Most LM75-compatible chips can either sample much faster or with a
much better resolution than the original LM75 chip. So far the lm75
driver did not let the user take benefit of these improvements. Do it
now.

I decided to almost always configure the chip to use the best
resolution possible, which also means the longest sample time. The
only chips for which I didn't are the DS75, DS1775 and STDS75, because
they are really too slow in 12-bit mode (1.2 to 1.5 second worst case)
so I went for 11-bit mode as a more reasonable tradeoff. This choice is
dictated by the fact that the hwmon subsystem is meant for system
monitoring, it has never been supposed to be ultra-fast, and as a
matter of fact we do cache the sampled values in almost all drivers.

If anyone isn't pleased with these default settings, they can always
introduce a platform data structure or DT support for the lm75. That
being said, it seems nobody ever complained that the driver wouldn't
refresh the value faster than every 1.5 second, and the change made
it faster for all chips even in 12-bit mode, so I don't expect any
complaint.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NGuenter Roeck <linux@roeck-us.net>

For debugging purposes, it is useful to have a name-string added
while exporting buffers. Hence, dma_buf_export() is replaced with
dma_buf_export_named(), which additionally takes 'exp_name' as a
parameter.

For backward compatibility, and for lazy exporters who don't wish to
name themselves, a #define dma_buf_export() is also made available,
which adds a __FILE__ instead of 'exp_name'.

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
  [Thanks for the idea!]
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NSumit Semwal <sumit.semwal@linaro.org>

Currently help message of /proc/sysrq-trigger highlight its
upper-case characters, like below:

      SysRq : HELP : loglevel(0-9) reBoot Crash terminate-all-tasks(E)
      memory-full-oom-kill(F) kill-all-tasks(I) ...

this would confuse user trigger sysrq by upper-case character, which is
inconsistent with the real lower-case character registed key.

This inconsistent help message will also lead more confused when
26 upper-case letters put into use in future.

This patch fix sysrq documentation.
Signed-off-by: Nzhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

print_symbol takes a long and converts it to a function
name and offset.  %pS does something similar, but doesn't
translate the address via __builtin_extract_return_addr.
%pSR does the translation.

This will enable replacing multiple calls like
	printk(...);
	printk_symbol(addr);
	printk("\n");
with a single non-interleavable in dmesg
	printk("... %pSR\n", (void *)addr);

Update documentation too.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Add descriptions about 'stale_rw' and 'nostale_ro' nfs options in
filesystem/vfat.txt
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NRavishankar N <ravi.n1@samsung.com>
Signed-off-by: NAmit Sahrawat <a.sahrawat@samsung.com>
Acked-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Acked-by: NRob Landley <rob@landley.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJoachim Eastwood <manabian@gmail.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As people started using Suggested-by as standard signature, adding
"Suggested-by" to the standard signature so that checkpatch won't
generate warning when Suggested-by is used in patch signature
Signed-off-by: NMugunthan V N <mugunthanvnm@ti.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NMatus Ujhelyi <matus.ujhelyi@streamunlimited.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NMatus Ujhelyi <matus.ujhelyi@streamunlimited.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Enable supporting the DT structure of LP855x family devices.  If the
platform data is NULL, the driver tries to parse a DT structure.  Then,
the platform data is copied from the DT.  Documentation is added as well.
Signed-off-by: NMilo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The 'load_new_rom_data' was used for checking whether new ROM data should
be updated or not.

However, we can decide it with 'size_program' data.  If the size is
greater than 0, it means updating ROM area is required.  Otherwise, the
default ROM data will be used.  Therefore, this duplicate platform data
can be removed.
Signed-off-by: NMilo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The brightness of LP855x devices is controlled by I2C register or PWM
input .  This mode was selected through the platform data, but it can be
chosen by the driver internally without platform data configuration.

How to decide the control mode:
  If the PWM period has specific value, the mode is PWM input.
  On the other hand, the mode is register-based.
  This mode selection is done on the _probe().

