diff options
Diffstat (limited to 'Documentation')
64 files changed, 3226 insertions, 763 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-regulator b/Documentation/ABI/testing/sysfs-class-regulator index 3731f6f29bcb..873ef1fc1569 100644 --- a/Documentation/ABI/testing/sysfs-class-regulator +++ b/Documentation/ABI/testing/sysfs-class-regulator @@ -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. - - This will be one of the following strings: + when suspended to memory, for regulators implementing suspend + configuration constraints. - '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. - - This will be one of the following strings: + when suspended to disk, for regulators implementing + suspend configuration constraints. - '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. - - This will be one of the following strings: + state when suspended to standby, for regulators implementing + suspend configuration constraints. - 'enabled' - 'disabled' - 'not defined' + This will be one of the same strings reported by + the "state" attribute. diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt index b462bb149543..52441694fe03 100644 --- a/Documentation/DMA-API.txt +++ b/Documentation/DMA-API.txt @@ -170,16 +170,15 @@ Returns: 0 if successful and a negative error if not. u64 dma_get_required_mask(struct device *dev) -After setting the mask with dma_set_mask(), this API returns the -actual mask (within that already set) that the platform actually -requires to operate efficiently. Usually this means the returned mask +This API returns the mask that the platform requires to +operate efficiently. Usually this means the returned mask is the minimum required to cover all of memory. Examining the required mask gives drivers with variable descriptor sizes the opportunity to use smaller descriptors as necessary. Requesting the required mask does not alter the current mask. If you -wish to take advantage of it, you should issue another dma_set_mask() -call to lower the mask again. +wish to take advantage of it, you should issue a dma_set_mask() +call to set the mask to the value returned. Part Id - Streaming DMA mappings diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile index 0a08126d3094..dc3154e49279 100644 --- a/Documentation/DocBook/Makefile +++ b/Documentation/DocBook/Makefile @@ -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): diff --git a/Documentation/DocBook/networking.tmpl b/Documentation/DocBook/networking.tmpl index 627707a3cb9d..59ad69a9d777 100644 --- a/Documentation/DocBook/networking.tmpl +++ b/Documentation/DocBook/networking.tmpl @@ -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"> diff --git a/Documentation/DocBook/regulator.tmpl b/Documentation/DocBook/regulator.tmpl new file mode 100644 index 000000000000..53f4f8d3b810 --- /dev/null +++ b/Documentation/DocBook/regulator.tmpl @@ -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> diff --git a/Documentation/PCI/pci.txt b/Documentation/PCI/pci.txt index fd4907a2968c..7f6de6ea5b47 100644 --- a/Documentation/PCI/pci.txt +++ b/Documentation/PCI/pci.txt @@ -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 diff --git a/Documentation/RCU/00-INDEX b/Documentation/RCU/00-INDEX index 7dc0695a8f90..9bb62f7b89c3 100644 --- a/Documentation/RCU/00-INDEX +++ b/Documentation/RCU/00-INDEX @@ -12,6 +12,8 @@ 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 diff --git a/Documentation/RCU/rcubarrier.txt b/Documentation/RCU/rcubarrier.txt new file mode 100644 index 000000000000..909602d409bb --- /dev/null +++ b/Documentation/RCU/rcubarrier.txt @@ -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! diff --git a/Documentation/accounting/getdelays.c b/Documentation/accounting/getdelays.c index cc49400b4af8..7ea231172c85 100644 --- a/Documentation/accounting/getdelays.c +++ b/Documentation/accounting/getdelays.c @@ -392,6 +392,10 @@ int main(int argc, char *argv[]) goto err; } } + if (!maskset && !tid && !containerset) { + usage(); + goto err; + } do { int i; diff --git a/Documentation/bad_memory.txt b/Documentation/bad_memory.txt new file mode 100644 index 000000000000..df8416213202 --- /dev/null +++ b/Documentation/bad_memory.txt @@ -0,0 +1,45 @@ +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 + diff --git a/Documentation/blackfin/00-INDEX b/Documentation/blackfin/00-INDEX