Commit Graph

3751 Commits

Author SHA1 Message Date
Thomas Gleixner 691cc54c7d debugobjects: add documentation
Add a DocBook for debugobjects.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:53 -07:00
Thomas Gleixner 3ac7fe5a4a infrastructure to debug (dynamic) objects
We can see an ever repeating problem pattern with objects of any kind in the
kernel:

1) freeing of active objects
2) reinitialization of active objects

Both problems can be hard to debug because the crash happens at a point where
we have no chance to decode the root cause anymore.  One problem spot are
kernel timers, where the detection of the problem often happens in interrupt
context and usually causes the machine to panic.

While working on a timer related bug report I had to hack specialized code
into the timer subsystem to get a reasonable hint for the root cause.  This
debug hack was fine for temporary use, but far from a mergeable solution due
to the intrusiveness into the timer code.

The code further lacked the ability to detect and report the root cause
instantly and keep the system operational.

Keeping the system operational is important to get hold of the debug
information without special debugging aids like serial consoles and special
knowledge of the bug reporter.

The problems described above are not restricted to timers, but timers tend to
expose it usually in a full system crash.  Other objects are less explosive,
but the symptoms caused by such mistakes can be even harder to debug.

Instead of creating specialized debugging code for the timer subsystem a
generic infrastructure is created which allows developers to verify their code
and provides an easy to enable debug facility for users in case of trouble.

The debugobjects core code keeps track of operations on static and dynamic
objects by inserting them into a hashed list and sanity checking them on
object operations and provides additional checks whenever kernel memory is
freed.

The tracked object operations are:
- initializing an object
- adding an object to a subsystem list
- deleting an object from a subsystem list

Each operation is sanity checked before the operation is executed and the
subsystem specific code can provide a fixup function which allows to prevent
the damage of the operation.  When the sanity check triggers a warning message
and a stack trace is printed.

The list of operations can be extended if the need arises.  For now it's
limited to the requirements of the first user (timers).

The core code enqueues the objects into hash buckets.  The hash index is
generated from the address of the object to simplify the lookup for the check
on kfree/vfree.  Each bucket has it's own spinlock to avoid contention on a
global lock.

The debug code can be compiled in without being active.  The runtime overhead
is minimal and could be optimized by asm alternatives.  A kernel command line
option enables the debugging code.

Thanks to Ingo Molnar for review, suggestions and cleanup patches.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:53 -07:00
Samuel Thibault f7511d5f66 Basic braille screen reader support
This adds a minimalistic braille screen reader support.  This is meant to
be used by blind people e.g.  on boot failures or when / cannot be mounted
etc and thus the userland screen readers can not work.

[akpm@linux-foundation.org: fix exports]
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Jiri Kosina <jikos@jikos.cz>
Cc: Dmitry Torokhov <dtor@mail.ru>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:52 -07:00
Miklos Szeredi b88473f73e mm: document missing fields for /proc/meminfo
A few fields in /proc/meminfo were not documented.  Fix.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Miklos Szeredi 76f1418b48 mm: bdi: move statistics to debugfs
Move BDI statistics to debugfs:

   /sys/kernel/debug/bdi/<bdi>/stats

Use postcore_initcall() to initialize the sysfs class and debugfs,
because debugfs is initialized in core_initcall().

Update descriptions in ABI documentation.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Peter Zijlstra a42dde0415 mm: bdi: allow setting a maximum for the bdi dirty limit
Add "max_ratio" to /sys/class/bdi.  This indicates the maximum percentage of
the global dirty threshold allocated to this bdi.

[mszeredi@suse.cz]

 - fix parsing in max_ratio_store().
 - export bdi_set_max_ratio() to modules
 - limit bdi_dirty with bdi->max_ratio
 - document new sysfs attribute

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Peter Zijlstra 189d3c4a94 mm: bdi: allow setting a minimum for the bdi dirty limit
Under normal circumstances each device is given a part of the total write-back
cache that relates to its current avg writeout speed in relation to the other
devices.

min_ratio - allows one to assign a minimum portion of the write-back cache to
a particular device.  This is useful in situations where you might want to
provide a minimum QoS.  (One request for this feature came from flash based
storage people who wanted to avoid writing out at all costs - they of course
needed some pdflush hacks as well)

max_ratio - allows one to assign a maximum portion of the dirty limit to a
particular device.  This is useful in situations where you want to avoid one
device taking all or most of the write-back cache.  Eg.  an NFS mount that is
prone to get stuck, or a FUSE mount which you don't trust to play fair.

