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Merge commit 'v2.6.29-rc1' into perfcounters/core

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Conflicts:
	include/linux/kernel_stat.h
This commit is contained in:
Ingo Molnar 2009-01-11 02:42:53 +01:00
commit 506c10f26c
6192 changed files with 842449 additions and 152253 deletions
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1
.mailmap
View File

@ -32,6 +32,7 @@ Christoph Hellwig <hch@lst.de>
Corey Minyard <minyard@acm.org>
David Brownell <david-b@pacbell.net>
David Woodhouse <dwmw2@shinybook.infradead.org>
Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Domen Puncer <domen@coderock.org>
Douglas Gilbert <dougg@torque.net>
Ed L. Cashin <ecashin@coraid.com>

27
CREDITS
View File

@ -369,10 +369,10 @@ P: 1024/8462A731 4C 55 86 34 44 59 A7 99 2B 97 88 4A 88 9A 0D 97
D: sun4 port, Sparc hacker
N: Hugh Blemings
E: hugh@misc.nu
W: http://misc.nu/hugh/
D: Author and maintainer of the Keyspan USB to Serial drivers
S: Po Box 234
E: hugh@blemings.org
W: http://blemings.org/hugh
D: Original author of the Keyspan USB to serial drivers, random PowerPC hacker
S: PO Box 234
S: Belconnen ACT 2616
S: Australia
@ -464,6 +464,11 @@ S: 1200 Goldenrod Dr.
S: Nampa, Idaho 83686
S: USA
N: Dirk J. Brandewie
E: dirk.j.brandewie@intel.com
E: linux-wimax@intel.com
D: Intel Wireless WiMAX Connection 2400 SDIO driver
N: Derrick J. Brashear
E: shadow@dementia.org
W: http://www.dementia.org/~shadow
@ -1681,7 +1686,7 @@ E: ajoshi@shell.unixbox.com
D: fbdev hacking
N: Jesper Juhl
E: jesper.juhl@gmail.com
E: jj@chaosbits.net
D: Various fixes, cleanups and minor features all over the tree.
D: Wrote initial version of the hdaps driver (since passed on to others).
S: Lemnosvej 1, 3.tv
@ -2119,6 +2124,11 @@ N: H.J. Lu
E: hjl@gnu.ai.mit.edu
D: GCC + libraries hacker
N: Yanir Lubetkin
E: yanirx.lubatkin@intel.com
E: linux-wimax@intel.com
D: Intel Wireless WiMAX Connection 2400 driver
N: Michal Ludvig
E: michal@logix.cz
E: michal.ludvig@asterisk.co.nz
@ -2693,6 +2703,13 @@ S: RR #5, 497 Pole Line Road
S: Thunder Bay, Ontario
S: CANADA P7C 5M9
N: Inaky Perez-Gonzalez
E: inaky.perez-gonzalez@intel.com
E: linux-wimax@intel.com
E: inakypg@yahoo.com
D: WiMAX stack
D: Intel Wireless WiMAX Connection 2400 driver
N: Yuri Per
E: yuri@pts.mipt.ru
D: Some smbfs fixes

136
Documentation/ABI/testing/sysfs-class-regulator
View File

@ -3,8 +3,9 @@ Date: April 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
state. This holds the regulator output state.
Some regulator directories will contain a field called
state. This reports the regulator enable status, for
regulators which can report that value.
This will be one of the following strings:
@ -18,7 +19,8 @@ Description:
'disabled' means the regulator output is OFF and is not
supplying power to the system..
'unknown' means software cannot determine the state.
'unknown' means software cannot determine the state, or
the reported state is invalid.
NOTE: this field can be used in conjunction with microvolts
and microamps to determine regulator output levels.
@ -53,9 +55,10 @@ Date: April 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
microvolts. This holds the regulator output voltage setting
measured in microvolts (i.e. E-6 Volts).
measured in microvolts (i.e. E-6 Volts), for regulators
which can report that voltage.
NOTE: This value should not be used to determine the regulator
output voltage level as this value is the same regardless of
@ -67,9 +70,10 @@ Date: April 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
microamps. This holds the regulator output current limit
setting measured in microamps (i.e. E-6 Amps).
setting measured in microamps (i.e. E-6 Amps), for regulators
which can report that current.
NOTE: This value should not be used to determine the regulator
output current level as this value is the same regardless of
@ -81,8 +85,9 @@ Date: April 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
opmode. This holds the regulator operating mode setting.
Some regulator directories will contain a field called
opmode. This holds the current regulator operating mode,
for regulators which can report it.
The opmode value can be one of the following strings:
@ -92,7 +97,7 @@ Description:
'standby'
'unknown'
The modes are described in include/linux/regulator/regulator.h
The modes are described in include/linux/regulator/consumer.h
NOTE: This value should not be used to determine the regulator
output operating mode as this value is the same regardless of
@ -104,9 +109,10 @@ Date: April 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
min_microvolts. This holds the minimum safe working regulator
output voltage setting for this domain measured in microvolts.
output voltage setting for this domain measured in microvolts,
for regulators which support voltage constraints.
NOTE: this will return the string 'constraint not defined' if
the power domain has no min microvolts constraint defined by
@ -118,9 +124,10 @@ Date: April 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
max_microvolts. This holds the maximum safe working regulator
output voltage setting for this domain measured in microvolts.
output voltage setting for this domain measured in microvolts,
for regulators which support voltage constraints.
NOTE: this will return the string 'constraint not defined' if
the power domain has no max microvolts constraint defined by
@ -132,10 +139,10 @@ Date: April 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
min_microamps. This holds the minimum safe working regulator
output current limit setting for this domain measured in
microamps.
microamps, for regulators which support current constraints.
NOTE: this will return the string 'constraint not defined' if
the power domain has no min microamps constraint defined by
@ -147,10 +154,10 @@ Date: April 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
max_microamps. This holds the maximum safe working regulator
output current limit setting for this domain measured in
microamps.
microamps, for regulators which support current constraints.
NOTE: this will return the string 'constraint not defined' if
the power domain has no max microamps constraint defined by
@ -185,7 +192,7 @@ Date: April 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
requested_microamps. This holds the total requested load
current in microamps for this regulator from all its consumer
devices.
@ -204,125 +211,102 @@ Date: May 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
suspend_mem_microvolts. This holds the regulator output
voltage setting for this domain measured in microvolts when
the system is suspended to memory.
NOTE: this will return the string 'not defined' if
the power domain has no suspend to memory voltage defined by
platform code.
the system is suspended to memory, for voltage regulators
implementing suspend voltage configuration constraints.
What: /sys/class/regulator/.../suspend_disk_microvolts
Date: May 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
suspend_disk_microvolts. This holds the regulator output
voltage setting for this domain measured in microvolts when
the system is suspended to disk.
NOTE: this will return the string 'not defined' if
the power domain has no suspend to disk voltage defined by
platform code.
the system is suspended to disk, for voltage regulators
implementing suspend voltage configuration constraints.
What: /sys/class/regulator/.../suspend_standby_microvolts
Date: May 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
suspend_standby_microvolts. This holds the regulator output
voltage setting for this domain measured in microvolts when
the system is suspended to standby.
NOTE: this will return the string 'not defined' if
the power domain has no suspend to standby voltage defined by
platform code.
the system is suspended to standby, for voltage regulators
implementing suspend voltage configuration constraints.
What: /sys/class/regulator/.../suspend_mem_mode
Date: May 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
suspend_mem_mode. This holds the regulator operating mode
setting for this domain when the system is suspended to
memory.
NOTE: this will return the string 'not defined' if
the power domain has no suspend to memory mode defined by
platform code.
memory, for regulators implementing suspend mode
configuration constraints.
What: /sys/class/regulator/.../suspend_disk_mode
Date: May 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
suspend_disk_mode. This holds the regulator operating mode
setting for this domain when the system is suspended to disk.
NOTE: this will return the string 'not defined' if
the power domain has no suspend to disk mode defined by
platform code.
setting for this domain when the system is suspended to disk,
for regulators implementing suspend mode configuration
constraints.
What: /sys/class/regulator/.../suspend_standby_mode
Date: May 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
suspend_standby_mode. This holds the regulator operating mode
setting for this domain when the system is suspended to
standby.
NOTE: this will return the string 'not defined' if
the power domain has no suspend to standby mode defined by
platform code.
standby, for regulators implementing suspend mode
configuration constraints.
What: /sys/class/regulator/.../suspend_mem_state
Date: May 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
suspend_mem_state. This holds the regulator operating state
when suspended to memory.
when suspended to memory, for regulators implementing suspend
configuration constraints.
This will be one of the following strings:
'enabled'
'disabled'
'not defined'
This will be one of the same strings reported by
the "state" attribute.
What: /sys/class/regulator/.../suspend_disk_state
Date: May 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
suspend_disk_state. This holds the regulator operating state
when suspended to disk.
when suspended to disk, for regulators implementing
suspend configuration constraints.
This will be one of the following strings:
'enabled'
'disabled'
'not defined'
This will be one of the same strings reported by
the "state" attribute.
What: /sys/class/regulator/.../suspend_standby_state
Date: May 2008
KernelVersion: 2.6.26
Contact: Liam Girdwood <lrg@slimlogic.co.uk>
Description:
Each regulator directory will contain a field called
Some regulator directories will contain a field called
suspend_standby_state. This holds the regulator operating
state when suspended to standby.
state when suspended to standby, for regulators implementing
suspend configuration constraints.
This will be one of the following strings:
'enabled'
'disabled'
'not defined'
This will be one of the same strings reported by
the "state" attribute.

14
Documentation/ABI/testing/sysfs-class-uwb_rc
View File

@ -32,14 +32,16 @@ Contact: linux-usb@vger.kernel.org
Description:
Write:
<channel> [<bpst offset>]
<channel>
to start beaconing on a specific channel, or stop
beaconing if <channel> is -1. Valid channels depends
on the radio controller's supported band groups.
to force a specific channel to be used when beaconing,
or, if <channel> is -1, to prohibit beaconing. If
<channel> is 0, then the default channel selection
algorithm will be used. Valid channels depends on the
radio controller's supported band groups.
<bpst offset> may be used to try and join a specific
beacon group if more than one was found during a scan.
Reading returns the currently active channel, or -1 if
the radio controller is not beaconing.
What: /sys/class/uwb_rc/uwbN/scan
Date: July 2008

53
Documentation/ABI/testing/sysfs-devices-memory
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@ -6,7 +6,6 @@ Description:
internal state of the kernel memory blocks. Files could be
added or removed dynamically to represent hot-add/remove
operations.
Users: hotplug memory add/remove tools
https://w3.opensource.ibm.com/projects/powerpc-utils/
@ -19,6 +18,56 @@ Description:
This is useful for a user-level agent to determine
identify removable sections of the memory before attempting
potentially expensive hot-remove memory operation
Users: hotplug memory remove tools
https://w3.opensource.ibm.com/projects/powerpc-utils/
What: /sys/devices/system/memory/memoryX/phys_device
Date: September 2008
Contact: Badari Pulavarty <pbadari@us.ibm.com>
Description:
The file /sys/devices/system/memory/memoryX/phys_device
is read-only and is designed to show the name of physical
memory device. Implementation is currently incomplete.
What: /sys/devices/system/memory/memoryX/phys_index
Date: September 2008
Contact: Badari Pulavarty <pbadari@us.ibm.com>
Description:
The file /sys/devices/system/memory/memoryX/phys_index
is read-only and contains the section ID in hexadecimal
which is equivalent to decimal X contained in the
memory section directory name.
What: /sys/devices/system/memory/memoryX/state
Date: September 2008
Contact: Badari Pulavarty <pbadari@us.ibm.com>
Description:
The file /sys/devices/system/memory/memoryX/state
is read-write. When read, it's contents show the
online/offline state of the memory section. When written,
root can toggle the the online/offline state of a removable
memory section (see removable file description above)
using the following commands.
# echo online > /sys/devices/system/memory/memoryX/state
# echo offline > /sys/devices/system/memory/memoryX/state
For example, if /sys/devices/system/memory/memory22/removable
contains a value of 1 and
/sys/devices/system/memory/memory22/state contains the
string "online" the following command can be executed by
by root to offline that section.
# echo offline > /sys/devices/system/memory/memory22/state
Users: hotplug memory remove tools
https://w3.opensource.ibm.com/projects/powerpc-utils/
What: /sys/devices/system/node/nodeX/memoryY
Date: September 2008
Contact: Gary Hade <garyhade@us.ibm.com>
Description:
When CONFIG_NUMA is enabled
/sys/devices/system/node/nodeX/memoryY is a symbolic link that
points to the corresponding /sys/devices/system/memory/memoryY
memory section directory. For example, the following symbolic
link is created for memory section 9 on node0.
/sys/devices/system/node/node0/memory9 -> ../../memory/memory9

2
Documentation/DMA-mapping.txt
View File

@ -26,7 +26,7 @@ mapped only for the time they are actually used and unmapped after the DMA
transfer.
The following API will work of course even on platforms where no such
hardware exists, see e.g. include/asm-i386/pci.h for how it is implemented on
hardware exists, see e.g. arch/x86/include/asm/pci.h for how it is implemented on
top of the virt_to_bus interface.
First of all, you should make sure

2
Documentation/DocBook/Makefile
View File

@ -12,7 +12,7 @@ DOCBOOKS := z8530book.xml mcabook.xml \
kernel-api.xml filesystems.xml lsm.xml usb.xml kgdb.xml \
gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \
genericirq.xml s390-drivers.xml uio-howto.xml scsi.xml \
mac80211.xml debugobjects.xml sh.xml
mac80211.xml debugobjects.xml sh.xml regulator.xml
###
# The build process is as follows (targets):

8
Documentation/DocBook/networking.tmpl
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@ -74,6 +74,14 @@
!Enet/sunrpc/rpcb_clnt.c
!Enet/sunrpc/clnt.c
</sect1>
<sect1><title>WiMAX</title>
!Enet/wimax/op-msg.c
!Enet/wimax/op-reset.c
!Enet/wimax/op-rfkill.c
!Enet/wimax/stack.c
!Iinclude/net/wimax.h
!Iinclude/linux/wimax.h
</sect1>
</chapter>
<chapter id="netdev">

304
Documentation/DocBook/regulator.tmpl Normal file
View File

@ -0,0 +1,304 @@
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
<book id="regulator-api">
<bookinfo>
<title>Voltage and current regulator API</title>
<authorgroup>
<author>
<firstname>Liam</firstname>
<surname>Girdwood</surname>
<affiliation>
<address>
<email>lrg@slimlogic.co.uk</email>
</address>
</affiliation>
</author>
<author>
<firstname>Mark</firstname>
<surname>Brown</surname>
<affiliation>
<orgname>Wolfson Microelectronics</orgname>
<address>
<email>broonie@opensource.wolfsonmicro.com</email>
</address>
</affiliation>
</author>
</authorgroup>
<copyright>
<year>2007-2008</year>
<holder>Wolfson Microelectronics</holder>
</copyright>
<copyright>
<year>2008</year>
<holder>Liam Girdwood</holder>
</copyright>
<legalnotice>
<para>
This documentation is free software; you can redistribute
it and/or modify it under the terms of the GNU General Public
License version 2 as published by the Free Software Foundation.
</para>
<para>
This program is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
</para>
<para>
You should have received a copy of the GNU General Public
License along with this program; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
MA 02111-1307 USA
</para>
<para>
For more details see the file COPYING in the source
distribution of Linux.
</para>
</legalnotice>
</bookinfo>
<toc></toc>
<chapter id="intro">
<title>Introduction</title>
<para>
This framework is designed to provide a standard kernel
interface to control voltage and current regulators.
</para>
<para>
The intention is to allow systems to dynamically control
regulator power output in order to save power and prolong
battery life. This applies to both voltage regulators (where
voltage output is controllable) and current sinks (where current
limit is controllable).
</para>
<para>
Note that additional (and currently more complete) documentation
is available in the Linux kernel source under
<filename>Documentation/power/regulator</filename>.
</para>
<sect1 id="glossary">
<title>Glossary</title>
<para>
The regulator API uses a number of terms which may not be
familiar:
</para>
<glossary>
<glossentry>
<glossterm>Regulator</glossterm>
<glossdef>
<para>
Electronic device that supplies power to other devices. Most
regulators can enable and disable their output and some can also
control their output voltage or current.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>Consumer</glossterm>
<glossdef>
<para>
Electronic device which consumes power provided by a regulator.
These may either be static, requiring only a fixed supply, or
dynamic, requiring active management of the regulator at
runtime.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>Power Domain</glossterm>
<glossdef>
<para>
The electronic circuit supplied by a given regulator, including
the regulator and all consumer devices. The configuration of
the regulator is shared between all the components in the
circuit.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>Power Management Integrated Circuit</glossterm>
<acronym>PMIC</acronym>
<glossdef>
<para>
An IC which contains numerous regulators and often also other
subsystems. In an embedded system the primary PMIC is often
equivalent to a combination of the PSU and southbridge in a
desktop system.
</para>
</glossdef>
</glossentry>
</glossary>
</sect1>
</chapter>
<chapter id="consumer">
<title>Consumer driver interface</title>
<para>
This offers a similar API to the kernel clock framework.
Consumer drivers use <link
linkend='API-regulator-get'>get</link> and <link
linkend='API-regulator-put'>put</link> operations to acquire and
release regulators. Functions are
provided to <link linkend='API-regulator-enable'>enable</link>
and <link linkend='API-regulator-disable'>disable</link> the
reguator and to get and set the runtime parameters of the
regulator.
</para>
<para>
When requesting regulators consumers use symbolic names for their
supplies, such as "Vcc", which are mapped into actual regulator
devices by the machine interface.
</para>
<para>
A stub version of this API is provided when the regulator
framework is not in use in order to minimise the need to use
ifdefs.
</para>
<sect1 id="consumer-enable">
<title>Enabling and disabling</title>
<para>
The regulator API provides reference counted enabling and
disabling of regulators. Consumer devices use the <function><link
linkend='API-regulator-enable'>regulator_enable</link></function>
and <function><link
linkend='API-regulator-disable'>regulator_disable</link>
</function> functions to enable and disable regulators. Calls
to the two functions must be balanced.
</para>
<para>
Note that since multiple consumers may be using a regulator and
machine constraints may not allow the regulator to be disabled
there is no guarantee that calling
<function>regulator_disable</function> will actually cause the
supply provided by the regulator to be disabled. Consumer
drivers should assume that the regulator may be enabled at all
times.
</para>
</sect1>
<sect1 id="consumer-config">
<title>Configuration</title>
<para>
Some consumer devices may need to be able to dynamically
configure their supplies. For example, MMC drivers may need to
select the correct operating voltage for their cards. This may
be done while the regulator is enabled or disabled.
</para>
<para>
The <function><link
linkend='API-regulator-set-voltage'>regulator_set_voltage</link>
</function> and <function><link
linkend='API-regulator-set-current-limit'
>regulator_set_current_limit</link>
</function> functions provide the primary interface for this.
Both take ranges of voltages and currents, supporting drivers
that do not require a specific value (eg, CPU frequency scaling
normally permits the CPU to use a wider range of supply
voltages at lower frequencies but does not require that the
supply voltage be lowered). Where an exact value is required
both minimum and maximum values should be identical.
</para>
</sect1>
<sect1 id="consumer-callback">
<title>Callbacks</title>
<para>
Callbacks may also be <link
linkend='API-regulator-register-notifier'>registered</link>
for events such as regulation failures.
</para>
</sect1>
</chapter>
<chapter id="driver">
<title>Regulator driver interface</title>
<para>
Drivers for regulator chips <link
linkend='API-regulator-register'>register</link> the regulators
with the regulator core, providing operations structures to the
core. A <link
linkend='API-regulator-notifier-call-chain'>notifier</link> interface
allows error conditions to be reported to the core.
</para>
<para>
Registration should be triggered by explicit setup done by the
platform, supplying a <link
linkend='API-struct-regulator-init-data'>struct
regulator_init_data</link> for the regulator containing
<link linkend='machine-constraint'>constraint</link> and
<link linkend='machine-supply'>supply</link> information.
</para>
</chapter>
<chapter id="machine">
<title>Machine interface</title>
<para>
This interface provides a way to define how regulators are
connected to consumers on a given system and what the valid
operating parameters are for the system.
</para>
<sect1 id="machine-supply">
<title>Supplies</title>
<para>
Regulator supplies are specified using <link
linkend='API-struct-regulator-consumer-supply'>struct
regulator_consumer_supply</link>. This is done at
<link linkend='driver'>driver registration
time</link> as part of the machine constraints.
</para>
</sect1>
<sect1 id="machine-constraint">
<title>Constraints</title>
<para>
As well as definining the connections the machine interface
also provides constraints definining the operations that
clients are allowed to perform and the parameters that may be
set. This is required since generally regulator devices will
offer more flexibility than it is safe to use on a given
system, for example supporting higher supply voltages than the
consumers are rated for.
</para>
<para>
This is done at <link linkend='driver'>driver
registration time</link> by providing a <link
linkend='API-struct-regulation-constraints'>struct
regulation_constraints</link>.
</para>
<para>
The constraints may also specify an initial configuration for the
regulator in the constraints, which is particularly useful for
use with static consumers.
</para>
</sect1>
</chapter>
<chapter id="api">
<title>API reference</title>
<para>
Due to limitations of the kernel documentation framework and the
existing layout of the source code the entire regulator API is
documented here.
</para>
!Iinclude/linux/regulator/consumer.h
!Iinclude/linux/regulator/machine.h
!Iinclude/linux/regulator/driver.h
!Edrivers/regulator/core.c
</chapter>
</book>

101
Documentation/DocBook/uio-howto.tmpl
View File

@ -41,6 +41,12 @@ GPL version 2.
</abstract>
<revhistory>
<revision>
<revnumber>0.6</revnumber>
<date>2008-12-05</date>
<authorinitials>hjk</authorinitials>
<revremark>Added description of portio sysfs attributes.</revremark>
</revision>
<revision>
<revnumber>0.5</revnumber>
<date>2008-05-22</date>
@ -318,6 +324,54 @@ interested in translating it, please email me
offset = N * getpagesize();
</programlisting>
<para>
Sometimes there is hardware with memory-like regions that can not be
mapped with the technique described here, but there are still ways to
access them from userspace. The most common example are x86 ioports.
On x86 systems, userspace can access these ioports using
<function>ioperm()</function>, <function>iopl()</function>,
<function>inb()</function>, <function>outb()</function>, and similar
functions.
</para>
<para>
Since these ioport regions can not be mapped, they will not appear under
<filename>/sys/class/uio/uioX/maps/</filename> like the normal memory
described above. Without information about the port regions a hardware
has to offer, it becomes difficult for the userspace part of the
driver to find out which ports belong to which UIO device.
</para>
<para>
To address this situation, the new directory
<filename>/sys/class/uio/uioX/portio/</filename> was added. It only
exists if the driver wants to pass information about one or more port
regions to userspace. If that is the case, subdirectories named
<filename>port0</filename>, <filename>port1</filename>, and so on,
will appear underneath
<filename>/sys/class/uio/uioX/portio/</filename>.
</para>
<para>
Each <filename>portX/</filename> directory contains three read-only
files that show start, size, and type of the port region:
</para>
<itemizedlist>
<listitem>
<para>
<filename>start</filename>: The first port of this region.
</para>
</listitem>
<listitem>
<para>
<filename>size</filename>: The number of ports in this region.
</para>
</listitem>
<listitem>
<para>
<filename>porttype</filename>: A string describing the type of port.
</para>
</listitem>
</itemizedlist>
</sect1>
</chapter>
@ -339,12 +393,12 @@ offset = N * getpagesize();
<itemizedlist>
<listitem><para>
<varname>char *name</varname>: Required. The name of your driver as
<varname>const char *name</varname>: Required. The name of your driver as
it will appear in sysfs. I recommend using the name of your module for this.
</para></listitem>
<listitem><para>
<varname>char *version</varname>: Required. This string appears in
<varname>const char *version</varname>: Required. This string appears in
<filename>/sys/class/uio/uioX/version</filename>.
</para></listitem>
@ -355,6 +409,13 @@ mapping you need to fill one of the <varname>uio_mem</varname> structures.
See the description below for details.
</para></listitem>
<listitem><para>
<varname>struct uio_port port[ MAX_UIO_PORTS_REGIONS ]</varname>: Required
if you want to pass information about ioports to userspace. For each port
region you need to fill one of the <varname>uio_port</varname> structures.
See the description below for details.
</para></listitem>
<listitem><para>
<varname>long irq</varname>: Required. If your hardware generates an
interrupt, it's your modules task to determine the irq number during
@ -448,6 +509,42 @@ Please do not touch the <varname>kobj</varname> element of
<varname>struct uio_mem</varname>! It is used by the UIO framework
to set up sysfs files for this mapping. Simply leave it alone.
</para>
<para>
Sometimes, your device can have one or more port regions which can not be
mapped to userspace. But if there are other possibilities for userspace to
access these ports, it makes sense to make information about the ports
available in sysfs. For each region, you have to set up a
<varname>struct uio_port</varname> in the <varname>port[]</varname> array.
Here's a description of the fields of <varname>struct uio_port</varname>:
</para>
<itemizedlist>
<listitem><para>
<varname>char *porttype</varname>: Required. Set this to one of the predefined
constants. Use <varname>UIO_PORT_X86</varname> for the ioports found in x86
architectures.
</para></listitem>
<listitem><para>
<varname>unsigned long start</varname>: Required if the port region is used.
Fill in the number of the first port of this region.
</para></listitem>
<listitem><para>
<varname>unsigned long size</varname>: Fill in the number of ports in this
region. If <varname>size</varname> is zero, the region is considered unused.
Note that you <emphasis>must</emphasis> initialize <varname>size</varname>
with zero for all unused regions.
</para></listitem>
</itemizedlist>
<para>
Please do not touch the <varname>portio</varname> element of
<varname>struct uio_port</varname>! It is used internally by the UIO
framework to set up sysfs files for this region. Simply leave it alone.
</para>
</sect1>
<sect1 id="adding_irq_handler">

3
Documentation/PCI/pci.txt
View File

@ -294,7 +294,8 @@ NOTE: pci_enable_device() can fail! Check the return value.
pci_set_master() will enable DMA by setting the bus master bit
in the PCI_COMMAND register. It also fixes the latency timer value if
it's set to something bogus by the BIOS.
it's set to something bogus by the BIOS. pci_clear_master() will
disable DMA by clearing the bus master bit.
If the PCI device can use the PCI Memory-Write-Invalidate transaction,
call pci_set_mwi(). This enables the PCI_COMMAND bit for Mem-Wr-Inval

4
Documentation/RCU/00-INDEX
View File

@ -12,10 +12,14 @@ rcuref.txt
- Reference-count design for elements of lists/arrays protected by RCU
rcu.txt
- RCU Concepts
rcubarrier.txt
- Unloading modules that use RCU callbacks
RTFP.txt
- List of RCU papers (bibliography) going back to 1980.
torture.txt
- RCU Torture Test Operation (CONFIG_RCU_TORTURE_TEST)
trace.txt
- CONFIG_RCU_TRACE debugfs files and formats
UP.txt
- RCU on Uniprocessor Systems
whatisRCU.txt

304
Documentation/RCU/rcubarrier.txt Normal file
View File

@ -0,0 +1,304 @@
RCU and Unloadable Modules
[Originally published in LWN Jan. 14, 2007: http://lwn.net/Articles/217484/]
RCU (read-copy update) is a synchronization mechanism that can be thought
of as a replacement for read-writer locking (among other things), but with
very low-overhead readers that are immune to deadlock, priority inversion,
and unbounded latency. RCU read-side critical sections are delimited
by rcu_read_lock() and rcu_read_unlock(), which, in non-CONFIG_PREEMPT
kernels, generate no code whatsoever.
This means that RCU writers are unaware of the presence of concurrent
readers, so that RCU updates to shared data must be undertaken quite
carefully, leaving an old version of the data structure in place until all
pre-existing readers have finished. These old versions are needed because
such readers might hold a reference to them. RCU updates can therefore be
rather expensive, and RCU is thus best suited for read-mostly situations.
How can an RCU writer possibly determine when all readers are finished,
given that readers might well leave absolutely no trace of their
presence? There is a synchronize_rcu() primitive that blocks until all
pre-existing readers have completed. An updater wishing to delete an
element p from a linked list might do the following, while holding an
appropriate lock, of course:
list_del_rcu(p);
synchronize_rcu();
kfree(p);
But the above code cannot be used in IRQ context -- the call_rcu()
primitive must be used instead. This primitive takes a pointer to an
rcu_head struct placed within the RCU-protected data structure and
another pointer to a function that may be invoked later to free that
structure. Code to delete an element p from the linked list from IRQ
context might then be as follows:
list_del_rcu(p);
call_rcu(&p->rcu, p_callback);
Since call_rcu() never blocks, this code can safely be used from within
IRQ context. The function p_callback() might be defined as follows:
static void p_callback(struct rcu_head *rp)
{
struct pstruct *p = container_of(rp, struct pstruct, rcu);
kfree(p);
}
Unloading Modules That Use call_rcu()
But what if p_callback is defined in an unloadable module?
If we unload the module while some RCU callbacks are pending,
the CPUs executing these callbacks are going to be severely
disappointed when they are later invoked, as fancifully depicted at
http://lwn.net/images/ns/kernel/rcu-drop.jpg.
We could try placing a synchronize_rcu() in the module-exit code path,
but this is not sufficient. Although synchronize_rcu() does wait for a
grace period to elapse, it does not wait for the callbacks to complete.
One might be tempted to try several back-to-back synchronize_rcu()
calls, but this is still not guaranteed to work. If there is a very
heavy RCU-callback load, then some of the callbacks might be deferred
in order to allow other processing to proceed. Such deferral is required
in realtime kernels in order to avoid excessive scheduling latencies.
rcu_barrier()
We instead need the rcu_barrier() primitive. This primitive is similar
to synchronize_rcu(), but instead of waiting solely for a grace
period to elapse, it also waits for all outstanding RCU callbacks to
complete. Pseudo-code using rcu_barrier() is as follows:
1. Prevent any new RCU callbacks from being posted.
2. Execute rcu_barrier().
3. Allow the module to be unloaded.
Quick Quiz #1: Why is there no srcu_barrier()?
The rcutorture module makes use of rcu_barrier in its exit function
as follows:
1 static void
2 rcu_torture_cleanup(void)
3 {
4 int i;
5
6 fullstop = 1;
7 if (shuffler_task != NULL) {
8 VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task");
9 kthread_stop(shuffler_task);
10 }
11 shuffler_task = NULL;
12
13 if (writer_task != NULL) {
14 VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task");
15 kthread_stop(writer_task);
16 }
17 writer_task = NULL;
18
19 if (reader_tasks != NULL) {
20 for (i = 0; i < nrealreaders; i++) {
21 if (reader_tasks[i] != NULL) {
22 VERBOSE_PRINTK_STRING(
23 "Stopping rcu_torture_reader task");
24 kthread_stop(reader_tasks[i]);
25 }
26 reader_tasks[i] = NULL;
27 }
28 kfree(reader_tasks);
29 reader_tasks = NULL;
30 }
31 rcu_torture_current = NULL;
32
33 if (fakewriter_tasks != NULL) {
34 for (i = 0; i < nfakewriters; i++) {
35 if (fakewriter_tasks[i] != NULL) {
36 VERBOSE_PRINTK_STRING(
37 "Stopping rcu_torture_fakewriter task");
38 kthread_stop(fakewriter_tasks[i]);
39 }
40 fakewriter_tasks[i] = NULL;
41 }
42 kfree(fakewriter_tasks);
43 fakewriter_tasks = NULL;
44 }
45
46 if (stats_task != NULL) {
47 VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task");
48 kthread_stop(stats_task);
49 }
50 stats_task = NULL;
51
52 /* Wait for all RCU callbacks to fire. */
53 rcu_barrier();
54
55 rcu_torture_stats_print(); /* -After- the stats thread is stopped! */
56
57 if (cur_ops->cleanup != NULL)
58 cur_ops->cleanup();
59 if (atomic_read(&n_rcu_torture_error))
60 rcu_torture_print_module_parms("End of test: FAILURE");
61 else
62 rcu_torture_print_module_parms("End of test: SUCCESS");
63 }
Line 6 sets a global variable that prevents any RCU callbacks from
re-posting themselves. This will not be necessary in most cases, since
RCU callbacks rarely include calls to call_rcu(). However, the rcutorture
module is an exception to this rule, and therefore needs to set this
global variable.
Lines 7-50 stop all the kernel tasks associated with the rcutorture
module. Therefore, once execution reaches line 53, no more rcutorture
RCU callbacks will be posted. The rcu_barrier() call on line 53 waits
for any pre-existing callbacks to complete.
Then lines 55-62 print status and do operation-specific cleanup, and
then return, permitting the module-unload operation to be completed.
Quick Quiz #2: Is there any other situation where rcu_barrier() might
be required?
Your module might have additional complications. For example, if your
module invokes call_rcu() from timers, you will need to first cancel all
the timers, and only then invoke rcu_barrier() to wait for any remaining
RCU callbacks to complete.
Implementing rcu_barrier()
Dipankar Sarma's implementation of rcu_barrier() makes use of the fact
that RCU callbacks are never reordered once queued on one of the per-CPU
queues. His implementation queues an RCU callback on each of the per-CPU
callback queues, and then waits until they have all started executing, at
which point, all earlier RCU callbacks are guaranteed to have completed.
The original code for rcu_barrier() was as follows:
1 void rcu_barrier(void)
2 {
3 BUG_ON(in_interrupt());
4 /* Take cpucontrol mutex to protect against CPU hotplug */
5 mutex_lock(&rcu_barrier_mutex);
6 init_completion(&rcu_barrier_completion);
7 atomic_set(&rcu_barrier_cpu_count, 0);
8 on_each_cpu(rcu_barrier_func, NULL, 0, 1);
9 wait_for_completion(&rcu_barrier_completion);
10 mutex_unlock(&rcu_barrier_mutex);
11 }
Line 3 verifies that the caller is in process context, and lines 5 and 10
use rcu_barrier_mutex to ensure that only one rcu_barrier() is using the
global completion and counters at a time, which are initialized on lines
6 and 7. Line 8 causes each CPU to invoke rcu_barrier_func(), which is
shown below. Note that the final "1" in on_each_cpu()'s argument list
ensures that all the calls to rcu_barrier_func() will have completed
before on_each_cpu() returns. Line 9 then waits for the completion.
This code was rewritten in 2008 to support rcu_barrier_bh() and
rcu_barrier_sched() in addition to the original rcu_barrier().
The rcu_barrier_func() runs on each CPU, where it invokes call_rcu()
to post an RCU callback, as follows:
1 static void rcu_barrier_func(void *notused)
2 {
3 int cpu = smp_processor_id();
4 struct rcu_data *rdp = &per_cpu(rcu_data, cpu);
5 struct rcu_head *head;
6
7 head = &rdp->barrier;
8 atomic_inc(&rcu_barrier_cpu_count);
9 call_rcu(head, rcu_barrier_callback);
10 }
Lines 3 and 4 locate RCU's internal per-CPU rcu_data structure,
which contains the struct rcu_head that needed for the later call to
call_rcu(). Line 7 picks up a pointer to this struct rcu_head, and line
8 increments a global counter. This counter will later be decremented
by the callback. Line 9 then registers the rcu_barrier_callback() on
the current CPU's queue.
The rcu_barrier_callback() function simply atomically decrements the
rcu_barrier_cpu_count variable and finalizes the completion when it
reaches zero, as follows:
1 static void rcu_barrier_callback(struct rcu_head *notused)
2 {
3 if (atomic_dec_and_test(&rcu_barrier_cpu_count))
4 complete(&rcu_barrier_completion);
5 }
Quick Quiz #3: What happens if CPU 0's rcu_barrier_func() executes
immediately (thus incrementing rcu_barrier_cpu_count to the
value one), but the other CPU's rcu_barrier_func() invocations
are delayed for a full grace period? Couldn't this result in
rcu_barrier() returning prematurely?
rcu_barrier() Summary
The rcu_barrier() primitive has seen relatively little use, since most
code using RCU is in the core kernel rather than in modules. However, if
you are using RCU from an unloadable module, you need to use rcu_barrier()
so that your module may be safely unloaded.
Answers to Quick Quizzes
Quick Quiz #1: Why is there no srcu_barrier()?
Answer: Since there is no call_srcu(), there can be no outstanding SRCU
callbacks. Therefore, there is no need to wait for them.
Quick Quiz #2: Is there any other situation where rcu_barrier() might
be required?
Answer: Interestingly enough, rcu_barrier() was not originally
implemented for module unloading. Nikita Danilov was using
RCU in a filesystem, which resulted in a similar situation at
filesystem-unmount time. Dipankar Sarma coded up rcu_barrier()
in response, so that Nikita could invoke it during the
filesystem-unmount process.
Much later, yours truly hit the RCU module-unload problem when
implementing rcutorture, and found that rcu_barrier() solves
this problem as well.
Quick Quiz #3: What happens if CPU 0's rcu_barrier_func() executes
immediately (thus incrementing rcu_barrier_cpu_count to the
value one), but the other CPU's rcu_barrier_func() invocations
are delayed for a full grace period? Couldn't this result in
rcu_barrier() returning prematurely?
Answer: This cannot happen. The reason is that on_each_cpu() has its last
argument, the wait flag, set to "1". This flag is passed through
to smp_call_function() and further to smp_call_function_on_cpu(),
causing this latter to spin until the cross-CPU invocation of
rcu_barrier_func() has completed. This by itself would prevent
a grace period from completing on non-CONFIG_PREEMPT kernels,
since each CPU must undergo a context switch (or other quiescent
state) before the grace period can complete. However, this is
of no use in CONFIG_PREEMPT kernels.
Therefore, on_each_cpu() disables preemption across its call
to smp_call_function() and also across the local call to
rcu_barrier_func(). This prevents the local CPU from context
switching, again preventing grace periods from completing. This
means that all CPUs have executed rcu_barrier_func() before
the first rcu_barrier_callback() can possibly execute, in turn
preventing rcu_barrier_cpu_count from prematurely reaching zero.
Currently, -rt implementations of RCU keep but a single global
queue for RCU callbacks, and thus do not suffer from this
problem. However, when the -rt RCU eventually does have per-CPU
callback queues, things will have to change. One simple change
is to add an rcu_read_lock() before line 8 of rcu_barrier()
and an rcu_read_unlock() after line 8 of this same function. If
you can think of a better change, please let me know!

