;)
			be16_to_cpus((u16 *)(p -= 2));

which will never terminate on big-endian because in such
a configuration be16_to_cpus() evaluates to "do { } while (0)"

Therefore, always evaluate the arguments to nop endian transformation
operations.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 09:28:09 -07:00
Robert P. J. Day
969a19f1c4 Drop the exporting of empty <linux/byteorder/generic.h>
Fix up the contents of <linux/byteorder/> so that it doesn't export a
content-free generic.h to user space.  This involves:

* Removing the __KERNEL__ tests from generic.h and dropping it from
  Kbuild.
* Wrapping the inclusions of generic.h in both big_endian.h and
  little_endian.h in __KERNEL__ tests.
* Shifting big_endian.h and little_endian.h from header-y to
  unifdef-y in Kbuild.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:54 -07:00
Marcin Slusarz
8b5f688368 byteorder: move le32_add_cpu & friends from OCFS2 to core
This patchset moves le*_add_cpu and be*_add_cpu functions from OCFS2 to core
header (1st), converts ext3 filesystem to this API (2nd) and replaces XFS
different named functions with new ones (3rd).

There are many places where these functions will be useful.  Just look at:
grep -r 'cpu_to_[ble12346]*([ble12346]*_to_cpu.*[-+]' linux-src/ Patch for
ext3 is an example how conversions will probably look like.

This patch:

- move inline functions which add native byte order variable to
  little/big endian variable to core header
  * le16_add_cpu(__le16 *var, u16 val)
  * le32_add_cpu(__le32 *var, u32 val)
  * le64_add_cpu(__le64 *var, u64 val)
  * be32_add_cpu(__be32 *var, u32 val)
- add for completeness:
  * be16_add_cpu(__be16 *var, u16 val)
  * be64_add_cpu(__be64 *var, u64 val)

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Acked-by: Mark Fasheh <mark.fasheh@oracle.com>
Cc: David Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:32 -08:00
Michal Schmidt
ee7b9e3706 Fix compilation of drivers with -O0
It is sometimes useful to compile individual drivers with optimization
disabled for easier debugging.  Currently drivers which use htonl() and
similar functions don't compile with -O0.  This patch fixes it.  It also
removes obsolete and misleading comments.  This header is not for
userspace, so we don't have to care about strange programs these comments
mention.

(akpm: -O0 probably isn't a good idea, but this code looks pretty crufty and
unuseful)

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:00 -07:00
Trent Piepho
8e2c20023f Fix constant folding and poor optimization in byte swapping code
Constant folding does not work for the swabXX() byte swapping functions,
and the C versions optimize poorly.

Attempting to initialize a global variable to swab16(0x1234) or put
something like "case swab32(42):" in a switch statement will not compile.
It can work, swab.h just isn't doing it correctly.  This patch fixes that.

Contrary to the comment in asm-i386/byteorder.h, gcc does not recognize the
"C" version of swab16 and turn it into efficient code.  gcc can do this,
just not with the current code.  The simple function:

u16 foo(u16 x) { return swab16(x); }

Would compile to:
        movzwl  %ax, %eax
        movl    %eax, %edx
        shrl    $8, %eax
        sall    $8, %edx
        orl     %eax, %edx

With this patch, it will compile to:
        rolw    $8, %ax

I also attempted to document the maze different macros/inline functions
that are used to create the final product.

Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Cc: Francois-Rene Rideau <fare@tunes.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:14:59 -07:00
Adrian Bunk
bfb58478fe [PATCH] cleanup linux/byteorder/swabb.h
- no longer a userspace header
- add #include <linux/types.h> for in-kernel compilation

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:34 -08:00
Adrian Bunk
7131b6d167 [PATCH] remove include/linux/byteorder/pdp_endian.h
include/linux/byteorder/pdp_endian.h is completely unused, and the comment in
the file itself states that it's both untested and only a proof-of-concept.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:24 -08:00
David Woodhouse
fadcfa33b6 [HEADERS] One line per header in Kbuild files to reduce conflicts
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-09-19 12:43:58 +01:00
David Woodhouse
8555255f0b Add generic Kbuild files for 'make headers_install'
This adds the Kbuild files listing the files which are to be installed by
the 'headers_install' make target, in generic directories.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-06-18 12:14:01 +01:00
Andrew Morton
a136564702 [PATCH] remove gcc-2 checks
Remove various things which were checking for gcc-1.x and gcc-2.x compilers.

From: Adrian Bunk <bunk@stusta.de>

    Some documentation updates and removes some code paths for gcc < 3.2.

Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:14:02 -08:00
Ed L. Cashin
e0487992ce [BYTEORDER]: Document alignment and byteorder macros
This patch comments the fact that although passing le64_to_cpup et
al. is within the intended use of the byteorder macros, using
get_unaligned is the recommended way to go.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-19 19:57:36 -07:00
Andrew Morton
05133fc498 [PATCH] swabb.h warning fixes
In file included from drivers/media/dvb/ttpci/av7110_hw.c:38:
include/linux/byteorder/swabb.h:96: warning: type qualifiers ignored on function return type
include/linux/byteorder/swabb.h:110: warning: type qualifiers ignored on function return type
In file included from drivers/media/dvb/ttpci/av7110_v4l.c:36:
include/linux/byteorder/swabb.h:96: warning: type qualifiers ignored on function return type
include/linux/byteorder/swabb.h:110: warning: type qualifiers ignored on function return type
In file included from drivers/media/dvb/ttpci/av7110_av.c:37:
include/linux/byteorder/swabb.h:96: warning: type qualifiers ignored on function return type
include/linux/byteorder/swabb.h:110: warning: type qualifiers ignored on function return type
drivers/isdn/icn/icn.c:719:4: warning: #warning TODO test headroom or use skb->nb to flag ACK
In file included from drivers/media/dvb/ttpci/av7110_ca.c:39:
include/linux/byteorder/swabb.h:96: warning: type qualifiers ignored on function return type
include/linux/byteorder/swabb.h:110: warning: type qualifiers ignored on function return type
In file included from drivers/media/dvb/ttpci/av7110.c:41:
include/linux/byteorder/swabb.h:96: warning: type qualifiers ignored on function return type
include/linux/byteorder/swabb.h:110: warning: type qualifiers ignored on function return type

Does declaring a function to return a const value actually mean something to
gcc?

Dunno.  Kill it and replace sone `__inline__'s with `inline' too.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 21:20:31 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00