Add "min_ratio" to /sys/class/bdi.  This indicates the minimum percentage of
the global dirty threshold allocated to this bdi.

[mszeredi@suse.cz]

 - fix parsing in min_ratio_store()
 - document new sysfs attribute

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Peter Zijlstra cf0ca9fe5d mm: bdi: export BDI attributes in sysfs
Provide a place in sysfs (/sys/class/bdi) for the backing_dev_info object.
This allows us to see and set the various BDI specific variables.

In particular this properly exposes the read-ahead window for all relevant
users and /sys/block/<block>/queue/read_ahead_kb should be deprecated.

With patient help from Kay Sievers and Greg KH

[mszeredi@suse.cz]

 - split off NFS and FUSE changes into separate patches
 - document new sysfs attributes under Documentation/ABI
 - do bdi_class_init as a core_initcall, otherwise the "default" BDI
   won't be initialized
 - remove bdi_init_fmt macro, it's not used very much

[akpm@linux-foundation.org: fix ia64 warning]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Greg KH <greg@kroah.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:49 -07:00
Pavel Emelyanov 5cd204550b Deprecate find_task_by_pid()
There are some places that are known to operate on tasks'
global pids only:

* the rest_init() call (called on boot)
* the kgdb's getthread
* the create_kthread() (since the kthread is run in init ns)

So use the find_task_by_pid_ns(..., &init_pid_ns) there
and schedule the find_task_by_pid for removal.

[sukadev@us.ibm.com: Fix warning in kernel/pid.c]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:48 -07:00
Randy Dunlap 957d33fc1a docbook: fix fatal rapidio yet again (and more to come)
Don't refer to file that no longer exists:
docproc: linux-2.6.25-git14/arch/powerpc/kernel/rio.c: No such file or directory

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 20:40:00 -07:00
Linus Torvalds 2d5e3e8d28 Merge git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb
* git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb: (28 commits)
  V4L-DVB(7789a): cx18: fix symbol conflict with ivtv driver
  V4L/DVB (7789): tuner: remove static dependencies on analog tuner sub-modules
  V4L/DVB (7785): [2.6 patch] make mt9{m001,v022}_controls[] static
  V4L/DVB (7786): cx18: new driver for the Conexant CX23418 MPEG encoder chip
  V4L/DVB (7783): drivers/media/dvb/frontends/s5h1420.c: printk fix
  V4L/DVB (7782): pvrusb2: Driver is no longer experimental
  V4L/DVB (7781): pvrusb2-dvb: include dvb support by default and update Kconfig help text
  V4L/DVB (7780): pvrusb2: always enable support for OnAir Creator / HDTV USB2
  V4L/DVB (7779): pvrusb2-dvb: quiet down noise in kernel log for feed debug
  Rename common tuner Kconfig names to use the same
  Fix V4L/DVB core help messages
  V4L/DVB (7769): Move other terrestrial tuners to common/tuners
  V4L/DVB (7768): reorganize some DVB-S Kconfig items
  V4L/DVB(7767): Move tuners to common/tuners
  V4L/DVB (7766): saa7134: add another PCI ID for Beholder M6
  V4L/DVB (7765): Add support for Beholder BeholdTV H6
  V4L/DVB (7763): ivtv: add tuner support for the AverMedia M116
  V4L/DVB (7762): ivtv: fix tuner detection for PAL-N/Nc
  V4L/DVB (7761): ivtv: increase the DMA timeout from 100 to 300 ms
  V4L/DVB (7759): ivtv: increase version number to 1.2.1
  ...
2008-04-29 14:53:40 -07:00
Hans Verkuil 1c1e45d17b V4L/DVB (7786): cx18: new driver for the Conexant CX23418 MPEG encoder chip
Many thanks to Steve Toth from Hauppauge and Nattu Dakshinamurthy from
Conexant for their support. I am in particular thankful to Hauppauge
since without their help this driver would not exist. It should also
be noted that Steve did the work to get the DVB part up and running.
Thank you!