413
Documentation/RCU/trace.txt Normal file
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@ -0,0 +1,413 @@
CONFIG_RCU_TRACE debugfs Files and Formats
The rcupreempt and rcutree implementations of RCU provide debugfs trace
output that summarizes counters and state. This information is useful for
debugging RCU itself, and can sometimes also help to debug abuses of RCU.
Note that the rcuclassic implementation of RCU does not provide debugfs
trace output.
The following sections describe the debugfs files and formats for
preemptable RCU (rcupreempt) and hierarchical RCU (rcutree).
Preemptable RCU debugfs Files and Formats
This implementation of RCU provides three debugfs files under the
top-level directory RCU: rcu/rcuctrs (which displays the per-CPU
counters used by preemptable RCU) rcu/rcugp (which displays grace-period
counters), and rcu/rcustats (which internal counters for debugging RCU).
The output of "cat rcu/rcuctrs" looks as follows:
CPU last cur F M
0 5 -5 0 0
1 -1 0 0 0
2 0 1 0 0
3 0 1 0 0
4 0 1 0 0
5 0 1 0 0
6 0 2 0 0
7 0 -1 0 0
8 0 1 0 0
ggp = 26226, state = waitzero
The per-CPU fields are as follows:
o "CPU" gives the CPU number. Offline CPUs are not displayed.
o "last" gives the value of the counter that is being decremented
for the current grace period phase. In the example above,
the counters sum to 4, indicating that there are still four
RCU read-side critical sections still running that started
before the last counter flip.
o "cur" gives the value of the counter that is currently being
both incremented (by rcu_read_lock()) and decremented (by
rcu_read_unlock()). In the example above, the counters sum to
1, indicating that there is only one RCU read-side critical section
still running that started after the last counter flip.
o "F" indicates whether RCU is waiting for this CPU to acknowledge
a counter flip. In the above example, RCU is not waiting on any,
which is consistent with the state being "waitzero" rather than
"waitack".
o "M" indicates whether RCU is waiting for this CPU to execute a
memory barrier. In the above example, RCU is not waiting on any,
which is consistent with the state being "waitzero" rather than
"waitmb".
o "ggp" is the global grace-period counter.
o "state" is the RCU state, which can be one of the following:
o "idle": there is no grace period in progress.
o "waitack": RCU just incremented the global grace-period
counter, which has the effect of reversing the roles of
the "last" and "cur" counters above, and is waiting for
all the CPUs to acknowledge the flip. Once the flip has
been acknowledged, CPUs will no longer be incrementing
what are now the "last" counters, so that their sum will
decrease monotonically down to zero.
o "waitzero": RCU is waiting for the sum of the "last" counters
to decrease to zero.
o "waitmb": RCU is waiting for each CPU to execute a memory
barrier, which ensures that instructions from a given CPU's
last RCU read-side critical section cannot be reordered
with instructions following the memory-barrier instruction.
The output of "cat rcu/rcugp" looks as follows:
oldggp=48870 newggp=48873
Note that reading from this file provokes a synchronize_rcu(). The
"oldggp" value is that of "ggp" from rcu/rcuctrs above, taken before
executing the synchronize_rcu(), and the "newggp" value is also the
"ggp" value, but taken after the synchronize_rcu() command returns.
The output of "cat rcu/rcugp" looks as follows:
na=1337955 nl=40 wa=1337915 wl=44 da=1337871 dl=0 dr=1337871 di=1337871
1=50989 e1=6138 i1=49722 ie1=82 g1=49640 a1=315203 ae1=265563 a2=49640
z1=1401244 ze1=1351605 z2=49639 m1=5661253 me1=5611614 m2=49639
These are counters tracking internal preemptable-RCU events, however,
some of them may be useful for debugging algorithms using RCU. In
particular, the "nl", "wl", and "dl" values track the number of RCU
callbacks in various states. The fields are as follows:
o "na" is the total number of RCU callbacks that have been enqueued
since boot.
o "nl" is the number of RCU callbacks waiting for the previous
grace period to end so that they can start waiting on the next
grace period.
o "wa" is the total number of RCU callbacks that have started waiting
for a grace period since boot. "na" should be roughly equal to
"nl" plus "wa".
o "wl" is the number of RCU callbacks currently waiting for their
grace period to end.
o "da" is the total number of RCU callbacks whose grace periods
have completed since boot. "wa" should be roughly equal to
"wl" plus "da".
o "dr" is the total number of RCU callbacks that have been removed
from the list of callbacks ready to invoke. "dr" should be roughly
equal to "da".
o "di" is the total number of RCU callbacks that have been invoked
since boot. "di" should be roughly equal to "da", though some
early versions of preemptable RCU had a bug so that only the
last CPU's count of invocations was displayed, rather than the
sum of all CPU's counts.
o "1" is the number of calls to rcu_try_flip(). This should be
roughly equal to the sum of "e1", "i1", "a1", "z1", and "m1"
described below. In other words, the number of times that
the state machine is visited should be equal to the sum of the
number of times that each state is visited plus the number of
times that the state-machine lock acquisition failed.
o "e1" is the number of times that rcu_try_flip() was unable to
acquire the fliplock.
o "i1" is the number of calls to rcu_try_flip_idle().
o "ie1" is the number of times rcu_try_flip_idle() exited early
due to the calling CPU having no work for RCU.
o "g1" is the number of times that rcu_try_flip_idle() decided
to start a new grace period. "i1" should be roughly equal to
"ie1" plus "g1".
o "a1" is the number of calls to rcu_try_flip_waitack().
o "ae1" is the number of times that rcu_try_flip_waitack() found
that at least one CPU had not yet acknowledge the new grace period
(AKA "counter flip").
o "a2" is the number of time rcu_try_flip_waitack() found that
all CPUs had acknowledged. "a1" should be roughly equal to
"ae1" plus "a2". (This particular output was collected on
a 128-CPU machine, hence the smaller-than-usual fraction of
calls to rcu_try_flip_waitack() finding all CPUs having already
acknowledged.)
o "z1" is the number of calls to rcu_try_flip_waitzero().
o "ze1" is the number of times that rcu_try_flip_waitzero() found
that not all of the old RCU read-side critical sections had
completed.
o "z2" is the number of times that rcu_try_flip_waitzero() finds
the sum of the counters equal to zero, in other words, that
all of the old RCU read-side critical sections had completed.
The value of "z1" should be roughly equal to "ze1" plus
"z2".
o "m1" is the number of calls to rcu_try_flip_waitmb().
o "me1" is the number of times that rcu_try_flip_waitmb() finds
that at least one CPU has not yet executed a memory barrier.
o "m2" is the number of times that rcu_try_flip_waitmb() finds that
all CPUs have executed a memory barrier.
Hierarchical RCU debugfs Files and Formats
This implementation of RCU provides three debugfs files under the
top-level directory RCU: rcu/rcudata (which displays fields in struct
rcu_data), rcu/rcugp (which displays grace-period counters), and
rcu/rcuhier (which displays the struct rcu_node hierarchy).
The output of "cat rcu/rcudata" looks as follows:
rcu:
0 c=4011 g=4012 pq=1 pqc=4011 qp=0 rpfq=1 rp=3c2a dt=23301/73 dn=2 df=1882 of=0 ri=2126 ql=2 b=10
1 c=4011 g=4012 pq=1 pqc=4011 qp=0 rpfq=3 rp=39a6 dt=78073/1 dn=2 df=1402 of=0 ri=1875 ql=46 b=10
2 c=4010 g=4010 pq=1 pqc=4010 qp=0 rpfq=-5 rp=1d12 dt=16646/0 dn=2 df=3140 of=0 ri=2080 ql=0 b=10
3 c=4012 g=4013 pq=1 pqc=4012 qp=1 rpfq=3 rp=2b50 dt=21159/1 dn=2 df=2230 of=0 ri=1923 ql=72 b=10
4 c=4012 g=4013 pq=1 pqc=4012 qp=1 rpfq=3 rp=1644 dt=5783/1 dn=2 df=3348 of=0 ri=2805 ql=7 b=10
5 c=4012 g=4013 pq=0 pqc=4011 qp=1 rpfq=3 rp=1aac dt=5879/1 dn=2 df=3140 of=0 ri=2066 ql=10 b=10
6 c=4012 g=4013 pq=1 pqc=4012 qp=1 rpfq=3 rp=ed8 dt=5847/1 dn=2 df=3797 of=0 ri=1266 ql=10 b=10
7 c=4012 g=4013 pq=1 pqc=4012 qp=1 rpfq=3 rp=1fa2 dt=6199/1 dn=2 df=2795 of=0 ri=2162 ql=28 b=10
rcu_bh:
0 c=-268 g=-268 pq=1 pqc=-268 qp=0 rpfq=-145 rp=21d6 dt=23301/73 dn=2 df=0 of=0 ri=0 ql=0 b=10
1 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-170 rp=20ce dt=78073/1 dn=2 df=26 of=0 ri=5 ql=0 b=10
2 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-83 rp=fbd dt=16646/0 dn=2 df=28 of=0 ri=4 ql=0 b=10
3 c=-268 g=-268 pq=1 pqc=-268 qp=0 rpfq=-105 rp=178c dt=21159/1 dn=2 df=28 of=0 ri=2 ql=0 b=10
4 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-30 rp=b54 dt=5783/1 dn=2 df=32 of=0 ri=0 ql=0 b=10
5 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-29 rp=df5 dt=5879/1 dn=2 df=30 of=0 ri=3 ql=0 b=10
6 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-28 rp=788 dt=5847/1 dn=2 df=32 of=0 ri=0 ql=0 b=10
7 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-53 rp=1098 dt=6199/1 dn=2 df=30 of=0 ri=3 ql=0 b=10
The first section lists the rcu_data structures for rcu, the second for
rcu_bh. Each section has one line per CPU, or eight for this 8-CPU system.
The fields are as follows:
o The number at the beginning of each line is the CPU number.
CPUs numbers followed by an exclamation mark are offline,
but have been online at least once since boot. There will be
no output for CPUs that have never been online, which can be
a good thing in the surprisingly common case where NR_CPUS is
substantially larger than the number of actual CPUs.
o "c" is the count of grace periods that this CPU believes have
completed. CPUs in dynticks idle mode may lag quite a ways
behind, for example, CPU 4 under "rcu" above, which has slept
through the past 25 RCU grace periods. It is not unusual to
see CPUs lagging by thousands of grace periods.
o "g" is the count of grace periods that this CPU believes have
started. Again, CPUs in dynticks idle mode may lag behind.
If the "c" and "g" values are equal, this CPU has already
reported a quiescent state for the last RCU grace period that
it is aware of, otherwise, the CPU believes that it owes RCU a
quiescent state.
o "pq" indicates that this CPU has passed through a quiescent state
for the current grace period. It is possible for "pq" to be
"1" and "c" different than "g", which indicates that although
the CPU has passed through a quiescent state, either (1) this
CPU has not yet reported that fact, (2) some other CPU has not
yet reported for this grace period, or (3) both.
o "pqc" indicates which grace period the last-observed quiescent
state for this CPU corresponds to. This is important for handling
the race between CPU 0 reporting an extended dynticks-idle
quiescent state for CPU 1 and CPU 1 suddenly waking up and
reporting its own quiescent state. If CPU 1 was the last CPU
for the current grace period, then the CPU that loses this race
will attempt to incorrectly mark CPU 1 as having checked in for
the next grace period!
o "qp" indicates that RCU still expects a quiescent state from
this CPU.
o "rpfq" is the number of rcu_pending() calls on this CPU required
to induce this CPU to invoke force_quiescent_state().
o "rp" is low-order four hex digits of the count of how many times
rcu_pending() has been invoked on this CPU.
o "dt" is the current value of the dyntick counter that is incremented
when entering or leaving dynticks idle state, either by the
scheduler or by irq. The number after the "/" is the interrupt
nesting depth when in dyntick-idle state, or one greater than
the interrupt-nesting depth otherwise.
This field is displayed only for CONFIG_NO_HZ kernels.
o "dn" is the current value of the dyntick counter that is incremented
when entering or leaving dynticks idle state via NMI. If both
the "dt" and "dn" values are even, then this CPU is in dynticks
idle mode and may be ignored by RCU. If either of these two
counters is odd, then RCU must be alert to the possibility of
an RCU read-side critical section running on this CPU.
This field is displayed only for CONFIG_NO_HZ kernels.
o "df" is the number of times that some other CPU has forced a
quiescent state on behalf of this CPU due to this CPU being in
dynticks-idle state.
This field is displayed only for CONFIG_NO_HZ kernels.
o "of" is the number of times that some other CPU has forced a
quiescent state on behalf of this CPU due to this CPU being
offline. In a perfect world, this might neve happen, but it
turns out that offlining and onlining a CPU can take several grace
periods, and so there is likely to be an extended period of time
when RCU believes that the CPU is online when it really is not.
Please note that erring in the other direction (RCU believing a
CPU is offline when it is really alive and kicking) is a fatal
error, so it makes sense to err conservatively.
o "ri" is the number of times that RCU has seen fit to send a
reschedule IPI to this CPU in order to get it to report a
quiescent state.
o "ql" is the number of RCU callbacks currently residing on
this CPU. This is the total number of callbacks, regardless
of what state they are in (new, waiting for grace period to
start, waiting for grace period to end, ready to invoke).
o "b" is the batch limit for this CPU. If more than this number
of RCU callbacks is ready to invoke, then the remainder will
be deferred.
The output of "cat rcu/rcugp" looks as follows:
rcu: completed=33062 gpnum=33063
rcu_bh: completed=464 gpnum=464
Again, this output is for both "rcu" and "rcu_bh". The fields are
taken from the rcu_state structure, and are as follows:
o "completed" is the number of grace periods that have completed.
It is comparable to the "c" field from rcu/rcudata in that a
CPU whose "c" field matches the value of "completed" is aware
that the corresponding RCU grace period has completed.
o "gpnum" is the number of grace periods that have started. It is
comparable to the "g" field from rcu/rcudata in that a CPU
whose "g" field matches the value of "gpnum" is aware that the
corresponding RCU grace period has started.
If these two fields are equal (as they are for "rcu_bh" above),
then there is no grace period in progress, in other words, RCU
is idle. On the other hand, if the two fields differ (as they
do for "rcu" above), then an RCU grace period is in progress.
The output of "cat rcu/rcuhier" looks as follows, with very long lines:
c=6902 g=6903 s=2 jfq=3 j=72c7 nfqs=13142/nfqsng=0(13142) fqlh=6
1/1 0:127 ^0
3/3 0:35 ^0 0/0 36:71 ^1 0/0 72:107 ^2 0/0 108:127 ^3
3/3f 0:5 ^0 2/3 6:11 ^1 0/0 12:17 ^2 0/0 18:23 ^3 0/0 24:29 ^4 0/0 30:35 ^5 0/0 36:41 ^0 0/0 42:47 ^1 0/0 48:53 ^2 0/0 54:59 ^3 0/0 60:65 ^4 0/0 66:71 ^5 0/0 72:77 ^0 0/0 78:83 ^1 0/0 84:89 ^2 0/0 90:95 ^3 0/0 96:101 ^4 0/0 102:107 ^5 0/0 108:113 ^0 0/0 114:119 ^1 0/0 120:125 ^2 0/0 126:127 ^3
rcu_bh:
c=-226 g=-226 s=1 jfq=-5701 j=72c7 nfqs=88/nfqsng=0(88) fqlh=0
0/1 0:127 ^0
0/3 0:35 ^0 0/0 36:71 ^1 0/0 72:107 ^2 0/0 108:127 ^3
0/3f 0:5 ^0 0/3 6:11 ^1 0/0 12:17 ^2 0/0 18:23 ^3 0/0 24:29 ^4 0/0 30:35 ^5 0/0 36:41 ^0 0/0 42:47 ^1 0/0 48:53 ^2 0/0 54:59 ^3 0/0 60:65 ^4 0/0 66:71 ^5 0/0 72:77 ^0 0/0 78:83 ^1 0/0 84:89 ^2 0/0 90:95 ^3 0/0 96:101 ^4 0/0 102:107 ^5 0/0 108:113 ^0 0/0 114:119 ^1 0/0 120:125 ^2 0/0 126:127 ^3
This is once again split into "rcu" and "rcu_bh" portions. The fields are
as follows:
o "c" is exactly the same as "completed" under rcu/rcugp.
o "g" is exactly the same as "gpnum" under rcu/rcugp.
o "s" is the "signaled" state that drives force_quiescent_state()'s
state machine.
o "jfq" is the number of jiffies remaining for this grace period
before force_quiescent_state() is invoked to help push things
along. Note that CPUs in dyntick-idle mode thoughout the grace
period will not report on their own, but rather must be check by
some other CPU via force_quiescent_state().
o "j" is the low-order four hex digits of the jiffies counter.
Yes, Paul did run into a number of problems that turned out to
be due to the jiffies counter no longer counting. Why do you ask?
o "nfqs" is the number of calls to force_quiescent_state() since
boot.
o "nfqsng" is the number of useless calls to force_quiescent_state(),
where there wasn't actually a grace period active. This can
happen due to races. The number in parentheses is the difference
between "nfqs" and "nfqsng", or the number of times that
force_quiescent_state() actually did some real work.
o "fqlh" is the number of calls to force_quiescent_state() that
exited immediately (without even being counted in nfqs above)
due to contention on ->fqslock.
o Each element of the form "1/1 0:127 ^0" represents one struct
rcu_node. Each line represents one level of the hierarchy, from
root to leaves. It is best to think of the rcu_data structures
as forming yet another level after the leaves. Note that there
might be either one, two, or three levels of rcu_node structures,
depending on the relationship between CONFIG_RCU_FANOUT and
CONFIG_NR_CPUS.
o The numbers separated by the "/" are the qsmask followed
by the qsmaskinit. The qsmask will have one bit
set for each entity in the next lower level that
has not yet checked in for the current grace period.
The qsmaskinit will have one bit for each entity that is
currently expected to check in during each grace period.
The value of qsmaskinit is assigned to that of qsmask
at the beginning of each grace period.
For example, for "rcu", the qsmask of the first entry
of the lowest level is 0x14, meaning that we are still
waiting for CPUs 2 and 4 to check in for the current
grace period.
o The numbers separated by the ":" are the range of CPUs
served by this struct rcu_node. This can be helpful
in working out how the hierarchy is wired together.
For example, the first entry at the lowest level shows
"0:5", indicating that it covers CPUs 0 through 5.
o The number after the "^" indicates the bit in the
next higher level rcu_node structure that this
rcu_node structure corresponds to.
For example, the first entry at the lowest level shows
"^0", indicating that it corresponds to bit zero in
the first entry at the middle level.

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MFP Configuration for PXA2xx/PXA3xx Processors
Eric Miao <eric.miao@marvell.com>
MFP stands for Multi-Function Pin, which is the pin-mux logic on PXA3xx and
later PXA series processors. This document describes the existing MFP API,
and how board/platform driver authors could make use of it.
Basic Concept
===============
Unlike the GPIO alternate function settings on PXA25x and PXA27x, a new MFP
mechanism is introduced from PXA3xx to completely move the pin-mux functions
out of the GPIO controller. In addition to pin-mux configurations, the MFP
also controls the low power state, driving strength, pull-up/down and event
detection of each pin. Below is a diagram of internal connections between
the MFP logic and the remaining SoC peripherals:
+--------+
| |--(GPIO19)--+
| GPIO | |
| |--(GPIO...) |
+--------+ |
| +---------+
+--------+ +------>| |
| PWM2 |--(PWM_OUT)-------->| MFP |
+--------+ +------>| |-------> to external PAD
| +---->| |
+--------+ | | +-->| |
| SSP2 |---(TXD)----+ | | +---------+
+--------+ | |
| |
+--------+ | |
| Keypad |--(MKOUT4)----+ |
+--------+ |
|
+--------+ |
| UART2 |---(TXD)--------+
+--------+
NOTE: the external pad is named as MFP_PIN_GPIO19, it doesn't necessarily
mean it's dedicated for GPIO19, only as a hint that internally this pin
can be routed from GPIO19 of the GPIO controller.
To better understand the change from PXA25x/PXA27x GPIO alternate function
to this new MFP mechanism, here are several key points:
1. GPIO controller on PXA3xx is now a dedicated controller, same as other
internal controllers like PWM, SSP and UART, with 128 internal signals
which can be routed to external through one or more MFPs (e.g. GPIO<0>
can be routed through either MFP_PIN_GPIO0 as well as MFP_PIN_GPIO0_2,
see arch/arm/mach-pxa/mach/include/mfp-pxa300.h)
2. Alternate function configuration is removed from this GPIO controller,
the remaining functions are pure GPIO-specific, i.e.
- GPIO signal level control
- GPIO direction control
- GPIO level change detection
3. Low power state for each pin is now controlled by MFP, this means the
PGSRx registers on PXA2xx are now useless on PXA3xx
4. Wakeup detection is now controlled by MFP, PWER does not control the
wakeup from GPIO(s) any more, depending on the sleeping state, ADxER
(as defined in pxa3xx-regs.h) controls the wakeup from MFP
NOTE: with such a clear separation of MFP and GPIO, by GPIO<xx> we normally
mean it is a GPIO signal, and by MFP<xxx> or pin xxx, we mean a physical
pad (or ball).
MFP API Usage
===============
For board code writers, here are some guidelines:
1. include ONE of the following header files in your <board>.c:
- #include <mach/mfp-pxa25x.h>
- #include <mach/mfp-pxa27x.h>
- #include <mach/mfp-pxa300.h>
- #include <mach/mfp-pxa320.h>
- #include <mach/mfp-pxa930.h>
NOTE: only one file in your <board>.c, depending on the processors used,
because pin configuration definitions may conflict in these file (i.e.
same name, different meaning and settings on different processors). E.g.
for zylonite platform, which support both PXA300/PXA310 and PXA320, two
separate files are introduced: zylonite_pxa300.c and zylonite_pxa320.c
(in addition to handle MFP configuration differences, they also handle
the other differences between the two combinations).
NOTE: PXA300 and PXA310 are almost identical in pin configurations (with
PXA310 supporting some additional ones), thus the difference is actually
covered in a single mfp-pxa300.h.
2. prepare an array for the initial pin configurations, e.g.:
static unsigned long mainstone_pin_config[] __initdata = {
/* Chip Select */
GPIO15_nCS_1,
/* LCD - 16bpp Active TFT */
GPIOxx_TFT_LCD_16BPP,
GPIO16_PWM0_OUT, /* Backlight */
/* MMC */
GPIO32_MMC_CLK,
GPIO112_MMC_CMD,
GPIO92_MMC_DAT_0,
GPIO109_MMC_DAT_1,
GPIO110_MMC_DAT_2,
GPIO111_MMC_DAT_3,
...
/* GPIO */
GPIO1_GPIO | WAKEUP_ON_EDGE_BOTH,
};
a) once the pin configurations are passed to pxa{2xx,3xx}_mfp_config(),
and written to the actual registers, they are useless and may discard,
adding '__initdata' will help save some additional bytes here.
b) when there is only one possible pin configurations for a component,
some simplified definitions can be used, e.g. GPIOxx_TFT_LCD_16BPP on
PXA25x and PXA27x processors
c) if by board design, a pin can be configured to wake up the system
from low power state, it can be 'OR'ed with any of:
WAKEUP_ON_EDGE_BOTH
WAKEUP_ON_EDGE_RISE
WAKEUP_ON_EDGE_FALL
WAKEUP_ON_LEVEL_HIGH - specifically for enabling of keypad GPIOs,
to indicate that this pin has the capability of wake-up the system,
and on which edge(s). This, however, doesn't necessarily mean the
pin _will_ wakeup the system, it will only when set_irq_wake() is
invoked with the corresponding GPIO IRQ (GPIO_IRQ(xx) or gpio_to_irq())
and eventually calls gpio_set_wake() for the actual register setting.
d) although PXA3xx MFP supports edge detection on each pin, the
internal logic will only wakeup the system when those specific bits
in ADxER registers are set, which can be well mapped to the
corresponding peripheral, thus set_irq_wake() can be called with
the peripheral IRQ to enable the wakeup.
MFP on PXA3xx
===============
Every external I/O pad on PXA3xx (excluding those for special purpose) has
one MFP logic associated, and is controlled by one MFP register (MFPR).
The MFPR has the following bit definitions (for PXA300/PXA310/PXA320):
31 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
+-------------------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| RESERVED |PS|PU|PD| DRIVE |SS|SD|SO|EC|EF|ER|--| AF_SEL |
+-------------------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
Bit 3: RESERVED
Bit 4: EDGE_RISE_EN - enable detection of rising edge on this pin
Bit 5: EDGE_FALL_EN - enable detection of falling edge on this pin
Bit 6: EDGE_CLEAR - disable edge detection on this pin
Bit 7: SLEEP_OE_N - enable outputs during low power modes
Bit 8: SLEEP_DATA - output data on the pin during low power modes
Bit 9: SLEEP_SEL - selection control for low power modes signals
Bit 13: PULLDOWN_EN - enable the internal pull-down resistor on this pin
Bit 14: PULLUP_EN - enable the internal pull-up resistor on this pin
Bit 15: PULL_SEL - pull state controlled by selected alternate function
(0) or by PULL{UP,DOWN}_EN bits (1)
Bit 0 - 2: AF_SEL - alternate function selection, 8 possibilities, from 0-7
Bit 10-12: DRIVE - drive strength and slew rate
0b000 - fast 1mA
0b001 - fast 2mA
0b002 - fast 3mA
0b003 - fast 4mA
0b004 - slow 6mA
0b005 - fast 6mA
0b006 - slow 10mA
0b007 - fast 10mA
MFP Design for PXA2xx/PXA3xx
==============================
Due to the difference of pin-mux handling between PXA2xx and PXA3xx, a unified
MFP API is introduced to cover both series of processors.
The basic idea of this design is to introduce definitions for all possible pin
configurations, these definitions are processor and platform independent, and
the actual API invoked to convert these definitions into register settings and
make them effective there-after.
Files Involved
--------------
- arch/arm/mach-pxa/include/mach/mfp.h
for
1. Unified pin definitions - enum constants for all configurable pins
2. processor-neutral bit definitions for a possible MFP configuration
- arch/arm/mach-pxa/include/mach/mfp-pxa3xx.h
for PXA3xx specific MFPR register bit definitions and PXA3xx common pin
configurations
- arch/arm/mach-pxa/include/mach/mfp-pxa2xx.h
for PXA2xx specific definitions and PXA25x/PXA27x common pin configurations
- arch/arm/mach-pxa/include/mach/mfp-pxa25x.h
arch/arm/mach-pxa/include/mach/mfp-pxa27x.h
arch/arm/mach-pxa/include/mach/mfp-pxa300.h
arch/arm/mach-pxa/include/mach/mfp-pxa320.h
arch/arm/mach-pxa/include/mach/mfp-pxa930.h
for processor specific definitions
- arch/arm/mach-pxa/mfp-pxa3xx.c
- arch/arm/mach-pxa/mfp-pxa2xx.c
for implementation of the pin configuration to take effect for the actual
processor.
Pin Configuration
-----------------
The following comments are copied from mfp.h (see the actual source code
for most updated info)
/*
* a possible MFP configuration is represented by a 32-bit integer
*
* bit 0.. 9 - MFP Pin Number (1024 Pins Maximum)
* bit 10..12 - Alternate Function Selection
* bit 13..15 - Drive Strength
* bit 16..18 - Low Power Mode State
* bit 19..20 - Low Power Mode Edge Detection
* bit 21..22 - Run Mode Pull State
*
* to facilitate the definition, the following macros are provided
*
* MFP_CFG_DEFAULT - default MFP configuration value, with
* alternate function = 0,
* drive strength = fast 3mA (MFP_DS03X)
* low power mode = default
* edge detection = none
*
* MFP_CFG - default MFPR value with alternate function
* MFP_CFG_DRV - default MFPR value with alternate function and
* pin drive strength
* MFP_CFG_LPM - default MFPR value with alternate function and
* low power mode
* MFP_CFG_X - default MFPR value with alternate function,
* pin drive strength and low power mode
*/
Examples of pin configurations are:
#define GPIO94_SSP3_RXD MFP_CFG_X(GPIO94, AF1, DS08X, FLOAT)
which reads GPIO94 can be configured as SSP3_RXD, with alternate function
selection of 1, driving strength of 0b101, and a float state in low power
modes.
NOTE: this is the default setting of this pin being configured as SSP3_RXD
which can be modified a bit in board code, though it is not recommended to
do so, simply because this default setting is usually carefully encoded,
and is supposed to work in most cases.
Register Settings
-----------------
Register settings on PXA3xx for a pin configuration is actually very
straight-forward, most bits can be converted directly into MFPR value
in a easier way. Two sets of MFPR values are calculated: the run-time
ones and the low power mode ones, to allow different settings.
The conversion from a generic pin configuration to the actual register
settings on PXA2xx is a bit complicated: many registers are involved,
including GAFRx, GPDRx, PGSRx, PWER, PKWR, PFER and PRER. Please see
mfp-pxa2xx.c for how the conversion is made.