index 7cb3b356b249..d6840a91e1e1 100644 --- a/Documentation/blackfin/00-INDEX +++ b/Documentation/blackfin/00-INDEX @@ -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. diff --git a/Documentation/blackfin/bfin-gpio-notes.txt b/Documentation/blackfin/bfin-gpio-notes.txt new file mode 100644 index 000000000000..9898c7ded7d3 --- /dev/null +++ b/Documentation/blackfin/bfin-gpio-notes.txt @@ -0,0 +1,71 @@ +/* + * 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. + + + diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt index d9014aa0eb68..d9e5d6f41b92 100644 --- a/Documentation/cgroups/cgroups.txt +++ b/Documentation/cgroups/cgroups.txt @@ -1,7 +1,8 @@ CGROUPS ------- -Written by Paul Menage <menage@google.com> based on Documentation/cpusets.txt +Written by Paul Menage <menage@google.com> based on +Documentation/cgroups/cpusets.txt Original copyright statements from cpusets.txt: Portions Copyright (C) 2004 BULL SA. @@ -68,7 +69,7 @@ On their own, the only use for cgroups is for simple job tracking. The intention is that other subsystems hook into the generic cgroup support to provide new attributes for cgroups, such as accounting/limiting the resources which processes in a cgroup can -access. For example, cpusets (see Documentation/cpusets.txt) allows +access. For example, cpusets (see Documentation/cgroups/cpusets.txt) allows you to associate a set of CPUs and a set of memory nodes with the tasks in each cgroup. @@ -227,7 +228,6 @@ 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 +360,7 @@ 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 +479,6 @@ 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 +497,7 @@ 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 +511,7 @@ 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 +521,7 @@ 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 +529,7 @@ 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 diff --git a/Documentation/controllers/cpuacct.txt b/Documentation/cgroups/cpuacct.txt index bb775fbe43d7..bb775fbe43d7 100644 --- a/Documentation/controllers/cpuacct.txt +++ b/Documentation/cgroups/cpuacct.txt diff --git a/Documentation/cpusets.txt b/Documentation/cgroups/cpusets.txt index 5c86c258c791..5c86c258c791 100644 --- a/Documentation/cpusets.txt +++ b/Documentation/cgroups/cpusets.txt diff --git a/Documentation/controllers/devices.txt b/Documentation/cgroups/devices.txt index 7cc6e6a60672..7cc6e6a60672 100644 --- a/Documentation/controllers/devices.txt +++ b/Documentation/cgroups/devices.txt diff --git a/Documentation/cgroups/memcg_test.txt b/Documentation/cgroups/memcg_test.txt new file mode 100644 index 000000000000..19533f93b7a2 --- /dev/null +++ b/Documentation/cgroups/memcg_test.txt @@ -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/cgroups/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. diff --git a/Documentation/controllers/memory.txt b/Documentation/cgroups/memory.txt index 1c07547d3f81..e1501964df1e 100644 --- a/Documentation/controllers/memory.txt +++ b/Documentation/cgroups/memory.txt @@ -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. + +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. -5. TODO +7. TODO 1. Add support for accounting huge pages (as a separate controller) 2. Make per-cgroup scanner reclaim not-shared pages first diff --git a/Documentation/controllers/resource_counter.txt b/Documentation/cgroups/resource_counter.txt index f196ac1d7d25..f196ac1d7d25 100644 --- a/Documentation/controllers/resource_counter.txt +++ b/Documentation/cgroups/resource_counter.txt diff --git a/Documentation/crypto/async-tx-api.txt b/Documentation/crypto/async-tx-api.txt index c1e9545c59bd..9f59fcbf5d82 100644 --- a/Documentation/crypto/async-tx-api.txt +++ b/Documentation/crypto/async-tx-api.txt @@ -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. - -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) - -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. - -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. - -Below is the example of how to extend this functionality for -platform-specific filtering of the available channels beyond the -standard capability mask: - -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; - - . . . -} +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 interface is: +struct dma_chan *dma_request_channel(dma_cap_mask_t