Move 'mode' from a header file to the driver private data structure,
'lp855 x'.  And correlated code was replaced.
Signed-off-by: NMilo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch depends on "genalloc: add devres support, allow to find a
managed pool by device", which provides the of_get_named_gen_pool and
dev_get_gen_pool functions.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Acked-by: NJavier Martin <javier.martin@vista-silicon.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Dong Aisheng <dong.aisheng@linaro.org>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Huang Shijie <shijie8@gmail.com>
Cc: Matt Porter <mporter@ti.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This driver requests and remaps a memory region as configured in the
device tree.  It serves memory from this region via the genalloc API.  It
optionally enables the SRAM clock.

Other drivers can retrieve the genalloc pool from a phandle pointing to
this drivers' device node in the device tree.

The allocation granularity is hard-coded to 32 bytes for now, to make the
SRAM driver useful for the 6502 remoteproc driver.  There is overhead for
bigger SRAMs, where only a much coarser allocation granularity is needed:
At 32 bytes minimum allocation size, a 256 KiB SRAM needs a 1 KiB bitmap
to track allocations.

[akpm@linux-foundation.org: fix Kconfig text, make sram_init static]
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Tested-by: NMichal Simek <monstr@monstr.eu>
Cc: Dong Aisheng <dong.aisheng@linaro.org>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Huang Shijie <shijie8@gmail.com>
Cc: Javier Martin <javier.martin@vista-silicon.com>
Cc: Matt Porter <mporter@ti.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With this patch userland applications that want to maintain the
interactivity/memory allocation cost can use the pressure level
notifications.  The levels are defined like this:

The "low" level means that the system is reclaiming memory for new
allocations.  Monitoring this reclaiming activity might be useful for
maintaining cache level.  Upon notification, the program (typically
"Activity Manager") might analyze vmstat and act in advance (i.e.
prematurely shutdown unimportant services).

The "medium" level means that the system is experiencing medium memory
pressure, the system might be making swap, paging out active file
caches, etc.  Upon this event applications may decide to further analyze
vmstat/zoneinfo/memcg or internal memory usage statistics and free any
resources that can be easily reconstructed or re-read from a disk.

The "critical" level means that the system is actively thrashing, it is
about to out of memory (OOM) or even the in-kernel OOM killer is on its
way to trigger.  Applications should do whatever they can to help the
system.  It might be too late to consult with vmstat or any other
statistics, so it's advisable to take an immediate action.

The events are propagated upward until the event is handled, i.e.  the
events are not pass-through.  Here is what this means: for example you
have three cgroups: A->B->C.  Now you set up an event listener on
cgroups A, B and C, and suppose group C experiences some pressure.  In
this situation, only group C will receive the notification, i.e.  groups
A and B will not receive it.  This is done to avoid excessive
"broadcasting" of messages, which disturbs the system and which is
especially bad if we are low on memory or thrashing.  So, organize the
cgroups wisely, or propagate the events manually (or, ask us to
implement the pass-through events, explaining why would you need them.)

Performance wise, the memory pressure notifications feature itself is
lightweight and does not require much of bookkeeping, in contrast to the
rest of memcg features.  Unfortunately, as of current memcg
implementation, pages accounting is an inseparable part and cannot be
turned off.  The good news is that there are some efforts[1] to improve
the situation; plus, implementing the same, fully API-compatible[2]
interface for CONFIG_MEMCG=n case (e.g.  embedded) is also a viable
option, so it will not require any changes on the userland side.

[1] http://permalink.gmane.org/gmane.linux.kernel.cgroups/6291
[2] http://lkml.org/lkml/2013/2/21/454

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix CONFIG_CGROPUPS=n warnings]
Signed-off-by: NAnton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: NKirill A. Shutemov <kirill@shutemov.name>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Leonid Moiseichuk <leonid.moiseichuk@nokia.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add an admin_reserve_kbytes knob to allow admins to change the hardcoded
memory reserve to something other than 3%, which may be multiple
gigabytes on large memory systems.  Only about 8MB is necessary to
enable recovery in the default mode, and only a few hundred MB are
required even when overcommit is disabled.

This affects OVERCOMMIT_GUESS and OVERCOMMIT_NEVER.

admin_reserve_kbytes is initialized to min(3% free pages, 8MB)

I arrived at 8MB by summing the RSS of sshd or login, bash, and top.