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March 2008
Jan-Simon Moeller, dl9pf@gmx.de
How to deal with bad memory e.g. reported by memtest86+ ?
#########################################################
There are three possibilities I know of:
1) Reinsert/swap the memory modules
2) Buy new modules (best!) or try to exchange the memory
if you have spare-parts
3) Use BadRAM or memmap
This Howto is about number 3) .
BadRAM
######
BadRAM is the actively developed and available as kernel-patch
here: http://rick.vanrein.org/linux/badram/
For more details see the BadRAM documentation.
memmap
######
memmap is already in the kernel and usable as kernel-parameter at
boot-time. Its syntax is slightly strange and you may need to
calculate the values by yourself!
Syntax to exclude a memory area (see kernel-parameters.txt for details):
memmap=<size>$<address>
Example: memtest86+ reported here errors at address 0x18691458, 0x18698424 and
some others. All had 0x1869xxxx in common, so I chose a pattern of
0x18690000,0xffff0000.
With the numbers of the example above:
memmap=64K$0x18690000
or
memmap=0x10000$0x18690000

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@ -9,3 +9,6 @@ cachefeatures.txt
Filesystems
- Requirements for mounting the root file system.
bfin-gpio-note.txt
- Notes in developing/using bfin-gpio driver.

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/*
* File: Documentation/blackfin/bfin-gpio-note.txt
* Based on:
* Author:
*
* Created: $Id: bfin-gpio-note.txt 2008-11-24 16:42 grafyang $
* Description: This file contains the notes in developing/using bfin-gpio.
*
*
* Rev:
*
* Modified:
* Copyright 2004-2008 Analog Devices Inc.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
*/
1. Blackfin GPIO introduction
There are many GPIO pins on Blackfin. Most of these pins are muxed to
multi-functions. They can be configured as peripheral, or just as GPIO,
configured to input with interrupt enabled, or output.
For detailed information, please see "arch/blackfin/kernel/bfin_gpio.c",
or the relevant HRM.
2. Avoiding resource conflict
Followed function groups are used to avoiding resource conflict,
- Use the pin as peripheral,
int peripheral_request(unsigned short per, const char *label);
int peripheral_request_list(const unsigned short per[], const char *label);
void peripheral_free(unsigned short per);
void peripheral_free_list(const unsigned short per[]);
- Use the pin as GPIO,
int bfin_gpio_request(unsigned gpio, const char *label);
void bfin_gpio_free(unsigned gpio);
- Use the pin as GPIO interrupt,
int bfin_gpio_irq_request(unsigned gpio, const char *label);
void bfin_gpio_irq_free(unsigned gpio);
The request functions will record the function state for a certain pin,
the free functions will clear it's function state.
Once a pin is requested, it can't be requested again before it is freed by
previous caller, otherwise kernel will dump stacks, and the request
function fail.
These functions are wrapped by other functions, most of the users need not
care.
3. But there are some exceptions
- Kernel permit the identical GPIO be requested both as GPIO and GPIO
interrut.
Some drivers, like gpio-keys, need this behavior. Kernel only print out
warning messages like,
bfin-gpio: GPIO 24 is already reserved by gpio-keys: BTN0, and you are
configuring it as IRQ!
Note: Consider the case that, if there are two drivers need the
identical GPIO, one of them use it as GPIO, the other use it as
GPIO interrupt. This will really cause resource conflict. So if
there is any abnormal driver behavior, please check the bfin-gpio
warning messages.
- Kernel permit the identical GPIO be requested from the same driver twice.

6
Documentation/block/biodoc.txt
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@ -914,7 +914,7 @@ I/O scheduler, a.k.a. elevator, is implemented in two layers. Generic dispatch
queue and specific I/O schedulers. Unless stated otherwise, elevator is used
to refer to both parts and I/O scheduler to specific I/O schedulers.
Block layer implements generic dispatch queue in ll_rw_blk.c and elevator.c.
Block layer implements generic dispatch queue in block/*.c.
The generic dispatch queue is responsible for properly ordering barrier
requests, requeueing, handling non-fs requests and all other subtleties.
@ -926,8 +926,8 @@ be built inside the kernel. Each queue can choose different one and can also
change to another one dynamically.
A block layer call to the i/o scheduler follows the convention elv_xxx(). This
calls elevator_xxx_fn in the elevator switch (drivers/block/elevator.c). Oh,
xxx and xxx might not match exactly, but use your imagination. If an elevator
calls elevator_xxx_fn in the elevator switch (block/elevator.c). Oh, xxx
and xxx might not match exactly, but use your imagination. If an elevator
doesn't implement a function, the switch does nothing or some minimal house
keeping work.

9
Documentation/cgroups/cgroups.txt
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@ -227,7 +227,6 @@ Each cgroup is represented by a directory in the cgroup file system
containing the following files describing that cgroup:
- tasks: list of tasks (by pid) attached to that cgroup
- releasable flag: cgroup currently removeable?
- notify_on_release flag: run the release agent on exit?
- release_agent: the path to use for release notifications (this file
exists in the top cgroup only)
@ -360,7 +359,7 @@ Now you want to do something with this cgroup.
In this directory you can find several files:
# ls
notify_on_release releasable tasks
notify_on_release tasks
(plus whatever files added by the attached subsystems)
Now attach your shell to this cgroup:
@ -479,7 +478,6 @@ newly-created cgroup if an error occurs after this subsystem's
create() method has been called for the new cgroup).
void pre_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp);
(cgroup_mutex held by caller)
Called before checking the reference count on each subsystem. This may
be useful for subsystems which have some extra references even if
@ -498,6 +496,7 @@ remain valid while the caller holds cgroup_mutex.
void attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
struct cgroup *old_cgrp, struct task_struct *task)
(cgroup_mutex held by caller)
Called after the task has been attached to the cgroup, to allow any
post-attachment activity that requires memory allocations or blocking.
@ -511,6 +510,7 @@ void exit(struct cgroup_subsys *ss, struct task_struct *task)
Called during task exit.
int populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
(cgroup_mutex held by caller)
Called after creation of a cgroup to allow a subsystem to populate
the cgroup directory with file entries. The subsystem should make
@ -520,6 +520,7 @@ method can return an error code, the error code is currently not
always handled well.
void post_clone(struct cgroup_subsys *ss, struct cgroup *cgrp)
(cgroup_mutex held by caller)
Called at the end of cgroup_clone() to do any paramater
initialization which might be required before a task could attach. For
@ -527,7 +528,7 @@ example in cpusets, no task may attach before 'cpus' and 'mems' are set
up.
void bind(struct cgroup_subsys *ss, struct cgroup *root)
(cgroup_mutex held by caller)
(cgroup_mutex and ss->hierarchy_mutex held by caller)
Called when a cgroup subsystem is rebound to a different hierarchy
and root cgroup. Currently this will only involve movement between

342
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@ -0,0 +1,342 @@
Memory Resource Controller(Memcg) Implementation Memo.
Last Updated: 2008/12/15
Base Kernel Version: based on 2.6.28-rc8-mm.
Because VM is getting complex (one of reasons is memcg...), memcg's behavior
is complex. This is a document for memcg's internal behavior.
Please note that implementation details can be changed.
(*) Topics on API should be in Documentation/controllers/memory.txt)
0. How to record usage ?
2 objects are used.
page_cgroup ....an object per page.
Allocated at boot or memory hotplug. Freed at memory hot removal.
swap_cgroup ... an entry per swp_entry.
Allocated at swapon(). Freed at swapoff().
The page_cgroup has USED bit and double count against a page_cgroup never
occurs. swap_cgroup is used only when a charged page is swapped-out.
1. Charge
a page/swp_entry may be charged (usage += PAGE_SIZE) at
mem_cgroup_newpage_charge()
Called at new page fault and Copy-On-Write.
mem_cgroup_try_charge_swapin()
Called at do_swap_page() (page fault on swap entry) and swapoff.
Followed by charge-commit-cancel protocol. (With swap accounting)
At commit, a charge recorded in swap_cgroup is removed.
mem_cgroup_cache_charge()
Called at add_to_page_cache()
mem_cgroup_cache_charge_swapin()
Called at shmem's swapin.
mem_cgroup_prepare_migration()
Called before migration. "extra" charge is done and followed by
charge-commit-cancel protocol.
At commit, charge against oldpage or newpage will be committed.
2. Uncharge
a page/swp_entry may be uncharged (usage -= PAGE_SIZE) by
mem_cgroup_uncharge_page()
Called when an anonymous page is fully unmapped. I.e., mapcount goes
to 0. If the page is SwapCache, uncharge is delayed until
mem_cgroup_uncharge_swapcache().
mem_cgroup_uncharge_cache_page()
Called when a page-cache is deleted from radix-tree. If the page is
SwapCache, uncharge is delayed until mem_cgroup_uncharge_swapcache().
mem_cgroup_uncharge_swapcache()
Called when SwapCache is removed from radix-tree. The charge itself
is moved to swap_cgroup. (If mem+swap controller is disabled, no
charge to swap occurs.)
mem_cgroup_uncharge_swap()
Called when swp_entry's refcnt goes down to 0. A charge against swap
disappears.
mem_cgroup_end_migration(old, new)
At success of migration old is uncharged (if necessary), a charge
to new page is committed. At failure, charge to old page is committed.
3. charge-commit-cancel
In some case, we can't know this "charge" is valid or not at charging
(because of races).
To handle such case, there are charge-commit-cancel functions.
mem_cgroup_try_charge_XXX
mem_cgroup_commit_charge_XXX
mem_cgroup_cancel_charge_XXX
these are used in swap-in and migration.
At try_charge(), there are no flags to say "this page is charged".
at this point, usage += PAGE_SIZE.
At commit(), the function checks the page should be charged or not
and set flags or avoid charging.(usage -= PAGE_SIZE)
At cancel(), simply usage -= PAGE_SIZE.
Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y.
4. Anonymous
Anonymous page is newly allocated at
- page fault into MAP_ANONYMOUS mapping.
- Copy-On-Write.
It is charged right after it's allocated before doing any page table
related operations. Of course, it's uncharged when another page is used
for the fault address.
At freeing anonymous page (by exit() or munmap()), zap_pte() is called
and pages for ptes are freed one by one.(see mm/memory.c). Uncharges
are done at page_remove_rmap() when page_mapcount() goes down to 0.
Another page freeing is by page-reclaim (vmscan.c) and anonymous
pages are swapped out. In this case, the page is marked as
PageSwapCache(). uncharge() routine doesn't uncharge the page marked
as SwapCache(). It's delayed until __delete_from_swap_cache().
4.1 Swap-in.
At swap-in, the page is taken from swap-cache. There are 2 cases.
(a) If the SwapCache is newly allocated and read, it has no charges.
(b) If the SwapCache has been mapped by processes, it has been
charged already.
This swap-in is one of the most complicated work. In do_swap_page(),
following events occur when pte is unchanged.
(1) the page (SwapCache) is looked up.
(2) lock_page()
(3) try_charge_swapin()
(4) reuse_swap_page() (may call delete_swap_cache())
(5) commit_charge_swapin()
(6) swap_free().
Considering following situation for example.
(A) The page has not been charged before (2) and reuse_swap_page()
doesn't call delete_from_swap_cache().
(B) The page has not been charged before (2) and reuse_swap_page()
calls delete_from_swap_cache().
(C) The page has been charged before (2) and reuse_swap_page() doesn't
call delete_from_swap_cache().
(D) The page has been charged before (2) and reuse_swap_page() calls
delete_from_swap_cache().
memory.usage/memsw.usage changes to this page/swp_entry will be
Case (A) (B) (C) (D)
Event
Before (2) 0/ 1 0/ 1 1/ 1 1/ 1
===========================================
(3) +1/+1 +1/+1 +1/+1 +1/+1
(4) - 0/ 0 - -1/ 0
(5) 0/-1 0/ 0 -1/-1 0/ 0
(6) - 0/-1 - 0/-1
===========================================
Result 1/ 1 1/ 1 1/ 1 1/ 1
In any cases, charges to this page should be 1/ 1.
4.2 Swap-out.
At swap-out, typical state transition is below.
(a) add to swap cache. (marked as SwapCache)
swp_entry's refcnt += 1.
(b) fully unmapped.
swp_entry's refcnt += # of ptes.
(c) write back to swap.
(d) delete from swap cache. (remove from SwapCache)
swp_entry's refcnt -= 1.
At (b), the page is marked as SwapCache and not uncharged.
At (d), the page is removed from SwapCache and a charge in page_cgroup
is moved to swap_cgroup.
Finally, at task exit,
(e) zap_pte() is called and swp_entry's refcnt -=1 -> 0.
Here, a charge in swap_cgroup disappears.
5. Page Cache
Page Cache is charged at
- add_to_page_cache_locked().
uncharged at
- __remove_from_page_cache().
The logic is very clear. (About migration, see below)
Note: __remove_from_page_cache() is called by remove_from_page_cache()
and __remove_mapping().
6. Shmem(tmpfs) Page Cache
Memcg's charge/uncharge have special handlers of shmem. The best way
to understand shmem's page state transition is to read mm/shmem.c.
But brief explanation of the behavior of memcg around shmem will be
helpful to understand the logic.
Shmem's page (just leaf page, not direct/indirect block) can be on
- radix-tree of shmem's inode.
- SwapCache.
- Both on radix-tree and SwapCache. This happens at swap-in
and swap-out,
It's charged when...
- A new page is added to shmem's radix-tree.
- A swp page is read. (move a charge from swap_cgroup to page_cgroup)
It's uncharged when
- A page is removed from radix-tree and not SwapCache.
- When SwapCache is removed, a charge is moved to swap_cgroup.
- When swp_entry's refcnt goes down to 0, a charge in swap_cgroup
disappears.
7. Page Migration
One of the most complicated functions is page-migration-handler.
Memcg has 2 routines. Assume that we are migrating a page's contents
from OLDPAGE to NEWPAGE.
Usual migration logic is..
(a) remove the page from LRU.
(b) allocate NEWPAGE (migration target)
(c) lock by lock_page().
(d) unmap all mappings.
(e-1) If necessary, replace entry in radix-tree.
(e-2) move contents of a page.
(f) map all mappings again.
(g) pushback the page to LRU.
(-) OLDPAGE will be freed.
Before (g), memcg should complete all necessary charge/uncharge to
NEWPAGE/OLDPAGE.
The point is....
- If OLDPAGE is anonymous, all charges will be dropped at (d) because
try_to_unmap() drops all mapcount and the page will not be
SwapCache.
- If OLDPAGE is SwapCache, charges will be kept at (g) because
__delete_from_swap_cache() isn't called at (e-1)
- If OLDPAGE is page-cache, charges will be kept at (g) because
remove_from_swap_cache() isn't called at (e-1)
memcg provides following hooks.
- mem_cgroup_prepare_migration(OLDPAGE)
Called after (b) to account a charge (usage += PAGE_SIZE) against
memcg which OLDPAGE belongs to.
- mem_cgroup_end_migration(OLDPAGE, NEWPAGE)
Called after (f) before (g).
If OLDPAGE is used, commit OLDPAGE again. If OLDPAGE is already
charged, a charge by prepare_migration() is automatically canceled.
If NEWPAGE is used, commit NEWPAGE and uncharge OLDPAGE.
But zap_pte() (by exit or munmap) can be called while migration,
we have to check if OLDPAGE/NEWPAGE is a valid page after commit().
8. LRU
Each memcg has its own private LRU. Now, it's handling is under global
VM's control (means that it's handled under global zone->lru_lock).
Almost all routines around memcg's LRU is called by global LRU's
list management functions under zone->lru_lock().
A special function is mem_cgroup_isolate_pages(). This scans
memcg's private LRU and call __isolate_lru_page() to extract a page
from LRU.
(By __isolate_lru_page(), the page is removed from both of global and
private LRU.)
9. Typical Tests.
Tests for racy cases.
9.1 Small limit to memcg.
When you do test to do racy case, it's good test to set memcg's limit
to be very small rather than GB. Many races found in the test under
xKB or xxMB limits.
(Memory behavior under GB and Memory behavior under MB shows very
different situation.)
9.2 Shmem
Historically, memcg's shmem handling was poor and we saw some amount
of troubles here. This is because shmem is page-cache but can be
SwapCache. Test with shmem/tmpfs is always good test.
9.3 Migration
For NUMA, migration is an another special case. To do easy test, cpuset
is useful. Following is a sample script to do migration.
mount -t cgroup -o cpuset none /opt/cpuset
mkdir /opt/cpuset/01
echo 1 > /opt/cpuset/01/cpuset.cpus
echo 0 > /opt/cpuset/01/cpuset.mems
echo 1 > /opt/cpuset/01/cpuset.memory_migrate
mkdir /opt/cpuset/02
echo 1 > /opt/cpuset/02/cpuset.cpus
echo 1 > /opt/cpuset/02/cpuset.mems
echo 1 > /opt/cpuset/02/cpuset.memory_migrate
In above set, when you moves a task from 01 to 02, page migration to
node 0 to node 1 will occur. Following is a script to migrate all
under cpuset.
--
move_task()
{
for pid in $1
do
/bin/echo $pid >$2/tasks 2>/dev/null
echo -n $pid
echo -n " "
done
echo END
}
G1_TASK=`cat ${G1}/tasks`
G2_TASK=`cat ${G2}/tasks`
move_task "${G1_TASK}" ${G2} &
--
9.4 Memory hotplug.
memory hotplug test is one of good test.
to offline memory, do following.
# echo offline > /sys/devices/system/memory/memoryXXX/state
(XXX is the place of memory)
This is an easy way to test page migration, too.
9.5 mkdir/rmdir
When using hierarchy, mkdir/rmdir test should be done.
Use tests like the following.
echo 1 >/opt/cgroup/01/memory/use_hierarchy
mkdir /opt/cgroup/01/child_a
mkdir /opt/cgroup/01/child_b
set limit to 01.
add limit to 01/child_b
run jobs under child_a and child_b
create/delete following groups at random while jobs are running.
/opt/cgroup/01/child_a/child_aa
/opt/cgroup/01/child_b/child_bb
/opt/cgroup/01/child_c
running new jobs in new group is also good.
9.6 Mount with other subsystems.
Mounting with other subsystems is a good test because there is a
race and lock dependency with other cgroup subsystems.
example)
# mount -t cgroup none /cgroup -t cpuset,memory,cpu,devices
and do task move, mkdir, rmdir etc...under this.

135
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@ -137,7 +137,32 @@ behind this approach is that a cgroup that aggressively uses a shared
page will eventually get charged for it (once it is uncharged from
the cgroup that brought it in -- this will happen on memory pressure).
2.4 Reclaim
Exception: If CONFIG_CGROUP_CGROUP_MEM_RES_CTLR_SWAP is not used..
When you do swapoff and make swapped-out pages of shmem(tmpfs) to
be backed into memory in force, charges for pages are accounted against the
caller of swapoff rather than the users of shmem.
2.4 Swap Extension (CONFIG_CGROUP_MEM_RES_CTLR_SWAP)
Swap Extension allows you to record charge for swap. A swapped-in page is
charged back to original page allocator if possible.
When swap is accounted, following files are added.
- memory.memsw.usage_in_bytes.
- memory.memsw.limit_in_bytes.
usage of mem+swap is limited by memsw.limit_in_bytes.
Note: why 'mem+swap' rather than swap.
The global LRU(kswapd) can swap out arbitrary pages. Swap-out means
to move account from memory to swap...there is no change in usage of
mem+swap.
In other words, when we want to limit the usage of swap without affecting
global LRU, mem+swap limit is better than just limiting swap from OS point
of view.
2.5 Reclaim
Each cgroup maintains a per cgroup LRU that consists of an active
and inactive list. When a cgroup goes over its limit, we first try
@ -207,12 +232,6 @@ exceeded.
The memory.stat file gives accounting information. Now, the number of
caches, RSS and Active pages/Inactive pages are shown.
The memory.force_empty gives an interface to drop *all* charges by force.
# echo 1 > memory.force_empty
will drop all charges in cgroup. Currently, this is maintained for test.
4. Testing
Balbir posted lmbench, AIM9, LTP and vmmstress results [10] and [11].
@ -242,10 +261,106 @@ reclaimed.
A cgroup can be removed by rmdir, but as discussed in sections 4.1 and 4.2, a
cgroup might have some charge associated with it, even though all
tasks have migrated away from it. Such charges are automatically dropped at
rmdir() if there are no tasks.
tasks have migrated away from it.
Such charges are freed(at default) or moved to its parent. When moved,
both of RSS and CACHES are moved to parent.
If both of them are busy, rmdir() returns -EBUSY. See 5.1 Also.
5. TODO
Charges recorded in swap information is not updated at removal of cgroup.
Recorded information is discarded and a cgroup which uses swap (swapcache)
will be charged as a new owner of it.
5. Misc. interfaces.
5.1 force_empty
memory.force_empty interface is provided to make cgroup's memory usage empty.
You can use this interface only when the cgroup has no tasks.
When writing anything to this
# echo 0 > memory.force_empty
Almost all pages tracked by this memcg will be unmapped and freed. Some of
pages cannot be freed because it's locked or in-use. Such pages are moved
to parent and this cgroup will be empty. But this may return -EBUSY in
some too busy case.
Typical use case of this interface is that calling this before rmdir().
Because rmdir() moves all pages to parent, some out-of-use page caches can be
moved to the parent. If you want to avoid that, force_empty will be useful.
5.2 stat file
memory.stat file includes following statistics (now)
cache - # of pages from page-cache and shmem.
rss - # of pages from anonymous memory.
pgpgin - # of event of charging
pgpgout - # of event of uncharging
active_anon - # of pages on active lru of anon, shmem.
inactive_anon - # of pages on active lru of anon, shmem
active_file - # of pages on active lru of file-cache
inactive_file - # of pages on inactive lru of file cache
unevictable - # of pages cannot be reclaimed.(mlocked etc)
Below is depend on CONFIG_DEBUG_VM.
inactive_ratio - VM inernal parameter. (see mm/page_alloc.c)
recent_rotated_anon - VM internal parameter. (see mm/vmscan.c)
recent_rotated_file - VM internal parameter. (see mm/vmscan.c)
recent_scanned_anon - VM internal parameter. (see mm/vmscan.c)
recent_scanned_file - VM internal parameter. (see mm/vmscan.c)
Memo:
recent_rotated means recent frequency of lru rotation.
recent_scanned means recent # of scans to lru.
showing for better debug please see the code for meanings.
5.3 swappiness
Similar to /proc/sys/vm/swappiness, but affecting a hierarchy of groups only.
Following cgroup's swapiness can't be changed.
- root cgroup (uses /proc/sys/vm/swappiness).
- a cgroup which uses hierarchy and it has child cgroup.
- a cgroup which uses hierarchy and not the root of hierarchy.
6. Hierarchy support
The memory controller supports a deep hierarchy and hierarchical accounting.
The hierarchy is created by creating the appropriate cgroups in the
cgroup filesystem. Consider for example, the following cgroup filesystem
hierarchy
root
/ | \
/ | \
a b c
| \
| \
d e
In the diagram above, with hierarchical accounting enabled, all memory
usage of e, is accounted to its ancestors up until the root (i.e, c and root),
that has memory.use_hierarchy enabled. If one of the ancestors goes over its
limit, the reclaim algorithm reclaims from the tasks in the ancestor and the
children of the ancestor.
6.1 Enabling hierarchical accounting and reclaim
The memory controller by default disables the hierarchy feature. Support
can be enabled by writing 1 to memory.use_hierarchy file of the root cgroup
# echo 1 > memory.use_hierarchy
The feature can be disabled by
# echo 0 > memory.use_hierarchy
NOTE1: Enabling/disabling will fail if the cgroup already has other
cgroups created below it.
NOTE2: This feature can be enabled/disabled per subtree.
7. TODO
1. Add support for accounting huge pages (as a separate controller)
2. Make per-cgroup scanner reclaim not-shared pages first

17
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@ -50,16 +50,17 @@ additional_cpus=n (*) Use this to limit hotpluggable cpus. This option sets
cpu_possible_map = cpu_present_map + additional_cpus
(*) Option valid only for following architectures
- x86_64, ia64
- ia64
ia64 and x86_64 use the number of disabled local apics in ACPI tables MADT
to determine the number of potentially hot-pluggable cpus. The implementation
should only rely on this to count the # of cpus, but *MUST* not rely on the
apicid values in those tables for disabled apics. In the event BIOS doesn't
mark such hot-pluggable cpus as disabled entries, one could use this
parameter "additional_cpus=x" to represent those cpus in the cpu_possible_map.
ia64 uses the number of disabled local apics in ACPI tables MADT to
determine the number of potentially hot-pluggable cpus. The implementation
should only rely on this to count the # of cpus, but *MUST* not rely
on the apicid values in those tables for disabled apics. In the event
BIOS doesn't mark such hot-pluggable cpus as disabled entries, one could
use this parameter "additional_cpus=x" to represent those cpus in the
cpu_possible_map.
possible_cpus=n [s390 only] use this to set hotpluggable cpus.
possible_cpus=n [s390,x86_64] use this to set hotpluggable cpus.
This option sets possible_cpus bits in
cpu_possible_map. Thus keeping the numbers of bits set
constant even if the machine gets rebooted.

48
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@ -31,3 +31,51 @@ not defined by include/asm-XXX/topology.h:
2) core_id: 0
3) thread_siblings: just the given CPU
4) core_siblings: just the given CPU
Additionally, cpu topology information is provided under
/sys/devices/system/cpu and includes these files. The internal
source for the output is in brackets ("[]").
kernel_max: the maximum cpu index allowed by the kernel configuration.
[NR_CPUS-1]
offline: cpus that are not online because they have been
HOTPLUGGED off (see cpu-hotplug.txt) or exceed the limit
of cpus allowed by the kernel configuration (kernel_max
above). [~cpu_online_mask + cpus >= NR_CPUS]
online: cpus that are online and being scheduled [cpu_online_mask]
possible: cpus that have been allocated resources and can be
brought online if they are present. [cpu_possible_mask]
present: cpus that have been identified as being present in the
system. [cpu_present_mask]
The format for the above output is compatible with cpulist_parse()
[see <linux/cpumask.h>]. Some examples follow.
In this example, there are 64 cpus in the system but cpus 32-63 exceed
the kernel max which is limited to 0..31 by the NR_CPUS config option
being 32. Note also that cpus 2 and 4-31 are not online but could be
brought online as they are both present and possible.
kernel_max: 31
offline: 2,4-31,32-63
online: 0-1,3
possible: 0-31
present: 0-31
In this example, the NR_CPUS config option is 128, but the kernel was
started with possible_cpus=144. There are 4 cpus in the system and cpu2
was manually taken offline (and is the only cpu that can be brought
online.)
kernel_max: 127
offline: 2,4-127,128-143
online: 0-1,3
possible: 0-127
present: 0-3
See cpu-hotplug.txt for the possible_cpus=NUM kernel start parameter
as well as more information on the various cpumask's.

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@ -13,9 +13,9 @@
3.6 Constraints
3.7 Example
4 DRIVER DEVELOPER NOTES
4 DMAENGINE DRIVER DEVELOPER NOTES
4.1 Conformance points
4.2 "My application needs finer control of hardware channels"
4.2 "My application needs exclusive control of hardware channels"
5 SOURCE
@ -150,6 +150,7 @@ ops_run_* and ops_complete_* routines in drivers/md/raid5.c for more
implementation examples.
4 DRIVER DEVELOPMENT NOTES
4.1 Conformance points:
There are a few conformance points required in dmaengine drivers to
accommodate assumptions made by applications using the async_tx API:
@ -158,58 +159,49 @@ accommodate assumptions made by applications using the async_tx API:
3/ Use async_tx_run_dependencies() in the descriptor clean up path to
handle submission of dependent operations
4.2 "My application needs finer control of hardware channels"
This requirement seems to arise from cases where a DMA engine driver is
trying to support device-to-memory DMA. The dmaengine and async_tx
implementations were designed for offloading memory-to-memory
operations; however, there are some capabilities of the dmaengine layer
that can be used for platform-specific channel management.
Platform-specific constraints can be handled by registering the
application as a 'dma_client' and implementing a 'dma_event_callback' to
apply a filter to the available channels in the system. Before showing
how to implement a custom dma_event callback some background of
dmaengine's client support is required.
4.2 "My application needs exclusive control of hardware channels"
Primarily this requirement arises from cases where a DMA engine driver
is being used to support device-to-memory operations. A channel that is
performing these operations cannot, for many platform specific reasons,
be shared. For these cases the dma_request_channel() interface is
provided.
The following routines in dmaengine support multiple clients requesting
use of a channel:
- dma_async_client_register(struct dma_client *client)
- dma_async_client_chan_request(struct dma_client *client)
The interface is:
struct dma_chan *dma_request_channel(dma_cap_mask_t mask,
dma_filter_fn filter_fn,
void *filter_param);
dma_async_client_register takes a pointer to an initialized dma_client
structure. It expects that the 'event_callback' and 'cap_mask' fields
are already initialized.
Where dma_filter_fn is defined as:
typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param);
dma_async_client_chan_request triggers dmaengine to notify the client of
all channels that satisfy the capability mask. It is up to the client's
event_callback routine to track how many channels the client needs and
how many it is currently using. The dma_event_callback routine returns a
dma_state_client code to let dmaengine know the status of the
allocation.
When the optional 'filter_fn' parameter is set to NULL
dma_request_channel simply returns the first channel that satisfies the
capability mask. Otherwise, when the mask parameter is insufficient for
specifying the necessary channel, the filter_fn routine can be used to
disposition the available channels in the system. The filter_fn routine
is called once for each free channel in the system. Upon seeing a
suitable channel filter_fn returns DMA_ACK which flags that channel to
be the return value from dma_request_channel. A channel allocated via
this interface is exclusive to the caller, until dma_release_channel()
is called.
Below is the example of how to extend this functionality for
platform-specific filtering of the available channels beyond the
standard capability mask:
The DMA_PRIVATE capability flag is used to tag dma devices that should
not be used by the general-purpose allocator. It can be set at
initialization time if it is known that a channel will always be
private. Alternatively, it is set when dma_request_channel() finds an
unused "public" channel.
static enum dma_state_client
my_dma_client_callback(struct dma_client *client,
struct dma_chan *chan, enum dma_state state)
{
struct dma_device *dma_dev;
struct my_platform_specific_dma *plat_dma_dev;
dma_dev = chan->device;
plat_dma_dev = container_of(dma_dev,
struct my_platform_specific_dma,
dma_dev);
if (!plat_dma_dev->platform_specific_capability)
return DMA_DUP;
. . .
}
A couple caveats to note when implementing a driver and consumer:
1/ Once a channel has been privately allocated it will no longer be
considered by the general-purpose allocator even after a call to
dma_release_channel().
2/ Since capabilities are specified at the device level a dma_device
with multiple channels will either have all channels public, or all
channels private.
5 SOURCE
include/linux/dmaengine.h: core header file for DMA drivers and clients
include/linux/dmaengine.h: core header file for DMA drivers and api users
drivers/dma/dmaengine.c: offload engine channel management routines
drivers/dma/: location for offload engine drivers
include/linux/async_tx.h: core header file for the async_tx api

4
Documentation/dell_rbu.txt
View File

@ -81,8 +81,8 @@ Until this step is completed the driver cannot be unloaded.
Also echoing either mono ,packet or init in to image_type will free up the
memory allocated by the driver.
If an user by accident executes steps 1 and 3 above without executing step 2;
it will make the /sys/class/firmware/dell_rbu/ entries to disappear.
If a user by accident executes steps 1 and 3 above without executing step 2;
it will make the /sys/class/firmware/dell_rbu/ entries disappear.
The entries can be recreated by doing the following
echo init > /sys/devices/platform/dell_rbu/image_type
NOTE: echoing init in image_type does not change it original value.

6
Documentation/development-process/4.Coding
View File

@ -375,10 +375,10 @@ say, this can be a large job, so it is best to be sure that the
justification is solid.
When making an incompatible API change, one should, whenever possible,
ensure that code which has not been updated is caught by the compiler.
ensure that code which has not been updated is caught by the compiler.
This will help you to be sure that you have found all in-tree uses of that
interface. It will also alert developers of out-of-tree code that there is
a change that they need to respond to. Supporting out-of-tree code is not
something that kernel developers need to be worried about, but we also do
not have to make life harder for out-of-tree developers than it it needs to
be.
not have to make life harder for out-of-tree developers than it needs to
be.