mask, + dma_filter_fn filter_fn, + void *filter_param); + +Where dma_filter_fn is defined as: +typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param); + +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. + +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. + +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 diff --git a/Documentation/dell_rbu.txt b/Documentation/dell_rbu.txt index 2c0d631de0cf..c11b931f8f98 100644 --- a/Documentation/dell_rbu.txt +++ b/Documentation/dell_rbu.txt @@ -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. diff --git a/Documentation/development-process/4.Coding b/Documentation/development-process/4.Coding index 014aca8f14e2..a5a3450faaa0 100644 --- a/Documentation/development-process/4.Coding +++ b/Documentation/development-process/4.Coding @@ -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. diff --git a/Documentation/dmaengine.txt b/Documentation/dmaengine.txt new file mode 100644 index 000000000000..0c1c2f63c0a9 --- /dev/null +++ b/Documentation/dmaengine.txt @@ -0,0 +1 @@ +See Documentation/crypto/async-tx-api.txt diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 2193be53e773..5ddbe350487a 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -318,6 +318,14 @@ 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" diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index cfbfa15a46ba..ec6a9392a173 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -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 diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt new file mode 100644 index 000000000000..64087c34327f --- /dev/null +++ b/Documentation/filesystems/btrfs.txt @@ -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 diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index 174eaff7ded9..cec829bc7291 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -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: diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 32e94635484f..bbebc3a43ac0 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -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 .............................................................................. @@ -1370,292 +1371,8 @@ auto_msgmni default value is 1. 2.4 /proc/sys/vm - The virtual memory subsystem ----------------------------------------------- -The files in this directory can be used to tune the operation of the virtual -memory (VM) subsystem of the Linux kernel. - -vfs_cache_pressure ------------------- - -Controls the tendency of the kernel to reclaim the memory which is used for -caching of directory and inode objects. - -At the default value of vfs_cache_pressure=100 the kernel will attempt to -reclaim dentries and inodes at a "fair" rate with respect to pagecache and -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 ----------------------- - -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 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 -------------------------- - -The pdflush writeback daemons will periodically wake up and write `old' data -out to disk. This tunable expresses the interval between those wakeups, in -100'ths of a second. - -Setting this to zero disables periodic writeback altogether. - -dirty_expire_centisecs ----------------------- - -This tunable is used to define when dirty data is old enough to be eligible -for writeout by the pdflush daemons. It is expressed in 100'ths of a second. -Data which has been dirty in-memory for longer than this interval will be -written out next time a pdflush daemon wakes up. - -highmem_is_dirtyable --------------------- - -Only present if CONFIG_HIGHMEM is set. - -This defaults to 0 (false), meaning that the ratios set above are calculated -as a percentage of lowmem only. This protects against excessive scanning -in page reclaim, swapping and general VM distress. - -Setting this to 1 can be useful on 32 bit machines where you want to make -random changes within an MMAPed file that is larger than your available -lowmem without causing large quantities of random IO. Is is safe if the -behavior of all programs running on the machine is known and memory will -not be otherwise stressed. - -legacy_va_layout ----------------- - -If non-zero, this sysctl disables the new 32-bit mmap mmap layout - the kernel -will use the legacy (2.4) layout for all processes. - -lowmem_reserve_ratio ---------------------- - -For some specialised workloads on highmem machines it is dangerous for -the kernel to allow process memory to be allocated from the "lowmem" -zone. This is because that memory could then be pinned via the mlock() -system call, or by unavailability of swapspace. - -And on large highmem machines this lack of reclaimable lowmem memory -can be fatal. - -So the Linux page allocator has a mechanism which prevents allocations -which _could_ use highmem from using too much lowmem. This means that -a certain amount of lowmem is defended from the possibility of being -captured into pinned user memory. - -(The same argument applies to the old 16 megabyte ISA DMA region. This -mechanism will also defend that region from allocations which could use -highmem or lowmem). - -The `lowmem_reserve_ratio' tunable determines how aggressive the kernel is -in defending these lower zones. - -If you have a machine which uses highmem or ISA DMA and your -applications are using mlock(), or if you are running with no swap then -you probably should change the lowmem_reserve_ratio setting. - -The lowmem_reserve_ratio is an array. You can see them by reading this file. -- -% cat /proc/sys/vm/lowmem_reserve_ratio -256 256 32 -- -Note: # of this elements is one fewer than number of zones. Because the highest - zone's value is not necessary for following calculation. - -But, these values are not used directly. The kernel calculates # of protection -pages for each zones from them. These are shown as array of protection pages -in /proc/zoneinfo like followings. (This is an example of x86-64 box). -Each zone has an array of protection pages like this. - -- -Node 0, zone DMA - pages free 1355 - min 3 - low 3 - high 4 - : - : - numa_other 0 - protection: (0, 2004, 2004, 2004) - ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - pagesets - cpu: 0 pcp: 0 - : -- -These protections are added to score to judge whether this zone should be used -for page allocation or should be reclaimed. - -In this example, if normal pages (index=2) are required to this DMA zone and -pages_high is used for watermark, the kernel judges this zone should not be -used because pages_free(1355) is smaller than watermark + protection[2] -(4 + 2004 = 2008). If this protection value is 0, this zone would be used for -normal page requirement. If requirement is DMA zone(index=0), protection[0] -(=0) is used. - -zone[i]'s protection[j] is calculated by following expression. - -(i < j): - zone[i]->protection[j] - = (total sums of present_pages from zone[i+1] to zone[j] on the node) - / lowmem_reserve_ratio[i]; -(i = j): - (should not be protected. = 0; -(i > j): - (not necessary, but looks 0) - -The default values of lowmem_reserve_ratio[i] are - 256 (if zone[i] means DMA or DMA32 zone) - 32 (others). -As above expression, they are reciprocal number of ratio. -256 means 1/256. # of protection pages becomes about "0.39%" of total present -pages of higher zones on the node. - -If you would like to protect more pages, smaller values are effective. -The minimum value is 1 (1/1 -> 100%). - -page-cluster ------------- - -page-cluster controls the number of pages which are written to swap in -a single attempt. The swap I/O size. - -It is a logarithmic value - setting it to zero means "1 page", setting -it to 1 means "2 pages", setting it to 2 means "4 pages", etc. - -The default value is three (eight pages at a time). There may be some -small benefits in tuning this to a different value if your workload is -swap-intensive. - -overcommit_memory ------------------ - -Controls overcommit of system memory, possibly allowing processes -to allocate (but not use) more memory than is actually available. - - -0 - Heuristic overcommit handling. Obvious overcommits of - address space are refused. Used for a typical system. It - ensures a seriously wild allocation fails while allowing - overcommit to reduce swap usage. root is allowed to - allocate slightly more memory in this mode. This is the - default. - -1 - Always overcommit. Appropriate for some scientific - applications. - -2 - Don't overcommit. The total address space commit - for the system is not permitted to exceed swap plus a - configurable percentage (default is 50) of physical RAM. - Depending on the percentage