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Steven Toth <stoth@hauppauge.com>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: G. Andrew Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-29 18:41:41 -03:00
Igor Kuznetsov 5fe95e0b86 V4L/DVB (7766): saa7134: add another PCI ID for Beholder M6
Signed-off-by: Igor Kuznetsov <igk@igk.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-29 18:41:37 -03:00
Igor Kuznetsov 025052716d V4L/DVB (7765): Add support for Beholder BeholdTV H6
Signed-off-by: Igor Kuznetsov <igk@igk.ru>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-29 18:41:36 -03:00
Jean Delvare d2653e9273 i2c: Add support for device alias names
Based on earlier work by Jon Smirl and Jochen Friedrich.

This patch allows new-style i2c chip drivers to have alias names using
the official kernel aliasing system and MODULE_DEVICE_TABLE(). At this
point, the old i2c driver binding scheme (driver_name/type) is still
supported.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Jochen Friedrich <jochen@scram.de>
Cc: Jon Smirl <jonsmirl@gmail.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
2008-04-29 23:11:39 +02:00
Linus Torvalds a217656cb2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (21 commits)
  pciehp: fix error message about getting hotplug control
  pci/irq: let pci_device_shutdown to call pci_msi_shutdown v2
  pci/irq: restore mask_bits in msi shutdown -v3
  doc: replace yet another dev with pdev for consistency in DMA-mapping.txt
  PCI: don't expose struct pci_vpd to userspace
  doc: fix an incorrect suggestion to pass NULL for PCI like buses
  Consistently use pdev as the variable of type struct pci_dev *.
  pciehp: Fix command write
  shpchp: fix slot name
  make pciehp_acpi_get_hp_hw_control_from_firmware()
  pciehp: Clean up pcie_init()
  pciehp: Mask hotplug interrupt at controller release
  pciehp: Remove useless hotplug interrupt enabling
  pciehp: Fix wrong slot capability check
  pciehp: Fix wrong slot control register access
  pciehp: Add missing memory barrier
  pciehp: Fix interrupt event handlig
  pciehp: fix slot name
  Update MAINTAINERS with location of PCI tree
  PCI: Add Intel SCH PCI IDs
  ...
2008-04-29 10:17:59 -07:00
Linus Torvalds 25a025863e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
  [ALSA] soc - wm9712 - checkpatch fixes
  [ALSA] pcsp - Fix more dependency
  [ALSA] hda - Add support of Medion RIM 2150
  [ALSA] ASoC: Add drivers for the Texas Instruments OMAP processors
  [ALSA] ice1724 - Enable watermarks
  [ALSA] Add MPU401_INFO_NO_ACK bitflag
2008-04-29 09:38:52 -07:00
Takashi Iwai df99cd334e [ALSA] hda - Add support of Medion RIM 2150
Added the support of Medion RIM 2150 laptop with ALC880 codec.
ALSA bug#3708:
	https://bugtrack.alsa-project.org/alsa-bug/view.php?id=3708

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2008-04-29 19:01:57 +02:00
Linus Torvalds 1f43c53930 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-fixes
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86-fixes:
  x86: fix PCI MSI breaks when booting with nosmp
  x86: vget_cycles() __always_inline
  x86: add more boot protocol documentation
  bootprotocol: cleanup
  x86: fix warning in "x86: clean up vSMP detection"
  x86: !x & y typo in mtrr code
2008-04-29 09:03:19 -07:00
Matti Linnanvuori 2768f92c06 doc: replace yet another dev with pdev for consistency in DMA-mapping.txt
Replace "dev" with "pdev" for consistency in DMA-mapping.txt.

Signed-off-by: Matti Linnanvuori <mattilinnanvuori@yahoo.com>
Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
2008-04-29 08:55:01 -07:00
Linus Torvalds 44473d9913 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] state info wrong after resume
  [CPUFREQ] allow use of the powersave governor as the default one
  [CPUFREQ] document the currently undocumented parts of the sysfs interface
  [CPUFREQ] expose cpufreq coordination requirements regardless of coordination mechanism
2008-04-29 08:18:49 -07:00
Tim Gardner 8c4dd60682 edd: add default mode CONFIG_EDD_OFF=n, override with edd={on,off}
Add a kernel parameter option to 'edd' to enable/disable BIOS Enhanced Disk
Drive Services.  CONFIG_EDD_OFF disables EDD while still compiling EDD into
the kernel.  Default behavior can be forced using 'edd=on' or 'edd=off' as
a kernel parameter.