Please see first patch in this series for full background, motivation,
testing, and full changelog.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: make init_admin_reserve() static]
Signed-off-by: NAndrew Shewmaker <agshew@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add user_reserve_kbytes knob.

Limit the growth of the memory reserved for other user processes to
min(3% current process size, user_reserve_pages).  Only about 8MB is
necessary to enable recovery in the default mode, and only a few hundred
MB are required even when overcommit is disabled.

user_reserve_pages defaults to min(3% free pages, 128MB)

I arrived at 128MB by taking the max VSZ of sshd, login, bash, and top ...
then adding the RSS of each.

This only affects OVERCOMMIT_NEVER mode.

Background

1. user reserve

__vm_enough_memory reserves a hardcoded 3% of the current process size for
other applications when overcommit is disabled.  This was done so that a
user could recover if they launched a memory hogging process.  Without the
reserve, a user would easily run into a message such as:

bash: fork: Cannot allocate memory

2. admin reserve

Additionally, a hardcoded 3% of free memory is reserved for root in both
overcommit 'guess' and 'never' modes.  This was intended to prevent a
scenario where root-cant-log-in and perform recovery operations.

Note that this reserve shrinks, and doesn't guarantee a useful reserve.

Motivation

The two hardcoded memory reserves should be updated to account for current
memory sizes.

Also, the admin reserve would be more useful if it didn't shrink too much.

When the current code was originally written, 1GB was considered
"enterprise".  Now the 3% reserve can grow to multiple GB on large memory
systems, and it only needs to be a few hundred MB at most to enable a user
or admin to recover a system with an unwanted memory hogging process.

I've found that reducing these reserves is especially beneficial for a
specific type of application load:

 * single application system
 * one or few processes (e.g. one per core)
 * allocating all available memory
 * not initializing every page immediately
 * long running

I've run scientific clusters with this sort of load.  A long running job
sometimes failed many hours (weeks of CPU time) into a calculation.  They
weren't initializing all of their memory immediately, and they weren't
using calloc, so I put systems into overcommit 'never' mode.  These
clusters run diskless and have no swap.

However, with the current reserves, a user wishing to allocate as much
memory as possible to one process may be prevented from using, for
example, almost 2GB out of 32GB.

The effect is less, but still significant when a user starts a job with
one process per core.  I have repeatedly seen a set of processes
requesting the same amount of memory fail because one of them could not
allocate the amount of memory a user would expect to be able to allocate.
For example, Message Passing Interfce (MPI) processes, one per core.  And
it is similar for other parallel programming frameworks.

Changing this reserve code will make the overcommit never mode more useful
by allowing applications to allocate nearly all of the available memory.

Also, the new admin_reserve_kbytes will be safer than the current behavior
since the hardcoded 3% of available memory reserve can shrink to something
useless in the case where applications have grabbed all available memory.

Risks

* "bash: fork: Cannot allocate memory"

  The downside of the first patch-- which creates a tunable user reserve
  that is only used in overcommit 'never' mode--is that an admin can set
  it so low that a user may not be able to kill their process, even if
  they already have a shell prompt.

  Of course, a user can get in the same predicament with the current 3%
  reserve--they just have to launch processes until 3% becomes negligible.

* root-cant-log-in problem

  The second patch, adding the tunable rootuser_reserve_pages, allows
  the admin to shoot themselves in the foot by setting it too small.  They
  can easily get the system into a state where root-can't-log-in.

  However, the new admin_reserve_kbytes will be safer than the current
  behavior since the hardcoded 3% of available memory reserve can shrink
  to something useless in the case where applications have grabbed all
  available memory.

Alternatives

 * Memory cgroups provide a more flexible way to limit application memory.

   Not everyone wants to set up cgroups or deal with their overhead.

 * We could create a fourth overcommit mode which provides smaller reserves.

   The size of useful reserves may be drastically different depending
   on the whether the system is embedded or enterprise.

 * Force users to initialize all of their memory or use calloc.