you use, in most situations - this means a process will not be killed while attempting - to use already-allocated memory but will receive errors - on memory allocation as appropriate. - -overcommit_ratio ----------------- - -Percentage of physical memory size to include in overcommit calculations -(see above.) - -Memory allocation limit = swapspace + physmem * (overcommit_ratio / 100) - - swapspace = total size of all swap areas - physmem = size of physical memory in system - -nr_hugepages and hugetlb_shm_group ----------------------------------- - -nr_hugepages configures number of hugetlb page reserved for the system. - -hugetlb_shm_group contains group id that is allowed to create SysV shared -memory segment using hugetlb page. - -hugepages_treat_as_movable --------------------------- - -This parameter is only useful when kernelcore= is specified at boot time to -create ZONE_MOVABLE for pages that may be reclaimed or migrated. Huge pages -are not movable so are not normally allocated from ZONE_MOVABLE. A non-zero -value written to hugepages_treat_as_movable allows huge pages to be allocated -from ZONE_MOVABLE. - -Once enabled, the ZONE_MOVABLE is treated as an area of memory the huge -pages pool can easily grow or shrink within. Assuming that applications are -not running that mlock() a lot of memory, it is likely the huge pages pool -can grow to the size of ZONE_MOVABLE by repeatedly entering the desired value -into nr_hugepages and triggering page reclaim. - -laptop_mode ------------ - -laptop_mode is a knob that controls "laptop mode". All the things that are -controlled by this knob are discussed in Documentation/laptops/laptop-mode.txt. - -block_dump ----------- - -block_dump enables block I/O debugging when set to a nonzero value. More -information on block I/O debugging is in Documentation/laptops/laptop-mode.txt. - -swap_token_timeout ------------------- - -This file contains valid hold time of swap out protection token. The Linux -VM has token based thrashing control mechanism and uses the token to prevent -unnecessary page faults in thrashing situation. The unit of the value is -second. The value would be useful to tune thrashing behavior. - -drop_caches ------------ - -Writing to this will cause the kernel to drop clean caches, dentries and -inodes from memory, causing that memory to become free. - -To free pagecache: - echo 1 > /proc/sys/vm/drop_caches -To free dentries and inodes: - echo 2 > /proc/sys/vm/drop_caches -To free pagecache, dentries and inodes: - echo 3 > /proc/sys/vm/drop_caches - -As this is a non-destructive operation and dirty objects are not freeable, the -user should run `sync' first. +Please see: Documentation/sysctls/vm.txt for a description of these +entries. 2.5 /proc/sys/dev - Device specific parameters diff --git a/Documentation/filesystems/squashfs.txt b/Documentation/filesystems/squashfs.txt new file mode 100644 index 000000000000..3e79e4a7a392 --- /dev/null +++ b/Documentation/filesystems/squashfs.txt @@ -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. diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index ef19afa186a9..deeeed0faa8f 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -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 diff --git a/Documentation/hwmon/abituguru-datasheet b/Documentation/hwmon/abituguru-datasheet index aef5a9b36846..d9251efdcec7 100644 --- a/Documentation/hwmon/abituguru-datasheet +++ b/Documentation/hwmon/abituguru-datasheet @@ -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) diff --git a/Documentation/hwmon/adt7475 b/Documentation/hwmon/adt7475 new file mode 100644 index 000000000000..a2b1abec850e --- /dev/null +++ b/Documentation/hwmon/adt7475 @@ -0,0 +1,87 @@ +This describes the interface for the ADT7475 driver: + +(there are 4 fans, numbered fan1 to fan4): + +fanX_input Read the current speed of the fan (in RPMs) +fanX_min Read/write the minimum speed of the fan. Dropping + below this sets an alarm. + +(there are three PWMs, numbered pwm1 to pwm3): + +pwmX Read/write the current duty cycle of the PWM. Writes + only have effect when auto mode is turned off (see + below). Range is 0 - 255. + +pwmX_enable Fan speed control method: + + 0 - No control (fan at full speed) + 1 - Manual fan speed control (using pwm[1-*]) + 2 - Automatic fan speed control + +pwmX_auto_channels_temp Select which channels affect this PWM + + 1 - TEMP1 controls PWM + 2 - TEMP2 controls PWM + 4 - TEMP3 controls PWM + 6 - TEMP2 and TEMP3 control PWM + 7 - All three inputs control PWM + +pwmX_freq Read/write the PWM frequency in Hz. The number + should be one of the following: + + 11 Hz + 14 Hz + 22 Hz + 29 Hz + 35 Hz + 44 Hz + 58 Hz + 88 Hz + +pwmX_auto_point1_pwm Read/write the minimum PWM duty cycle in automatic mode + +pwmX_auto_point2_pwm Read/write the maximum PWM duty cycle in automatic mode + +(there are three temperature settings numbered temp1 to temp3): + +tempX_input Read the current temperature. The value is in milli + degrees of Celsius. + +tempX_max Read/write the upper temperature limit - exceeding this + will cause an alarm. + +tempX_min Read/write the lower temperature limit - exceeding this + will cause an alarm. + +tempX_offset Read/write the temperature adjustment offset + +tempX_crit Read/write the THERM limit for remote1. + +tempX_crit_hyst Set the temperature value below crit where the + fans will stay on - this helps drive the temperature + low enough so it doesn't stay near the edge and + cause THERM to keep tripping. + +tempX_auto_point1_temp Read/write the minimum temperature where the fans will + turn on in automatic mode. + +tempX_auto_point2_temp Read/write the maximum temperature over which the fans + will run in automatic mode. tempX_auto_point1_temp + and tempX_auto_point2_temp together define the + range of automatic control. + +tempX_alarm Read a 1 if the max/min alarm is set +tempX_fault Read a 1 if either temp1 or temp3 diode has a fault + +(There are two voltage settings, in1 and in2): + +inX_input Read the current voltage on VCC. Value is in + millivolts. + +inX_min read/write the minimum voltage limit. + Dropping below this causes an alarm. + +inX_max read/write the maximum voltage limit. + Exceeding this causes an alarm. + +inX_alarm Read a 1 if the max/min alarm is set. diff --git a/Documentation/hwmon/f71882fg b/Documentation/hwmon/f71882fg new file mode 100644 index 000000000000..a8321267b5b6 --- /dev/null +++ b/Documentation/hwmon/f71882fg @@ -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. diff --git a/Documentation/hwmon/it87 b/Documentation/hwmon/it87 index 042c0415140b..659315d98e00 100644 --- a/Documentation/hwmon/it87 +++ b/Documentation/hwmon/it87 @@ -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. diff --git a/Documentation/hwmon/lis3lv02d b/Documentation/hwmon/lis3lv02d index 65dfb0c0fd67..0fcfc4a7ccdc 100644 --- a/Documentation/hwmon/lis3lv02d +++ b/Documentation/hwmon/lis3lv02d @@ -13,18 +13,21 @@ Author: Description ----------- -This driver provides support for the accelerometer found in various HP laptops -sporting the feature officially called "HP Mobile Data Protection System 3D" or -"HP 3D DriveGuard". It detect automatically laptops with this sensor. Known models -(for now the HP 2133, nc6420, nc2510, nc8510, nc84x0, nw9440 and nx9420) will -have their axis automatically oriented on standard way (eg: you can directly -play neverball). The accelerometer data is readable via +This driver provides support for the accelerometer found in various HP +laptops sporting the feature officially called "HP Mobile Data +Protection System 3D" or "HP 3D DriveGuard". It detect automatically +laptops with this sensor. Known models (for now the HP 2133, nc6420, +nc2510, nc8510, nc84x0, nw9440 and nx9420) will have their axis +automatically oriented on standard way (eg: you can directly play +neverball). The accelerometer data is readable via /sys/devices/platform/lis3lv02d. Sysfs attributes under /sys/devices/platform/lis3lv02d/: position - 3D position that the accelerometer reports. Format: "(x,y,z)" -calibrate - read: values (x, y, z) that are used as the base for input class device operation. - write: forces the base to be recalibrated with the current position. +calibrate - read: values (x, y, z) that are used as the base for input + class device operation. + write: forces the base to be recalibrated with the current + position. rate - reports the sampling rate of the accelerometer device in HZ This driver also provides an absolute input class device, allowing @@ -39,11 +42,12 @@ the accelerometer are converted into a "standard" organisation of the axes * When the laptop is horizontal the