[akpm@linux-foundation.org: fix kernel-parameters.txt]
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Matt Domsch <Matt_Domsch@dell.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:23 -07:00
David Howells 0b77f5bfb4 keys: make the keyring quotas controllable through /proc/sys
Make the keyring quotas controllable through /proc/sys files:

 (*) /proc/sys/kernel/keys/root_maxkeys
     /proc/sys/kernel/keys/root_maxbytes

     Maximum number of keys that root may have and the maximum total number of
     bytes of data that root may have stored in those keys.

 (*) /proc/sys/kernel/keys/maxkeys
     /proc/sys/kernel/keys/maxbytes

     Maximum number of keys that each non-root user may have and the maximum
     total number of bytes of data that each of those users may have stored in
     their keys.

Also increase the quotas as a number of people have been complaining that it's
not big enough.  I'm not sure that it's big enough now either, but on the
other hand, it can now be set in /etc/sysctl.conf.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: <kwc@citi.umich.edu>
Cc: <arunsr@cse.iitk.ac.in>
Cc: <dwalsh@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:17 -07:00
David Howells 70a5bb72b5 keys: add keyctl function to get a security label
Add a keyctl() function to get the security label of a key.

The following is added to Documentation/keys.txt:

 (*) Get the LSM security context attached to a key.

	long keyctl(KEYCTL_GET_SECURITY, key_serial_t key, char *buffer,
		    size_t buflen)

     This function returns a string that represents the LSM security context
     attached to a key in the buffer provided.

     Unless there's an error, it always returns the amount of data it could
     produce, even if that's too big for the buffer, but it won't copy more
     than requested to userspace. If the buffer pointer is NULL then no copy
     will take place.

     A NUL character is included at the end of the string if the buffer is
     sufficiently big.  This is included in the returned count.  If no LSM is
     in force then an empty string will be returned.

     A process must have view permission on the key for this function to be
     successful.

[akpm@linux-foundation.org: declare keyctl_get_security()]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:16 -07:00
David Howells 4a38e122e2 keys: allow the callout data to be passed as a blob rather than a string
Allow the callout data to be passed as a blob rather than a string for
internal kernel services that call any request_key_*() interface other than
request_key().  request_key() itself still takes a NUL-terminated string.

The functions that change are:

	request_key_with_auxdata()
	request_key_async()
	request_key_async_with_auxdata()

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:16 -07:00
Randy Dunlap 02d15c4322 doc: fix DMA-API function parameters
Fix kernel bugzilla #10388.

DMA-API.txt has wrong argument type for some functions.  It uses struct device
but should use struct pci_dev.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:12 -07:00
Arthur Kepner a75b0a2f68 dma: document dma_*map*_attrs() interfaces
Document the new dma_*map*_attrs() functions.

[markn@au1.ibm.com: fix up for dma-add-dma_map_attrs-interfaces and update docs]
Signed-off-by: Arthur Kepner <akepner@sgi.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Roland Dreier <rdreier@cisco.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Grant Grundler <grundler@parisc-linux.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:11 -07:00
Paul Menage 786083667e Cpuset hardwall flag: add a mem_hardwall flag to cpusets
This flag provides the hardwalling properties of mem_exclusive, without
enforcing the exclusivity.  Either mem_hardwall or mem_exclusive is sufficient
to prevent GFP_KERNEL allocations from passing outside the cpuset's assigned
nodes.

Signed-off-by: Paul Menage <menage@google.com>
Acked-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:11 -07:00
Pavel Emelyanov faebe9fdf3 memcgroups: add a document describing the resource counter abstraction
The resource counter is supposed to facilitate the resource accounting of
arbitrary resource (and it already does this for memory controller).

However, it is about to be used in other resources controllers (swap, kernel
memory, networking, etc), so provide a doc describing how to work with it.
This will eliminate all the possible future duplications in the appropriate
controllers' docs.

Fixed errors pointed out by Randy.

[akpm@linux-foundation.org: fix documentation tpyo]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:10 -07:00
Li Zefan e8d55fdeb8 cgroups: simplify init_subsys()
We are at system boot and there is only 1 cgroup group (i,e, init_css_set), so
we don't need to run through the css_set linked list.  Neither do we need to
run through the task list, since no processes have been created yet.