   Some users don't want/expect the system to overcommit when they malloc.
   Overcommit 'never' mode is for this scenario, and it should work well.

The new user and admin reserve tunables are simple to use, with low
overhead compared to cgroups.  The patches preserve current behavior where
3% of memory is less than 128MB, except that the admin reserve doesn't
shrink to an unusable size under pressure.  The code allows admins to tune
for embedded and enterprise usage.

FAQ

 * How is the root-cant-login problem addressed?
   What happens if admin_reserve_pages is set to 0?

   Root is free to shoot themselves in the foot by setting
   admin_reserve_kbytes too low.

   On x86_64, the minimum useful reserve is:
     8MB for overcommit 'guess'
   128MB for overcommit 'never'

   admin_reserve_pages defaults to min(3% free memory, 8MB)

   So, anyone switching to 'never' mode needs to adjust
   admin_reserve_pages.

 * How do you calculate a minimum useful reserve?

   A user or the admin needs enough memory to login and perform
   recovery operations, which includes, at a minimum:

   sshd or login + bash (or some other shell) + top (or ps, kill, etc.)

   For overcommit 'guess', we can sum resident set sizes (RSS)
   because we only need enough memory to handle what the recovery
   programs will typically use. On x86_64 this is about 8MB.

   For overcommit 'never', we can take the max of their virtual sizes (VSZ)
   and add the sum of their RSS. We use VSZ instead of RSS because mode
   forces us to ensure we can fulfill all of the requested memory allocations--
   even if the programs only use a fraction of what they ask for.
   On x86_64 this is about 128MB.

   When swap is enabled, reserves are useful even when they are as
   small as 10MB, regardless of overcommit mode.

   When both swap and overcommit are disabled, then the admin should
   tune the reserves higher to be absolutley safe. Over 230MB each
   was safest in my testing.

 * What happens if user_reserve_pages is set to 0?

   Note, this only affects overcomitt 'never' mode.

   Then a user will be able to allocate all available memory minus
   admin_reserve_kbytes.

   However, they will easily see a message such as:

   "bash: fork: Cannot allocate memory"

   And they won't be able to recover/kill their application.
   The admin should be able to recover the system if
   admin_reserve_kbytes is set appropriately.

 * What's the difference between overcommit 'guess' and 'never'?

   "Guess" allows an allocation if there are enough free + reclaimable
   pages. It has a hardcoded 3% of free pages reserved for root.

   "Never" allows an allocation if there is enough swap + a configurable
   percentage (default is 50) of physical RAM. It has a hardcoded 3% of
   free pages reserved for root, like "Guess" mode. It also has a
   hardcoded 3% of the current process size reserved for additional
   applications.

 * Why is overcommit 'guess' not suitable even when an app eventually
   writes to every page? It takes free pages, file pages, available
   swap pages, reclaimable slab pages into consideration. In other words,
   these are all pages available, then why isn't overcommit suitable?

   Because it only looks at the present state of the system. It
   does not take into account the memory that other applications have
   malloced, but haven't initialized yet. It overcommits the system.

Test Summary

There was little change in behavior in the default overcommit 'guess'
mode with swap enabled before and after the patch. This was expected.

Systems run most predictably (i.e. no oom kills) in overcommit 'never'
mode with swap enabled. This also allowed the most memory to be allocated
to a user application.

Overcommit 'guess' mode without swap is a bad idea. It is easy to
crash the system. None of the other tested combinations crashed.
This matches my experience on the Roadrunner supercomputer.

Without the tunable user reserve, a system in overcommit 'never' mode
and without swap does not allow the admin to recover, although the
admin can.

With the new tunable reserves, a system in overcommit 'never' mode
and without swap can be configured to:

1. maximize user-allocatable memory, running close to the edge of
recoverability

2. maximize recoverability, sacrificing allocatable memory to
ensure that a user cannot take down a system

Test Description

Fedora 18 VM - 4 x86_64 cores, 5725MB RAM, 4GB Swap

System is booted into multiuser console mode, with unnecessary services
turned off. Caches were dropped before each test.

