Fix kernel compression support
decompressors: add XZ decompressor module

In userspace, the .lzma format has become mostly a legacy file format that
got superseded by the .xz format.  Similarly, LZMA Utils was superseded by
XZ Utils.

These patches add support for XZ decompression into the kernel.  Most of
the code is as is from XZ Embedded <http://tukaani.org/xz/embedded.html>.
It was written for the Linux kernel but is usable in other projects too.

Advantages of XZ over the current LZMA code in the kernel:
  - Nice API that can be used by other kernel modules; it's
    not limited to kernel, initramfs, and initrd decompression.
  - Integrity check support (CRC32)
  - BCJ filters improve compression of executable code on
    certain architectures. These together with LZMA2 can
    produce a few percent smaller kernel or Squashfs images
    than plain LZMA without making the decompression slower.

This patch: Add the main decompression code (xz_dec), testing module
(xz_dec_test), wrapper script (xz_wrap.sh) for the xz command line tool,
and documentation.  The xz_dec module is enough to have a usable XZ
decompressor e.g.  for Squashfs.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
decompressors: add boot-time XZ support

This implements the API defined in <linux/decompress/generic.h> which is
used for kernel, initramfs, and initrd decompression.  This patch together
with the first patch is enough for XZ-compressed initramfs and initrd;
XZ-compressed kernel will need arch-specific changes.

The buffering requirements described in decompress_unxz.c are stricter
than with gzip, so the relevant changes should be done to the
arch-specific code when adding support for XZ-compressed kernel.
Similarly, the heap size in arch-specific pre-boot code may need to be
increased (30 KiB is enough).

The XZ decompressor needs memmove(), memeq() (memcmp() == 0), and
memzero() (memset(ptr, 0, size)), which aren't available in all
arch-specific pre-boot environments.  I'm including simple versions in
decompress_unxz.c, but a cleaner solution would naturally be nicer.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
XZ decompressor: Fix decoding of empty LZMA2 streams

The old code considered valid empty LZMA2 streams to be corrupt.
Note that a typical empty .xz file has no LZMA2 data at all,
and thus most .xz files having no uncompressed data are handled
correctly even without this fix.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ARM: support XZ compressed kernels

Wire up support for the XZ decompressor

Signed-off-by: Imre Kaloz <kaloz at openwrt.org>
XZ: Fix missing <linux/kernel.h> include

<linux/kernel.h> is needed for min_t. The old version
happened to work on x86 because <asm/unaligned.h>
indirectly includes <linux/kernel.h>, but it didn't
work on ARM.

<linux/kernel.h> includes <asm/byteorder.h> so it's
not necessary to include it explicitly anymore.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
XZ: Fix incorrect XZ_BUF_ERROR

xz_dec_run() could incorrectly return XZ_BUF_ERROR if all of the
following was true:

 - The caller knows how many bytes of output to expect and only provides
   that much output space.

 - When the last output bytes are decoded, the caller-provided input
   buffer ends right before the LZMA2 end of payload marker.  So LZMA2
   won't provide more output anymore, but it won't know it yet and thus
   won't return XZ_STREAM_END yet.

 - A BCJ filter is in use and it hasn't left any unfiltered bytes in the
   temp buffer.  This can happen with any BCJ filter, but in practice
   it's more likely with filters other than the x86 BCJ.

This fixes <https://bugzilla.redhat.com/show_bug.cgi?id=735408> where
Squashfs thinks that a valid file system is corrupt.

This also fixes a similar bug in single-call mode where the uncompressed
size of a block using BCJ + LZMA2 was 0 bytes and caller provided no
output space.  Many empty .xz files don't contain any blocks and thus
don't trigger this bug.

This also tweaks a closely related detail: xz_dec_bcj_run() could call
xz_dec_lzma2_run() to decode into temp buffer when it was known to be
useless.  This was harmless although it wasted a minuscule number of CPU
cycles.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Update Default Config
scripts:conf.c Fix warning: variable 'type' set but not used

Not sure if this is correct or not, but with
make menuconfig
  HOSTCC  scripts/kconfig/conf.o
scripts/kconfig/conf.c: In function 'conf_sym':
scripts/kconfig/conf.c:159:6: warning: variable 'type' set but not used
scripts/kconfig/conf.c: In function 'conf_choice':
scripts/kconfig/conf.c:231:6: warning: variable 'type' set but not used
  HOSTLD  scripts/kconfig/mconf

I get this using gcc 4.6.0 the below change fixes this form me.

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
md: dm-crypt: Add option to re-use a new global work-queue.

Typically, dm-crypt instances each have their own set of kcrypt/kcrypt_io
work-queues. This patch adds an option which will create one set of
work-queues on init, and re-uses them for all dm-crypt target instances
in order to cut down on resource overhead on embedded systems.

NOTE: If you use stacked dm-crypt instances, then enabling this option
may cause a deadlock.

Cc: Milan Broz <mbroz@redhat.com>
Cc: Brian Swetland <swetland@google.com>
Cc: Andrew Morton <apkm@linux-foundation.org>
Cc: Christophe Saout <christophe@saout.de>
Signed-off-by: San Mehat <san@google.com>
input: evdev: Add missing wake_lock_destroy

Change-Id: Ief1ef44d98a197e5b457f5e8617c413e76e3c6d2
Signed-off-by: Benoit Goby <benoit@android.com>
staging: binder: Fix use of uninitialized variable.

Under an extremely rare condition, the variable return_error may
not be set.  This patch initializes the value to a known "bad"
value, and checks before return to ensure return_error has been
set.

Signed-off-by: Nick Kralevich <nnk@google.com>
msm: Quiet remap message

Make the arch_ioremap message a pr_debug as it isn't very
useful normally.

Change-Id: I2a6198024f6692c0e4648445d0ab6428e3952028
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
proc: make /proc/pid/limits world readable

Having the limits file world readable will ease the task of system
management on systems where root privileges might be restricted.

Having admin restricted with root priviledges, he/she could not check
other users process' limits.

Also it'd align with most of the /proc stat files.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Eugene Teo <eugene@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm: ashmem: Add cache clean and invalidate ioctls for ashmem

Change-Id: Idc120f9f869c1a68e5f012327aa7f599ac065fce
CRs-fixed: 291124
Signed-off-by: Shubhraprakash Das <sadas@codeaurora.org>
Kbuild: Export ashmem header file to user space

Change-Id: I60c49b3b85b88e98843c27160dbf1c9bc5032302
CRs-fixed: 291124
Signed-off-by: Shubhraprakash Das <sadas@codeaurora.org>
Fix spelling mistake in jhash

Fix a spelling mistake.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
ipv6: Prepare the tree for un-inlined jhash.

jhash is widely used in the kernel and because the functions
are inlined, the cost in size is significant. Also, the new jhash
functions are slightly larger than the previous ones so better un-inline.
As a preparation step, the calls to the internal macros are replaced
with the plain jhash function calls.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: David S. Miller <davem@davemloft.net>
The new jhash implementation

The current jhash.h implements the lookup2() hash function by Bob Jenkins.
However, lookup2() is outdated as Bob wrote a new hash function called
lookup3(). The patch replaces the lookup2() implementation of the 'jhash*'
functions with that of lookup3().

You can read a longer comparison of the two and other hash functions at
http://burtleburtle.net/bob/hash/doobs.html.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
cgroups: export cgroup_iter_{start,next,end}

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>