1
Documentation/dmaengine.txt Normal file
View File

@ -0,0 +1 @@
See Documentation/crypto/async-tx-api.txt

69
Documentation/dvb/technisat.txt Normal file
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@ -0,0 +1,69 @@
How to set up the Technisat devices
===================================
1) Find out what device you have
================================
First start your linux box with a shipped kernel:
lspci -vvv for a PCI device (lsusb -vvv for an USB device) will show you for example:
02:0b.0 Network controller: Techsan Electronics Co Ltd B2C2 FlexCopII DVB chip / Technisat SkyStar2 DVB card (rev 02)
dmesg | grep frontend may show you for example:
DVB: registering frontend 0 (Conexant CX24123/CX24109)...
2) Kernel compilation:
======================
If the Technisat is the only TV device in your box get rid of unnecessary modules and check this one:
"Multimedia devices" => "Customise analog and hybrid tuner modules to build"
In this directory uncheck every driver which is activated there.
Then please activate:
2a) Main module part:
a.)"Multimedia devices" => "DVB/ATSC adapters" => "Technisat/B2C2 FlexcopII(b) and FlexCopIII adapters"
b.)"Multimedia devices" => "DVB/ATSC adapters" => "Technisat/B2C2 FlexcopII(b) and FlexCopIII adapters" => "Technisat/B2C2 Air/Sky/Cable2PC PCI" in case of a PCI card OR
c.)"Multimedia devices" => "DVB/ATSC adapters" => "Technisat/B2C2 FlexcopII(b) and FlexCopIII adapters" => "Technisat/B2C2 Air/Sky/Cable2PC USB" in case of an USB 1.1 adapter
d.)"Multimedia devices" => "DVB/ATSC adapters" => "Technisat/B2C2 FlexcopII(b) and FlexCopIII adapters" => "Enable debug for the B2C2 FlexCop drivers"
Notice: d.) is helpful for troubleshooting
2b) Frontend module part:
1.) Revision 2.3:
a.)"Multimedia devices" => "Customise DVB frontends" => "Customise the frontend modules to build"
b.)"Multimedia devices" => "Customise DVB frontends" => "Zarlink VP310/MT312/ZL10313 based"
2.) Revision 2.6:
a.)"Multimedia devices" => "Customise DVB frontends" => "Customise the frontend modules to build"
b.)"Multimedia devices" => "Customise DVB frontends" => "ST STV0299 based"
3.) Revision 2.7:
a.)"Multimedia devices" => "Customise DVB frontends" => "Customise the frontend modules to build"
b.)"Multimedia devices" => "Customise DVB frontends" => "Samsung S5H1420 based"
c.)"Multimedia devices" => "Customise DVB frontends" => "Integrant ITD1000 Zero IF tuner for DVB-S/DSS"
d.)"Multimedia devices" => "Customise DVB frontends" => "ISL6421 SEC controller"
4.) Revision 2.8:
a.)"Multimedia devices" => "Customise DVB frontends" => "Customise the frontend modules to build"
b.)"Multimedia devices" => "Customise DVB frontends" => "Conexant CX24113/CX24128 tuner for DVB-S/DSS"
c.)"Multimedia devices" => "Customise DVB frontends" => "Conexant CX24123 based"
d.)"Multimedia devices" => "Customise DVB frontends" => "ISL6421 SEC controller"
5.) DVB-T card:
a.)"Multimedia devices" => "Customise DVB frontends" => "Customise the frontend modules to build"
b.)"Multimedia devices" => "Customise DVB frontends" => "Zarlink MT352 based"
6.) DVB-C card:
a.)"Multimedia devices" => "Customise DVB frontends" => "Customise the frontend modules to build"
b.)"Multimedia devices" => "Customise DVB frontends" => "ST STV0297 based"
7.) ATSC card 1st generation:
a.)"Multimedia devices" => "Customise DVB frontends" => "Customise the frontend modules to build"
b.)"Multimedia devices" => "Customise DVB frontends" => "Broadcom BCM3510"
8.) ATSC card 2nd generation:
a.)"Multimedia devices" => "Customise DVB frontends" => "Customise the frontend modules to build"
b.)"Multimedia devices" => "Customise DVB frontends" => "NxtWave Communications NXT2002/NXT2004 based"
c.)"Multimedia devices" => "Customise DVB frontends" => "LG Electronics LGDT3302/LGDT3303 based"
Author: Uwe Bugla <uwe.bugla@gmx.de> December 2008

92
Documentation/fb/pxafb.txt
View File

@ -5,9 +5,13 @@ The driver supports the following options, either via
options=<OPTIONS> when modular or video=pxafb:<OPTIONS> when built in.
For example:
modprobe pxafb options=mode:640x480-8,passive
modprobe pxafb options=vmem:2M,mode:640x480-8,passive
or on the kernel command line
video=pxafb:mode:640x480-8,passive
video=pxafb:vmem:2M,mode:640x480-8,passive
vmem: VIDEO_MEM_SIZE
Amount of video memory to allocate (can be suffixed with K or M
for kilobytes or megabytes)
mode:XRESxYRES[-BPP]
XRES == LCCR1_PPL + 1
@ -52,3 +56,87 @@ outputen:POLARITY
pixclockpol:POLARITY
pixel clock polarity
0 => falling edge, 1 => rising edge
Overlay Support for PXA27x and later LCD controllers
====================================================
PXA27x and later processors support overlay1 and overlay2 on-top of the
base framebuffer (although under-neath the base is also possible). They
support palette and no-palette RGB formats, as well as YUV formats (only
available on overlay2). These overlays have dedicated DMA channels and
behave in a similar way as a framebuffer.
However, there are some differences between these overlay framebuffers
and normal framebuffers, as listed below:
1. overlay can start at a 32-bit word aligned position within the base
framebuffer, which means they have a start (x, y). This information
is encoded into var->nonstd (no, var->xoffset and var->yoffset are
not for such purpose).
2. overlay framebuffer is allocated dynamically according to specified
'struct fb_var_screeninfo', the amount is decided by:
var->xres_virtual * var->yres_virtual * bpp
bpp = 16 -- for RGB565 or RGBT555
= 24 -- for YUV444 packed
= 24 -- for YUV444 planar
= 16 -- for YUV422 planar (1 pixel = 1 Y + 1/2 Cb + 1/2 Cr)
= 12 -- for YUV420 planar (1 pixel = 1 Y + 1/4 Cb + 1/4 Cr)
NOTE:
a. overlay does not support panning in x-direction, thus
var->xres_virtual will always be equal to var->xres
b. line length of overlay(s) must be on a 32-bit word boundary,
for YUV planar modes, it is a requirement for the component
with minimum bits per pixel, e.g. for YUV420, Cr component
for one pixel is actually 2-bits, it means the line length
should be a multiple of 16-pixels
c. starting horizontal position (XPOS) should start on a 32-bit
word boundary, otherwise the fb_check_var() will just fail.
d. the rectangle of the overlay should be within the base plane,
otherwise fail
Applications should follow the sequence below to operate an overlay
framebuffer:
a. open("/dev/fb[1-2]", ...)
b. ioctl(fd, FBIOGET_VSCREENINFO, ...)
c. modify 'var' with desired parameters:
1) var->xres and var->yres
2) larger var->yres_virtual if more memory is required,
usually for double-buffering
3) var->nonstd for starting (x, y) and color format
4) var->{red, green, blue, transp} if RGB mode is to be used
d. ioctl(fd, FBIOPUT_VSCREENINFO, ...)
e. ioctl(fd, FBIOGET_FSCREENINFO, ...)
f. mmap
g. ...
3. for YUV planar formats, these are actually not supported within the
framebuffer framework, application has to take care of the offsets
and lengths of each component within the framebuffer.
4. var->nonstd is used to pass starting (x, y) position and color format,
the detailed bit fields are shown below:
31 23 20 10 0
+-----------------+---+----------+----------+
| ... unused ... |FOR| XPOS | YPOS |
+-----------------+---+----------+----------+
FOR - color format, as defined by OVERLAY_FORMAT_* in pxafb.h
0 - RGB
1 - YUV444 PACKED
2 - YUV444 PLANAR
3 - YUV422 PLANAR
4 - YUR420 PLANAR
XPOS - starting horizontal position
YPOS - starting vertical position

29
Documentation/feature-removal-schedule.txt
View File

@ -310,17 +310,28 @@ Who: Krzysztof Piotr Oledzki <ole@ans.pl>
---------------------------
What: ide-scsi (BLK_DEV_IDESCSI)
When: 2.6.29
Why: The 2.6 kernel supports direct writing to ide CD drives, which
eliminates the need for ide-scsi. The new method is more
efficient in every way.
Who: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
---------------------------
What: i2c_attach_client(), i2c_detach_client(), i2c_driver->detach_client()
When: 2.6.29 (ideally) or 2.6.30 (more likely)
Why: Deprecated by the new (standard) device driver binding model. Use
i2c_driver->probe() and ->remove() instead.
Who: Jean Delvare <khali@linux-fr.org>
---------------------------
What: fscher and fscpos drivers
When: June 2009
Why: Deprecated by the new fschmd driver.
Who: Hans de Goede <hdegoede@redhat.com>
Jean Delvare <khali@linux-fr.org>
---------------------------
What: SELinux "compat_net" functionality
When: 2.6.30 at the earliest
Why: In 2.6.18 the Secmark concept was introduced to replace the "compat_net"
network access control functionality of SELinux. Secmark offers both
better performance and greater flexibility than the "compat_net"
mechanism. Now that the major Linux distributions have moved to
Secmark, it is time to deprecate the older mechanism and start the
process of removing the old code.
Who: Paul Moore <paul.moore@hp.com>

12
Documentation/filesystems/Locking
View File

@ -97,8 +97,8 @@ prototypes:
void (*put_super) (struct super_block *);
void (*write_super) (struct super_block *);
int (*sync_fs)(struct super_block *sb, int wait);
void (*write_super_lockfs) (struct super_block *);
void (*unlockfs) (struct super_block *);
int (*freeze_fs) (struct super_block *);
int (*unfreeze_fs) (struct super_block *);
int (*statfs) (struct dentry *, struct kstatfs *);
int (*remount_fs) (struct super_block *, int *, char *);
void (*clear_inode) (struct inode *);
@ -119,8 +119,8 @@ delete_inode: no
put_super: yes yes no
write_super: no yes read
sync_fs: no no read
write_super_lockfs: ?
unlockfs: ?
freeze_fs: ?
unfreeze_fs: ?
statfs: no no no
remount_fs: yes yes maybe (see below)
clear_inode: no
@ -394,11 +394,10 @@ prototypes:
unsigned long (*get_unmapped_area)(struct file *, unsigned long,
unsigned long, unsigned long, unsigned long);
int (*check_flags)(int);
int (*dir_notify)(struct file *, unsigned long);
};
locking rules:
All except ->poll() may block.
All may block.
BKL
llseek: no (see below)
read: no
@ -424,7 +423,6 @@ sendfile: no
sendpage: no
get_unmapped_area: no
check_flags: no
dir_notify: no
->llseek() locking has moved from llseek to the individual llseek
implementations. If your fs is not using generic_file_llseek, you

91
Documentation/filesystems/btrfs.txt Normal file
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@ -0,0 +1,91 @@
BTRFS
=====
Btrfs is a new copy on write filesystem for Linux aimed at
implementing advanced features while focusing on fault tolerance,
repair and easy administration. Initially developed by Oracle, Btrfs
is licensed under the GPL and open for contribution from anyone.
Linux has a wealth of filesystems to choose from, but we are facing a
number of challenges with scaling to the large storage subsystems that
are becoming common in today's data centers. Filesystems need to scale
in their ability to address and manage large storage, and also in
their ability to detect, repair and tolerate errors in the data stored
on disk. Btrfs is under heavy development, and is not suitable for
any uses other than benchmarking and review. The Btrfs disk format is
not yet finalized.
The main Btrfs features include:
* Extent based file storage (2^64 max file size)
* Space efficient packing of small files
* Space efficient indexed directories
* Dynamic inode allocation
* Writable snapshots
* Subvolumes (separate internal filesystem roots)
* Object level mirroring and striping
* Checksums on data and metadata (multiple algorithms available)
* Compression
* Integrated multiple device support, with several raid algorithms
* Online filesystem check (not yet implemented)
* Very fast offline filesystem check
* Efficient incremental backup and FS mirroring (not yet implemented)
* Online filesystem defragmentation
MAILING LIST
============
There is a Btrfs mailing list hosted on vger.kernel.org. You can
find details on how to subscribe here:
http://vger.kernel.org/vger-lists.html#linux-btrfs
Mailing list archives are available from gmane:
http://dir.gmane.org/gmane.comp.file-systems.btrfs
IRC
===
Discussion of Btrfs also occurs on the #btrfs channel of the Freenode
IRC network.
UTILITIES
=========
Userspace tools for creating and manipulating Btrfs file systems are
available from the git repository at the following location:
http://git.kernel.org/?p=linux/kernel/git/mason/btrfs-progs-unstable.git
git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-progs-unstable.git
These include the following tools:
mkfs.btrfs: create a filesystem
btrfsctl: control program to create snapshots and subvolumes:
mount /dev/sda2 /mnt
btrfsctl -s new_subvol_name /mnt
btrfsctl -s snapshot_of_default /mnt/default
btrfsctl -s snapshot_of_new_subvol /mnt/new_subvol_name
btrfsctl -s snapshot_of_a_snapshot /mnt/snapshot_of_new_subvol
ls /mnt
default snapshot_of_a_snapshot snapshot_of_new_subvol
new_subvol_name snapshot_of_default
Snapshots and subvolumes cannot be deleted right now, but you can
rm -rf all the files and directories inside them.
btrfsck: do a limited check of the FS extent trees.
btrfs-debug-tree: print all of the FS metadata in text form. Example:
btrfs-debug-tree /dev/sda2 >& big_output_file

132
Documentation/filesystems/devpts.txt Normal file
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@ -0,0 +1,132 @@
To support containers, we now allow multiple instances of devpts filesystem,
such that indices of ptys allocated in one instance are independent of indices
allocated in other instances of devpts.
To preserve backward compatibility, this support for multiple instances is
enabled only if:
- CONFIG_DEVPTS_MULTIPLE_INSTANCES=y, and
- '-o newinstance' mount option is specified while mounting devpts
IOW, devpts now supports both single-instance and multi-instance semantics.
If CONFIG_DEVPTS_MULTIPLE_INSTANCES=n, there is no change in behavior and
this referred to as the "legacy" mode. In this mode, the new mount options
(-o newinstance and -o ptmxmode) will be ignored with a 'bogus option' message
on console.
If CONFIG_DEVPTS_MULTIPLE_INSTANCES=y and devpts is mounted without the
'newinstance' option (as in current start-up scripts) the new mount binds
to the initial kernel mount of devpts. This mode is referred to as the
'single-instance' mode and the current, single-instance semantics are
preserved, i.e PTYs are common across the system.
The only difference between this single-instance mode and the legacy mode
is the presence of new, '/dev/pts/ptmx' node with permissions 0000, which
can safely be ignored.
If CONFIG_DEVPTS_MULTIPLE_INSTANCES=y and 'newinstance' option is specified,
the mount is considered to be in the multi-instance mode and a new instance
of the devpts fs is created. Any ptys created in this instance are independent
of ptys in other instances of devpts. Like in the single-instance mode, the
/dev/pts/ptmx node is present. To effectively use the multi-instance mode,
open of /dev/ptmx must be a redirected to '/dev/pts/ptmx' using a symlink or
bind-mount.
Eg: A container startup script could do the following:
$ chmod 0666 /dev/pts/ptmx
$ rm /dev/ptmx
$ ln -s pts/ptmx /dev/ptmx
$ ns_exec -cm /bin/bash
# We are now in new container
$ umount /dev/pts
$ mount -t devpts -o newinstance lxcpts /dev/pts
$ sshd -p 1234
where 'ns_exec -cm /bin/bash' calls clone() with CLONE_NEWNS flag and execs
/bin/bash in the child process. A pty created by the sshd is not visible in
the original mount of /dev/pts.
User-space changes
------------------
In multi-instance mode (i.e '-o newinstance' mount option is specified at least
once), following user-space issues should be noted.
1. If -o newinstance mount option is never used, /dev/pts/ptmx can be ignored
and no change is needed to system-startup scripts.
2. To effectively use multi-instance mode (i.e -o newinstance is specified)
administrators or startup scripts should "redirect" open of /dev/ptmx to
/dev/pts/ptmx using either a bind mount or symlink.
$ mount -t devpts -o newinstance devpts /dev/pts
followed by either
$ rm /dev/ptmx
$ ln -s pts/ptmx /dev/ptmx
$ chmod 666 /dev/pts/ptmx
or
$ mount -o bind /dev/pts/ptmx /dev/ptmx
3. The '/dev/ptmx -> pts/ptmx' symlink is the preferred method since it
enables better error-reporting and treats both single-instance and
multi-instance mounts similarly.
But this method requires that system-startup scripts set the mode of
/dev/pts/ptmx correctly (default mode is 0000). The scripts can set the
mode by, either
- adding ptmxmode mount option to devpts entry in /etc/fstab, or
- using 'chmod 0666 /dev/pts/ptmx'
4. If multi-instance mode mount is needed for containers, but the system
startup scripts have not yet been updated, container-startup scripts
should bind mount /dev/ptmx to /dev/pts/ptmx to avoid breaking single-
instance mounts.
Or, in general, container-startup scripts should use:
mount -t devpts -o newinstance -o ptmxmode=0666 devpts /dev/pts
if [ ! -L /dev/ptmx ]; then
mount -o bind /dev/pts/ptmx /dev/ptmx
fi
When all devpts mounts are multi-instance, /dev/ptmx can permanently be
a symlink to pts/ptmx and the bind mount can be ignored.
5. A multi-instance mount that is not accompanied by the /dev/ptmx to
/dev/pts/ptmx redirection would result in an unusable/unreachable pty.
mount -t devpts -o newinstance lxcpts /dev/pts
immediately followed by:
open("/dev/ptmx")
would create a pty, say /dev/pts/7, in the initial kernel mount.
But /dev/pts/7 would be invisible in the new mount.
6. The permissions for /dev/pts/ptmx node should be specified when mounting
/dev/pts, using the '-o ptmxmode=%o' mount option (default is 0000).
mount -t devpts -o newinstance -o ptmxmode=0644 devpts /dev/pts
The permissions can be later be changed as usual with 'chmod'.
chmod 666 /dev/pts/ptmx
7. A mount of devpts without the 'newinstance' option results in binding to
initial kernel mount. This behavior while preserving legacy semantics,
does not provide strict isolation in a container environment. i.e by
mounting devpts without the 'newinstance' option, a container could
get visibility into the 'host' or root container's devpts.
To workaround this and have strict isolation, all mounts of devpts,
including the mount in the root container, should use the newinstance
option.

85
Documentation/filesystems/ext4.txt
View File

@ -58,13 +58,22 @@ Note: More extensive information for getting started with ext4 can be
# mount -t ext4 /dev/hda1 /wherever
- When comparing performance with other filesystems, remember that
ext3/4 by default offers higher data integrity guarantees than most.
So when comparing with a metadata-only journalling filesystem, such
as ext3, use `mount -o data=writeback'. And you might as well use
`mount -o nobh' too along with it. Making the journal larger than
the mke2fs default often helps performance with metadata-intensive
workloads.
- When comparing performance with other filesystems, it's always
important to try multiple workloads; very often a subtle change in a
workload parameter can completely change the ranking of which
filesystems do well compared to others. When comparing versus ext3,
note that ext4 enables write barriers by default, while ext3 does
not enable write barriers by default. So it is useful to use
explicitly specify whether barriers are enabled or not when via the
'-o barriers=[0|1]' mount option for both ext3 and ext4 filesystems
for a fair comparison. When tuning ext3 for best benchmark numbers,
it is often worthwhile to try changing the data journaling mode; '-o
data=writeback,nobh' can be faster for some workloads. (Note
however that running mounted with data=writeback can potentially
leave stale data exposed in recently written files in case of an
unclean shutdown, which could be a security exposure in some
situations.) Configuring the filesystem with a large journal can
also be helpful for metadata-intensive workloads.
2. Features
===========
@ -74,7 +83,7 @@ Note: More extensive information for getting started with ext4 can be
* ability to use filesystems > 16TB (e2fsprogs support not available yet)
* extent format reduces metadata overhead (RAM, IO for access, transactions)
* extent format more robust in face of on-disk corruption due to magics,
* internal redunancy in tree
* internal redundancy in tree
* improved file allocation (multi-block alloc)
* fix 32000 subdirectory limit
* nsec timestamps for mtime, atime, ctime, create time
@ -116,10 +125,11 @@ grouping of bitmaps and inode tables. Some test results available here:
When mounting an ext4 filesystem, the following option are accepted:
(*) == default
extents (*) ext4 will use extents to address file data. The
file system will no longer be mountable by ext3.
noextents ext4 will not use extents for newly created files
ro Mount filesystem read only. Note that ext4 will
replay the journal (and thus write to the
partition) even when mounted "read only". The
mount options "ro,noload" can be used to prevent
writes to the filesystem.
journal_checksum Enable checksumming of the journal transactions.
This will allow the recovery code in e2fsck and the
@ -134,17 +144,17 @@ journal_async_commit Commit block can be written to disk without waiting
journal=update Update the ext4 file system's journal to the current
format.
journal=inum When a journal already exists, this option is ignored.
Otherwise, it specifies the number of the inode which
will represent the ext4 file system's journal file.
journal_dev=devnum When the external journal device's major/minor numbers
have changed, this option allows the user to specify
the new journal location. The journal device is
identified through its new major/minor numbers encoded
in devnum.
noload Don't load the journal on mounting.
noload Don't load the journal on mounting. Note that
if the filesystem was not unmounted cleanly,
skipping the journal replay will lead to the
filesystem containing inconsistencies that can
lead to any number of problems.
data=journal All data are committed into the journal prior to being
written into the main file system.
@ -219,9 +229,12 @@ minixdf Make 'df' act like Minix.
debug Extra debugging information is sent to syslog.
errors=remount-ro(*) Remount the filesystem read-only on an error.
errors=remount-ro Remount the filesystem read-only on an error.
errors=continue Keep going on a filesystem error.
errors=panic Panic and halt the machine if an error occurs.
(These mount options override the errors behavior
specified in the superblock, which can be configured
using tune2fs)
data_err=ignore(*) Just print an error message if an error occurs
in a file data buffer in ordered mode.
@ -261,6 +274,42 @@ delalloc (*) Deferring block allocation until write-out time.
nodelalloc Disable delayed allocation. Blocks are allocation
when data is copied from user to page cache.
max_batch_time=usec Maximum amount of time ext4 should wait for
additional filesystem operations to be batch
together with a synchronous write operation.
Since a synchronous write operation is going to
force a commit and then a wait for the I/O
complete, it doesn't cost much, and can be a
huge throughput win, we wait for a small amount
of time to see if any other transactions can
piggyback on the synchronous write. The
algorithm used is designed to automatically tune
for the speed of the disk, by measuring the
amount of time (on average) that it takes to
finish committing a transaction. Call this time
the "commit time". If the time that the
transactoin has been running is less than the
commit time, ext4 will try sleeping for the
commit time to see if other operations will join
the transaction. The commit time is capped by
the max_batch_time, which defaults to 15000us
(15ms). This optimization can be turned off
entirely by setting max_batch_time to 0.
min_batch_time=usec This parameter sets the commit time (as
described above) to be at least min_batch_time.
It defaults to zero microseconds. Increasing
this parameter may improve the throughput of
multi-threaded, synchronous workloads on very
fast disks, at the cost of increasing latency.
journal_ioprio=prio The I/O priority (from 0 to 7, where 0 is the
highest priorty) which should be used for I/O
operations submitted by kjournald2 during a
commit operation. This defaults to 3, which is
a slightly higher priority than the default I/O
priority.
Data Mode
=========
There are 3 different data modes:

6
Documentation/filesystems/files.txt
View File

@ -76,13 +76,13 @@ the fdtable structure -
5. Handling of the file structures is special. Since the look-up
of the fd (fget()/fget_light()) are lock-free, it is possible
that look-up may race with the last put() operation on the
file structure. This is avoided using atomic_inc_not_zero()
file structure. This is avoided using atomic_long_inc_not_zero()
on ->f_count :
rcu_read_lock();
file = fcheck_files(files, fd);
if (file) {
if (atomic_inc_not_zero(&file->f_count))
if (atomic_long_inc_not_zero(&file->f_count))
*fput_needed = 1;
else
/* Didn't get the reference, someone's freed */
@ -92,7 +92,7 @@ the fdtable structure -
....
return file;
atomic_inc_not_zero() detects if refcounts is already zero or
atomic_long_inc_not_zero() detects if refcounts is already zero or
goes to zero during increment. If it does, we fail
fget()/fget_light().

3
Documentation/filesystems/ocfs2.txt
View File

@ -31,7 +31,6 @@ Features which OCFS2 does not support yet:
- quotas
- Directory change notification (F_NOTIFY)
- Distributed Caching (F_SETLEASE/F_GETLEASE/break_lease)
- POSIX ACLs
Mount options
=============
@ -79,3 +78,5 @@ inode64 Indicates that Ocfs2 is allowed to create inodes at
bits of significance.
user_xattr (*) Enables Extended User Attributes.
nouser_xattr Disables Extended User Attributes.
acl Enables POSIX Access Control Lists support.
noacl (*) Disables POSIX Access Control Lists support.

27
Documentation/filesystems/proc.txt
View File

@ -140,6 +140,7 @@ Table 1-1: Process specific entries in /proc
statm Process memory status information
status Process status in human readable form
wchan If CONFIG_KALLSYMS is set, a pre-decoded wchan
stack Report full stack trace, enable via CONFIG_STACKTRACE
smaps Extension based on maps, the rss size for each mapped file
..............................................................................
@ -1385,6 +1386,15 @@ swapcache reclaim. Decreasing vfs_cache_pressure causes the kernel to prefer
to retain dentry and inode caches. Increasing vfs_cache_pressure beyond 100
causes the kernel to prefer to reclaim dentries and inodes.
dirty_background_bytes
----------------------
Contains the amount of dirty memory at which the pdflush background writeback
daemon will start writeback.
If dirty_background_bytes is written, dirty_background_ratio becomes a function
of its value (dirty_background_bytes / the amount of dirtyable system memory).
dirty_background_ratio
----------------------
@ -1393,14 +1403,29 @@ pages + file cache, not including locked pages and HugePages), the number of
pages at which the pdflush background writeback daemon will start writing out
dirty data.
If dirty_background_ratio is written, dirty_background_bytes becomes a function
of its value (dirty_background_ratio * the amount of dirtyable system memory).
dirty_bytes
-----------
Contains the amount of dirty memory at which a process generating disk writes
will itself start writeback.
If dirty_bytes is written, dirty_ratio becomes a function of its value
(dirty_bytes / the amount of dirtyable system memory).
dirty_ratio
-----------------
-----------
Contains, as a percentage of the dirtyable system memory (free pages + mapped
pages + file cache, not including locked pages and HugePages), the number of
pages at which a process which is generating disk writes will itself start
writing out dirty data.
If dirty_ratio is written, dirty_bytes becomes a function of its value
(dirty_ratio * the amount of dirtyable system memory).
dirty_writeback_centisecs
-------------------------

225
Documentation/filesystems/squashfs.txt Normal file
View File

@ -0,0 +1,225 @@
SQUASHFS 4.0 FILESYSTEM
=======================
Squashfs is a compressed read-only filesystem for Linux.
It uses zlib compression to compress files, inodes and directories.
Inodes in the system are very small and all blocks are packed to minimise
data overhead. Block sizes greater than 4K are supported up to a maximum
of 1Mbytes (default block size 128K).
Squashfs is intended for general read-only filesystem use, for archival
use (i.e. in cases where a .tar.gz file may be used), and in constrained
block device/memory systems (e.g. embedded systems) where low overhead is
needed.
Mailing list: squashfs-devel@lists.sourceforge.net
Web site: www.squashfs.org
1. FILESYSTEM FEATURES
----------------------
Squashfs filesystem features versus Cramfs:
Squashfs Cramfs
Max filesystem size: 2^64 16 MiB
Max file size: ~ 2 TiB 16 MiB
Max files: unlimited unlimited
Max directories: unlimited unlimited
Max entries per directory: unlimited unlimited
Max block size: 1 MiB 4 KiB
Metadata compression: yes no
Directory indexes: yes no
Sparse file support: yes no
Tail-end packing (fragments): yes no
Exportable (NFS etc.): yes no
Hard link support: yes no
"." and ".." in readdir: yes no
Real inode numbers: yes no
32-bit uids/gids: yes no
File creation time: yes no
Xattr and ACL support: no no
Squashfs compresses data, inodes and directories. In addition, inode and
directory data are highly compacted, and packed on byte boundaries. Each
compressed inode is on average 8 bytes in length (the exact length varies on
file type, i.e. regular file, directory, symbolic link, and block/char device
inodes have different sizes).
2. USING SQUASHFS
-----------------
As squashfs is a read-only filesystem, the mksquashfs program must be used to
create populated squashfs filesystems. This and other squashfs utilities
can be obtained from http://www.squashfs.org. Usage instructions can be
obtained from this site also.
3. SQUASHFS FILESYSTEM DESIGN
-----------------------------
A squashfs filesystem consists of seven parts, packed together on a byte
alignment:
---------------
| superblock |
|---------------|
| datablocks |
| & fragments |
|---------------|
| inode table |
|---------------|
| directory |
| table |
|---------------|
| fragment |
| table |
|---------------|
| export |
| table |
|---------------|
| uid/gid |
| lookup table |
---------------
Compressed data blocks are written to the filesystem as files are read from
the source directory, and checked for duplicates. Once all file data has been
written the completed inode, directory, fragment, export and uid/gid lookup
tables are written.
3.1 Inodes
----------
Metadata (inodes and directories) are compressed in 8Kbyte blocks. Each
compressed block is prefixed by a two byte length, the top bit is set if the
block is uncompressed. A block will be uncompressed if the -noI option is set,
or if the compressed block was larger than the uncompressed block.
Inodes are packed into the metadata blocks, and are not aligned to block
boundaries, therefore inodes overlap compressed blocks. Inodes are identified
by a 48-bit number which encodes the location of the compressed metadata block
containing the inode, and the byte offset into that block where the inode is
placed (<block, offset>).
To maximise compression there are different inodes for each file type
(regular file, directory, device, etc.), the inode contents and length
varying with the type.
To further maximise compression, two types of regular file inode and
directory inode are defined: inodes optimised for frequently occurring
regular files and directories, and extended types where extra
information has to be stored.
3.2 Directories
---------------
Like inodes, directories are packed into compressed metadata blocks, stored
in a directory table. Directories are accessed using the start address of
the metablock containing the directory and the offset into the
decompressed block (<block, offset>).
Directories are organised in a slightly complex way, and are not simply
a list of file names. The organisation takes advantage of the
fact that (in most cases) the inodes of the files will be in the same
compressed metadata block, and therefore, can share the start block.
Directories are therefore organised in a two level list, a directory
header containing the shared start block value, and a sequence of directory
entries, each of which share the shared start block. A new directory header
is written once/if the inode start block changes. The directory
header/directory entry list is repeated as many times as necessary.
Directories are sorted, and can contain a directory index to speed up
file lookup. Directory indexes store one entry per metablock, each entry
storing the index/filename mapping to the first directory header
in each metadata block. Directories are sorted in alphabetical order,
and at lookup the index is scanned linearly looking for the first filename
alphabetically larger than the filename being looked up. At this point the
location of the metadata block the filename is in has been found.
The general idea of the index is ensure only one metadata block needs to be
decompressed to do a lookup irrespective of the length of the directory.
This scheme has the advantage that it doesn't require extra memory overhead
and doesn't require much extra storage on disk.
3.3 File data
-------------
Regular files consist of a sequence of contiguous compressed blocks, and/or a
compressed fragment block (tail-end packed block). The compressed size
of each datablock is stored in a block list contained within the
file inode.
To speed up access to datablocks when reading 'large' files (256 Mbytes or
larger), the code implements an index cache that caches the mapping from
block index to datablock location on disk.
The index cache allows Squashfs to handle large files (up to 1.75 TiB) while
retaining a simple and space-efficient block list on disk. The cache
is split into slots, caching up to eight 224 GiB files (128 KiB blocks).
Larger files use multiple slots, with 1.75 TiB files using all 8 slots.
The index cache is designed to be memory efficient, and by default uses
16 KiB.
3.4 Fragment lookup table
-------------------------
Regular files can contain a fragment index which is mapped to a fragment
location on disk and compressed size using a fragment lookup table. This
fragment lookup table is itself stored compressed into metadata blocks.
A second index table is used to locate these. This second index table for
speed of access (and because it is small) is read at mount time and cached
in memory.
3.5 Uid/gid lookup table
------------------------
For space efficiency regular files store uid and gid indexes, which are
converted to 32-bit uids/gids using an id look up table. This table is
stored compressed into metadata blocks. A second index table is used to
locate these. This second index table for speed of access (and because it
is small) is read at mount time and cached in memory.
3.6 Export table
----------------
To enable Squashfs filesystems to be exportable (via NFS etc.) filesystems
can optionally (disabled with the -no-exports Mksquashfs option) contain
an inode number to inode disk location lookup table. This is required to
enable Squashfs to map inode numbers passed in filehandles to the inode
location on disk, which is necessary when the export code reinstantiates
expired/flushed inodes.
This table is stored compressed into metadata blocks. A second index table is
used to locate these. This second index table for speed of access (and because
it is small) is read at mount time and cached in memory.
4. TODOS AND OUTSTANDING ISSUES
-------------------------------
4.1 Todo list
-------------
Implement Xattr and ACL support. The Squashfs 4.0 filesystem layout has hooks
for these but the code has not been written. Once the code has been written
the existing layout should not require modification.
4.2 Squashfs internal cache
---------------------------
Blocks in Squashfs are compressed. To avoid repeatedly decompressing
recently accessed data Squashfs uses two small metadata and fragment caches.
The cache is not used for file datablocks, these are decompressed and cached in
the page-cache in the normal way. The cache is used to temporarily cache
fragment and metadata blocks which have been read as a result of a metadata
(i.e. inode or directory) or fragment access. Because metadata and fragments
are packed together into blocks (to gain greater compression) the read of a
particular piece of metadata or fragment will retrieve other metadata/fragments
which have been packed with it, these because of locality-of-reference may be
read in the near future. Temporarily caching them ensures they are available
for near future access without requiring an additional read and decompress.
In the future this internal cache may be replaced with an implementation which
uses the kernel page cache. Because the page cache operates on page sized
units this may introduce additional complexity in terms of locking and
associated race conditions.