Hogs are user memtester processes that attempt to allocate all free memory
as reported by /proc/meminfo

In overcommit 'never' mode, memory_ratio=100

Test Results

3.9.0-rc1-mm1

Overcommit | Swap | Hogs | MB Got/Wanted | OOMs | User Recovery | Admin Recovery
----------   ----   ----   -------------   ----   -------------   --------------
guess        yes    1      5432/5432       no     yes             yes
guess        yes    4      5444/5444       1      yes             yes
guess        no     1      5302/5449       no     yes             yes
guess        no     4      -               crash  no              no

never        yes    1      5460/5460       1      yes             yes
never        yes    4      5460/5460       1      yes             yes
never        no     1      5218/5432       no     no              yes
never        no     4      5203/5448       no     no              yes

3.9.0-rc1-mm1-tunablereserves

User and Admin Recovery show their respective reserves, if applicable.

Overcommit | Swap | Hogs | MB Got/Wanted | OOMs | User Recovery | Admin Recovery
----------   ----   ----   -------------   ----   -------------   --------------
guess        yes    1      5419/5419       no     - yes           8MB yes
guess        yes    4      5436/5436       1      - yes           8MB yes
guess        no     1      5440/5440       *      - yes           8MB yes
guess        no     4      -               crash  - no            8MB no

* process would successfully mlock, then the oom killer would pick it

never        yes    1      5446/5446       no     10MB yes        20MB yes
never        yes    4      5456/5456       no     10MB yes        20MB yes
never        no     1      5387/5429       no     128MB no        8MB barely
never        no     1      5323/5428       no     226MB barely    8MB barely
never        no     1      5323/5428       no     226MB barely    8MB barely

never        no     1      5359/5448       no     10MB no         10MB barely

never        no     1      5323/5428       no     0MB no          10MB barely
never        no     1      5332/5428       no     0MB no          50MB yes
never        no     1      5293/5429       no     0MB no          90MB yes

never        no     1      5001/5427       no     230MB yes       338MB yes
never        no     4*     4998/5424       no     230MB yes       338MB yes

* more memtesters were launched, able to allocate approximately another 100MB

Future Work

 - Test larger memory systems.

 - Test an embedded image.

 - Test other architectures.

 - Time malloc microbenchmarks.

 - Would it be useful to be able to set overcommit policy for
   each memory cgroup?

 - Some lines are slightly above 80 chars.
   Perhaps define a macro to convert between pages and kb?
   Other places in the kernel do this.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: make init_user_reserve() static]
Signed-off-by: NAndrew Shewmaker <agshew@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

iostats.txt has a merged description of fields 2 and 6, but it's not obvious.
This patch adds a field 6, pointing to the merged description of field 6 in
field 2.
Signed-off-by: NDavid Hilton <david.hilton.p@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This is primarily useful when there's a driver that doesn't claim clocks
properly, but the bootloader leaves them on. It's not expected to be used
in normal cases, but for bringup and debug it's very useful to have the
option to not gate unclaimed clocks that are still on.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NMike Turquette <mturquette@linaro.org>
[mturquette@linaro.org: fixed up trivial merge issue]

Patch adds device tree probe support for mc13783-regulator driver.
Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Signed-off-by: NMark Brown <broonie@sirena.org.uk>

Add some documentation about the self describing metadata and the
code templates used to implement it.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

The main advantge of this new upcall mechanism is that it can handle
big tickets as seen in Kerberos implementations where tickets carry
authorization data like the MS-PAC buffer with AD or the Posix Authorization
Data being discussed in IETF on the krbwg working group.

The Gssproxy program is used to perform the accept_sec_context call on the
kernel's behalf. The code is changed to also pass the input buffer straight
to upcall mechanism to avoid allocating and copying many pages as tokens can
be as big (potentially more in future) as 64KiB.
Signed-off-by: NSimo Sorce <simo@redhat.com>
[bfields: containerization, negotiation api]
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This patch allows timeriomem_rng to be used via devicetree.
Signed-off-by: NAlexander Clouter <alex@digriz.org.uk>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This adds a driver for random number generator present on Broadcom BCM2835 SoC,
used in Raspberry Pi and Roku 2 devices.
Signed-off-by: NDom Cobley <popcornmix@gmail.com>
Signed-off-by: NLubomir Rintel <lkundrak@v3.sk>
Tested-by: NStephen Warren <swarren@wwwdotorg.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Matt Mackall <mpm@selenic.com>
Cc: linux-rpi-kernel@lists.infradead.org
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Bring the timestamping section in sync with the implementation.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a simple low-level voting mutex implementation
to be used to arbitrate during first man selection when no load/store
exclusive instructions are usable.

