- Add a mutex to protect against two processes mmapping the
  same binder_proc.
- After locking mmap_sem, check that the vma we want to access
  (still) points to the same mm_struct.
- Use proc->tsk instead of current to get the files struct since
  this is where we get the rlimit from.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
binder_update_page_range could read freed memory if the vma of the
selected process was freed right before the check that the vma
belongs to the mm struct it just locked.

If the vm_mm pointer in that freed vma struct had also been rewritten
with a value that matched the locked mm struct, then the code would
proceed and possibly modify the freed vma.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
drop part of binder memory leak "fix" as it maybe inducing reboots. Move binder source to match up (as much as possible) to current android 3.4 tegra branch from google.
fs/super.c: sync ro remount after blocking writers

Move sync_filesystem() after sb_prepare_remount_readonly().  If writers
sneak in anywhere from sync_filesystem() to sb_prepare_remount_readonly()
it can cause inodes to be dirtied and writeback to occur well after
sys_mount() has completely successfully.

This was spotted by corrupted ubifs filesystems on reboot, but appears
that it can cause issues with any filesystem using writeback.

CRs-Fixed: 627559
Change-Id: Ib417b59d39210aab2de4e5ae48b18129e8bc3e26
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
CC: Richard Weinberger <richard@nod.at>
Co-authored-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Ruder <andrew.ruder@elecsyscorp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Git-commit: 807612db2f9940b9fa6deaef054eb16d51bd3e00
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>
writeback: fix occasional slow sync(1)

In case when system contains no dirty pages, wakeup_flusher_threads() will
submit WB_SYNC_NONE writeback for 0 pages so wb_writeback() exits
immediately without doing anything, even though there are dirty inodes in
the system.  Thus sync(1) will write all the dirty inodes from a
WB_SYNC_ALL writeback pass which is slow.

Fix the problem by using get_nr_dirty_pages() in wakeup_flusher_threads()
instead of calculating number of dirty pages manually.  That function also
takes number of dirty inodes into account.

Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Paul Taysom <taysom@chromium.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: poondog <markj338@gmail.com>
bcmdhd: Reduce packet handling wakelock by half. There are a lot of android kernels out there using that too. and we can always revert if it gives trouble.
workqueues: Introduce new flag WQ_POWER_EFFICIENT for power oriented workqueues

Adapted for 3.4 from lsk-v3.10

Workqueues can be performance or power-oriented. Currently, most workqueues are
bound to the CPU they were created on. This gives good performance (due to cache
effects) at the cost of potentially waking up otherwise idle cores (Idle from
scheduler's perspective. Which may or may not be physically idle) just to
process some work. To save power, we can allow the work to be rescheduled on a
core that is already awake.

Workqueues created with the WQ_UNBOUND flag will allow some power savings.
However, we don't change the default behaviour of the system.  To enable
power-saving behaviour, a new config option CONFIG_WQ_POWER_EFFICIENT needs to
be turned on. This option can also be overridden by the
workqueue.power_efficient boot parameter.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>
workqueue: Add system wide power_efficient workqueues

Adapted for 3.4 from lsk-v3.10

This patch adds system wide workqueues aligned towards power saving. This is
done by allocating them with WQ_UNBOUND flag if 'wq_power_efficient' is set to
'true'.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>
block: queue work on power efficient wq

Adapted for 3.4 from lsk-v3.10

Block layer uses workqueues for multiple purposes. There is no real dependency
of scheduling these on the cpu which scheduled them.

On a idle system, it is observed that and idle cpu wakes up many times just to
service this work. It would be better if we can schedule it on a cpu which the
scheduler believes to be the most appropriate one.

This patch replaces normal workqueues with power efficient versions.

Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: poondog <markj338@gmail.com>
Use power efficient work queues for sound cleanup handlers.
change a few workqueues to power efficient following what was done at linux 3.17
ditto for cpcap-usb-det
ditto for usb hub and net phy
Updated defconfig to reflect +CONFIG_VFS_CACHE_PRESSURE=90 && +CONFIG_WQ_POWER_EFFICIENT_DEFAULT=y