3
Documentation/filesystems/ubifs.txt
View File

@ -95,6 +95,9 @@ no_chk_data_crc skip checking of CRCs on data nodes in order to
of this option is that corruption of the contents
of a file can go unnoticed.
chk_data_crc (*) do not skip checking CRCs on data nodes
compr=none override default compressor and set it to "none"
compr=lzo override default compressor and set it to "lzo"
compr=zlib override default compressor and set it to "zlib"
Quick usage instructions

13
Documentation/filesystems/vfs.txt
View File

@ -210,8 +210,8 @@ struct super_operations {
void (*put_super) (struct super_block *);
void (*write_super) (struct super_block *);
int (*sync_fs)(struct super_block *sb, int wait);
void (*write_super_lockfs) (struct super_block *);
void (*unlockfs) (struct super_block *);
int (*freeze_fs) (struct super_block *);
int (*unfreeze_fs) (struct super_block *);
int (*statfs) (struct dentry *, struct kstatfs *);
int (*remount_fs) (struct super_block *, int *, char *);
void (*clear_inode) (struct inode *);
@ -270,11 +270,11 @@ or bottom half).
a superblock. The second parameter indicates whether the method
should wait until the write out has been completed. Optional.
write_super_lockfs: called when VFS is locking a filesystem and
freeze_fs: called when VFS is locking a filesystem and
forcing it into a consistent state. This method is currently
used by the Logical Volume Manager (LVM).
unlockfs: called when VFS is unlocking a filesystem and making it writable
unfreeze_fs: called when VFS is unlocking a filesystem and making it writable
again.
statfs: called when the VFS needs to get filesystem statistics. This
@ -733,7 +733,6 @@ struct file_operations {
ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
int (*check_flags)(int);
int (*dir_notify)(struct file *filp, unsigned long arg);
int (*flock) (struct file *, int, struct file_lock *);
ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, size_t, unsigned int);
ssize_t (*splice_read)(struct file *, struct pipe_inode_info *, size_t, unsigned int);
@ -800,8 +799,6 @@ otherwise noted.
check_flags: called by the fcntl(2) system call for F_SETFL command
dir_notify: called by the fcntl(2) system call for F_NOTIFY command
flock: called by the flock(2) system call
splice_write: called by the VFS to splice data from a pipe to a file. This
@ -931,7 +928,7 @@ manipulate dentries:
d_lookup: look up a dentry given its parent and path name component
It looks up the child of that given name from the dcache
hash table. If it is found, the reference count is incremented
and the dentry is returned. The caller must use d_put()
and the dentry is returned. The caller must use dput()
to free the dentry when it finishes using it.
For further information on dentry locking, please refer to the document

4
Documentation/filesystems/xfs.txt
View File

@ -229,10 +229,6 @@ The following sysctls are available for the XFS filesystem:
ISGID bit is cleared if the irix_sgid_inherit compatibility sysctl
is set.
fs.xfs.restrict_chown (Min: 0 Default: 1 Max: 1)
Controls whether unprivileged users can use chown to "give away"
a file to another user.
fs.xfs.inherit_sync (Min: 0 Default: 1 Max: 1)
Setting this to "1" will cause the "sync" flag set
by the xfs_io(8) chattr command on a directory to be

10
Documentation/hwmon/abituguru-datasheet
View File

@ -74,7 +74,7 @@ a sensor.
Notice that some banks have both a read and a write address this is how the
uGuru determines if a read from or a write to the bank is taking place, thus
when reading you should always use the read address and when writing the
write address. The write address is always one (1) more then the read address.
write address. The write address is always one (1) more than the read address.
uGuru ready
@ -121,7 +121,7 @@ Once all bytes have been read data will hold 0x09, but there is no reason to
test for this. Notice that the number of bytes is bank address dependent see
above and below.
After completing a successfull read it is advised to put the uGuru back in
After completing a successful read it is advised to put the uGuru back in
ready mode, so that it is ready for the next read / write cycle. This way
if your program / driver is unloaded and later loaded again the detection
algorithm described above will still work.
@ -141,7 +141,7 @@ don't ask why this is the way it is.
Once DATA holds 0x01 read CMD it should hold 0xAC now.
After completing a successfull write it is advised to put the uGuru back in
After completing a successful write it is advised to put the uGuru back in
ready mode, so that it is ready for the next read / write cycle. This way
if your program / driver is unloaded and later loaded again the detection
algorithm described above will still work.
@ -224,7 +224,7 @@ Bit 3: Beep if alarm (RW)
Bit 4: 1 if alarm cause measured temp is over the warning threshold (R)
Bit 5: 1 if alarm cause measured volt is over the max threshold (R)
Bit 6: 1 if alarm cause measured volt is under the min threshold (R)
Bit 7: Volt sensor: Shutdown if alarm persist for more then 4 seconds (RW)
Bit 7: Volt sensor: Shutdown if alarm persist for more than 4 seconds (RW)
Temp sensor: Shutdown if temp is over the shutdown threshold (RW)
* This bit is only honored/used by the uGuru if a temp sensor is connected
@ -293,7 +293,7 @@ Byte 0:
Alarm behaviour for the selected sensor. A 1 enables the described behaviour.
Bit 0: Give an alarm if measured rpm is under the min threshold (RW)
Bit 3: Beep if alarm (RW)
Bit 7: Shutdown if alarm persist for more then 4 seconds (RW)
Bit 7: Shutdown if alarm persist for more than 4 seconds (RW)
Byte 1:
min threshold (scale as bank 0x26)

19
Documentation/hwmon/adt7470
View File

@ -31,15 +31,11 @@ Each of the measured inputs (temperature, fan speed) has corresponding high/low
limit values. The ADT7470 will signal an ALARM if any measured value exceeds
either limit.
The ADT7470 DOES NOT sample all inputs continuously. A single pin on the
ADT7470 is connected to a multitude of thermal diodes, but the chip must be
instructed explicitly to read the multitude of diodes. If you want to use
automatic fan control mode, you must manually read any of the temperature
sensors or the fan control algorithm will not run. The chip WILL NOT DO THIS
AUTOMATICALLY; this must be done from userspace. This may be a bug in the chip
design, given that many other AD chips take care of this. The driver will not
read the registers more often than once every 5 seconds. Further,
configuration data is only read once per minute.
The ADT7470 samples all inputs continuously. A kernel thread is started up for
the purpose of periodically querying the temperature sensors, thus allowing the
automatic fan pwm control to set the fan speed. The driver will not read the
registers more often than once every 5 seconds. Further, configuration data is
only read once per minute.
Special Features
----------------
@ -72,5 +68,6 @@ pwm#_auto_point2_temp.
Notes
-----
As stated above, the temperature inputs must be read periodically from
userspace in order for the automatic pwm algorithm to run.
The temperature inputs no longer need to be read periodically from userspace in
order for the automatic pwm algorithm to run. This was the case for earlier
versions of the driver.

89
Documentation/hwmon/f71882fg Normal file
View File

@ -0,0 +1,89 @@
Kernel driver f71882fg
======================
Supported chips:
* Fintek F71882FG and F71883FG
Prefix: 'f71882fg'
Addresses scanned: none, address read from Super I/O config space
Datasheet: Available from the Fintek website
* Fintek F71862FG and F71863FG
Prefix: 'f71862fg'
Addresses scanned: none, address read from Super I/O config space
Datasheet: Available from the Fintek website
* Fintek F8000
Prefix: 'f8000'
Addresses scanned: none, address read from Super I/O config space
Datasheet: Not public
Author: Hans de Goede <hdegoede@redhat.com>
Description
-----------
Fintek F718xxFG/F8000 Super I/O chips include complete hardware monitoring
capabilities. They can monitor up to 9 voltages (3 for the F8000), 4 fans and
3 temperature sensors.
These chips also have fan controlling features, using either DC or PWM, in
three different modes (one manual, two automatic).
The driver assumes that no more than one chip is present, which seems
reasonable.
Monitoring
----------
The Voltage, Fan and Temperature Monitoring uses the standard sysfs
interface as documented in sysfs-interface, without any exceptions.
Fan Control
-----------
Both PWM (pulse-width modulation) and DC fan speed control methods are
supported. The right one to use depends on external circuitry on the
motherboard, so the driver assumes that the BIOS set the method
properly.
There are 2 modes to specify the speed of the fan, PWM duty cycle (or DC
voltage) mode, where 0-100% duty cycle (0-100% of 12V) is specified. And RPM
mode where the actual RPM of the fan (as measured) is controlled and the speed
gets specified as 0-100% of the fan#_full_speed file.
Since both modes work in a 0-100% (mapped to 0-255) scale, there isn't a
whole lot of a difference when modifying fan control settings. The only
important difference is that in RPM mode the 0-100% controls the fan speed
between 0-100% of fan#_full_speed. It is assumed that if the BIOS programs
RPM mode, it will also set fan#_full_speed properly, if it does not then
fan control will not work properly, unless you set a sane fan#_full_speed
value yourself.
Switching between these modes requires re-initializing a whole bunch of
registers, so the mode which the BIOS has set is kept. The mode is
printed when loading the driver.
Three different fan control modes are supported; the mode number is written
to the pwm#_enable file. Note that not all modes are supported on all
chips, and some modes may only be available in RPM / PWM mode on the F8000.
Writing an unsupported mode will result in an invalid parameter error.
* 1: Manual mode
You ask for a specific PWM duty cycle / DC voltage or a specific % of
fan#_full_speed by writing to the pwm# file. This mode is only
available on the F8000 if the fan channel is in RPM mode.
* 2: Normal auto mode
You can define a number of temperature/fan speed trip points, which % the
fan should run at at this temp and which temp a fan should follow using the
standard sysfs interface. The number and type of trip points is chip
depended, see which files are available in sysfs.
Fan/PWM channel 3 of the F8000 is always in this mode!
* 3: Thermostat mode (Only available on the F8000 when in duty cycle mode)
The fan speed is regulated to keep the temp the fan is mapped to between
temp#_auto_point2_temp and temp#_auto_point3_temp.
Both of the automatic modes require that pwm1 corresponds to fan1, pwm2 to
fan2 and pwm3 to fan3.

20
Documentation/hwmon/it87
View File

@ -26,6 +26,10 @@ Supported chips:
Datasheet: Publicly available at the ITE website
http://www.ite.com.tw/product_info/file/pc/IT8718F_V0.2.zip
http://www.ite.com.tw/product_info/file/pc/IT8718F_V0%203_(for%20C%20version).zip
* IT8720F
Prefix: 'it8720'
Addresses scanned: from Super I/O config space (8 I/O ports)
Datasheet: Not yet publicly available.
* SiS950 [clone of IT8705F]
Prefix: 'it87'
Addresses scanned: from Super I/O config space (8 I/O ports)
@ -71,7 +75,7 @@ Description
-----------
This driver implements support for the IT8705F, IT8712F, IT8716F,
IT8718F, IT8726F and SiS950 chips.
IT8718F, IT8720F, IT8726F and SiS950 chips.
These chips are 'Super I/O chips', supporting floppy disks, infrared ports,
joysticks and other miscellaneous stuff. For hardware monitoring, they
@ -84,19 +88,19 @@ the IT8716F and late IT8712F have 6. They are shared with other functions
though, so the functionality may not be available on a given system.
The driver dumbly assume it is there.
The IT8718F also features VID inputs (up to 8 pins) but the value is
stored in the Super-I/O configuration space. Due to technical limitations,
The IT8718F and IT8720F also features VID inputs (up to 8 pins) but the value
is stored in the Super-I/O configuration space. Due to technical limitations,
this value can currently only be read once at initialization time, so
the driver won't notice and report changes in the VID value. The two
upper VID bits share their pins with voltage inputs (in5 and in6) so you
can't have both on a given board.
The IT8716F, IT8718F and later IT8712F revisions have support for
The IT8716F, IT8718F, IT8720F and later IT8712F revisions have support for
2 additional fans. The additional fans are supported by the driver.
The IT8716F and IT8718F, and late IT8712F and IT8705F also have optional
16-bit tachometer counters for fans 1 to 3. This is better (no more fan
clock divider mess) but not compatible with the older chips and
The IT8716F, IT8718F and IT8720F, and late IT8712F and IT8705F also have
optional 16-bit tachometer counters for fans 1 to 3. This is better (no more
fan clock divider mess) but not compatible with the older chips and
revisions. The 16-bit tachometer mode is enabled by the driver when one
of the above chips is detected.
@ -122,7 +126,7 @@ zero'; this is important for negative voltage measurements. All voltage
inputs can measure voltages between 0 and 4.08 volts, with a resolution of
0.016 volt. The battery voltage in8 does not have limit registers.
The VID lines (IT8712F/IT8716F/IT8718F) encode the core voltage value:
The VID lines (IT8712F/IT8716F/IT8718F/IT8720F) encode the core voltage value:
the voltage level your processor should work with. This is hardcoded by
the mainboard and/or processor itself. It is a value in volts.

12
Documentation/hwmon/lm70
View File

@ -1,9 +1,11 @@
Kernel driver lm70
==================
Supported chip:
Supported chips:
* National Semiconductor LM70
Datasheet: http://www.national.com/pf/LM/LM70.html
* Texas Instruments TMP121/TMP123
Information: http://focus.ti.com/docs/prod/folders/print/tmp121.html
Author:
Kaiwan N Billimoria <kaiwan@designergraphix.com>
@ -25,6 +27,14 @@ complement digital temperature (sent via the SIO line), is available in the
driver for interpretation. This driver makes use of the kernel's in-core
SPI support.
As a real (in-tree) example of this "SPI protocol driver" interfacing
with a "SPI master controller driver", see drivers/spi/spi_lm70llp.c
and its associated documentation.
The TMP121/TMP123 are very similar; main differences are 4 wire SPI inter-
face (read only) and 13-bit temperature data (0.0625 degrees celsius reso-
lution).
Thanks to
---------
Jean Delvare <khali@linux-fr.org> for mentoring the hwmon-side driver

2
Documentation/hwmon/lm85
View File

@ -164,7 +164,7 @@ configured individually according to the following options.
temperature. (PWM value from 0 to 255)
* pwm#_auto_pwm_minctl - this flags selects for temp#_auto_temp_off temperature
the bahaviour of fans. Write 1 to let fans spinning at
the behaviour of fans. Write 1 to let fans spinning at
pwm#_auto_pwm_min or write 0 to let them off.
NOTE: It has been reported that there is a bug in the LM85 that causes the flag

81
Documentation/hwmon/ltc4245 Normal file
View File

@ -0,0 +1,81 @@
Kernel driver ltc4245
=====================
Supported chips:
* Linear Technology LTC4245
Prefix: 'ltc4245'
Addresses scanned: 0x20-0x3f
Datasheet:
http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
Author: Ira W. Snyder <iws@ovro.caltech.edu>
Description
-----------
The LTC4245 controller allows a board to be safely inserted and removed
from a live backplane in multiple supply systems such as CompactPCI and
PCI Express.
Usage Notes
-----------
This driver does not probe for LTC4245 devices, due to the fact that some
of the possible addresses are unfriendly to probing. You will need to use
the "force" parameter to tell the driver where to find the device.
Example: the following will load the driver for an LTC4245 at address 0x23
on I2C bus #1:
$ modprobe ltc4245 force=1,0x23
Sysfs entries
-------------
The LTC4245 has built-in limits for over and under current warnings. This
makes it very likely that the reference circuit will be used.
This driver uses the values in the datasheet to change the register values
into the values specified in the sysfs-interface document. The current readings
rely on the sense resistors listed in Table 2: "Sense Resistor Values".
in1_input 12v input voltage (mV)
in2_input 5v input voltage (mV)
in3_input 3v input voltage (mV)
in4_input Vee (-12v) input voltage (mV)
in1_min_alarm 12v input undervoltage alarm
in2_min_alarm 5v input undervoltage alarm
in3_min_alarm 3v input undervoltage alarm
in4_min_alarm Vee (-12v) input undervoltage alarm
curr1_input 12v current (mA)
curr2_input 5v current (mA)
curr3_input 3v current (mA)
curr4_input Vee (-12v) current (mA)
curr1_max_alarm 12v overcurrent alarm
curr2_max_alarm 5v overcurrent alarm
curr3_max_alarm 3v overcurrent alarm
curr4_max_alarm Vee (-12v) overcurrent alarm
in5_input 12v output voltage (mV)
in6_input 5v output voltage (mV)
in7_input 3v output voltage (mV)
in8_input Vee (-12v) output voltage (mV)
in5_min_alarm 12v output undervoltage alarm
in6_min_alarm 5v output undervoltage alarm
in7_min_alarm 3v output undervoltage alarm
in8_min_alarm Vee (-12v) output undervoltage alarm
in9_input GPIO #1 voltage data
in10_input GPIO #2 voltage data
in11_input GPIO #3 voltage data
power1_input 12v power usage (mW)
power2_input 5v power usage (mW)
power3_input 3v power usage (mW)
power4_input Vee (-12v) power usage (mW)

5
Documentation/ide/warm-plug-howto.txt
View File

@ -11,3 +11,8 @@ unplug old device(s) and plug new device(s)
# echo -n "1" > /sys/class/ide_port/idex/scan
done
NOTE: please make sure that partitions are unmounted and that there are
no other active references to devices before doing "delete_devices" step,
also do not attempt "scan" step on devices currently in use -- otherwise
results may be unpredictable and lead to data loss if you're unlucky

109
Documentation/input/walkera0701.txt Normal file
View File

@ -0,0 +1,109 @@
Walkera WK-0701 transmitter is supplied with a ready to fly Walkera
helicopters such as HM36, HM37, HM60. The walkera0701 module enables to use
this transmitter as joystick
Devel homepage and download:
http://zub.fei.tuke.sk/walkera-wk0701/
or use cogito:
cg-clone http://zub.fei.tuke.sk/GIT/walkera0701-joystick
Connecting to PC:
At back side of transmitter S-video connector can be found. Modulation
pulses from processor to HF part can be found at pin 2 of this connector,
pin 3 is GND. Between pin 3 and CPU 5k6 resistor can be found. To get
modulation pulses to PC, signal pulses must be amplified.
Cable: (walkera TX to parport)
Walkera WK-0701 TX S-VIDEO connector:
(back side of TX)
__ __ S-video: canon25
/ |_| \ pin 2 (signal) NPN parport
/ O 4 3 O \ pin 3 (GND) LED ________________ 10 ACK
( O 2 1 O ) | C
\ ___ / 2 ________________________|\|_____|/
| [___] | |/| B |\
------- 3 __________________________________|________________ 25 GND
E
I use green LED and BC109 NPN transistor.
Software:
Build kernel with walkera0701 module. Module walkera0701 need exclusive
access to parport, modules like lp must be unloaded before loading
walkera0701 module, check dmesg for error messages. Connect TX to PC by
cable and run jstest /dev/input/js0 to see values from TX. If no value can
be changed by TX "joystick", check output from /proc/interrupts. Value for
(usually irq7) parport must increase if TX is on.
Technical details:
Driver use interrupt from parport ACK input bit to measure pulse length
using hrtimers.
Frame format:
Based on walkera WK-0701 PCM Format description by Shaul Eizikovich.
(downloaded from http://www.smartpropoplus.com/Docs/Walkera_Wk-0701_PCM.pdf)
Signal pulses:
(ANALOG)
SYNC BIN OCT
+---------+ +------+
| | | |
--+ +------+ +---
Frame:
SYNC , BIN1, OCT1, BIN2, OCT2 ... BIN24, OCT24, BIN25, next frame SYNC ..
pulse length:
Binary values: Analog octal values:
288 uS Binary 0 318 uS 000
438 uS Binary 1 398 uS 001
478 uS 010
558 uS 011
638 uS 100
1306 uS SYNC 718 uS 101
798 uS 110
878 uS 111
24 bin+oct values + 1 bin value = 24*4+1 bits = 97 bits
(Warning, pulses on ACK ar inverted by transistor, irq is rised up on sync
to bin change or octal value to bin change).
Binary data representations:
One binary and octal value can be grouped to nibble. 24 nibbles + one binary
values can be sampled between sync pulses.
Values for first four channels (analog joystick values) can be found in
first 10 nibbles. Analog value is represented by one sign bit and 9 bit
absolute binary value. (10 bits per channel). Next nibble is checksum for
first ten nibbles.
Next nibbles 12 .. 21 represents four channels (not all channels can be
directly controlled from TX). Binary representations ar the same as in first
four channels. In nibbles 22 and 23 is a special magic number. Nibble 24 is
checksum for nibbles 12..23.
After last octal value for nibble 24 and next sync pulse one additional
binary value can be sampled. This bit and magic number is not used in
software driver. Some details about this magic numbers can be found in
Walkera_Wk-0701_PCM.pdf.
Checksum calculation:
Summary of octal values in nibbles must be same as octal value in checksum
nibble (only first 3 bits are used). Binary value for checksum nibble is
calculated by sum of binary values in checked nibbles + sum of octal values
in checked nibbles divided by 8. Only bit 0 of this sum is used.

12
Documentation/ioctl/ioctl-number.txt
View File

@ -84,7 +84,7 @@ Code Seq# Include File Comments
'B' C0-FF advanced bbus
<mailto:maassen@uni-freiburg.de>
'C' all linux/soundcard.h
'D' all asm-s390/dasd.h
'D' all arch/s390/include/asm/dasd.h
'E' all linux/input.h
'F' all linux/fb.h
'H' all linux/hiddev.h
@ -97,6 +97,7 @@ Code Seq# Include File Comments
<http://linux01.gwdg.de/~alatham/ppdd.html>
'M' all linux/soundcard.h
'N' 00-1F drivers/usb/scanner.h
'O' 00-02 include/mtd/ubi-user.h UBI
'P' all linux/soundcard.h
'Q' all linux/soundcard.h
'R' 00-1F linux/random.h
@ -104,7 +105,7 @@ Code Seq# Include File Comments
'S' 80-81 scsi/scsi_ioctl.h conflict!
'S' 82-FF scsi/scsi.h conflict!
'T' all linux/soundcard.h conflict!
'T' all asm-i386/ioctls.h conflict!
'T' all arch/x86/include/asm/ioctls.h conflict!
'U' 00-EF linux/drivers/usb/usb.h
'V' all linux/vt.h
'W' 00-1F linux/watchdog.h conflict!
@ -119,7 +120,7 @@ Code Seq# Include File Comments
<mailto:natalia@nikhefk.nikhef.nl>
'c' 00-7F linux/comstats.h conflict!
'c' 00-7F linux/coda.h conflict!
'c' 80-9F asm-s390/chsc.h
'c' 80-9F arch/s390/include/asm/chsc.h
'd' 00-FF linux/char/drm/drm/h conflict!
'd' 00-DF linux/video_decoder.h conflict!
'd' F0-FF linux/digi1.h
@ -142,6 +143,9 @@ Code Seq# Include File Comments
'n' 00-7F linux/ncp_fs.h
'n' E0-FF video/matrox.h matroxfb
'o' 00-1F fs/ocfs2/ocfs2_fs.h OCFS2
'o' 00-03 include/mtd/ubi-user.h conflict! (OCFS2 and UBI overlaps)
'o' 40-41 include/mtd/ubi-user.h UBI
'o' 01-A1 include/linux/dvb/*.h DVB
'p' 00-0F linux/phantom.h conflict! (OpenHaptics needs this)
'p' 00-3F linux/mc146818rtc.h conflict!
'p' 40-7F linux/nvram.h
@ -166,7 +170,7 @@ Code Seq# Include File Comments
<mailto:oe@port.de>
0x80 00-1F linux/fb.h
0x81 00-1F linux/videotext.h
0x89 00-06 asm-i386/sockios.h
0x89 00-06 arch/x86/include/asm/sockios.h
0x89 0B-DF linux/sockios.h
0x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range
0x89 F0-FF linux/sockios.h SIOCDEVPRIVATE range

6
Documentation/kbuild/00-INDEX
View File

@ -1,5 +1,9 @@
00-INDEX
- this file: info on the kernel build process
- this file: info on the kernel build process
kbuild.txt
- developer information on kbuild
kconfig.txt
- usage help for make *config
kconfig-language.txt
- specification of Config Language, the language in Kconfig files
makefiles.txt

133
Documentation/kbuild/kbuild.txt Normal file
View File

@ -0,0 +1,133 @@
Environment variables
KCPPFLAGS
--------------------------------------------------
Additional options to pass when preprocessing. The preprocessing options
will be used in all cases where kbuild do preprocessing including
building C files and assembler files.
KAFLAGS
--------------------------------------------------
Additional options to the assembler.
KCFLAGS
--------------------------------------------------
Additional options to the C compiler.
KBUILD_VERBOSE
--------------------------------------------------
Set the kbuild verbosity. Can be assinged same values as "V=...".
See make help for the full list.
Setting "V=..." takes precedence over KBUILD_VERBOSE.
KBUILD_EXTMOD
--------------------------------------------------
Set the directory to look for the kernel source when building external
modules.
The directory can be specified in several ways:
1) Use "M=..." on the command line
2) Environmnet variable KBUILD_EXTMOD
3) Environmnet variable SUBDIRS
The possibilities are listed in the order they take precedence.
Using "M=..." will always override the others.
KBUILD_OUTPUT
--------------------------------------------------
Specify the output directory when building the kernel.
The output directory can also be specificed using "O=...".
Setting "O=..." takes precedence over KBUILD_OUTPUT
ARCH
--------------------------------------------------
Set ARCH to the architecture to be built.
In most cases the name of the architecture is the same as the
directory name found in the arch/ directory.
But some architectures suach as x86 and sparc has aliases.
x86: i386 for 32 bit, x86_64 for 64 bit
sparc: sparc for 32 bit, sparc64 for 64 bit
CROSS_COMPILE
--------------------------------------------------
Specify an optional fixed part of the binutils filename.
CROSS_COMPILE can be a part of the filename or the full path.
CROSS_COMPILE is also used for ccache is some setups.
CF
--------------------------------------------------
Additional options for sparse.
CF is often used on the command-line like this:
make CF=-Wbitwise C=2
INSTALL_PATH
--------------------------------------------------
INSTALL_PATH specifies where to place the updated kernel and system map
images. Default is /boot, but you can set it to other values
MODLIB
--------------------------------------------------
Specify where to install modules.
The default value is:
$(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
The value can be overridden in which case the default value is ignored.
INSTALL_MOD_PATH
--------------------------------------------------
INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
relocations required by build roots. This is not defined in the
makefile but the argument can be passed to make if needed.
INSTALL_MOD_STRIP
--------------------------------------------------
INSTALL_MOD_STRIP, if defined, will cause modules to be
stripped after they are installed. If INSTALL_MOD_STRIP is '1', then
the default option --strip-debug will be used. Otherwise,
INSTALL_MOD_STRIP will used as the options to the strip command.
INSTALL_FW_PATH
--------------------------------------------------
INSTALL_FW_PATH specify where to install the firmware blobs.
The default value is:
$(INSTALL_MOD_PATH)/lib/firmware
The value can be overridden in which case the default value is ignored.
INSTALL_HDR_PATH
--------------------------------------------------
INSTALL_HDR_PATH specify where to install user space headers when
executing "make headers_*".
The default value is:
$(objtree)/usr
$(objtree) is the directory where output files are saved.
The output directory is often set using "O=..." on the commandline.
The value can be overridden in which case the default value is ignored.
KBUILD_MODPOST_WARN
--------------------------------------------------
KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined
symbols in the final module linking stage.
KBUILD_MODPOST_FINAL
--------------------------------------------------
KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules.
This is solely usefull to speed up test compiles.
KBUILD_EXTRA_SYMBOLS
--------------------------------------------------
For modules use symbols from another modules.
See more details in modules.txt.
ALLSOURCE_ARCHS
--------------------------------------------------
For tags/TAGS/cscope targets, you can specify more than one archs
to be included in the databases, separated by blankspace. e.g.
$ make ALLSOURCE_ARCHS="x86 mips arm" tags

188
Documentation/kbuild/kconfig.txt Normal file
View File

@ -0,0 +1,188 @@
This file contains some assistance for using "make *config".
Use "make help" to list all of the possible configuration targets.
The xconfig ('qconf') and menuconfig ('mconf') programs also
have embedded help text. Be sure to check it for navigation,
search, and other general help text.
======================================================================
General
--------------------------------------------------
New kernel releases often introduce new config symbols. Often more
important, new kernel releases may rename config symbols. When
this happens, using a previously working .config file and running
"make oldconfig" won't necessarily produce a working new kernel
for you, so you may find that you need to see what NEW kernel
symbols have been introduced.
To see a list of new config symbols when using "make oldconfig", use
cp user/some/old.config .config
yes "" | make oldconfig >conf.new
and the config program will list as (NEW) any new symbols that have
unknown values. Of course, the .config file is also updated with
new (default) values, so you can use:
grep "(NEW)" conf.new
to see the new config symbols or you can 'diff' the previous and
new .config files to see the differences:
diff .config.old .config | less
(Yes, we need something better here.)
======================================================================
menuconfig
--------------------------------------------------
SEARCHING for CONFIG symbols
Searching in menuconfig:
The Search function searches for kernel configuration symbol
names, so you have to know something close to what you are
looking for.
Example:
/hotplug
This lists all config symbols that contain "hotplug",
e.g., HOTPLUG, HOTPLUG_CPU, MEMORY_HOTPLUG.
For search help, enter / followed TAB-TAB-TAB (to highlight
<Help>) and Enter. This will tell you that you can also use
regular expressions (regexes) in the search string, so if you
are not interested in MEMORY_HOTPLUG, you could try
/^hotplug
______________________________________________________________________
Color Themes for 'menuconfig'
It is possible to select different color themes using the variable
MENUCONFIG_COLOR. To select a theme use:
make MENUCONFIG_COLOR=<theme> menuconfig
Available themes are:
mono => selects colors suitable for monochrome displays
blackbg => selects a color scheme with black background
classic => theme with blue background. The classic look
bluetitle => a LCD friendly version of classic. (default)
______________________________________________________________________
Environment variables in 'menuconfig'
KCONFIG_ALLCONFIG
--------------------------------------------------
(partially based on lkml email from/by Rob Landley, re: miniconfig)
--------------------------------------------------
The allyesconfig/allmodconfig/allnoconfig/randconfig variants can
also use the environment variable KCONFIG_ALLCONFIG as a flag or a
filename that contains config symbols that the user requires to be
set to a specific value. If KCONFIG_ALLCONFIG is used without a
filename, "make *config" checks for a file named
"all{yes/mod/no/random}.config" (corresponding to the *config command
that was used) for symbol values that are to be forced. If this file
is not found, it checks for a file named "all.config" to contain forced
values.
This enables you to create "miniature" config (miniconfig) or custom
config files containing just the config symbols that you are interested
in. Then the kernel config system generates the full .config file,
including dependencies of your miniconfig file, based on the miniconfig
file.
This 'KCONFIG_ALLCONFIG' file is a config file which contains
(usually a subset of all) preset config symbols. These variable
settings are still subject to normal dependency checks.
Examples:
KCONFIG_ALLCONFIG=custom-notebook.config make allnoconfig
or
KCONFIG_ALLCONFIG=mini.config make allnoconfig
or
make KCONFIG_ALLCONFIG=mini.config allnoconfig
These examples will disable most options (allnoconfig) but enable or
disable the options that are explicitly listed in the specified
mini-config files.
KCONFIG_NOSILENTUPDATE
--------------------------------------------------
If this variable has a non-blank value, it prevents silent kernel
config udpates (requires explicit updates).
KCONFIG_CONFIG
--------------------------------------------------
This environment variable can be used to specify a default kernel config
file name to override the default name of ".config".
KCONFIG_OVERWRITECONFIG
--------------------------------------------------
If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not
break symlinks when .config is a symlink to somewhere else.
KCONFIG_NOTIMESTAMP
--------------------------------------------------
If this environment variable exists and is non-null, the timestamp line
in generated .config files is omitted.
KCONFIG_AUTOCONFIG
--------------------------------------------------
This environment variable can be set to specify the path & name of the
"auto.conf" file. Its default value is "include/config/auto.conf".
KCONFIG_AUTOHEADER
--------------------------------------------------
This environment variable can be set to specify the path & name of the
"autoconf.h" (header) file. Its default value is "include/linux/autoconf.h".
______________________________________________________________________
menuconfig User Interface Options
----------------------------------------------------------------------
MENUCONFIG_MODE
--------------------------------------------------
This mode shows all sub-menus in one large tree.
Example:
MENUCONFIG_MODE=single_menu make menuconfig
======================================================================
xconfig
--------------------------------------------------
Searching in xconfig:
The Search function searches for kernel configuration symbol
names, so you have to know something close to what you are
looking for.
Example:
Ctrl-F hotplug
or
Menu: File, Search, hotplug
lists all config symbol entries that contain "hotplug" in
the symbol name. In this Search dialog, you may change the
config setting for any of the entries that are not grayed out.
You can also enter a different search string without having
to return to the main menu.
======================================================================
gconfig
--------------------------------------------------
Searching in gconfig:
None (gconfig isn't maintained as well as xconfig or menuconfig);
however, gconfig does have a few more viewing choices than
xconfig does.
###

4
Documentation/kbuild/modules.txt
View File

@ -253,7 +253,7 @@ following files:
# Module specific targets
genbin:
echo "X" > 8123_bin_shipped
echo "X" > 8123_bin.o_shipped
In example 2, we are down to two fairly simple files and for simple
@ -279,7 +279,7 @@ following files:
# Module specific targets
genbin:
echo "X" > 8123_bin_shipped
echo "X" > 8123_bin.o_shipped
endif

34
Documentation/kernel-doc-nano-HOWTO.txt
View File

@ -71,6 +71,11 @@ The @argument descriptions must begin on the very next line following
this opening short function description line, with no intervening
empty comment lines.
If a function parameter is "..." (varargs), it should be listed in
kernel-doc notation as:
* @...: description
Example kernel-doc data structure comment.
/**
@ -282,6 +287,32 @@ struct my_struct {
};
Including documentation blocks in source files
----------------------------------------------
To facilitate having source code and comments close together, you can
include kernel-doc documentation blocks that are free-form comments
instead of being kernel-doc for functions, structures, unions,
enums, or typedefs. This could be used for something like a
theory of operation for a driver or library code, for example.
This is done by using a DOC: section keyword with a section title. E.g.:
/**
* DOC: Theory of Operation
*
* The whizbang foobar is a dilly of a gizmo. It can do whatever you
* want it to do, at any time. It reads your mind. Here's how it works.
*
* foo bar splat
*
* The only drawback to this gizmo is that is can sometimes damage
* hardware, software, or its subject(s).
*/
DOC: sections are used in SGML templates files as indicated below.
How to make new SGML template files
-----------------------------------
@ -302,6 +333,9 @@ exported using EXPORT_SYMBOL.
!F<filename> <function [functions...]> is replaced by the
documentation, in <filename>, for the functions listed.
!P<filename> <section title> is replaced by the contents of the DOC:
section titled <section title> from <filename>.
Spaces are allowed in <section title>; do not quote the <section title>.
Tim.
*/ <twaugh@redhat.com>

