Currently, media presence polling for removeable block devices is done
from userland.  There are several issues with this.

* Polling is done by periodically opening the device.  For SCSI
  devices, the command sequence generated by such action involves a
  few different commands including TEST_UNIT_READY.  This behavior,
  while perfectly legal, is different from Windows which only issues
  single command, GET_EVENT_STATUS_NOTIFICATION.  Unfortunately, some
  ATAPI devices lock up after being periodically queried such command
  sequences.

* There is no reliable and unintrusive way for a userland program to
  tell whether the target device is safe for media presence polling.
  For example, polling for media presence during an on-going burning
  session can make it fail.  The polling program can avoid this by
  opening the device with O_EXCL but then it risks making a valid
  exclusive user of the device fail w/ -EBUSY.

* Userland polling is unnecessarily heavy and in-kernel implementation
  is lighter and better coordinated (workqueue, timer slack).

This patch implements framework for in-kernel disk event handling,
which includes media presence polling.

* bdops->check_events() is added, which supercedes ->media_changed().
  It should check whether there's any pending event and return if so.
  Currently, two events are defined - DISK_EVENT_MEDIA_CHANGE and
  DISK_EVENT_EJECT_REQUEST.  ->check_events() is guaranteed not to be
  called parallelly.

* gendisk->events and ->async_events are added.  These should be
  initialized by block driver before passing the device to add_disk().
  The former contains the mask of all supported events and the latter
  the mask of all events which the device can report without polling.
  /sys/block/*/events[_async] export these to userland.

* Kernel parameter block.events_dfl_poll_msecs controls the system
  polling interval (default is 0 which means disable) and
  /sys/block/*/events_poll_msecs control polling intervals for
  individual devices (default is -1 meaning use system setting).  Note
  that if a device can report all supported events asynchronously and
  its polling interval isn't explicitly set, the device won't be
  polled regardless of the system polling interval.

* If a device is opened exclusively with write access, event checking
  is automatically disabled until all write exclusive accesses are
  released.

* There are event 'clearing' events.  For example, both of currently
  defined events are cleared after the device has been successfully
  opened.  This information is passed to ->check_events() callback
  using @clearing argument as a hint.

* Event checking is always performed from system_nrt_wq and timer
  slack is set to 25% for polling.

* Nothing changes for drivers which implement ->media_changed() but
  not ->check_events().  Going forward, all drivers will be converted
  to ->check_events() and ->media_change() will be dropped.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

There's no reason for register_disk() and del_gendisk() to be in
fs/partitions/check.c.  Move both to genhd.c.  While at it, collapse
unlink_gendisk(), which was artificially in a separate function due to
genhd.c / check.c split, into del_gendisk().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

There's no user of the facility.  Kill it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

If priority is changed, continuing to check workload_expires and service tree
count of the previous workload does not make sense. We should always choose
the workload with lowest key of new priority in such case.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

It's able to check whether a CFQ group on a service tree by
checking "cfqg->rb_node". There's no need to maintain an
extra flag here.
Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

When a cfq group is running, it won't be dequeued from service tree, so
there's no need to store the active one in st->active. Just gid rid of it.
Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

Merge branch 'cleanup-bd_claim' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into for-2.6.38/core

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

The addition of CONFIG_SECURITY_DMESG_RESTRICT resulted in a build
failure when CONFIG_PRINTK=n.  This is because the capabilities code
which used the new option was built even though the variable in question
didn't exist.

The patch here fixes this by moving the capabilities checks out of the
LSM and into the caller.  All (known) LSMs should have been calling the
capabilities hook already so it actually makes the code organization
better to eliminate the hook altogether.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge branch 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6

* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6:
  arm: omap1: devices: need to return with a value
  OMAP1: camera.h: add missing include
  omap: dma: Add read-back to DMA interrupt handler to avoid spuriousinterrupts
  OMAP2: Devkit8000: Fix mmc regulator failure

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  hwmon: (w83795) Check for BEEP pin availability
  hwmon: (w83795) Clear intrusion alarm immediately
  hwmon: (w83795) Read the intrusion state properly
  hwmon: (w83795) Print the actual temperature channels as sources
  hwmon: (w83795) List all usable temperature sources
  hwmon: (w83795) Expose fan control method
  hwmon: (w83795) Fix fan control mode attributes
  hwmon: (lm95241) Check validity of input values
  hwmon: Change mail address of Hans J. Koch

* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  i2c: Sanity checks on adapter registration
  i2c: Mark i2c_adapter.id as deprecated
  i2c: Drivers shouldn't include <linux/i2c-id.h>
  i2c: Delete unused adapter IDs
  i2c: Remove obsolete cleanup for clientdata

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI: sysfs: fix printk warnings
  PCI: fix pci_bus_alloc_resource() hang, prefer positive decode
  PCI: read current power state at enable time
  PCI: fix size checks for mmap() on /proc/bus/pci files
  x86/PCI: coalesce overlapping host bridge windows
  PCI hotplug: ibmphp: Add check to prevent reading beyond mapped area

Make sure I2C adapters being registered have the required struct
fields set. If they don't, problems will happen later.
Signed-off-by: Jean Delvare <khali@linux-fr.org>