Also referring to a comment in cgroup.h:

struct css_set
{
	...
	/*
	 * Set of subsystem states, one for each subsystem. This array
	 * is immutable after creation apart from the init_css_set
	 * during subsystem registration (at boot time).
	 */
	struct cgroup_subsys_state *subsys[CGROUP_SUBSYS_COUNT];
}

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Reviewed-by: Paul Menage <menage@google.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:10 -07:00
Serge E. Hallyn 08ce5f16ee cgroups: implement device whitelist
Implement a cgroup to track and enforce open and mknod restrictions on device
files.  A device cgroup associates a device access whitelist with each cgroup.
 A whitelist entry has 4 fields.  'type' is a (all), c (char), or b (block).
'all' means it applies to all types and all major and minor numbers.  Major
and minor are either an integer or * for all.  Access is a composition of r
(read), w (write), and m (mknod).

The root device cgroup starts with rwm to 'all'.  A child devcg gets a copy of
the parent.  Admins can then remove devices from the whitelist or add new
entries.  A child cgroup can never receive a device access which is denied its
parent.  However when a device access is removed from a parent it will not
also be removed from the child(ren).

An entry is added using devices.allow, and removed using
devices.deny.  For instance

	echo 'c 1:3 mr' > /cgroups/1/devices.allow

allows cgroup 1 to read and mknod the device usually known as
/dev/null.  Doing

	echo a > /cgroups/1/devices.deny

will remove the default 'a *:* mrw' entry.

CAP_SYS_ADMIN is needed to change permissions or move another task to a new
cgroup.  A cgroup may not be granted more permissions than the cgroup's parent
has.  Any task can move itself between cgroups.  This won't be sufficient, but
we can decide the best way to adequately restrict movement later.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix may-be-used-uninitialized warning]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Acked-by: James Morris <jmorris@namei.org>
Looks-good-to: Pavel Emelyanov <xemul@openvz.org>
Cc: Daniel Hokka Zakrisson <daniel@hozac.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:09 -07:00
Andres Salomon 3ef0e1f8ca x86: olpc: add One Laptop Per Child architecture support
This adds support for OLPC XO hardware.  Open Firmware on XOs don't contain
the VSA, so it is necessary to emulate the PCI BARs in the kernel.  This also
adds functionality for running EC commands, and a CONFIG_OLPC.

A number of OLPC drivers depend upon CONFIG_OLPC.

olpc_ec_timeout is a hack to work around Embedded Controller bugs.

[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: geode_has_vsa build fix]
[akpm@linux-foundation.org: olpc_register_battery_callback doesn't exist]
Signed-off-by: Andres Salomon <dilinger@debian.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:07 -07:00
Rik van Riel 5045bcae0f sysrq: add show-backtrace-on-all-cpus function
SysRQ-P is not always useful on SMP systems, since it usually ends up showing
the backtrace of a CPU that is doing just fine, instead of the backtrace of
the CPU that is having problems.

This patch adds SysRQ show-all-cpus(L), which shows the backtrace of every
active CPU in the system.  It skips idle CPUs because some SMP systems are
just too large and we already know what the backtrace of the idle task looks
like.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Rik van Riel <riel@redhat.com>
Randy Dunlap <randy.dunlap@oracle.com>
Cc: <lwoodman@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:03 -07:00
Nur Hussein 95b570c9ce Taint kernel after WARN_ON(condition)
The kernel is sent to tainted within the warn_on_slowpath() function, and
whenever a warning occurs the new taint flag 'W' is set.  This is useful to
know if a warning occurred before a BUG by preserving the warning as a flag
in the taint state.

This does not work on architectures where WARN_ON has its own definition.
These archs are:
	1. s390
	2. superh
	3. avr32
	4. parisc

The maintainers of these architectures have been added in the Cc: list
in this email to alert them to the situation.

The documentation in oops-tracing.txt has been updated to include the
new flag.