122
Documentation/kernel-parameters.txt
View File

@ -91,6 +91,7 @@ parameter is applicable:
SUSPEND System suspend states are enabled.
FTRACE Function tracing enabled.
TS Appropriate touchscreen support is enabled.
UMS USB Mass Storage support is enabled.
USB USB support is enabled.
USBHID USB Human Interface Device support is enabled.
V4L Video For Linux support is enabled.
@ -140,6 +141,7 @@ and is between 256 and 4096 characters. It is defined in the file
ht -- run only enough ACPI to enable Hyper Threading
strict -- Be less tolerant of platforms that are not
strictly ACPI specification compliant.
rsdt -- prefer RSDT over (default) XSDT
See also Documentation/power/pm.txt, pci=noacpi
@ -150,16 +152,20 @@ and is between 256 and 4096 characters. It is defined in the file
default: 0
acpi_sleep= [HW,ACPI] Sleep options
Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig, old_ordering }
See Documentation/power/video.txt for s3_bios and s3_mode.
Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
old_ordering, s4_nonvs }
See Documentation/power/video.txt for information on
s3_bios and s3_mode.
s3_beep is for debugging; it makes the PC's speaker beep
as soon as the kernel's real-mode entry point is called.
s4_nohwsig prevents ACPI hardware signature from being
used during resume from hibernation.
old_ordering causes the ACPI 1.0 ordering of the _PTS
control method, wrt putting devices into low power
states, to be enforced (the ACPI 2.0 ordering of _PTS is
used by default).
control method, with respect to putting devices into
low power states, to be enforced (the ACPI 2.0 ordering
of _PTS is used by default).
s4_nonvs prevents the kernel from saving/restoring the
ACPI NVS memory during hibernation.
acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
Format: { level | edge | high | low }
@ -194,7 +200,7 @@ and is between 256 and 4096 characters. It is defined in the file
acpi_skip_timer_override [HW,ACPI]
Recognize and ignore IRQ0/pin2 Interrupt Override.
For broken nForce2 BIOS resulting in XT-PIC timer.
acpi_use_timer_override [HW,ACPI}
acpi_use_timer_override [HW,ACPI]
Use timer override. For some broken Nvidia NF5 boards
that require a timer override, but don't have
HPET
@ -469,8 +475,8 @@ and is between 256 and 4096 characters. It is defined in the file
clearcpuid=BITNUM [X86]
Disable CPUID feature X for the kernel. See
include/asm-x86/cpufeature.h for the valid bit numbers.
Note the Linux specific bits are not necessarily
arch/x86/include/asm/cpufeature.h for the valid bit
numbers. Note the Linux specific bits are not necessarily
stable over kernel options, but the vendor specific
ones should be.
Also note that user programs calling CPUID directly
@ -551,6 +557,11 @@ and is between 256 and 4096 characters. It is defined in the file
not work reliably with all consoles, but is known
to work with serial and VGA consoles.
coredump_filter=
[KNL] Change the default value for
/proc/<pid>/coredump_filter.
See also Documentation/filesystems/proc.txt.
cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
Format:
<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
@ -823,8 +834,8 @@ and is between 256 and 4096 characters. It is defined in the file
hlt [BUGS=ARM,SH]
hvc_iucv= [S390] Number of z/VM IUCV Hypervisor console (HVC)
back-ends. Valid parameters: 0..8
hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC)
terminal devices. Valid values: 0..8
i8042.debug [HW] Toggle i8042 debug mode
i8042.direct [HW] Put keyboard port into non-translated mode
@ -872,17 +883,19 @@ and is between 256 and 4096 characters. It is defined in the file
See Documentation/ide/ide.txt.
idle= [X86]
Format: idle=poll or idle=mwait, idle=halt, idle=nomwait
Poll forces a polling idle loop that can slightly improves the performance
of waking up a idle CPU, but will use a lot of power and make the system
run hot. Not recommended.
idle=mwait. On systems which support MONITOR/MWAIT but the kernel chose
to not use it because it doesn't save as much power as a normal idle
loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same
as idle=poll.
idle=halt. Halt is forced to be used for CPU idle.
Format: idle=poll, idle=mwait, idle=halt, idle=nomwait
Poll forces a polling idle loop that can slightly
improve the performance of waking up a idle CPU, but
will use a lot of power and make the system run hot.
Not recommended.
idle=mwait: On systems which support MONITOR/MWAIT but
the kernel chose to not use it because it doesn't save
as much power as a normal idle loop, use the
MONITOR/MWAIT idle loop anyways. Performance should be
the same as idle=poll.
idle=halt: Halt is forced to be used for CPU idle.
In such case C2/C3 won't be used again.
idle=nomwait. Disable mwait for CPU C-states
idle=nomwait: Disable mwait for CPU C-states
ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
Claim all unknown PCI IDE storage controllers.
@ -913,6 +926,10 @@ and is between 256 and 4096 characters. It is defined in the file
inttest= [IA64]
iomem= Disable strict checking of access to MMIO memory
strict regions from userspace.
relaxed
iommu= [x86]
off
force
@ -1064,8 +1081,8 @@ and is between 256 and 4096 characters. It is defined in the file
lapic [X86-32,APIC] Enable the local APIC even if BIOS
disabled it.
lapic_timer_c2_ok [X86-32,x86-64,APIC] trust the local apic timer in
C2 power state.
lapic_timer_c2_ok [X86-32,x86-64,APIC] trust the local apic timer
in C2 power state.
libata.dma= [LIBATA] DMA control
libata.dma=0 Disable all PATA and SATA DMA
@ -1117,6 +1134,8 @@ and is between 256 and 4096 characters. It is defined in the file
If there are multiple matching configurations changing
the same attribute, the last one is used.
lmb=debug [KNL] Enable lmb debug messages.
load_ramdisk= [RAM] List of ramdisks to load from floppy
See Documentation/blockdev/ramdisk.txt.
@ -1550,6 +1569,9 @@ and is between 256 and 4096 characters. It is defined in the file
nosoftlockup [KNL] Disable the soft-lockup detector.
noswapaccount [KNL] Disable accounting of swap in memory resource
controller. (See Documentation/controllers/memory.txt)
nosync [HW,M68K] Disables sync negotiation for all devices.
notsc [BUGS=X86-32] Disable Time Stamp Counter
@ -1569,6 +1591,10 @@ and is between 256 and 4096 characters. It is defined in the file
nr_uarts= [SERIAL] maximum number of UARTs to be registered.
ohci1394_dma=early [HW] enable debugging via the ohci1394 driver.
See Documentation/debugging-via-ohci1394.txt for more
info.
olpc_ec_timeout= [OLPC] ms delay when issuing EC commands
Rather than timing out after 20 ms if an EC
command is not properly ACKed, override the length
@ -1793,10 +1819,10 @@ and is between 256 and 4096 characters. It is defined in the file
autoconfiguration.
Ranges are in pairs (memory base and size).
dynamic_printk
Enables pr_debug()/dev_dbg() calls if
CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled. These can also
be switched on/off via <debugfs>/dynamic_printk/modules
dynamic_printk Enables pr_debug()/dev_dbg() calls if
CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled.
These can also be switched on/off via
<debugfs>/dynamic_printk/modules
print-fatal-signals=
[KNL] debug: print fatal signals
@ -1884,7 +1910,7 @@ and is between 256 and 4096 characters. It is defined in the file
reboot= [BUGS=X86-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
Format: <reboot_mode>[,<reboot_mode2>[,...]]
See arch/*/kernel/reboot.c or arch/*/kernel/process.c
See arch/*/kernel/reboot.c or arch/*/kernel/process.c
relax_domain_level=
[KNL, SMP] Set scheduler's default relax_domain_level.
@ -2284,7 +2310,8 @@ and is between 256 and 4096 characters. It is defined in the file
thermal.psv= [HW,ACPI]
-1: disable all passive trip points
<degrees C>: override all passive trip points to this value
<degrees C>: override all passive trip points to this
value
thermal.tzp= [HW,ACPI]
Specify global default ACPI thermal zone polling rate
@ -2372,6 +2399,41 @@ and is between 256 and 4096 characters. It is defined in the file
usbhid.mousepoll=
[USBHID] The interval which mice are to be polled at.
usb-storage.delay_use=
[UMS] The delay in seconds before a new device is
scanned for Logical Units (default 5).
usb-storage.quirks=
[UMS] A list of quirks entries to supplement or
override the built-in unusual_devs list. List
entries are separated by commas. Each entry has
the form VID:PID:Flags where VID and PID are Vendor
and Product ID values (4-digit hex numbers) and
Flags is a set of characters, each corresponding
to a common usb-storage quirk flag as follows:
a = SANE_SENSE (collect more than 18 bytes
of sense data);
c = FIX_CAPACITY (decrease the reported
device capacity by one sector);
h = CAPACITY_HEURISTICS (decrease the
reported device capacity by one
sector if the number is odd);
i = IGNORE_DEVICE (don't bind to this
device);
l = NOT_LOCKABLE (don't try to lock and
unlock ejectable media);
m = MAX_SECTORS_64 (don't transfer more
than 64 sectors = 32 KB at a time);
o = CAPACITY_OK (accept the capacity
reported by the device);
r = IGNORE_RESIDUE (the device reports
bogus residue values);
s = SINGLE_LUN (the device has only one
Logical Unit);
w = NO_WP_DETECT (don't test whether the
medium is write-protected).
Example: quirks=0419:aaf5:rl,0421:0433:rc
add_efi_memmap [EFI; x86-32,X86-64] Include EFI memory map in
kernel's map of available physical RAM.
@ -2432,8 +2494,8 @@ and is between 256 and 4096 characters. It is defined in the file
Format:
<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
norandmaps Don't use address space randomization
Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space
norandmaps Don't use address space randomization. Equivalent to
echo 0 > /proc/sys/kernel/randomize_va_space
______________________________________________________________________

4
Documentation/kobject.txt
View File

@ -118,8 +118,8 @@ the name of the kobject, call kobject_rename():
int kobject_rename(struct kobject *kobj, const char *new_name);
Note kobject_rename does perform any locking or have a solid notion of
what names are valid so the provide must provide their own sanity checking
kobject_rename does not perform any locking or have a solid notion of
what names are valid so the caller must provide their own sanity checking
and serialization.
There is a function called kobject_set_name() but that is legacy cruft and

5
Documentation/kprobes.txt
View File

@ -497,7 +497,10 @@ The first column provides the kernel address where the probe is inserted.
The second column identifies the type of probe (k - kprobe, r - kretprobe
and j - jprobe), while the third column specifies the symbol+offset of
the probe. If the probed function belongs to a module, the module name
is also specified.
is also specified. Following columns show probe status. If the probe is on
a virtual address that is no longer valid (module init sections, module
virtual addresses that correspond to modules that've been unloaded),
such probes are marked with [GONE].
/debug/kprobes/enabled: Turn kprobes ON/OFF

2
Documentation/laptops/thinkpad-acpi.txt
View File

@ -1475,7 +1475,7 @@ Sysfs interface changelog:
0x020100: Marker for thinkpad-acpi with hot key NVRAM polling
support. If you must, use it to know you should not
start an userspace NVRAM poller (allows to detect when
start a userspace NVRAM poller (allows to detect when
NVRAM is compiled out by the user because it is
unneeded/undesired in the first place).
0x020101: Marker for thinkpad-acpi with hot key NVRAM polling

66
Documentation/lguest/lguest.c
View File

@ -481,51 +481,6 @@ static unsigned long load_initrd(const char *name, unsigned long mem)
/* We return the initrd size. */
return len;
}
/* Once we know how much memory we have we can construct simple linear page
* tables which set virtual == physical which will get the Guest far enough
* into the boot to create its own.
*
* We lay them out of the way, just below the initrd (which is why we need to
* know its size here). */
static unsigned long setup_pagetables(unsigned long mem,
unsigned long initrd_size)
{
unsigned long *pgdir, *linear;
unsigned int mapped_pages, i, linear_pages;
unsigned int ptes_per_page = getpagesize()/sizeof(void *);
mapped_pages = mem/getpagesize();
/* Each PTE page can map ptes_per_page pages: how many do we need? */
linear_pages = (mapped_pages + ptes_per_page-1)/ptes_per_page;
/* We put the toplevel page directory page at the top of memory. */
pgdir = from_guest_phys(mem) - initrd_size - getpagesize();
/* Now we use the next linear_pages pages as pte pages */
linear = (void *)pgdir - linear_pages*getpagesize();
/* Linear mapping is easy: put every page's address into the mapping in
* order. PAGE_PRESENT contains the flags Present, Writable and
* Executable. */
for (i = 0; i < mapped_pages; i++)
linear[i] = ((i * getpagesize()) | PAGE_PRESENT);
/* The top level points to the linear page table pages above. */
for (i = 0; i < mapped_pages; i += ptes_per_page) {
pgdir[i/ptes_per_page]
= ((to_guest_phys(linear) + i*sizeof(void *))
| PAGE_PRESENT);
}
verbose("Linear mapping of %u pages in %u pte pages at %#lx\n",
mapped_pages, linear_pages, to_guest_phys(linear));
/* We return the top level (guest-physical) address: the kernel needs
* to know where it is. */
return to_guest_phys(pgdir);
}
/*:*/
/* Simple routine to roll all the commandline arguments together with spaces
@ -548,13 +503,13 @@ static void concat(char *dst, char *args[])
/*L:185 This is where we actually tell the kernel to initialize the Guest. We
* saw the arguments it expects when we looked at initialize() in lguest_user.c:
* the base of Guest "physical" memory, the top physical page to allow, the
* top level pagetable and the entry point for the Guest. */
static int tell_kernel(unsigned long pgdir, unsigned long start)
* the base of Guest "physical" memory, the top physical page to allow and the
* entry point for the Guest. */
static int tell_kernel(unsigned long start)
{
unsigned long args[] = { LHREQ_INITIALIZE,
(unsigned long)guest_base,
guest_limit / getpagesize(), pgdir, start };
guest_limit / getpagesize(), start };
int fd;
verbose("Guest: %p - %p (%#lx)\n",
@ -1030,7 +985,7 @@ static void update_device_status(struct device *dev)
/* Zero out the virtqueues. */
for (vq = dev->vq; vq; vq = vq->next) {
memset(vq->vring.desc, 0,
vring_size(vq->config.num, getpagesize()));
vring_size(vq->config.num, LGUEST_VRING_ALIGN));
lg_last_avail(vq) = 0;
}
} else if (dev->desc->status & VIRTIO_CONFIG_S_FAILED) {
@ -1211,7 +1166,7 @@ static void add_virtqueue(struct device *dev, unsigned int num_descs,
void *p;
/* First we need some memory for this virtqueue. */
pages = (vring_size(num_descs, getpagesize()) + getpagesize() - 1)
pages = (vring_size(num_descs, LGUEST_VRING_ALIGN) + getpagesize() - 1)
/ getpagesize();
p = get_pages(pages);
@ -1228,7 +1183,7 @@ static void add_virtqueue(struct device *dev, unsigned int num_descs,
vq->config.pfn = to_guest_phys(p) / getpagesize();
/* Initialize the vring. */
vring_init(&vq->vring, num_descs, p, getpagesize());
vring_init(&vq->vring, num_descs, p, LGUEST_VRING_ALIGN);
/* Append virtqueue to this device's descriptor. We use
* device_config() to get the end of the device's current virtqueues;
@ -1941,7 +1896,7 @@ int main(int argc, char *argv[])
{
/* Memory, top-level pagetable, code startpoint and size of the
* (optional) initrd. */
unsigned long mem = 0, pgdir, start, initrd_size = 0;
unsigned long mem = 0, start, initrd_size = 0;
/* Two temporaries and the /dev/lguest file descriptor. */
int i, c, lguest_fd;
/* The boot information for the Guest. */
@ -2040,9 +1995,6 @@ int main(int argc, char *argv[])
boot->hdr.type_of_loader = 0xFF;
}
/* Set up the initial linear pagetables, starting below the initrd. */
pgdir = setup_pagetables(mem, initrd_size);
/* The Linux boot header contains an "E820" memory map: ours is a
* simple, single region. */
boot->e820_entries = 1;
@ -2064,7 +2016,7 @@ int main(int argc, char *argv[])
/* We tell the kernel to initialize the Guest: this returns the open
* /dev/lguest file descriptor. */
lguest_fd = tell_kernel(pgdir, start);
lguest_fd = tell_kernel(start);
/* We clone off a thread, which wakes the Launcher whenever one of the
* input file descriptors needs attention. We call this the Waker, and

51
Documentation/lockstat.txt
View File

@ -71,35 +71,50 @@ Look at the current lock statistics:
# less /proc/lock_stat
01 lock_stat version 0.2
01 lock_stat version 0.3
02 -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
03 class name con-bounces contentions waittime-min waittime-max waittime-total acq-bounces acquisitions holdtime-min holdtime-max holdtime-total
04 -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
05
06 &inode->i_data.tree_lock-W: 15 21657 0.18 1093295.30 11547131054.85 58 10415 0.16 87.51 6387.60
07 &inode->i_data.tree_lock-R: 0 0 0.00 0.00 0.00 23302 231198 0.25 8.45 98023.38
08 --------------------------
09 &inode->i_data.tree_lock 0 [<ffffffff8027c08f>] add_to_page_cache+0x5f/0x190
10
11 ...............................................................................................................................................................................................
12
13 dcache_lock: 1037 1161 0.38 45.32 774.51 6611 243371 0.15 306.48 77387.24
14 -----------
15 dcache_lock 180 [<ffffffff802c0d7e>] sys_getcwd+0x11e/0x230
16 dcache_lock 165 [<ffffffff802c002a>] d_alloc+0x15a/0x210
17 dcache_lock 33 [<ffffffff8035818d>] _atomic_dec_and_lock+0x4d/0x70
18 dcache_lock 1 [<ffffffff802beef8>] shrink_dcache_parent+0x18/0x130
06 &mm->mmap_sem-W: 233 538 18446744073708 22924.27 607243.51 1342 45806 1.71 8595.89 1180582.34
07 &mm->mmap_sem-R: 205 587 18446744073708 28403.36 731975.00 1940 412426 0.58 187825.45 6307502.88
08 ---------------
09 &mm->mmap_sem 487 [<ffffffff8053491f>] do_page_fault+0x466/0x928
10 &mm->mmap_sem 179 [<ffffffff802a6200>] sys_mprotect+0xcd/0x21d
11 &mm->mmap_sem 279 [<ffffffff80210a57>] sys_mmap+0x75/0xce
12 &mm->mmap_sem 76 [<ffffffff802a490b>] sys_munmap+0x32/0x59
13 ---------------
14 &mm->mmap_sem 270 [<ffffffff80210a57>] sys_mmap+0x75/0xce
15 &mm->mmap_sem 431 [<ffffffff8053491f>] do_page_fault+0x466/0x928
16 &mm->mmap_sem 138 [<ffffffff802a490b>] sys_munmap+0x32/0x59
17 &mm->mmap_sem 145 [<ffffffff802a6200>] sys_mprotect+0xcd/0x21d
18
19 ...............................................................................................................................................................................................
20
21 dcache_lock: 621 623 0.52 118.26 1053.02 6745 91930 0.29 316.29 118423.41
22 -----------
23 dcache_lock 179 [<ffffffff80378274>] _atomic_dec_and_lock+0x34/0x54
24 dcache_lock 113 [<ffffffff802cc17b>] d_alloc+0x19a/0x1eb
25 dcache_lock 99 [<ffffffff802ca0dc>] d_rehash+0x1b/0x44
26 dcache_lock 104 [<ffffffff802cbca0>] d_instantiate+0x36/0x8a
27 -----------
28 dcache_lock 192 [<ffffffff80378274>] _atomic_dec_and_lock+0x34/0x54
29 dcache_lock 98 [<ffffffff802ca0dc>] d_rehash+0x1b/0x44
30 dcache_lock 72 [<ffffffff802cc17b>] d_alloc+0x19a/0x1eb
31 dcache_lock 112 [<ffffffff802cbca0>] d_instantiate+0x36/0x8a
This excerpt shows the first two lock class statistics. Line 01 shows the
output version - each time the format changes this will be updated. Line 02-04
show the header with column descriptions. Lines 05-10 and 13-18 show the actual
show the header with column descriptions. Lines 05-18 and 20-31 show the actual
statistics. These statistics come in two parts; the actual stats separated by a
short separator (line 08, 14) from the contention points.
short separator (line 08, 13) from the contention points.
The first lock (05-10) is a read/write lock, and shows two lines above the
The first lock (05-18) is a read/write lock, and shows two lines above the
short separator. The contention points don't match the column descriptors,
they have two: contentions and [<IP>] symbol.
they have two: contentions and [<IP>] symbol. The second set of contention
points are the points we're contending with.
The integer part of the time values is in us.
View the top contending locks:

6
Documentation/magic-number.txt
View File

@ -125,14 +125,14 @@ TRIDENT_CARD_MAGIC 0x5072696E trident_card sound/oss/trident.c
ROUTER_MAGIC 0x524d4157 wan_device include/linux/wanrouter.h
SCC_MAGIC 0x52696368 gs_port drivers/char/scc.h
SAVEKMSG_MAGIC1 0x53415645 savekmsg arch/*/amiga/config.c
GDA_MAGIC 0x58464552 gda include/asm-mips64/sn/gda.h
GDA_MAGIC 0x58464552 gda arch/mips/include/asm/sn/gda.h
RED_MAGIC1 0x5a2cf071 (any) mm/slab.c
STL_PORTMAGIC 0x5a7182c9 stlport include/linux/stallion.h
EEPROM_MAGIC_VALUE 0x5ab478d2 lanai_dev drivers/atm/lanai.c
HDLCDRV_MAGIC 0x5ac6e778 hdlcdrv_state include/linux/hdlcdrv.h
EPCA_MAGIC 0x5c6df104 channel include/linux/epca.h
PCXX_MAGIC 0x5c6df104 channel drivers/char/pcxx.h
KV_MAGIC 0x5f4b565f kernel_vars_s include/asm-mips64/sn/klkernvars.h
KV_MAGIC 0x5f4b565f kernel_vars_s arch/mips/include/asm/sn/klkernvars.h
I810_STATE_MAGIC 0x63657373 i810_state sound/oss/i810_audio.c
TRIDENT_STATE_MAGIC 0x63657373 trient_state sound/oss/trident.c
M3_CARD_MAGIC 0x646e6f50 m3_card sound/oss/maestro3.c
@ -158,7 +158,7 @@ CCB_MAGIC 0xf2691ad2 ccb drivers/scsi/ncr53c8xx.c
QUEUE_MAGIC_FREE 0xf7e1c9a3 queue_entry drivers/scsi/arm/queue.c
QUEUE_MAGIC_USED 0xf7e1cc33 queue_entry drivers/scsi/arm/queue.c
HTB_CMAGIC 0xFEFAFEF1 htb_class net/sched/sch_htb.c
NMI_MAGIC 0x48414d4d455201 nmi_s include/asm-mips64/sn/nmi.h
NMI_MAGIC 0x48414d4d455201 nmi_s arch/mips/include/asm/sn/nmi.h
Note that there are also defined special per-driver magic numbers in sound
memory management. See include/sound/sndmagic.h for complete list of them. Many

16
Documentation/memory-hotplug.txt
View File

@ -124,7 +124,7 @@ config options.
This option can be kernel module too.
--------------------------------
3 sysfs files for memory hotplug
4 sysfs files for memory hotplug
--------------------------------
All sections have their device information under /sys/devices/system/memory as
@ -138,11 +138,12 @@ For example, assume 1GiB section size. A device for a memory starting at
(0x100000000 / 1Gib = 4)
This device covers address range [0x100000000 ... 0x140000000)
Under each section, you can see 3 files.
Under each section, you can see 4 files.
/sys/devices/system/memory/memoryXXX/phys_index
/sys/devices/system/memory/memoryXXX/phys_device
/sys/devices/system/memory/memoryXXX/state
/sys/devices/system/memory/memoryXXX/removable
'phys_index' : read-only and contains section id, same as XXX.
'state' : read-write
@ -150,10 +151,20 @@ Under each section, you can see 3 files.
at write: user can specify "online", "offline" command
'phys_device': read-only: designed to show the name of physical memory device.
This is not well implemented now.
'removable' : read-only: contains an integer value indicating
whether the memory section is removable or not
removable. A value of 1 indicates that the memory
section is removable and a value of 0 indicates that
it is not removable.
NOTE:
These directories/files appear after physical memory hotplug phase.
If CONFIG_NUMA is enabled the
/sys/devices/system/memory/memoryXXX memory section
directories can also be accessed via symbolic links located in
the /sys/devices/system/node/node* directories. For example:
/sys/devices/system/node/node0/memory9 -> ../../memory/memory9
--------------------------------
4. Physical memory hot-add phase
@ -365,7 +376,6 @@ node if necessary.
- allowing memory hot-add to ZONE_MOVABLE. maybe we need some switch like
sysctl or new control file.
- showing memory section and physical device relationship.
- showing memory section and node relationship (maybe good for NUMA)
- showing memory section is under ZONE_MOVABLE or not
- test and make it better memory offlining.
- support HugeTLB page migration and offlining.

2
Documentation/mips/AU1xxx_IDE.README
View File

@ -44,7 +44,7 @@ FILES, CONFIGS AND COMPATABILITY
Two files are introduced:
a) 'include/asm-mips/mach-au1x00/au1xxx_ide.h'
a) 'arch/mips/include/asm/mach-au1x00/au1xxx_ide.h'
containes : struct _auide_hwif
timing parameters for PIO mode 0/1/2/3/4
timing parameters for MWDMA 0/1/2

2
Documentation/networking/rxrpc.txt
View File

@ -540,7 +540,7 @@ A client would issue an operation by:
MSG_MORE should be set in msghdr::msg_flags on all but the last part of
the request. Multiple requests may be made simultaneously.
If a call is intended to go to a destination other then the default
If a call is intended to go to a destination other than the default
specified through connect(), then msghdr::msg_name should be set on the
first request message of that call.

2
Documentation/networking/tuntap.txt
View File

@ -118,7 +118,7 @@ As mentioned above, main purpose of TUN/TAP driver is tunneling.
It is used by VTun (http://vtun.sourceforge.net).
Another interesting application using TUN/TAP is pipsecd
(http://perso.enst.fr/~beyssac/pipsec/), an userspace IPSec
(http://perso.enst.fr/~beyssac/pipsec/), a userspace IPSec
implementation that can use complete kernel routing (unlike FreeS/WAN).
3. How does Virtual network device actually work ?

31
Documentation/nommu-mmap.txt
View File

@ -109,12 +109,18 @@ and it's also much more restricted in the latter case:
FURTHER NOTES ON NO-MMU MMAP
============================
(*) A request for a private mapping of less than a page in size may not return
a page-aligned buffer. This is because the kernel calls kmalloc() to
allocate the buffer, not get_free_page().
(*) A request for a private mapping of a file may return a buffer that is not
page-aligned. This is because XIP may take place, and the data may not be
paged aligned in the backing store.
(*) A list of all the mappings on the system is visible through /proc/maps in
no-MMU mode.
(*) A request for an anonymous mapping will always be page aligned. If
possible the size of the request should be a power of two otherwise some
of the space may be wasted as the kernel must allocate a power-of-2
granule but will only discard the excess if appropriately configured as
this has an effect on fragmentation.
(*) A list of all the private copy and anonymous mappings on the system is
visible through /proc/maps in no-MMU mode.
(*) A list of all the mappings in use by a process is visible through
/proc/<pid>/maps in no-MMU mode.
@ -242,3 +248,18 @@ PROVIDING SHAREABLE BLOCK DEVICE SUPPORT
Provision of shared mappings on block device files is exactly the same as for
character devices. If there isn't a real device underneath, then the driver
should allocate sufficient contiguous memory to honour any supported mapping.
=================================
ADJUSTING PAGE TRIMMING BEHAVIOUR
=================================
NOMMU mmap automatically rounds up to the nearest power-of-2 number of pages
when performing an allocation. This can have adverse effects on memory
fragmentation, and as such, is left configurable. The default behaviour is to
aggressively trim allocations and discard any excess pages back in to the page
allocator. In order to retain finer-grained control over fragmentation, this
behaviour can either be disabled completely, or bumped up to a higher page
watermark where trimming begins.
Page trimming behaviour is configurable via the sysctl `vm.nr_trim_pages'.

2
Documentation/powerpc/cpu_features.txt
View File

@ -31,7 +31,7 @@ anyways).
After detecting the processor type, the kernel patches out sections of code
that shouldn't be used by writing nop's over it. Using cpufeatures requires
just 2 macros (found in include/asm-ppc/cputable.h), as seen in head.S
just 2 macros (found in arch/powerpc/include/asm/cputable.h), as seen in head.S
transfer_to_handler:
#ifdef CONFIG_ALTIVEC

39
Documentation/powerpc/dts-bindings/4xx/ndfc.txt Normal file
View File

@ -0,0 +1,39 @@
AMCC NDFC (NanD Flash Controller)
Required properties:
- compatible : "ibm,ndfc".
- reg : should specify chip select and size used for the chip (0x2000).
Optional properties:
- ccr : NDFC config and control register value (default 0).
- bank-settings : NDFC bank configuration register value (default 0).
Notes:
- partition(s) - follows the OF MTD standard for partitions
Example:
ndfc@1,0 {
compatible = "ibm,ndfc";
reg = <0x00000001 0x00000000 0x00002000>;
ccr = <0x00001000>;
bank-settings = <0x80002222>;
#address-cells = <1>;
#size-cells = <1>;
nand {
#address-cells = <1>;
#size-cells = <1>;
partition@0 {
label = "kernel";
reg = <0x00000000 0x00200000>;
};
partition@200000 {
label = "root";
reg = <0x00200000 0x03E00000>;
};
};
};

32
Documentation/powerpc/dts-bindings/fsl/board.txt
View File

@ -18,7 +18,7 @@ This is the memory-mapped registers for on board FPGA.
Required properities:
- compatible : should be "fsl,fpga-pixis".
- reg : should contain the address and the lenght of the FPPGA register
- reg : should contain the address and the length of the FPPGA register
set.
Example (MPC8610HPCD):
@ -27,3 +27,33 @@ Example (MPC8610HPCD):
compatible = "fsl,fpga-pixis";
reg = <0xe8000000 32>;
};
* Freescale BCSR GPIO banks
Some BCSR registers act as simple GPIO controllers, each such
register can be represented by the gpio-controller node.
Required properities:
- compatible : Should be "fsl,<board>-bcsr-gpio".
- reg : Should contain the address and the length of the GPIO bank
register.
- #gpio-cells : Should be two. The first cell is the pin number and the
second cell is used to specify optional paramters (currently unused).
- gpio-controller : Marks the port as GPIO controller.
Example:
bcsr@1,0 {
#address-cells = <1>;
#size-cells = <1>;
compatible = "fsl,mpc8360mds-bcsr";
reg = <1 0 0x8000>;
ranges = <0 1 0 0x8000>;
bcsr13: gpio-controller@d {
#gpio-cells = <2>;
compatible = "fsl,mpc8360mds-bcsr-gpio";
reg = <0xd 1>;
gpio-controller;
};
};

2
Documentation/s390/Debugging390.txt
View File

@ -1402,7 +1402,7 @@ Syscalls are implemented on Linux for S390 by the Supervisor call instruction (S
possibilities of these as the instruction is made up of a 0xA opcode & the second byte being
the syscall number. They are traced using the simple command.
TR SVC <Optional value or range>
the syscalls are defined in linux/include/asm-s390/unistd.h
the syscalls are defined in linux/arch/s390/include/asm/unistd.h
e.g. to trace all file opens just do
TR SVC 5 ( as this is the syscall number of open )

2
Documentation/s390/cds.txt
View File

@ -98,7 +98,7 @@ platform. Some of the interface routines are specific to Linux/390 and some
of them can be found on other Linux platforms implementations too.
Miscellaneous function prototypes, data declarations, and macro definitions
can be found in the architecture specific C header file
linux/include/asm-s390/irq.h.
linux/arch/s390/include/asm/irq.h.
Overview of CDS interface concepts

2
Documentation/s390/s390dbf.txt
View File

@ -2,7 +2,7 @@ S390 Debug Feature
==================
files: arch/s390/kernel/debug.c
include/asm-s390/debug.h
arch/s390/include/asm/debug.h
Description:
------------

2
Documentation/scsi/ChangeLog.lpfc
View File

@ -733,7 +733,7 @@ Changes from 20040920 to 20041018
I/O completion path a little more, especially taking care of
fast-pathing the non-error case. Also removes tons of dead
members and defines from lpfc_scsi.h - e.g. lpfc_target is down
to nothing more then the lpfc_nodelist pointer.
to nothing more than the lpfc_nodelist pointer.
* Added binary sysfs file to issue mbox commands
* Replaced #if __BIG_ENDIAN with #if __BIG_ENDIAN_BITFIELD for
compatibility with the user space applications.

2
Documentation/scsi/ChangeLog.ncr53c8xx
View File

@ -19,7 +19,7 @@ Sun Sep 24 21:30 2000 Gerard Roudier (groudier@club-internet.fr)
Wed Jul 26 23:30 2000 Gerard Roudier (groudier@club-internet.fr)
* version ncr53c8xx-3.4.1
- Provide OpenFirmare path through the proc FS on PPC.
- Provide OpenFirmware path through the proc FS on PPC.
- Remove trailing argument #2 from a couple of #undefs.
Sun Jul 09 16:30 2000 Gerard Roudier (groudier@club-internet.fr)

2
Documentation/scsi/ChangeLog.sym53c8xx
View File

@ -81,7 +81,7 @@ Sun Sep 24 21:30 2000 Gerard Roudier (groudier@club-internet.fr)
Wed Jul 26 23:30 2000 Gerard Roudier (groudier@club-internet.fr)
* version sym53c8xx-1.7.1
- Provide OpenFirmare path through the proc FS on PPC.
- Provide OpenFirmware path through the proc FS on PPC.
- Download of on-chip SRAM using memcpy_toio() doesn't work
on PPC. Restore previous method (MEMORY MOVE from SCRIPTS).
- Remove trailing argument #2 from a couple of #undefs.