For want of a better name, these are called "vlocks".  (I was
tempted to call them ballot locks, but "block" is way too confusing
an abbreviation...)

There is no function to wait for the lock to be released, and no
vlock_lock() function since we don't need these at the moment.
These could straightforwardly be added if vlocks get used for other
purposes.

For architectural correctness even Strongly-Ordered memory accesses
require barriers in order to guarantee that multiple CPUs have a
coherent view of the ordering of memory accesses.  Whether or not
this matters depends on hardware implementation details of the
memory system.  Since the purpose of this code is to provide a clean,
generic locking mechanism with no platform-specific dependencies the
barriers should be present to avoid unpleasant surprises on future
platforms.

Note:

  * When taking the lock, we don't care about implicit background
    memory operations and other signalling which may be pending,
    because those are not part of the critical section anyway.

    A DMB is sufficient to ensure correctly observed ordering if
    the explicit memory accesses in vlock_trylock.

  * No barrier is required after checking the election result,
    because the result is determined by the store to
    VLOCK_OWNER_OFFSET and is already globally observed due to the
    barriers in voting_end.  This means that global agreement on
    the winner is guaranteed, even before the winner is known
    locally.
Signed-off-by: NDave Martin <dave.martin@linaro.org>
Signed-off-by: NNicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>

This provides helper methods to coordinate between CPUs coming down
and CPUs going up, as well as documentation on the used algorithms,
so that cluster teardown and setup
operations are not done for a cluster simultaneously.

For use in the power_down() implementation:
  * __mcpm_cpu_going_down(unsigned int cluster, unsigned int cpu)
  * __mcpm_outbound_enter_critical(unsigned int cluster)
  * __mcpm_outbound_leave_critical(unsigned int cluster)
  * __mcpm_cpu_down(unsigned int cluster, unsigned int cpu)

The power_up_setup() helper should do platform-specific setup in
preparation for turning the CPU on, such as invalidating local caches
or entering coherency.  It must be assembler for now, since it must
run before the MMU can be switched on.  It is passed the affinity level
for which initialization should be performed.

Because the mcpm_sync_struct content is looked-up and modified
with the cache enabled or disabled depending on the code path, it is
crucial to always ensure proper cache maintenance to update main memory
right away.  The sync_cache_*() helpers are used to that end.

Also, in order to prevent a cached writer from interfering with an
adjacent non-cached writer, we ensure each state variable is located to
a separate cache line.

Thanks to Nicolas Pitre and Achin Gupta for the help with this
patch.
Signed-off-by: NDave Martin <dave.martin@linaro.org>
Signed-off-by: NNicolas Pitre <nico@linaro.org>
Reviewed-by: NWill Deacon <will.deacon@arm.com>

Fix spelling typos in Documentation/devicetree/bindings.
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

8250 driver has been (re)renamed to 8250_core.c by commit
9196d8ac. Follow that change to fix the
following error when building htmldocs:

  docproc: /work/cross/linux//drivers/tty/serial/8250/8250.c: No such file or directory
Acked-by: NRob landley <rob@landley.net>
Signed-off-by: NVincent Stehlé <v-stehle@ti.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

DM RAID:  Add message/status support for changing sync action

This patch adds a message interface to dm-raid to allow the user to more
finely control the sync actions being performed by the MD driver.  This
gives the user the ability to initiate "check" and "repair" (i.e. scrubbing).
Two additional fields have been appended to the status output to provide more
information about the type of sync action occurring and the results of those
actions, specifically: <sync_action> and <mismatch_cnt>.  These new fields
will always be populated.  This is essentially the device-mapper way of doing
what MD controls through the 'sync_action' sysfs file and shows through the
'mismatch_cnt' sysfs file.
Signed-off-by: NJonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NNeilBrown <neilb@suse.de>