Signed-off-by: Nur Hussein <nurhussein@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:05:59 -07:00
Ian Campbell 4c0587e6e4 x86: add more boot protocol documentation
Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-29 13:45:24 +02:00
Linus Torvalds f05c463be5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild:
  kconfig: add named choice group
  kconfig: fix choice dependency check
  kconifg: 'select' considered less evil
  dontdiff: ignore timeconst.h
  dontdiff: add modules.order
  kbuild: fix unportability in gen_initramfs_list.sh
  kbuild: fix help output to show correct arch
  kbuild: show defconfig subdirs in make help
  kconfig: reversed borderlines in inputbox
2008-04-28 17:29:43 -07:00
Linus Torvalds e97e386b12 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
  slub: pack objects denser
  slub: Calculate min_objects based on number of processors.
  slub: Drop DEFAULT_MAX_ORDER / DEFAULT_MIN_OBJECTS
  slub: Simplify any_slab_object checks
  slub: Make the order configurable for each slab cache
  slub: Drop fallback to page allocator method
  slub: Fallback to minimal order during slab page allocation
  slub: Update statistics handling for variable order slabs
  slub: Add kmem_cache_order_objects struct
  slub: for_each_object must be passed the number of objects in a slab
  slub: Store max number of objects in the page struct.
  slub: Dump list of objects not freed on kmem_cache_close()
  slub: free_list() cleanup
  slub: improve kmem_cache_destroy() error message
  slob: fix bug - when slob allocates "struct kmem_cache", it does not force alignment.
2008-04-28 14:08:56 -07:00
Matthew Wilcox dfecbec8b5 kconifg: 'select' considered less evil
While select should be used with care, it is not actually evil.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-04-28 22:59:31 +02:00
Ben Dooks beda8ae716 dontdiff: ignore timeconst.h
Ignore the autobuilt kernel/timeconst.h when
using diff on an built kernel tree.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-04-28 22:51:56 +02:00
Ben Dooks a72a431bf8 dontdiff: add modules.order
Add modules.order to the list of files that
shoud be ignored when using diff on a built
kernel tree.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-04-28 22:51:55 +02:00
Darrick J. Wong 605400a8ab [CPUFREQ] document the currently undocumented parts of the sysfs interface
There is a description of some of the sysfs files.  However, there are some
that are not mentioned in the documentation, so add them to the user's guide.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2008-04-28 16:27:08 -04:00
Randy Dunlap a04140e17b docbook: fix bitops fatal filename error
bitops source file was renamed, so fix docbook for that.
docproc: linux-2.6.25-git11/include/asm-x86/bitops_32.h: No such file or directory

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 10:26:51 -07:00
Matti Linnanvuori 97a34eb77c doc: fix an incorrect suggestion to pass NULL for PCI like buses
Fix an incorrect suggestion to pass NULL to pci_alloc_consistent
for PCI like buses where devices don't have struct pci_dev (like ISA, EISA).

Signed-off-by: Matti Linnanvuori <mattilinnanvuori@yahoo.com>
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
2008-04-28 10:07:28 -07:00
Matti Linnanvuori 819e32377e Consistently use pdev as the variable of type struct pci_dev *.
Update DMA mapping documentation to use 'pdev' rather than 'dev' in
example code that calls routines expecting 'struct pci_device *', since 'dev'
might make readers think they're passing 'struct device *' parameters.
Bug 10397.

Signed-off-by: Matti Linnanvuori <mattilinnanvuori@yahoo.com>
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2008-04-28 09:48:24 -07:00
OGAWA Hirofumi 1ae43f826b fat: Add allow_utime option
Normally utime(2) checks current process is owner of the file, or it
has CAP_FOWNER capability.  But FAT filesystem doesn't have uid/gid as
on disk info, so normal check is too unflexible.

With this option you can relax it.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:47 -07:00
Dan Williams 8b3e6cdc53 md: introduce get_priority_stripe() to improve raid456 write performance
Improve write performance by preventing the delayed_list from dumping all its
stripes onto the handle_list in one shot.  Delayed stripes are now further
delayed by being held on the 'hold_list'.  The 'hold_list' is bypassed when:

  * a STRIPE_IO_STARTED stripe is found at the head of 'handle_list'
  * 'handle_list' is empty and i/o is being done to satisfy full stripe-width
    write requests
  * 'bypass_count' is less than 'bypass_threshold'.  By default the threshold
    is 1, i.e. every other stripe handled is a preread stripe provided the
    top two conditions are false.