85
Documentation/scsi/cxgb3i.txt Normal file
View File

@ -0,0 +1,85 @@
Chelsio S3 iSCSI Driver for Linux
Introduction
============
The Chelsio T3 ASIC based Adapters (S310, S320, S302, S304, Mezz cards, etc.
series of products) supports iSCSI acceleration and iSCSI Direct Data Placement
(DDP) where the hardware handles the expensive byte touching operations, such
as CRC computation and verification, and direct DMA to the final host memory
destination:
- iSCSI PDU digest generation and verification
On transmitting, Chelsio S3 h/w computes and inserts the Header and
Data digest into the PDUs.
On receiving, Chelsio S3 h/w computes and verifies the Header and
Data digest of the PDUs.
- Direct Data Placement (DDP)
S3 h/w can directly place the iSCSI Data-In or Data-Out PDU's
payload into pre-posted final destination host-memory buffers based
on the Initiator Task Tag (ITT) in Data-In or Target Task Tag (TTT)
in Data-Out PDUs.
- PDU Transmit and Recovery
On transmitting, S3 h/w accepts the complete PDU (header + data)
from the host driver, computes and inserts the digests, decomposes
the PDU into multiple TCP segments if necessary, and transmit all
the TCP segments onto the wire. It handles TCP retransmission if
needed.
On receving, S3 h/w recovers the iSCSI PDU by reassembling TCP
segments, separating the header and data, calculating and verifying
the digests, then forwards the header to the host. The payload data,
if possible, will be directly placed into the pre-posted host DDP
buffer. Otherwise, the payload data will be sent to the host too.
The cxgb3i driver interfaces with open-iscsi initiator and provides the iSCSI
acceleration through Chelsio hardware wherever applicable.
Using the cxgb3i Driver
=======================
The following steps need to be taken to accelerates the open-iscsi initiator:
1. Load the cxgb3i driver: "modprobe cxgb3i"
The cxgb3i module registers a new transport class "cxgb3i" with open-iscsi.
* in the case of recompiling the kernel, the cxgb3i selection is located at
Device Drivers
SCSI device support --->
[*] SCSI low-level drivers --->
<M> Chelsio S3xx iSCSI support
2. Create an interface file located under /etc/iscsi/ifaces/ for the new
transport class "cxgb3i".
The content of the file should be in the following format:
iface.transport_name = cxgb3i
iface.net_ifacename = <ethX>
iface.ipaddress = <iscsi ip address>
* if iface.ipaddress is specified, <iscsi ip address> needs to be either the
same as the ethX's ip address or an address on the same subnet. Make
sure the ip address is unique in the network.
3. edit /etc/iscsi/iscsid.conf
The default setting for MaxRecvDataSegmentLength (131072) is too big,
replace "node.conn[0].iscsi.MaxRecvDataSegmentLength" to be a value no
bigger than 15360 (for example 8192):
node.conn[0].iscsi.MaxRecvDataSegmentLength = 8192
* The login would fail for a normal session if MaxRecvDataSegmentLength is
too big. A error message in the format of
"cxgb3i: ERR! MaxRecvSegmentLength <X> too big. Need to be <= <Y>."
would be logged to dmesg.
4. To direct open-iscsi traffic to go through cxgb3i's accelerated path,
"-I <iface file name>" option needs to be specified with most of the
iscsiadm command. <iface file name> is the transport interface file created
in step 2.

4
Documentation/scsi/scsi_fc_transport.txt
View File

@ -191,7 +191,7 @@ Vport States:
This is equivalent to a driver "attach" on an adapter, which is
independent of the adapter's link state.
- Instantiation of the vport on the FC link via ELS traffic, etc.
This is equivalent to a "link up" and successfull link initialization.
This is equivalent to a "link up" and successful link initialization.
Further information can be found in the interfaces section below for
Vport Creation.
@ -320,7 +320,7 @@ Vport Creation:
This is equivalent to a driver "attach" on an adapter, which is
independent of the adapter's link state.
- Instantiation of the vport on the FC link via ELS traffic, etc.
This is equivalent to a "link up" and successfull link initialization.
This is equivalent to a "link up" and successful link initialization.
The LLDD's vport_create() function will not synchronously wait for both
parts to be fully completed before returning. It must validate that the

10
Documentation/spi/spi-lm70llp
View File

@ -13,10 +13,20 @@ Description
This driver provides glue code connecting a National Semiconductor LM70 LLP
temperature sensor evaluation board to the kernel's SPI core subsystem.
This is a SPI master controller driver. It can be used in conjunction with
(layered under) the LM70 logical driver (a "SPI protocol driver").
In effect, this driver turns the parallel port interface on the eval board
into a SPI bus with a single device, which will be driven by the generic
LM70 driver (drivers/hwmon/lm70.c).
Hardware Interfacing
--------------------
The schematic for this particular board (the LM70EVAL-LLP) is
available (on page 4) here:
http://www.national.com/appinfo/tempsensors/files/LM70LLPEVALmanual.pdf
The hardware interfacing on the LM70 LLP eval board is as follows:
Parallel LM70 LLP

21
Documentation/sysctl/vm.txt
View File

@ -38,10 +38,12 @@ Currently, these files are in /proc/sys/vm:
- numa_zonelist_order
- nr_hugepages
- nr_overcommit_hugepages
- nr_trim_pages (only if CONFIG_MMU=n)
==============================================================
dirty_ratio, dirty_background_ratio, dirty_expire_centisecs,
dirty_bytes, dirty_ratio, dirty_background_bytes,
dirty_background_ratio, dirty_expire_centisecs,
dirty_writeback_centisecs, highmem_is_dirtyable,
vfs_cache_pressure, laptop_mode, block_dump, swap_token_timeout,
drop-caches, hugepages_treat_as_movable:
@ -347,3 +349,20 @@ Change the maximum size of the hugepage pool. The maximum is
nr_hugepages + nr_overcommit_hugepages.
See Documentation/vm/hugetlbpage.txt
==============================================================
nr_trim_pages
This is available only on NOMMU kernels.
This value adjusts the excess page trimming behaviour of power-of-2 aligned
NOMMU mmap allocations.
A value of 0 disables trimming of allocations entirely, while a value of 1
trims excess pages aggressively. Any value >= 1 acts as the watermark where
trimming of allocations is initiated.
The default value is 1.
See Documentation/nommu-mmap.txt for more information.

22
Documentation/usb/power-management.txt
View File

@ -313,11 +313,13 @@ three of the methods listed above. In addition, a driver indicates
that it supports autosuspend by setting the .supports_autosuspend flag
in its usb_driver structure. It is then responsible for informing the
USB core whenever one of its interfaces becomes busy or idle. The
driver does so by calling these three functions:
driver does so by calling these five functions:
int usb_autopm_get_interface(struct usb_interface *intf);
void usb_autopm_put_interface(struct usb_interface *intf);
int usb_autopm_set_interface(struct usb_interface *intf);
int usb_autopm_get_interface_async(struct usb_interface *intf);
void usb_autopm_put_interface_async(struct usb_interface *intf);
The functions work by maintaining a counter in the usb_interface
structure. When intf->pm_usage_count is > 0 then the interface is
@ -330,10 +332,12 @@ associated with the device itself rather than any of its interfaces.
This field is used only by the USB core.)
The driver owns intf->pm_usage_count; it can modify the value however
and whenever it likes. A nice aspect of the usb_autopm_* routines is
that the changes they make are protected by the usb_device structure's
PM mutex (udev->pm_mutex); however drivers may change pm_usage_count
without holding the mutex.
and whenever it likes. A nice aspect of the non-async usb_autopm_*
routines is that the changes they make are protected by the usb_device
structure's PM mutex (udev->pm_mutex); however drivers may change
pm_usage_count without holding the mutex. Drivers using the async
routines are responsible for their own synchronization and mutual
exclusion.
usb_autopm_get_interface() increments pm_usage_count and
attempts an autoresume if the new value is > 0 and the
@ -348,6 +352,14 @@ without holding the mutex.
is suspended, and it attempts an autosuspend if the value is
<= 0 and the device isn't suspended.
usb_autopm_get_interface_async() and
usb_autopm_put_interface_async() do almost the same things as
their non-async counterparts. The differences are: they do
not acquire the PM mutex, and they use a workqueue to do their
jobs. As a result they can be called in an atomic context,
such as an URB's completion handler, but when they return the
device will not generally not yet be in the desired state.
There also are a couple of utility routines drivers can use:
usb_autopm_enable() sets pm_usage_cnt to 0 and then calls

9
Documentation/usb/wusb-cbaf
View File

@ -80,12 +80,6 @@ case $1 in
start)
for dev in ${2:-$hdevs}
do
uwb_rc=$(readlink -f $dev/uwb_rc)
if cat $uwb_rc/beacon | grep -q -- "-1"
then
echo 13 0 > $uwb_rc/beacon
echo I: started beaconing on ch 13 on $(basename $uwb_rc) >&2
fi
echo $host_CHID > $dev/wusb_chid
echo I: started host $(basename $dev) >&2
done
@ -95,9 +89,6 @@ case $1 in
do
echo 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > $dev/wusb_chid
echo I: stopped host $(basename $dev) >&2
uwb_rc=$(readlink -f $dev/uwb_rc)
echo -1 | cat > $uwb_rc/beacon
echo I: stopped beaconing on $(basename $uwb_rc) >&2
done
;;
set-chid)

43
Documentation/video4linux/API.html
View File

@ -1,16 +1,27 @@
<TITLE>V4L API</TITLE>
<H1>Video For Linux APIs</H1>
<table border=0>
<tr>
<td>
<A HREF=http://www.linuxtv.org/downloads/video4linux/API/V4L1_API.html>
V4L original API</a>
</td><td>
Obsoleted by V4L2 API
</td></tr><tr><td>
<A HREF=http://www.linuxtv.org/downloads/video4linux/API/V4L2_API>
V4L2 API</a>
</td><td>
Should be used for new projects
</td></tr>
</table>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<meta content="text/html;charset=ISO-8859-2" http-equiv="Content-Type" />
<title>V4L API</title>
</head>
<body>
<h1>Video For Linux APIs</h1>
<table border="0">
<tr>
<td>
<a href="http://www.linuxtv.org/downloads/video4linux/API/V4L1_API.html">V4L original API</a>
</td>
<td>
Obsoleted by V4L2 API
</td>
</tr>
<tr>
<td>
<a href="http://www.linuxtv.org/downloads/video4linux/API/V4L2_API">V4L2 API</a>
</td>
<td>Should be used for new projects
</td>
</tr>
</table>
</body>
</html>

7
Documentation/video4linux/CARDLIST.bttv
View File

@ -104,8 +104,8 @@
103 -> Grand X-Guard / Trust 814PCI [0304:0102]
104 -> Nebula Electronics DigiTV [0071:0101]
105 -> ProVideo PV143 [aa00:1430,aa00:1431,aa00:1432,aa00:1433,aa03:1433]
106 -> PHYTEC VD-009-X1 MiniDIN (bt878)
107 -> PHYTEC VD-009-X1 Combi (bt878)
106 -> PHYTEC VD-009-X1 VD-011 MiniDIN (bt878)
107 -> PHYTEC VD-009-X1 VD-011 Combi (bt878)
108 -> PHYTEC VD-009 MiniDIN (bt878)
109 -> PHYTEC VD-009 Combi (bt878)
110 -> IVC-100 [ff00:a132]
@ -151,3 +151,6 @@
150 -> Geovision GV-600 [008a:763c]
151 -> Kozumi KTV-01C
152 -> Encore ENL TV-FM-2 [1000:1801]
153 -> PHYTEC VD-012 (bt878)
154 -> PHYTEC VD-012-X1 (bt878)
155 -> PHYTEC VD-012-X2 (bt878)

1
Documentation/video4linux/CARDLIST.cx23885
View File

@ -11,3 +11,4 @@
10 -> DViCO FusionHDTV7 Dual Express [18ac:d618]
11 -> DViCO FusionHDTV DVB-T Dual Express [18ac:db78]
12 -> Leadtek Winfast PxDVR3200 H [107d:6681]
13 -> Compro VideoMate E650F [185b:e800]

5
Documentation/video4linux/CARDLIST.cx88
View File

@ -2,7 +2,7 @@
1 -> Hauppauge WinTV 34xxx models [0070:3400,0070:3401]
2 -> GDI Black Gold [14c7:0106,14c7:0107]
3 -> PixelView [1554:4811]
4 -> ATI TV Wonder Pro [1002:00f8]
4 -> ATI TV Wonder Pro [1002:00f8,1002:00f9]
5 -> Leadtek Winfast 2000XP Expert [107d:6611,107d:6613]
6 -> AverTV Studio 303 (M126) [1461:000b]
7 -> MSI TV-@nywhere Master [1462:8606]
@ -74,3 +74,6 @@
73 -> TeVii S420 DVB-S [d420:9022]
74 -> Prolink Pixelview Global Extreme [1554:4976]
75 -> PROF 7300 DVB-S/S2 [B033:3033]
76 -> SATTRADE ST4200 DVB-S/S2 [b200:4200]
77 -> TBS 8910 DVB-S [8910:8888]
78 -> Prof 6200 DVB-S [b022:3022]

9
Documentation/video4linux/CARDLIST.em28xx
View File

@ -1,5 +1,5 @@
0 -> Unknown EM2800 video grabber (em2800) [eb1a:2800]
1 -> Unknown EM2750/28xx video grabber (em2820/em2840) [eb1a:2820,eb1a:2860,eb1a:2861,eb1a:2870,eb1a:2881,eb1a:2883]
1 -> Unknown EM2750/28xx video grabber (em2820/em2840) [eb1a:2820,eb1a:2821,eb1a:2860,eb1a:2861,eb1a:2870,eb1a:2881,eb1a:2883]
2 -> Terratec Cinergy 250 USB (em2820/em2840) [0ccd:0036]
3 -> Pinnacle PCTV USB 2 (em2820/em2840) [2304:0208]
4 -> Hauppauge WinTV USB 2 (em2820/em2840) [2040:4200,2040:4201]
@ -12,9 +12,9 @@
11 -> Terratec Hybrid XS (em2880) [0ccd:0042]
12 -> Kworld PVR TV 2800 RF (em2820/em2840)
13 -> Terratec Prodigy XS (em2880) [0ccd:0047]
14 -> Pixelview Prolink PlayTV USB 2.0 (em2820/em2840) [eb1a:2821]
14 -> Pixelview Prolink PlayTV USB 2.0 (em2820/em2840)
15 -> V-Gear PocketTV (em2800)
16 -> Hauppauge WinTV HVR 950 (em2883) [2040:6513,2040:6517,2040:651b,2040:651f]
16 -> Hauppauge WinTV HVR 950 (em2883) [2040:6513,2040:6517,2040:651b]
17 -> Pinnacle PCTV HD Pro Stick (em2880) [2304:0227]
18 -> Hauppauge WinTV HVR 900 (R2) (em2880) [2040:6502]
19 -> PointNix Intra-Oral Camera (em2860)
@ -27,7 +27,6 @@
26 -> Hercules Smart TV USB 2.0 (em2820/em2840)
27 -> Pinnacle PCTV USB 2 (Philips FM1216ME) (em2820/em2840)
28 -> Leadtek Winfast USB II Deluxe (em2820/em2840)
29 -> Pinnacle Dazzle DVC 100 (em2820/em2840)
30 -> Videology 20K14XUSB USB2.0 (em2820/em2840)
31 -> Usbgear VD204v9 (em2821)
32 -> Supercomp USB 2.0 TV (em2821)
@ -57,3 +56,5 @@
56 -> Pinnacle Hybrid Pro (2) (em2882) [2304:0226]
57 -> Kworld PlusTV HD Hybrid 330 (em2883) [eb1a:a316]
58 -> Compro VideoMate ForYou/Stereo (em2820/em2840) [185b:2041]
60 -> Hauppauge WinTV HVR 850 (em2883) [2040:651f]
61 -> Pixelview PlayTV Box 4 USB 2.0 (em2820/em2840)

4
Documentation/video4linux/CARDLIST.saa7134
View File

@ -10,7 +10,7 @@
9 -> Medion 5044
10 -> Kworld/KuroutoShikou SAA7130-TVPCI
11 -> Terratec Cinergy 600 TV [153b:1143]
12 -> Medion 7134 [16be:0003]
12 -> Medion 7134 [16be:0003,16be:5000]
13 -> Typhoon TV+Radio 90031
14 -> ELSA EX-VISION 300TV [1048:226b]
15 -> ELSA EX-VISION 500TV [1048:226a]
@ -151,3 +151,5 @@
150 -> Zogis Real Angel 220
151 -> ADS Tech Instant HDTV [1421:0380]
152 -> Asus Tiger Rev:1.00 [1043:4857]
153 -> Kworld Plus TV Analog Lite PCI [17de:7128]
154 -> Avermedia AVerTV GO 007 FM Plus [1461:f31d]

8
Documentation/video4linux/README.cx88
View File

@ -1,4 +1,3 @@
cx8800 release notes
====================
@ -10,21 +9,20 @@ current status
video
- Basically works.
- Some minor image quality glitches.
- For now only capture, overlay support isn't completed yet.
- For now, only capture and read(). Overlay isn't supported.
audio
- The chip specs for the on-chip TV sound decoder are next
to useless :-/
- Neverless the builtin TV sound decoder starts working now,
at least for PAL-BG. Other TV norms need other code ...
at least for some standards.
FOR ANY REPORTS ON THIS PLEASE MENTION THE TV NORM YOU ARE
USING.
- Most tuner chips do provide mono sound, which may or may not
be useable depending on the board design. With the Hauppauge
cards it works, so there is mono sound available as fallback.
- audio data dma (i.e. recording without loopback cable to the
sound card) should be possible, but there is no code yet ...
sound card) is supported via cx88-alsa.
vbi
- Code present. Works for NTSC closed caption. PAL and other

19
Documentation/video4linux/gspca.txt
View File

@ -50,9 +50,14 @@ ov519 045e:028c Micro$oft xbox cam
spca508 0461:0815 Micro Innovation IC200
sunplus 0461:0821 Fujifilm MV-1
zc3xx 0461:0a00 MicroInnovation WebCam320
stv06xx 046d:0840 QuickCam Express
stv06xx 046d:0850 LEGO cam / QuickCam Web
stv06xx 046d:0870 Dexxa WebCam USB
spca500 046d:0890 Logitech QuickCam traveler
vc032x 046d:0892 Logitech Orbicam
vc032x 046d:0896 Logitech Orbicam
vc032x 046d:0897 Logitech QuickCam for Dell notebooks
zc3xx 046d:089d Logitech QuickCam E2500
zc3xx 046d:08a0 Logitech QC IM
zc3xx 046d:08a1 Logitech QC IM 0x08A1 +sound
zc3xx 046d:08a2 Labtec Webcam Pro
@ -169,6 +174,9 @@ spca500 06bd:0404 Agfa CL20
spca500 06be:0800 Optimedia
sunplus 06d6:0031 Trust 610 LCD PowerC@m Zoom
spca506 06e1:a190 ADS Instant VCD
ov534 06f8:3002 Hercules Blog Webcam
ov534 06f8:3003 Hercules Dualpix HD Weblog
sonixj 06f8:3004 Hercules Classic Silver
spca508 0733:0110 ViewQuest VQ110
spca508 0130:0130 Clone Digital Webcam 11043
spca501 0733:0401 Intel Create and Share
@ -199,7 +207,8 @@ sunplus 08ca:2050 Medion MD 41437
sunplus 08ca:2060 Aiptek PocketDV5300
tv8532 0923:010f ICM532 cams
mars 093a:050f Mars-Semi Pc-Camera
pac207 093a:2460 PAC207 Qtec Webcam 100
pac207 093a:2460 Qtec Webcam 100
pac207 093a:2461 HP Webcam
pac207 093a:2463 Philips SPC 220 NC
pac207 093a:2464 Labtec Webcam 1200
pac207 093a:2468 PAC207
@ -213,10 +222,13 @@ pac7311 093a:2603 PAC7312
pac7311 093a:2608 Trust WB-3300p
pac7311 093a:260e Gigaware VGA PC Camera, Trust WB-3350p, SIGMA cam 2350
pac7311 093a:260f SnakeCam
pac7311 093a:2620 Apollo AC-905
pac7311 093a:2621 PAC731x
pac7311 093a:2622 Genius Eye 312
pac7311 093a:2624 PAC7302
pac7311 093a:2626 Labtec 2200
pac7311 093a:262a Webcam 300k
pac7311 093a:262c Philips SPC 230 NC
zc3xx 0ac8:0302 Z-star Vimicro zc0302
vc032x 0ac8:0321 Vimicro generic vc0321
vc032x 0ac8:0323 Vimicro Vc0323
@ -249,11 +261,13 @@ sonixj 0c45:60c0 Sangha Sn535
sonixj 0c45:60ec SN9C105+MO4000
sonixj 0c45:60fb Surfer NoName
sonixj 0c45:60fc LG-LIC300
sonixj 0c45:60fe Microdia Audio
sonixj 0c45:6128 Microdia/Sonix SNP325
sonixj 0c45:612a Avant Camera
sonixj 0c45:612c Typhoon Rasy Cam 1.3MPix
sonixj 0c45:6130 Sonix Pccam
sonixj 0c45:6138 Sn9c120 Mo4000
sonixj 0c45:613a Microdia Sonix PC Camera
sonixj 0c45:613b Surfer SN-206
sonixj 0c45:613c Sonix Pccam168
sonixj 0c45:6143 Sonix Pccam168
@ -263,6 +277,9 @@ etoms 102c:6251 Qcam xxxxxx VGA
zc3xx 10fd:0128 Typhoon Webshot II USB 300k 0x0128
spca561 10fd:7e50 FlyCam Usb 100
zc3xx 10fd:8050 Typhoon Webshot II USB 300k
ov534 1415:2000 Sony HD Eye for PS3 (SLEH 00201)
pac207 145f:013a Trust WB-1300N
vc032x 15b8:6002 HP 2.0 Megapixel rz406aa
spca501 1776:501c Arowana 300K CMOS Camera
t613 17a1:0128 TASCORP JPEG Webcam, NGS Cyclops
vc032x 17ef:4802 Lenovo Vc0323+MI1310_SOC

1
Documentation/video4linux/si470x.txt
View File

@ -41,6 +41,7 @@ chips are known to work:
- 10c4:818a: Silicon Labs USB FM Radio Reference Design
- 06e1:a155: ADS/Tech FM Radio Receiver (formerly Instant FM Music) (RDX-155-EF)
- 1b80:d700: KWorld USB FM Radio SnapMusic Mobile 700 (FM700)
- 10c5:819a: DealExtreme USB Radio
Software

521
Documentation/video4linux/v4l2-framework.txt Normal file
View File

@ -0,0 +1,521 @@
Overview of the V4L2 driver framework
=====================================
This text documents the various structures provided by the V4L2 framework and
their relationships.
Introduction
------------
The V4L2 drivers tend to be very complex due to the complexity of the
hardware: most devices have multiple ICs, export multiple device nodes in
/dev, and create also non-V4L2 devices such as DVB, ALSA, FB, I2C and input
(IR) devices.
Especially the fact that V4L2 drivers have to setup supporting ICs to
do audio/video muxing/encoding/decoding makes it more complex than most.
Usually these ICs are connected to the main bridge driver through one or
more I2C busses, but other busses can also be used. Such devices are
called 'sub-devices'.
For a long time the framework was limited to the video_device struct for
creating V4L device nodes and video_buf for handling the video buffers
(note that this document does not discuss the video_buf framework).
This meant that all drivers had to do the setup of device instances and
connecting to sub-devices themselves. Some of this is quite complicated
to do right and many drivers never did do it correctly.
There is also a lot of common code that could never be refactored due to
the lack of a framework.
So this framework sets up the basic building blocks that all drivers
need and this same framework should make it much easier to refactor
common code into utility functions shared by all drivers.
Structure of a driver
---------------------
All drivers have the following structure:
1) A struct for each device instance containing the device state.
2) A way of initializing and commanding sub-devices (if any).
3) Creating V4L2 device nodes (/dev/videoX, /dev/vbiX, /dev/radioX and
/dev/vtxX) and keeping track of device-node specific data.
4) Filehandle-specific structs containing per-filehandle data.
This is a rough schematic of how it all relates:
device instances
|
+-sub-device instances
|
\-V4L2 device nodes
|
\-filehandle instances
Structure of the framework
--------------------------
The framework closely resembles the driver structure: it has a v4l2_device
struct for the device instance data, a v4l2_subdev struct to refer to
sub-device instances, the video_device struct stores V4L2 device node data
and in the future a v4l2_fh struct will keep track of filehandle instances
(this is not yet implemented).
struct v4l2_device
------------------
Each device instance is represented by a struct v4l2_device (v4l2-device.h).
Very simple devices can just allocate this struct, but most of the time you
would embed this struct inside a larger struct.
You must register the device instance:
v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev);
Registration will initialize the v4l2_device struct and link dev->driver_data
to v4l2_dev. Registration will also set v4l2_dev->name to a value derived from
dev (driver name followed by the bus_id, to be precise). You may change the
name after registration if you want.
The first 'dev' argument is normally the struct device pointer of a pci_dev,
usb_device or platform_device.
You unregister with:
v4l2_device_unregister(struct v4l2_device *v4l2_dev);
Unregistering will also automatically unregister all subdevs from the device.
Sometimes you need to iterate over all devices registered by a specific
driver. This is usually the case if multiple device drivers use the same
hardware. E.g. the ivtvfb driver is a framebuffer driver that uses the ivtv
hardware. The same is true for alsa drivers for example.
You can iterate over all registered devices as follows:
static int callback(struct device *dev, void *p)
{
struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
/* test if this device was inited */
if (v4l2_dev == NULL)
return 0;
...
return 0;
}
int iterate(void *p)
{
struct device_driver *drv;
int err;
/* Find driver 'ivtv' on the PCI bus.
pci_bus_type is a global. For USB busses use usb_bus_type. */
drv = driver_find("ivtv", &pci_bus_type);
/* iterate over all ivtv device instances */
err = driver_for_each_device(drv, NULL, p, callback);
put_driver(drv);
return err;
}
Sometimes you need to keep a running counter of the device instance. This is
commonly used to map a device instance to an index of a module option array.
The recommended approach is as follows:
static atomic_t drv_instance = ATOMIC_INIT(0);
static int __devinit drv_probe(struct pci_dev *dev,
const struct pci_device_id *pci_id)
{
...
state->instance = atomic_inc_return(&drv_instance) - 1;
}
struct v4l2_subdev
------------------
Many drivers need to communicate with sub-devices. These devices can do all
sort of tasks, but most commonly they handle audio and/or video muxing,
encoding or decoding. For webcams common sub-devices are sensors and camera
controllers.
Usually these are I2C devices, but not necessarily. In order to provide the
driver with a consistent interface to these sub-devices the v4l2_subdev struct
(v4l2-subdev.h) was created.
Each sub-device driver must have a v4l2_subdev struct. This struct can be
stand-alone for simple sub-devices or it might be embedded in a larger struct
if more state information needs to be stored. Usually there is a low-level
device struct (e.g. i2c_client) that contains the device data as setup
by the kernel. It is recommended to store that pointer in the private
data of v4l2_subdev using v4l2_set_subdevdata(). That makes it easy to go
from a v4l2_subdev to the actual low-level bus-specific device data.
You also need a way to go from the low-level struct to v4l2_subdev. For the
common i2c_client struct the i2c_set_clientdata() call is used to store a
v4l2_subdev pointer, for other busses you may have to use other methods.
From the bridge driver perspective you load the sub-device module and somehow
obtain the v4l2_subdev pointer. For i2c devices this is easy: you call
i2c_get_clientdata(). For other busses something similar needs to be done.
Helper functions exists for sub-devices on an I2C bus that do most of this
tricky work for you.
Each v4l2_subdev contains function pointers that sub-device drivers can
implement (or leave NULL if it is not applicable). Since sub-devices can do
so many different things and you do not want to end up with a huge ops struct
of which only a handful of ops are commonly implemented, the function pointers
are sorted according to category and each category has its own ops struct.
The top-level ops struct contains pointers to the category ops structs, which
may be NULL if the subdev driver does not support anything from that category.
It looks like this:
struct v4l2_subdev_core_ops {
int (*g_chip_ident)(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip);
int (*log_status)(struct v4l2_subdev *sd);
int (*init)(struct v4l2_subdev *sd, u32 val);
...
};
struct v4l2_subdev_tuner_ops {
...
};
struct v4l2_subdev_audio_ops {
...
};
struct v4l2_subdev_video_ops {
...
};
struct v4l2_subdev_ops {
const struct v4l2_subdev_core_ops *core;
const struct v4l2_subdev_tuner_ops *tuner;
const struct v4l2_subdev_audio_ops *audio;
const struct v4l2_subdev_video_ops *video;
};
The core ops are common to all subdevs, the other categories are implemented
depending on the sub-device. E.g. a video device is unlikely to support the
audio ops and vice versa.
This setup limits the number of function pointers while still making it easy
to add new ops and categories.
A sub-device driver initializes the v4l2_subdev struct using:
v4l2_subdev_init(subdev, &ops);
Afterwards you need to initialize subdev->name with a unique name and set the
module owner. This is done for you if you use the i2c helper functions.
A device (bridge) driver needs to register the v4l2_subdev with the
v4l2_device:
int err = v4l2_device_register_subdev(device, subdev);
This can fail if the subdev module disappeared before it could be registered.
After this function was called successfully the subdev->dev field points to
the v4l2_device.
You can unregister a sub-device using:
v4l2_device_unregister_subdev(subdev);
Afterwards the subdev module can be unloaded and subdev->dev == NULL.
You can call an ops function either directly:
err = subdev->ops->core->g_chip_ident(subdev, &chip);
but it is better and easier to use this macro:
err = v4l2_subdev_call(subdev, core, g_chip_ident, &chip);
The macro will to the right NULL pointer checks and returns -ENODEV if subdev
is NULL, -ENOIOCTLCMD if either subdev->core or subdev->core->g_chip_ident is
NULL, or the actual result of the subdev->ops->core->g_chip_ident ops.
It is also possible to call all or a subset of the sub-devices:
v4l2_device_call_all(dev, 0, core, g_chip_ident, &chip);
Any subdev that does not support this ops is skipped and error results are
ignored. If you want to check for errors use this:
err = v4l2_device_call_until_err(dev, 0, core, g_chip_ident, &chip);
Any error except -ENOIOCTLCMD will exit the loop with that error. If no
errors (except -ENOIOCTLCMD) occured, then 0 is returned.
The second argument to both calls is a group ID. If 0, then all subdevs are
called. If non-zero, then only those whose group ID match that value will
be called. Before a bridge driver registers a subdev it can set subdev->grp_id
to whatever value it wants (it's 0 by default). This value is owned by the
bridge driver and the sub-device driver will never modify or use it.
The group ID gives the bridge driver more control how callbacks are called.
For example, there may be multiple audio chips on a board, each capable of
changing the volume. But usually only one will actually be used when the
user want to change the volume. You can set the group ID for that subdev to
e.g. AUDIO_CONTROLLER and specify that as the group ID value when calling
v4l2_device_call_all(). That ensures that it will only go to the subdev
that needs it.
The advantage of using v4l2_subdev is that it is a generic struct and does
not contain any knowledge about the underlying hardware. So a driver might
contain several subdevs that use an I2C bus, but also a subdev that is
controlled through GPIO pins. This distinction is only relevant when setting
up the device, but once the subdev is registered it is completely transparent.
I2C sub-device drivers
----------------------
Since these drivers are so common, special helper functions are available to
ease the use of these drivers (v4l2-common.h).
The recommended method of adding v4l2_subdev support to an I2C driver is to
embed the v4l2_subdev struct into the state struct that is created for each
I2C device instance. Very simple devices have no state struct and in that case
you can just create a v4l2_subdev directly.
A typical state struct would look like this (where 'chipname' is replaced by
the name of the chip):
struct chipname_state {
struct v4l2_subdev sd;
... /* additional state fields */
};
Initialize the v4l2_subdev struct as follows:
v4l2_i2c_subdev_init(&state->sd, client, subdev_ops);
This function will fill in all the fields of v4l2_subdev and ensure that the
v4l2_subdev and i2c_client both point to one another.
You should also add a helper inline function to go from a v4l2_subdev pointer
to a chipname_state struct:
static inline struct chipname_state *to_state(struct v4l2_subdev *sd)
{
return container_of(sd, struct chipname_state, sd);
}
Use this to go from the v4l2_subdev struct to the i2c_client struct:
struct i2c_client *client = v4l2_get_subdevdata(sd);
And this to go from an i2c_client to a v4l2_subdev struct:
struct v4l2_subdev *sd = i2c_get_clientdata(client);
Finally you need to make a command function to make driver->command()
call the right subdev_ops functions:
static int subdev_command(struct i2c_client *client, unsigned cmd, void *arg)
{
return v4l2_subdev_command(i2c_get_clientdata(client), cmd, arg);
}
If driver->command is never used then you can leave this out. Eventually the
driver->command usage should be removed from v4l.
Make sure to call v4l2_device_unregister_subdev(sd) when the remove() callback
is called. This will unregister the sub-device from the bridge driver. It is
safe to call this even if the sub-device was never registered.
The bridge driver also has some helper functions it can use:
struct v4l2_subdev *sd = v4l2_i2c_new_subdev(adapter, "module_foo", "chipid", 0x36);
This loads the given module (can be NULL if no module needs to be loaded) and
calls i2c_new_device() with the given i2c_adapter and chip/address arguments.
If all goes well, then it registers the subdev with the v4l2_device. It gets
the v4l2_device by calling i2c_get_adapdata(adapter), so you should make sure
that adapdata is set to v4l2_device when you setup the i2c_adapter in your
driver.
You can also use v4l2_i2c_new_probed_subdev() which is very similar to
v4l2_i2c_new_subdev(), except that it has an array of possible I2C addresses
that it should probe. Internally it calls i2c_new_probed_device().
Both functions return NULL if something went wrong.
struct video_device
-------------------
The actual device nodes in the /dev directory are created using the
video_device struct (v4l2-dev.h). This struct can either be allocated
dynamically or embedded in a larger struct.
To allocate it dynamically use:
struct video_device *vdev = video_device_alloc();
if (vdev == NULL)
return -ENOMEM;
vdev->release = video_device_release;
If you embed it in a larger struct, then you must set the release()
callback to your own function:
struct video_device *vdev = &my_vdev->vdev;
vdev->release = my_vdev_release;
The release callback must be set and it is called when the last user
of the video device exits.
The default video_device_release() callback just calls kfree to free the
allocated memory.
You should also set these fields:
- v4l2_dev: set to the v4l2_device parent device.
- name: set to something descriptive and unique.
- fops: set to the v4l2_file_operations struct.
- ioctl_ops: if you use the v4l2_ioctl_ops to simplify ioctl maintenance
(highly recommended to use this and it might become compulsory in the
future!), then set this to your v4l2_ioctl_ops struct.
If you use v4l2_ioctl_ops, then you should set either .unlocked_ioctl or
.ioctl to video_ioctl2 in your v4l2_file_operations struct.
The v4l2_file_operations struct is a subset of file_operations. The main
difference is that the inode argument is omitted since it is never used.
video_device registration
-------------------------
Next you register the video device: this will create the character device
for you.
err = video_register_device(vdev, VFL_TYPE_GRABBER, -1);
if (err) {
video_device_release(vdev); /* or kfree(my_vdev); */
return err;
}
Which device is registered depends on the type argument. The following
types exist:
VFL_TYPE_GRABBER: videoX for video input/output devices
VFL_TYPE_VBI: vbiX for vertical blank data (i.e. closed captions, teletext)
VFL_TYPE_RADIO: radioX for radio tuners
VFL_TYPE_VTX: vtxX for teletext devices (deprecated, don't use)
The last argument gives you a certain amount of control over the device
kernel number used (i.e. the X in videoX). Normally you will pass -1 to
let the v4l2 framework pick the first free number. But if a driver creates
many devices, then it can be useful to have different video devices in
separate ranges. For example, video capture devices start at 0, video
output devices start at 16.
So you can use the last argument to specify a minimum kernel number and
the v4l2 framework will try to pick the first free number that is equal
or higher to what you passed. If that fails, then it will just pick the
first free number.
Whenever a device node is created some attributes are also created for you.
If you look in /sys/class/video4linux you see the devices. Go into e.g.
video0 and you will see 'name' and 'index' attributes. The 'name' attribute
is the 'name' field of the video_device struct. The 'index' attribute is
a device node index that can be assigned by the driver, or that is calculated
for you.
If you call video_register_device(), then the index is just increased by
1 for each device node you register. The first video device node you register
always starts off with 0.
Alternatively you can call video_register_device_index() which is identical
to video_register_device(), but with an extra index argument. Here you can
pass a specific index value (between 0 and 31) that should be used.
Users can setup udev rules that utilize the index attribute to make fancy
device names (e.g. 'mpegX' for MPEG video capture device nodes).
After the device was successfully registered, then you can use these fields:
- vfl_type: the device type passed to video_register_device.
- minor: the assigned device minor number.
- num: the device kernel number (i.e. the X in videoX).
- index: the device index number (calculated or set explicitly using
video_register_device_index).
If the registration failed, then you need to call video_device_release()
to free the allocated video_device struct, or free your own struct if the
video_device was embedded in it. The vdev->release() callback will never
be called if the registration failed, nor should you ever attempt to
unregister the device if the registration failed.
video_device cleanup
--------------------
When the video device nodes have to be removed, either during the unload
of the driver or because the USB device was disconnected, then you should
unregister them:
video_unregister_device(vdev);
This will remove the device nodes from sysfs (causing udev to remove them
from /dev).
After video_unregister_device() returns no new opens can be done.
However, in the case of USB devices some application might still have one
of these device nodes open. You should block all new accesses to read,
write, poll, etc. except possibly for certain ioctl operations like
queueing buffers.
When the last user of the video device node exits, then the vdev->release()
callback is called and you can do the final cleanup there.
video_device helper functions
-----------------------------
There are a few useful helper functions:
You can set/get driver private data in the video_device struct using:
void *video_get_drvdata(struct video_device *dev);
void video_set_drvdata(struct video_device *dev, void *data);
Note that you can safely call video_set_drvdata() before calling
video_register_device().
And this function:
struct video_device *video_devdata(struct file *file);
returns the video_device belonging to the file struct.
The final helper function combines video_get_drvdata with
video_devdata:
void *video_drvdata(struct file *file);
You can go from a video_device struct to the v4l2_device struct using:
struct v4l2_device *v4l2_dev = vdev->v4l2_dev;