It's about time to make it clear that i2c_adapter.id is deprecated.
Hopefully this will remind the last user to move over to a different
strategy.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Hans Verkuil <hverkuil@xs4all.nl>

Drivers don't need to include <linux/i2c-id.h>, especially not when
they don't use anything that header file provides.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Michael Hunold <michael@mihu.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>

Delete unused I2C adapter IDs. Special cases are:

* I2C_HW_B_RIVA was still set in driver rivafb, however no other
  driver is ever looking for this value, so we can safely remove it.
* I2C_HW_B_HDPVR is used in staging driver lirc_zilog, however no
  adapter ID is ever set to this value, so the code in question never
  runs. As the code additionally expects that I2C_HW_B_HDPVR may not
  be defined, we can delete it now and let the lirc_zilog driver
  maintainer rewrite this piece of code.

Big thanks for Hans Verkuil for doing all the hard work :)
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Hans Verkuil <hverkuil@xs4all.nl>

A few new i2c-drivers came into the kernel which clear the clientdata-pointer
on exit. This is obsolete meanwhile, so fix it and hope the word will spread.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

Move the logging bits from kernel.h into printk.h so that
there is a bit more logical separation of the generic from
the printk logging specific parts.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The fix in commit 6b4e81db ("i8k: Tell gcc that *regs gets
clobbered") to work around the gcc miscompiling i8k.c to add "+m
(*regs)" caused register pressure problems and a build failure.

Changing the 'asm' statement to 'asm volatile' instead should prevent
that and works around the gcc bug as well, so we can remove the "+m".

[ Background on the gcc bug: a memory clobber fails to mark the function
  the asm resides in as non-pure (aka "__attribute__((const))"), so if
  the function does nothing else that triggers the non-pure logic, gcc
  will think that that function has no side effects at all. As a result,
  callers will be mis-compiled.

  Adding the "+m" made gcc see that it's not a pure function, and so
  does "asm volatile". The problem was never really the need to mark
  "*regs" as changed, since the memory clobber did that part - the
  problem was just a bug in the gcc "pure" function analysis  - Linus ]
Signed-off-by: Jim Bos <jim876@xs4all.nl>
Acked-by: Jakub Jelinek <jakub@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

On the W83795ADG, there's a single pin for BEEP and OVT#, so you
can't have both. Check the configuration and don't create beep
attributes when BEEP pin is not available.

The W83795G has a dedicated BEEP pin so the functionality is always
available there.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>

When asked to clear the intrusion alarm, do so immediately. We have to
invalidate the cache to make sure the new status will be read. But we
also have to read from the status register once to clear the pending
alarm, as writing to CLR_CHS surprising won't clear it automatically.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>

We can't read the intrusion state from the real-time alarm registers
as we do for all other alarm flags, because real-time alarm bits don't
stick (by definition) and the intrusion state has to stick until
explicitly cleared (otherwise it has little value.)

So we have to use the interrupt status register instead, which is read
from the same address but with a configuration bit flipped in another
register.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>

Don't expose raw register values to user-space. Decode and encode
temperature channels selected as temperature sources as needed.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>

Temperature sources are not correlated directly with temperature
channels. A look-up table is required to find out which temperature
sources can be used depending on which temperature channels (both
analog and digital) are enabled.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>

Expose fan control method (DC vs. PWM) using the standard sysfs
attributes. I've made it read-only as the board should be wired for
a given mode, the BIOS should have set up the chip for this mode, and
you shouldn't have to change it. But it would be easy enough to make
it changeable if someone comes up with a use case.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>

There were two bugs:
* Speed cruise mode was improperly reported for all fans but fan1.
* Fan control method (PWM vs. DC) was mixed with the control mode.
  It will be added back as a separate attribute, as per the standard
  sysfs interface.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>

This clears the following build-time warnings I was seeing:

drivers/hwmon/lm95241.c: In function "set_interval":
drivers/hwmon/lm95241.c:132:15: warning: ignoring return value of "strict_strtol", declared with attribute warn_unused_result
drivers/hwmon/lm95241.c: In function "set_max2":
drivers/hwmon/lm95241.c:278:1: warning: ignoring return value of "strict_strtol", declared with attribute warn_unused_result
drivers/hwmon/lm95241.c: In function "set_max1":
drivers/hwmon/lm95241.c:277:1: warning: ignoring return value of "strict_strtol", declared with attribute warn_unused_result
drivers/hwmon/lm95241.c: In function "set_min2":
drivers/hwmon/lm95241.c:249:1: warning: ignoring return value of "strict_strtol", declared with attribute warn_unused_result
drivers/hwmon/lm95241.c: In function "set_min1":
drivers/hwmon/lm95241.c:248:1: warning: ignoring return value of "strict_strtol", declared with attribute warn_unused_result
drivers/hwmon/lm95241.c: In function "set_type2":
drivers/hwmon/lm95241.c:220:1: warning: ignoring return value of "strict_strtol", declared with attribute warn_unused_result
drivers/hwmon/lm95241.c: In function "set_type1":
drivers/hwmon/lm95241.c:219:1: warning: ignoring return value of "strict_strtol", declared with attribute warn_unused_result

This also fixes a small race in set_interval() as a side effect: by
working with a temporary local variable we prevent data->interval from
being accessed at a time it contains the interval value in the wrong
unit.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Davide Rizzo <elpa.rizzo@gmail.com>

My old mail address doesn't exist anymore. This changes all occurrences
to my new address.
Signed-off-by: Hans J. Koch <hjk@hansjkoch.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

o Allow hierarchical cgroup creation for blkio controller

o Currently we disallow it as both the io controller policies (throttling
  as well as proportion bandwidth) do not support hierarhical accounting
  and control. But the flip side is that blkio controller can not be used with
  libvirt as libvirt creates a cgroup hierarchy deeper than 1 level.