Benchmark data:
System: 2x Xeon 5150, 4x SATA, mem=1GB
Baseline: 2.6.24-rc7
Configuration: mdadm --create /dev/md0 /dev/sd[b-e] -n 4 -l 5 --assume-clean
Test1: dd if=/dev/zero of=/dev/md0 bs=1024k count=2048
  * patched:  +33% (stripe_cache_size = 256), +25% (stripe_cache_size = 512)

Test2: tiobench --size 2048 --numruns 5 --block 4096 --block 131072 (XFS)
  * patched: +13%
  * patched + preread_bypass_threshold = 0: +37%

Changes since v1:
* reduce bypass_threshold from (chunk_size / sectors_per_chunk) to (1) and
  make it configurable.  This defaults to fairness and modest performance
  gains out of the box.
Changes since v2:
* [neilb@suse.de]: kill STRIPE_PRIO_HI and preread_needed as they are not
  necessary, the important change was clearing STRIPE_DELAYED in
  add_stripe_bio and this has been moved out to make_request for the hang
  fix.
* [neilb@suse.de]: simplify get_priority_stripe
* [dan.j.williams@intel.com]: reset the bypass_count when ->hold_list is
  sampled empty (+11%)
* [dan.j.williams@intel.com]: decrement the bypass_count at the detection
  of stripes being naturally promoted off of hold_list +2%.  Note, resetting
  bypass_count instead of decrementing on these events yields +4% but that is
  probably too aggressive.
Changes since v3:
* cosmetic fixups

Tested-by: James W. Laferriere <babydr@baby-dragons.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:42 -07:00
Maik Broemme 0e170c72c0 fbdev: intelfb: add support for the Intel Integrated Graphics Controller 965G/965GM
Add support for the 965G and 965GM graphic chipsets to the intelfb driver.  I
have a notebook with an Intel Mobile GM965/GL960 Integrated Graphics
Controller and with the attached patch the framebuffer comes up.  I have
tested it a bit with DirectFB to make sure it is working stable.

I also have an Intel Mobile GM945 and I compared the results, the programming
interface of the 9xx series from Intel is mostly the same, so I think the
patch should add all the functionality which the 945GM has.

Signed-off-by: Maik Broemme <mbroemme@plusserver.de>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Antonino Daplas <adaplas@pol.net>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: Krzysztof Halasa <khc@pm.waw.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:41 -07:00
Jaya Kumar 03c33a4f00 fbdev: platforming metronomefb and am200epd
This patch splits metronomefb into the platform independent metronomefb and
the platform dependent am200epd.

Signed-off-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
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>
2008-04-28 08:58:41 -07:00
York Sun 9b53a9e28a fbdev: powerpc: driver for Freescale 8610 and 5121 DIU
The following features are supported:
plane 0 works as a regular frame buffer, can be accessed by /dev/fb0
plane 1 has two AOIs (area of interest), can be accessed by /dev/fb1 and /dev/fb2
plane 2 has two AOIs, can be accessed by /dev/fb3 and /dev/fb4
Special ioctls support AOIs

All /dev/fb* can be used as regular frame buffer devices, except hardware
change can only be made through /dev/fb0.  Changing pixel clock has no effect
on other fbs.

Limitation of usage of AOIs:
AOIs on the same plane can not be horizonally overlapped
AOIs have horizonal order, i.e. AOI0 should be always on top of AOI1
AOIs can not beyond phisical display area. Application should check AOI geometry
before changing physical resolution on /dev/fb0

required command line parameters to preallocate memory for frame buffer diufb.

optional command line parameters to set modes and monitor
video=fslfb:[resolution][,bpp][,monitor]
Syntax:

Resolution
xres x yres-bpp@refresh_rate, the -bpp and @refresh_rate are optional
eg, 1024x768, 1280x1024, 1280x1024-32, 1280x1024@60, 1280x1024-32@60, 1280x480-32@60

Bpp
bpp=32, bpp=24, or bpp=16

Monitor
monitor=0, monitor=1, monitor=2
0 is DVI
1 is Single link LVDS
2 is Double link LVDS

Note: switching monitor is a board feather, not DIU feather. MPC8610HPCD has three
monitor ports to swtich to. MPC5121ADS doesn't have additional monitor port. So switching
monirot port for MPC5121ADS has no effect.

If compiled as a module, it takes pamameters mode, bpp, monitor with the same syntax above.

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Timur Tabi <timur@freescale.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:40 -07:00
Andres Salomon 564820d42a lxfb: disable suspend VT switch by default
By default disable VT switch, but allow it to be overridden via the
'vt_switch' module arg.

Signed-off-by: Andres Salomon <dilinger@debian.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:39 -07:00