63
Documentation/vm/unevictable-lru.txt
View File

@ -137,13 +137,6 @@ shrink_page_list() where they will be detected when vmscan walks the reverse
map in try_to_unmap(). If try_to_unmap() returns SWAP_MLOCK, shrink_page_list()
will cull the page at that point.
Note that for anonymous pages, shrink_page_list() attempts to add the page to
the swap cache before it tries to unmap the page. To avoid this unnecessary
consumption of swap space, shrink_page_list() calls try_to_munlock() to check
whether any VM_LOCKED vmas map the page without attempting to unmap the page.
If try_to_munlock() returns SWAP_MLOCK, shrink_page_list() will cull the page
without consuming swap space. try_to_munlock() will be described below.
To "cull" an unevictable page, vmscan simply puts the page back on the lru
list using putback_lru_page()--the inverse operation to isolate_lru_page()--
after dropping the page lock. Because the condition which makes the page
@ -190,8 +183,8 @@ several places:
in the VM_LOCKED flag being set for the vma.
3) in the fault path, if mlocked pages are "culled" in the fault path,
and when a VM_LOCKED stack segment is expanded.
4) as mentioned above, in vmscan:shrink_page_list() with attempting to
reclaim a page in a VM_LOCKED vma--via try_to_unmap() or try_to_munlock().
4) as mentioned above, in vmscan:shrink_page_list() when attempting to
reclaim a page in a VM_LOCKED vma via try_to_unmap().
Mlocked pages become unlocked and rescued from the unevictable list when:
@ -260,9 +253,9 @@ mlock_fixup() filters several classes of "special" vmas:
2) vmas mapping hugetlbfs page are already effectively pinned into memory.
We don't need nor want to mlock() these pages. However, to preserve the
prior behavior of mlock()--before the unevictable/mlock changes--mlock_fixup()
will call make_pages_present() in the hugetlbfs vma range to allocate the
huge pages and populate the ptes.
prior behavior of mlock()--before the unevictable/mlock changes--
mlock_fixup() will call make_pages_present() in the hugetlbfs vma range
to allocate the huge pages and populate the ptes.
3) vmas with VM_DONTEXPAND|VM_RESERVED are generally user space mappings of
kernel pages, such as the vdso page, relay channel pages, etc. These pages
@ -322,7 +315,7 @@ __mlock_vma_pages_range()--the same function used to mlock a vma range--
passing a flag to indicate that munlock() is being performed.
Because the vma access protections could have been changed to PROT_NONE after
faulting in and mlocking some pages, get_user_pages() was unreliable for visiting
faulting in and mlocking pages, get_user_pages() was unreliable for visiting
these pages for munlocking. Because we don't want to leave pages mlocked(),
get_user_pages() was enhanced to accept a flag to ignore the permissions when
fetching the pages--all of which should be resident as a result of previous
@ -416,8 +409,8 @@ Mlocked Pages: munmap()/exit()/exec() System Call Handling
When unmapping an mlocked region of memory, whether by an explicit call to
munmap() or via an internal unmap from exit() or exec() processing, we must
munlock the pages if we're removing the last VM_LOCKED vma that maps the pages.
Before the unevictable/mlock changes, mlocking did not mark the pages in any way,
so unmapping them required no processing.
Before the unevictable/mlock changes, mlocking did not mark the pages in any
way, so unmapping them required no processing.
To munlock a range of memory under the unevictable/mlock infrastructure, the
munmap() hander and task address space tear down function call
@ -517,12 +510,10 @@ couldn't be mlocked.
Mlocked pages: try_to_munlock() Reverse Map Scan
TODO/FIXME: a better name might be page_mlocked()--analogous to the
page_referenced() reverse map walker--especially if we continue to call this
from shrink_page_list(). See related TODO/FIXME below.
page_referenced() reverse map walker.
When munlock_vma_page()--see "Mlocked Pages: munlock()/munlockall() System
Call Handling" above--tries to munlock a page, or when shrink_page_list()
encounters an anonymous page that is not yet in the swap cache, they need to
When munlock_vma_page()--see "Mlocked Pages: munlock()/munlockall()
System Call Handling" above--tries to munlock a page, it needs to
determine whether or not the page is mapped by any VM_LOCKED vma, without
actually attempting to unmap all ptes from the page. For this purpose, the
unevictable/mlock infrastructure introduced a variant of try_to_unmap() called
@ -535,10 +526,7 @@ for VM_LOCKED vmas. When such a vma is found for anonymous pages and file
pages mapped in linear VMAs, as in the try_to_unmap() case, the functions
attempt to acquire the associated mmap semphore, mlock the page via
mlock_vma_page() and return SWAP_MLOCK. This effectively undoes the
pre-clearing of the page's PG_mlocked done by munlock_vma_page() and informs
shrink_page_list() that the anonymous page should be culled rather than added
to the swap cache in preparation for a try_to_unmap() that will almost
certainly fail.
pre-clearing of the page's PG_mlocked done by munlock_vma_page.
If try_to_unmap() is unable to acquire a VM_LOCKED vma's associated mmap
semaphore, it will return SWAP_AGAIN. This will allow shrink_page_list()
@ -557,10 +545,7 @@ However, the scan can terminate when it encounters a VM_LOCKED vma and can
successfully acquire the vma's mmap semphore for read and mlock the page.
Although try_to_munlock() can be called many [very many!] times when
munlock()ing a large region or tearing down a large address space that has been
mlocked via mlockall(), overall this is a fairly rare event. In addition,
although shrink_page_list() calls try_to_munlock() for every anonymous page that
it handles that is not yet in the swap cache, on average anonymous pages will
have very short reverse map lists.
mlocked via mlockall(), overall this is a fairly rare event.
Mlocked Page: Page Reclaim in shrink_*_list()
@ -588,8 +573,8 @@ Some examples of these unevictable pages on the LRU lists are:
munlock_vma_page() was forced to let the page back on to the normal
LRU list for vmscan to handle.
shrink_inactive_list() also culls any unevictable pages that it finds
on the inactive lists, again diverting them to the appropriate zone's unevictable
shrink_inactive_list() also culls any unevictable pages that it finds on
the inactive lists, again diverting them to the appropriate zone's unevictable
lru list. shrink_inactive_list() should only see SHM_LOCKed pages that became
SHM_LOCKed after shrink_active_list() had moved them to the inactive list, or
pages mapped into VM_LOCKED vmas that munlock_vma_page() couldn't isolate from
@ -597,19 +582,7 @@ the lru to recheck via try_to_munlock(). shrink_inactive_list() won't notice
the latter, but will pass on to shrink_page_list().
shrink_page_list() again culls obviously unevictable pages that it could
encounter for similar reason to shrink_inactive_list(). As already discussed,
shrink_page_list() proactively looks for anonymous pages that should have
PG_mlocked set but don't--these would not be detected by page_evictable()--to
avoid adding them to the swap cache unnecessarily. File pages mapped into
encounter for similar reason to shrink_inactive_list(). Pages mapped into
VM_LOCKED vmas but without PG_mlocked set will make it all the way to
try_to_unmap(). shrink_page_list() will divert them to the unevictable list when
try_to_unmap() returns SWAP_MLOCK, as discussed above.
TODO/FIXME: If we can enhance the swap cache to reliably remove entries
with page_count(page) > 2, as long as all ptes are mapped to the page and
not the swap entry, we can probably remove the call to try_to_munlock() in
shrink_page_list() and just remove the page from the swap cache when
try_to_unmap() returns SWAP_MLOCK. Currently, remove_exclusive_swap_page()
doesn't seem to allow that.
try_to_unmap(). shrink_page_list() will divert them to the unevictable list
when try_to_unmap() returns SWAP_MLOCK, as discussed above.

2
Documentation/w1/masters/00-INDEX
View File

@ -4,5 +4,7 @@ ds2482
- The Maxim/Dallas Semiconductor DS2482 provides 1-wire busses.
ds2490
- The Maxim/Dallas Semiconductor DS2490 builds USB <-> W1 bridges.
mxc_w1
- W1 master controller driver found on Freescale MX2/MX3 SoCs
w1-gpio
- GPIO 1-wire bus master driver.

11
Documentation/w1/masters/mxc-w1 Normal file
View File

@ -0,0 +1,11 @@
Kernel driver mxc_w1
====================
Supported chips:
* Freescale MX27, MX31 and probably other i.MX SoCs
Datasheets:
http://www.freescale.com/files/32bit/doc/data_sheet/MCIMX31.pdf?fpsp=1
http://www.freescale.com/files/dsp/MCIMX27.pdf?fpsp=1
Author: Originally based on Freescale code, prepared for mainline by
Sascha Hauer <s.hauer@pengutronix.de>

164
Documentation/w1/w1.netlink
View File

@ -5,69 +5,157 @@ Message types.
=============
There are three types of messages between w1 core and userspace:
1. Events. They are generated each time new master or slave device found
either due to automatic or requested search.
2. Userspace commands. Includes read/write and search/alarm search comamnds.
1. Events. They are generated each time new master or slave device
found either due to automatic or requested search.
2. Userspace commands.
3. Replies to userspace commands.
Protocol.
========
[struct cn_msg] - connector header. It's length field is equal to size of the attached data.
[struct cn_msg] - connector header.
Its length field is equal to size of the attached data
[struct w1_netlink_msg] - w1 netlink header.
__u8 type - message type.
W1_SLAVE_ADD/W1_SLAVE_REMOVE - slave add/remove events.
W1_MASTER_ADD/W1_MASTER_REMOVE - master add/remove events.
W1_MASTER_CMD - userspace command for bus master device (search/alarm search).
W1_SLAVE_CMD - userspace command for slave device (read/write/ search/alarm search
for bus master device where given slave device found).
W1_LIST_MASTERS
list current bus masters
W1_SLAVE_ADD/W1_SLAVE_REMOVE
slave add/remove events
W1_MASTER_ADD/W1_MASTER_REMOVE
master add/remove events
W1_MASTER_CMD
userspace command for bus master
device (search/alarm search)
W1_SLAVE_CMD
userspace command for slave device
(read/write/touch)
__u8 res - reserved
__u16 len - size of attached to this header data.
__u16 len - size of data attached to this header data
union {
__u8 id; - slave unique device id
__u8 id[8]; - slave unique device id
struct w1_mst {
__u32 id; - master's id.
__u32 id; - master's id
__u32 res; - reserved
} mst;
} id;
[strucrt w1_netlink_cmd] - command for gived master or slave device.
[struct w1_netlink_cmd] - command for given master or slave device.
__u8 cmd - command opcode.
W1_CMD_READ - read command.
W1_CMD_WRITE - write command.
W1_CMD_SEARCH - search command.
W1_CMD_ALARM_SEARCH - alarm search command.
W1_CMD_READ - read command
W1_CMD_WRITE - write command
W1_CMD_TOUCH - touch command
(write and sample data back to userspace)
W1_CMD_SEARCH - search command
W1_CMD_ALARM_SEARCH - alarm search command
__u8 res - reserved
__u16 len - length of data for this command.
For read command data must be allocated like for write command.
__u8 data[0] - data for this command.
__u16 len - length of data for this command
For read command data must be allocated like for write command
__u8 data[0] - data for this command
Each connector message can include one or more w1_netlink_msg with zero of more attached w1_netlink_cmd messages.
Each connector message can include one or more w1_netlink_msg with
zero or more attached w1_netlink_cmd messages.
For event messages there are no w1_netlink_cmd embedded structures, only connector header
and w1_netlink_msg strucutre with "len" field being zero and filled type (one of event types)
and id - either 8 bytes of slave unique id in host order, or master's id, which is assigned
to bus master device when it is added to w1 core.
For event messages there are no w1_netlink_cmd embedded structures,
only connector header and w1_netlink_msg strucutre with "len" field
being zero and filled type (one of event types) and id:
either 8 bytes of slave unique id in host order,
or master's id, which is assigned to bus master device
when it is added to w1 core.
Currently replies to userspace commands are only generated for read
command request. One reply is generated exactly for one w1_netlink_cmd
read request. Replies are not combined when sent - i.e. typical reply
messages looks like the following:
Currently replies to userspace commands are only generated for read command request.
One reply is generated exactly for one w1_netlink_cmd read request.
Replies are not combined when sent - i.e. typical reply messages looks like the following:
[cn_msg][w1_netlink_msg][w1_netlink_cmd]
cn_msg.len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd) + cmd->len;
cn_msg.len = sizeof(struct w1_netlink_msg) +
sizeof(struct w1_netlink_cmd) +
cmd->len;
w1_netlink_msg.len = sizeof(struct w1_netlink_cmd) + cmd->len;
w1_netlink_cmd.len = cmd->len;
Replies to W1_LIST_MASTERS should send a message back to the userspace
which will contain list of all registered master ids in the following
format:
cn_msg (CN_W1_IDX.CN_W1_VAL as id, len is equal to sizeof(struct
w1_netlink_msg) plus number of masters multipled by 4)
w1_netlink_msg (type: W1_LIST_MASTERS, len is equal to
number of masters multiplied by 4 (u32 size))
id0 ... idN
Each message is at most 4k in size, so if number of master devices
exceeds this, it will be split into several messages,
cn.seq will be increased for each one.
W1 search and alarm search commands.
request:
[cn_msg]
[w1_netlink_msg type = W1_MASTER_CMD
id is equal to the bus master id to use for searching]
[w1_netlink_cmd cmd = W1_CMD_SEARCH or W1_CMD_ALARM_SEARCH]
reply:
[cn_msg, ack = 1 and increasing, 0 means the last message,
seq is equal to the request seq]
[w1_netlink_msg type = W1_MASTER_CMD]
[w1_netlink_cmd cmd = W1_CMD_SEARCH or W1_CMD_ALARM_SEARCH
len is equal to number of IDs multiplied by 8]
[64bit-id0 ... 64bit-idN]
Length in each header corresponds to the size of the data behind it, so
w1_netlink_cmd->len = N * 8; where N is number of IDs in this message.
Can be zero.
w1_netlink_msg->len = sizeof(struct w1_netlink_cmd) + N * 8;
cn_msg->len = sizeof(struct w1_netlink_msg) +
sizeof(struct w1_netlink_cmd) +
N*8;
W1 reset command.
[cn_msg]
[w1_netlink_msg type = W1_MASTER_CMD
id is equal to the bus master id to use for searching]
[w1_netlink_cmd cmd = W1_CMD_RESET]
Command status replies.
======================
Each command (either root, master or slave with or without w1_netlink_cmd
structure) will be 'acked' by the w1 core. Format of the reply is the same
as request message except that length parameters do not account for data
requested by the user, i.e. read/write/touch IO requests will not contain
data, so w1_netlink_cmd.len will be 0, w1_netlink_msg.len will be size
of the w1_netlink_cmd structure and cn_msg.len will be equal to the sum
of the sizeof(struct w1_netlink_msg) and sizeof(struct w1_netlink_cmd).
If reply is generated for master or root command (which do not have
w1_netlink_cmd attached), reply will contain only cn_msg and w1_netlink_msg
structires.
w1_netlink_msg.status field will carry positive error value
(EINVAL for example) or zero in case of success.
All other fields in every structure will mirror the same parameters in the
request message (except lengths as described above).
Status reply is generated for every w1_netlink_cmd embedded in the
w1_netlink_msg, if there are no w1_netlink_cmd structures,
reply will be generated for the w1_netlink_msg.
All w1_netlink_cmd command structures are handled in every w1_netlink_msg,
even if there were errors, only length mismatch interrupts message processing.
Operation steps in w1 core when new command is received.
=======================================================
When new message (w1_netlink_msg) is received w1 core detects if it is master of slave request,
according to w1_netlink_msg.type field.
When new message (w1_netlink_msg) is received w1 core detects if it is
master or slave request, according to w1_netlink_msg.type field.
Then master or slave device is searched for.
When found, master device (requested or those one on where slave device is found) is locked.
If slave command is requested, then reset/select procedure is started to select given device.
When found, master device (requested or those one on where slave device
is found) is locked. If slave command is requested, then reset/select
procedure is started to select given device.
Then all requested in w1_netlink_msg operations are performed one by one.
If command requires reply (like read command) it is sent on command completion.
@ -82,8 +170,8 @@ Connector [1] specific documentation.
Each connector message includes two u32 fields as "address".
w1 uses CN_W1_IDX and CN_W1_VAL defined in include/linux/connector.h header.
Each message also includes sequence and acknowledge numbers.
Sequence number for event messages is appropriate bus master sequence number increased with
each event message sent "through" this master.
Sequence number for event messages is appropriate bus master sequence number
increased with each event message sent "through" this master.
Sequence number for userspace requests is set by userspace application.
Sequence number for reply is the same as was in request, and
acknowledge number is set to seq+1.
@ -93,6 +181,6 @@ Additional documantion, source code examples.
============================================
1. Documentation/connector
2. http://tservice.net.ru/~s0mbre/archive/w1
This archive includes userspace application w1d.c which
uses read/write/search commands for all master/slave devices found on the bus.
2. http://www.ioremap.net/archive/w1
This archive includes userspace application w1d.c which uses
read/write/search commands for all master/slave devices found on the bus.

260
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@ -0,0 +1,260 @@
Driver for the Intel Wireless Wimax Connection 2400m
(C) 2008 Intel Corporation < linux-wimax@intel.com >
This provides a driver for the Intel Wireless WiMAX Connection 2400m
and a basic Linux kernel WiMAX stack.
1. Requirements
* Linux installation with Linux kernel 2.6.22 or newer (if building
from a separate tree)
* Intel i2400m Echo Peak or Baxter Peak; this includes the Intel
Wireless WiMAX/WiFi Link 5x50 series.
* build tools:
+ Linux kernel development package for the target kernel; to
build against your currently running kernel, you need to have
the kernel development package corresponding to the running
image installed (usually if your kernel is named
linux-VERSION, the development package is called
linux-dev-VERSION or linux-headers-VERSION).
+ GNU C Compiler, make
2. Compilation and installation
2.1. Compilation of the drivers included in the kernel
Configure the kernel; to enable the WiMAX drivers select Drivers >
Networking Drivers > WiMAX device support. Enable all of them as
modules (easier).
If USB or SDIO are not enabled in the kernel configuration, the options
to build the i2400m USB or SDIO drivers will not show. Enable said
subsystems and go back to the WiMAX menu to enable the drivers.
Compile and install your kernel as usual.
2.2. Compilation of the drivers distributed as an standalone module
To compile
$ cd source/directory
$ make
Once built you can load and unload using the provided load.sh script;
load.sh will load the modules, load.sh u will unload them.
To install in the default kernel directories (and enable auto loading
when the device is plugged):
$ make install
$ depmod -a
If your kernel development files are located in a non standard
directory or if you want to build for a kernel that is not the
currently running one, set KDIR to the right location:
$ make KDIR=/path/to/kernel/dev/tree
For more information, please contact linux-wimax@intel.com.
3. Installing the firmware
The firmware can be obtained from http://linuxwimax.org or might have
been supplied with your hardware.
It has to be installed in the target system:
*
$ cp FIRMWAREFILE.sbcf /lib/firmware/i2400m-fw-BUSTYPE-1.3.sbcf
* NOTE: if your firmware came in an .rpm or .deb file, just install
it as normal, with the rpm (rpm -i FIRMWARE.rpm) or dpkg
(dpkg -i FIRMWARE.deb) commands. No further action is needed.
* BUSTYPE will be usb or sdio, depending on the hardware you have.
Each hardware type comes with its own firmware and will not work
with other types.
4. Design
This package contains two major parts: a WiMAX kernel stack and a
driver for the Intel i2400m.
The WiMAX stack is designed to provide for common WiMAX control
services to current and future WiMAX devices from any vendor; please
see README.wimax for details.
The i2400m kernel driver is broken up in two main parts: the bus
generic driver and the bus-specific drivers. The bus generic driver
forms the drivercore and contain no knowledge of the actual method we
use to connect to the device. The bus specific drivers are just the
glue to connect the bus-generic driver and the device. Currently only
USB and SDIO are supported. See drivers/net/wimax/i2400m/i2400m.h for
more information.
The bus generic driver is logically broken up in two parts: OS-glue and
hardware-glue. The OS-glue interfaces with Linux. The hardware-glue
interfaces with the device on using an interface provided by the
bus-specific driver. The reason for this breakup is to be able to
easily reuse the hardware-glue to write drivers for other OSes; note
the hardware glue part is written as a native Linux driver; no
abstraction layers are used, so to port to another OS, the Linux kernel
API calls should be replaced with the target OS's.
5. Usage
To load the driver, follow the instructions in the install section;
once the driver is loaded, plug in the device (unless it is permanently
plugged in). The driver will enumerate the device, upload the firmware
and output messages in the kernel log (dmesg, /var/log/messages or
/var/log/kern.log) such as:
...
i2400m_usb 5-4:1.0: firmware interface version 8.0.0
i2400m_usb 5-4:1.0: WiMAX interface wmx0 (00:1d:e1:01:94:2c) ready
At this point the device is ready to work.
Current versions require the Intel WiMAX Network Service in userspace
to make things work. See the network service's README for instructions
on how to scan, connect and disconnect.
5.1. Module parameters
Module parameters can be set at kernel or module load time or by
echoing values:
$ echo VALUE > /sys/module/MODULENAME/parameters/PARAMETERNAME
To make changes permanent, for example, for the i2400m module, you can
also create a file named /etc/modprobe.d/i2400m containing:
options i2400m idle_mode_disabled=1
To find which parameters are supported by a module, run:
$ modinfo path/to/module.ko
During kernel bootup (if the driver is linked in the kernel), specify
the following to the kernel command line:
i2400m.PARAMETER=VALUE
5.1.1. i2400m: idle_mode_disabled
The i2400m module supports a parameter to disable idle mode. This
parameter, once set, will take effect only when the device is
reinitialized by the driver (eg: following a reset or a reconnect).
5.2. Debug operations: debugfs entries
The driver will register debugfs entries that allow the user to tweak
debug settings. There are three main container directories where
entries are placed, which correspond to the three blocks a i2400m WiMAX
driver has:
* /sys/kernel/debug/wimax:DEVNAME/ for the generic WiMAX stack
controls
* /sys/kernel/debug/wimax:DEVNAME/i2400m for the i2400m generic
driver controls
* /sys/kernel/debug/wimax:DEVNAME/i2400m-usb (or -sdio) for the
bus-specific i2400m-usb or i2400m-sdio controls).
Of course, if debugfs is mounted in a directory other than
/sys/kernel/debug, those paths will change.
5.2.1. Increasing debug output
The files named *dl_* indicate knobs for controlling the debug output
of different submodules:
*
# find /sys/kernel/debug/wimax\:wmx0 -name \*dl_\*
/sys/kernel/debug/wimax:wmx0/i2400m-usb/dl_tx
/sys/kernel/debug/wimax:wmx0/i2400m-usb/dl_rx
/sys/kernel/debug/wimax:wmx0/i2400m-usb/dl_notif
/sys/kernel/debug/wimax:wmx0/i2400m-usb/dl_fw
/sys/kernel/debug/wimax:wmx0/i2400m-usb/dl_usb
/sys/kernel/debug/wimax:wmx0/i2400m/dl_tx
/sys/kernel/debug/wimax:wmx0/i2400m/dl_rx
/sys/kernel/debug/wimax:wmx0/i2400m/dl_rfkill
/sys/kernel/debug/wimax:wmx0/i2400m/dl_netdev
/sys/kernel/debug/wimax:wmx0/i2400m/dl_fw
/sys/kernel/debug/wimax:wmx0/i2400m/dl_debugfs
/sys/kernel/debug/wimax:wmx0/i2400m/dl_driver
/sys/kernel/debug/wimax:wmx0/i2400m/dl_control
/sys/kernel/debug/wimax:wmx0/wimax_dl_stack
/sys/kernel/debug/wimax:wmx0/wimax_dl_op_rfkill
/sys/kernel/debug/wimax:wmx0/wimax_dl_op_reset
/sys/kernel/debug/wimax:wmx0/wimax_dl_op_msg
/sys/kernel/debug/wimax:wmx0/wimax_dl_id_table
/sys/kernel/debug/wimax:wmx0/wimax_dl_debugfs
By reading the file you can obtain the current value of said debug
level; by writing to it, you can set it.
To increase the debug level of, for example, the i2400m's generic TX
engine, just write:
$ echo 3 > /sys/kernel/debug/wimax:wmx0/i2400m/dl_tx
Increasing numbers yield increasing debug information; for details of
what is printed and the available levels, check the source. The code
uses 0 for disabled and increasing values until 8.
5.2.2. RX and TX statistics
The i2400m/rx_stats and i2400m/tx_stats provide statistics about the
data reception/delivery from the device:
$ cat /sys/kernel/debug/wimax:wmx0/i2400m/rx_stats
45 1 3 34 3104 48 480
The numbers reported are
* packets/RX-buffer: total, min, max
* RX-buffers: total RX buffers received, accumulated RX buffer size
in bytes, min size received, max size received
Thus, to find the average buffer size received, divide accumulated
RX-buffer / total RX-buffers.
To clear the statistics back to 0, write anything to the rx_stats file:
$ echo 1 > /sys/kernel/debug/wimax:wmx0/i2400m_rx_stats
Likewise for TX.
Note the packets this debug file refers to are not network packet, but
packets in the sense of the device-specific protocol for communication
to the host. See drivers/net/wimax/i2400m/tx.c.
5.2.3. Tracing messages received from user space
To echo messages received from user space into the trace pipe that the
i2400m driver creates, set the debug file i2400m/trace_msg_from_user to
1:
*
$ echo 1 > /sys/kernel/debug/wimax:wmx0/i2400m/trace_msg_from_user
5.2.4. Performing a device reset
By writing a 0, a 1 or a 2 to the file
/sys/kernel/debug/wimax:wmx0/reset, the driver performs a warm (without
disconnecting from the bus), cold (disconnecting from the bus) or bus
(bus specific) reset on the device.
5.2.5. Asking the device to enter power saving mode
By writing any value to the /sys/kernel/debug/wimax:wmx0 file, the
device will attempt to enter power saving mode.
6. Troubleshooting
6.1. Driver complains about 'i2400m-fw-usb-1.2.sbcf: request failed'
If upon connecting the device, the following is output in the kernel
log:
i2400m_usb 5-4:1.0: fw i2400m-fw-usb-1.3.sbcf: request failed: -2
This means that the driver cannot locate the firmware file named
/lib/firmware/i2400m-fw-usb-1.2.sbcf. Check that the file is present in
the right location.

81
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@ -0,0 +1,81 @@
Linux kernel WiMAX stack
(C) 2008 Intel Corporation < linux-wimax@intel.com >
This provides a basic Linux kernel WiMAX stack to provide a common
control API for WiMAX devices, usable from kernel and user space.
1. Design
The WiMAX stack is designed to provide for common WiMAX control
services to current and future WiMAX devices from any vendor.
Because currently there is only one and we don't know what would be the
common services, the APIs it currently provides are very minimal.
However, it is done in such a way that it is easily extensible to
accommodate future requirements.
The stack works by embedding a struct wimax_dev in your device's
control structures. This provides a set of callbacks that the WiMAX
stack will call in order to implement control operations requested by
the user. As well, the stack provides API functions that the driver
calls to notify about changes of state in the device.
The stack exports the API calls needed to control the device to user
space using generic netlink as a marshalling mechanism. You can access
them using your own code or use the wrappers provided for your
convenience in libwimax (in the wimax-tools package).
For detailed information on the stack, please see
include/linux/wimax.h.
2. Usage
For usage in a driver (registration, API, etc) please refer to the
instructions in the header file include/linux/wimax.h.
When a device is registered with the WiMAX stack, a set of debugfs
files will appear in /sys/kernel/debug/wimax:wmxX can tweak for
control.
2.1. Obtaining debug information: debugfs entries
The WiMAX stack is compiled, by default, with debug messages that can
be used to diagnose issues. By default, said messages are disabled.
The drivers will register debugfs entries that allow the user to tweak
debug settings.
Each driver, when registering with the stack, will cause a debugfs
directory named wimax:DEVICENAME to be created; optionally, it might
create more subentries below it.
2.1.1. Increasing debug output
The files named *dl_* indicate knobs for controlling the debug output
of different submodules of the WiMAX stack:
*
# find /sys/kernel/debug/wimax\:wmx0 -name \*dl_\*
/sys/kernel/debug/wimax:wmx0/wimax_dl_stack
/sys/kernel/debug/wimax:wmx0/wimax_dl_op_rfkill
/sys/kernel/debug/wimax:wmx0/wimax_dl_op_reset
/sys/kernel/debug/wimax:wmx0/wimax_dl_op_msg
/sys/kernel/debug/wimax:wmx0/wimax_dl_id_table
/sys/kernel/debug/wimax:wmx0/wimax_dl_debugfs
/sys/kernel/debug/wimax:wmx0/.... # other driver specific files
NOTE: Of course, if debugfs is mounted in a directory other than
/sys/kernel/debug, those paths will change.
By reading the file you can obtain the current value of said debug
level; by writing to it, you can set it.
To increase the debug level of, for example, the id-table submodule,
just write:
$ echo 3 > /sys/kernel/debug/wimax:wmx0/wimax_dl_id_table
Increasing numbers yield increasing debug information; for details of
what is printed and the available levels, check the source. The code
uses 0 for disabled and increasing values until 8.

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