MD:  Fix some typos/grammer in MD documentation
Reviewed-by: NPaul Menzel <paulepanter@users.sourceforge.net>
Signed-off-by: NJonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NNeilBrown <neilb@suse.de>

Support the BGR666 format on the IPUv3 parallel display.
Signed-off-by: NMarek Vasut <marex@denx.de>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds a dwc_platform.ko module that can be loaded by using
compatible = "snps,dwc2" in a device tree.
Signed-off-by: NMatthijs Kooijman <matthijs@stdin.nl>
Signed-off-by: NPaul Zimmerman <paulz@synopsys.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The usual scheme to initialize a cpuidle driver on a SMP is:

	cpuidle_register_driver(drv);
	for_each_possible_cpu(cpu) {
		device = &per_cpu(cpuidle_dev, cpu);
		cpuidle_register_device(device);
	}

This code is duplicated in each cpuidle driver.

On UP systems, it is done this way:

	cpuidle_register_driver(drv);
	device = &per_cpu(cpuidle_dev, cpu);
	cpuidle_register_device(device);

On UP, the macro 'for_each_cpu' does one iteration:

#define for_each_cpu(cpu, mask)                 \
        for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)

Hence, the initialization loop is the same for UP than SMP.

Beside, we saw different bugs / mis-initialization / return code unchecked in
the different drivers, the code is duplicated including bugs. After fixing all
these ones, it appears the initialization pattern is the same for everyone.

Please note, some drivers are doing dev->state_count = drv->state_count. This is
not necessary because it is done by the cpuidle_enable_device function in the
cpuidle framework. This is true, until you have the same states for all your
devices. Otherwise, the 'low level' API should be used instead with the specific
initialization for the driver.

Let's add a wrapper function doing this initialization with a cpumask parameter
for the coupled idle states and use it for all the drivers.

That will save a lot of LOC, consolidate the code, and the modifications in the
future could be done in a single place. Another benefit is the consolidation of
the cpuidle_device variable which is now in the cpuidle framework and no longer
spread accross the different arch specific drivers.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

TMP432 is similar to TMP431 with a second external temperature sensor.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Acked-by: NJean Delvare <khali@linux-fr.org>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This commit adds a driver that exposes all the radio related
functionality of the Si476x series of chips via the V4L2 subsystem.

[mchehab@redhat.com: change it to depends on MFD_SI476X_CORE instead of
 selecting it; vidioc_s_register now uses const struct]
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This adds new debug feature information so that the DAWR can be
identified by userspace tools like GDB.

Unfortunately the DAWR doesn't sit nicely into the current description
that ptrace provides to userspace via struct ppc_debug_info.  It doesn't
allow for specifying that only some ranges are possible or even the end
alignment constraints (DAWR only allows 512 byte wide ranges which can't
cross a 512 byte boundary).

After talking to Edjunior Machado (GDB ppc developer), it was decided
this was the best approach.  Just mark it as debug feature DAWR and
tools like GDB can internally decide the constraints.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>

PPC_PREP is marked as BROKEN since v2.6.15. Remove all PReP specific
code now.
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>

Per hpa, use crashkernel=X,high crashkernel=Y,low instead of
crashkernel_hign=X crashkernel_low=Y. As that could be extensible.

-v2: according to Vivek, change delimiter to ;
-v3: let hign and low only handle simple form and it conforms to
	description in kernel-parameters.txt
     still keep crashkernel=X override any crashkernel=X,high
        crashkernel=Y,low
-v4: update get_last_crashkernel returning and add more strict
     checking in parse_crashkernel_simple() found by HATAYAMA.
-v5: Change delimiter back to , according to HPA.
     also separate parse_suffix from parse_simper according to vivek.
	so we can avoid @pos in that path.
-v6: Tight the checking about crashkernel=X,highblahblah,high
     found by HTYAYAMA.

Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1366089828-19692-5-git-send-email-yinghai@kernel.orgAcked-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>