  <top-level-cgroup-dir>/<controller>/libvirt/qemu/<virtual-machine-groups>

o So this patch will allow creation of cgroup hierarhcy but at the backend
  everything will be treated as flat. So if somebody created a an hierarchy
  like as follows.

			root
			/  \
		     test1 test2
			|
		     test3

  CFQ and throttling will practically treat all groups at same level.

				pivot
			     /  |   \  \
			root  test1 test2  test3

o Once we have actual support for hierarchical accounting and control
  then we can introduce another cgroup tunable file "blkio.use_hierarchy"
  which will be 0 by default but if user wants to enforce hierarhical
  control then it can be set to 1. This way there should not be any
  ABI problems down the line.

o The only not so pretty part is introduction of extra file "use_hierarchy"
  down the line. Kame-san had mentioned that hierarhical accounting is
  expensive in memory controller hence they keep it off by default. I
  suspect same will be the case for IO controller also as for each IO
  completion we shall have to account IO through hierarchy up to the root.
  if yes, then it probably is not a very bad idea to introduce this extra
  file so that it will be used only when somebody needs it and some people
  might enable hierarchy only in part of the hierarchy.

o This is how basically memory controller also uses "use_hierarhcy" and
  they also allowed creation of hierarchies when actual backend support
  was not available.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Reviewed-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Reviewed-by: Ciju Rajan K <ciju@linux.vnet.ibm.com>
Tested-by: Ciju Rajan K <ciju@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

Cast pci_resource_start() and pci_resource_len() to u64 for printk.

drivers/pci/pci-sysfs.c:753: warning: format '%16Lx' expects type 'long long unsigned int', but argument 9 has type 'resource_size_t'
drivers/pci/pci-sysfs.c:753: warning: format '%16Lx' expects type 'long long unsigned int', but argument 10 has type 'resource_size_t'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
  GFS2: Fix inode deallocation race

Merge branch 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung

* 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
  ARM: SAMSUNG: Fix HAVE_S3C_RTC warnings
  ARM: SAMSUNG: Fix HAVE_S3C2410_I2C warnings
  ARM: SAMSUNG: Fix HAVE_S3C2410_WATCHDOG warnings

Merge branch 'fbdev-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/fbdev-2.6

* 'fbdev-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/fbdev-2.6:
  fsl-diu-fb: drop dead ioctl define
  MAINTAINERS: Add an fbdev git tree entry.
  OMAP: DSS: Fix documentation regarding 'vram' kernel parameter
  OMAP: VRAM: Fix boot-time memory allocation
  OMAP: VRAM: improve VRAM error prints
  sisfb: limit POST memory test according to PCI resource length
  fbdev: sh_mobile_lcdc: use correct number of modes, when using the default
  fbdev: sh_mobile_lcdc: use the standard CEA-861 720p timing
  fbdev: sh_mobile_hdmi: properly clean up modedb on monitor unplug

Merge branches 'sh-fixes-for-linus' and 'rmobile-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6

* 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
  sh: intc: Fix up build failure introduced by radix tree changes.
  MAINTAINERS: update the sh git tree entry.
  sh: clkfwk: fix up compiler warnings.
  sh: intc: Fix up initializers for gcc 4.5.
  rtc: rtc-sh - fix a memory leak

* 'rmobile-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
  ARM: mach-shmobile: ap4evb: add fsib 44100Hz rate
  MAINTAINERS: update the ARM SH-Mobile git tree entry.
  ARM: mach-shmobile: ap4evb: Mark NOR boot loader partitions read-only.
  ARM: mach-shmobile: intc-sh7372: fix interrupt number

This area of the code has always been a bit delicate due to the
subtleties of lock ordering. The problem is that for "normal"
alloc/dealloc, we always grab the inode locks first and the rgrp lock
later.

In order to ensure no races in looking up the unlinked, but still
allocated inodes, we need to hold the rgrp lock when we do the lookup,
which means that we can't take the inode glock.

The solution is to borrow the technique already used by NFS to solve
what is essentially the same problem (given an inode number, look up
the inode carefully, checking that it really is in the expected
state).

We cannot do that directly from the allocation code (lock ordering
again) so we give the job to the pre-existing delete workqueue and
carry on with the allocation as normal.

If we find there is no space, we do a journal flush (required anyway
if space from a deallocation is to be released) which should block
against the pending deallocations, so we should always get the space
back.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>