position reported is about 0 for X and Y and a positive value for Z * If the left side is elevated, X increases (becomes positive) - * If the front side (where the touchpad is) is elevated, Y decreases (becomes negative) + * If the front side (where the touchpad is) is elevated, Y decreases + (becomes negative) * If the laptop is put upside-down, Z becomes negative -If your laptop model is not recognized (cf "dmesg"), you can send an email to the -authors to add it to the database. When reporting a new laptop, please include -the output of "dmidecode" plus the value of /sys/devices/platform/lis3lv02d/position -in these four cases. +If your laptop model is not recognized (cf "dmesg"), you can send an +email to the authors to add it to the database. When reporting a new +laptop, please include the output of "dmidecode" plus the value of +/sys/devices/platform/lis3lv02d/position in these four cases. diff --git a/Documentation/hwmon/lm70 b/Documentation/hwmon/lm70 index 2bdd3feebf53..0d240291e3cc 100644 --- a/Documentation/hwmon/lm70 +++ b/Documentation/hwmon/lm70 @@ -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 diff --git a/Documentation/hwmon/lm85 b/Documentation/hwmon/lm85 index 400620741290..a13680871bc7 100644 --- a/Documentation/hwmon/lm85 +++ b/Documentation/hwmon/lm85 @@ -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 diff --git a/Documentation/hwmon/ltc4245 b/Documentation/hwmon/ltc4245 new file mode 100644 index 000000000000..bae7a3adc5d8 --- /dev/null +++ b/Documentation/hwmon/ltc4245 @@ -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) diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index 51771847e816..923f9ddee8f6 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt @@ -124,3 +124,10 @@ 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 diff --git a/Documentation/kbuild/modules.txt b/Documentation/kbuild/modules.txt index 1821c077b435..b1096da953c8 100644 --- a/Documentation/kbuild/modules.txt +++ b/Documentation/kbuild/modules.txt @@ -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 diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 0b3f6711d2f1..8511d3532c27 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -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 @@ -828,8 +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 @@ -877,17 +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. @@ -918,6 +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 @@ -1069,8 +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 @@ -1557,6 +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 @@ -2295,7 +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 @@ -2383,6 +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. diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index 71f0fe1fc1b0..41bc99fa1884 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -1,7 +1,7 @@ ThinkPad ACPI Extras Driver - Version 0.21 - May 29th, 2008 + Version 0.22 + November 23rd, 2008 Borislav Deianov <borislav@users.sf.net> Henrique de Moraes Holschuh <hmh@hmh.eng.br> @@ -16,7 +16,8 @@ supported by the generic Linux ACPI drivers. This driver used to be named ibm-acpi until kernel 2.6.21 and release 0.13-20070314. It used to be in the drivers/acpi tree, but it was moved to the drivers/misc tree and renamed to thinkpad-acpi for kernel -2.6.22, and release 0.14. +2.6.22, and release 0.14. It was moved to drivers/platform/x86 for +kernel 2.6.29 and release 0.22. The driver is named "thinkpad-acpi". In some places, like module names, "thinkpad_acpi" is used because of userspace issues. @@ -1412,6 +1413,24 @@ Sysfs notes: rfkill controller switch "tpacpi_wwan_sw": refer to Documentation/rfkill.txt for details. +EXPERIMENTAL: UWB +----------------- + +This feature is marked EXPERIMENTAL because it has not been extensively +tested and validated in various ThinkPad models yet. The feature may not +work as expected. USE WITH CAUTION! To use this feature, you need to supply +the experimental=1 parameter when loading the module. + +sysfs rfkill class: switch "tpacpi_uwb_sw" + +This feature exports an rfkill controller for the UWB device, if one is +present and enabled in the BIOS. + +Sysfs notes: + + rfkill controller switch "tpacpi_uwb_sw": refer to + Documentation/rfkill.txt for details. + Multiple Commands, Module Parameters ------------------------------------ @@ -1475,7 +1494,7 @@ 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 diff --git a/Documentation/mips/AU1xxx_IDE.README b/Documentation/mips/AU1xxx_IDE.README index f54962aea84d..8ace35ebdcd5 100644 --- a/Documentation/mips/AU1xxx_IDE.README +++ b/Documentation/mips/AU1xxx_IDE.README @@ -52,14 +52,12 @@ Two files are introduced: b) 'drivers/ide/mips/au1xxx-ide.c' contains the functionality of the AU1XXX IDE driver -Four configs variables are introduced: +Following extra configs variables are introduced: CONFIG_BLK_DEV_IDE_AU1XXX_PIO_DBDMA - enable the PIO+DBDMA mode CONFIG_BLK_DEV_IDE_AU1XXX_MDMA2_DBDMA - enable the MWDMA mode CONFIG_BLK_DEV_IDE_AU1XXX_BURSTABLE_ON - set Burstable FIFO in DBDMA controller - CONFIG_BLK_DEV_IDE_AU1XXX_SEQTS_PER_RQ - maximum transfer size - per descriptor SUPPORTED IDE MODES @@ -87,7 +85,6 @@ CONFIG_BLK_DEV_IDEDMA_PCI=y CONFIG_IDEDMA_PCI_AUTO=y CONFIG_BLK_DEV_IDE_AU1XXX=y CONFIG_BLK_DEV_IDE_AU1XXX_MDMA2_DBDMA=y -CONFIG_BLK_DEV_IDE_AU1XXX_SEQTS_PER_RQ=128 CONFIG_BLK_DEV_IDEDMA=y CONFIG_IDEDMA_AUTO=y @@ -105,7 +102,6 @@ CONFIG_BLK_DEV_IDEDMA_PCI=y CONFIG_IDEDMA_PCI_AUTO=y CONFIG_BLK_DEV_IDE_AU1XXX=y CONFIG_BLK_DEV_IDE_AU1XXX_MDMA2_DBDMA=y -CONFIG_BLK_DEV_IDE_AU1XXX_SEQTS_PER_RQ=128 CONFIG_BLK_DEV_IDEDMA=y CONFIG_IDEDMA_AUTO=y diff --git a/Documentation/networking/rxrpc.txt b/Documentation/networking/rxrpc.txt index c3669a3fb4af..60d05eb77c64 100644 --- a/Documentation/networking/rxrpc.txt +++ b/Documentation/networking/rxrpc.txt @@ -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. diff --git a/Documentation/networking/tuntap.txt b/Documentation/networking/tuntap.txt index 839cbb71388b..c0aab985bad9 100644 --- a/Documentation/networking/tuntap.txt +++ b/Documentation/networking/tuntap.txt @@ -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 ? diff --git a/Documentation/nommu-mmap.txt b/Documentation/nommu-mmap.txt index 7714f57caad5..b565e8279d13 100644 --- a/Documentation/nommu-mmap.txt +++ b/Documentation/nommu-mmap.txt @@ -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'. diff --git a/Documentation/powerpc/dts-bindings/4xx/ndfc.txt b/Documentation/powerpc/dts-bindings/4xx/ndfc.txt new file mode 100644 index 000000000000..869f0b5f16e8 --- /dev/null +++ b/Documentation/powerpc/dts-bindings/4xx/ndfc.txt @@ -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>; + }; + }; +}; + + diff --git a/Documentation/powerpc/dts-bindings/fsl/board.txt b/Documentation/powerpc/dts-bindings/fsl/board.txt index 81a917ef96e9..6c974d28eeb4 100644 --- a/Documentation/powerpc/dts-bindings/fsl/board.txt +++ b/Documentation/powerpc/dts-bindings/fsl/board.txt @@ -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; + }; + }; diff --git a/Documentation/scheduler/sched-design-CFS.txt b/Documentation/scheduler/sched-design-CFS.txt index 8398ca4ff4ed..6f33593e59e2 100644 --- a/Documentation/scheduler/sched-design-CFS.txt +++ b/Documentation/scheduler/sched-design-CFS.txt @@ -231,7 +231,7 @@ CPU bandwidth control purposes: This options needs CONFIG_CGROUPS to be defined, and lets the administrator create arbitrary groups of tasks, using the "cgroup" pseudo filesystem. See - Documentation/cgroups.txt for more information about this filesystem. + Documentation/cgroups/cgroups.txt for more information about this filesystem. Only one of these options to group tasks can be chosen and not both. diff --git a/Documentation/scsi/ChangeLog.lpfc b/Documentation/scsi/ChangeLog.lpfc index ae3f962a7cfc..ff19a52fe004 100644 --- a/Documentation/scsi/ChangeLog.lpfc +++ b/Documentation/scsi/ChangeLog.lpfc @@ -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. diff --git a/Documentation/scsi/ChangeLog.ncr53c8xx b/Documentation/scsi/ChangeLog.ncr53c8xx index a9f721aeb11c..8b278c10edfd 100644 --- a/Documentation/scsi/ChangeLog.ncr53c8xx +++ b/Documentation/scsi/ChangeLog.ncr53c8xx @@ -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) diff --git a/Documentation/scsi/ChangeLog.sym53c8xx b/Documentation/scsi/ChangeLog.sym53c8xx index ef985ec348e6..02ffbc1e8a84 100644 --- a/Documentation/scsi/ChangeLog.sym53c8xx +++ b/Documentation/scsi/ChangeLog.sym53c8xx @@ -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. diff --git a/Documentation/scsi/scsi_fc_transport.txt b/Documentation/scsi/scsi_fc_transport.txt index 38d324d62b25..e5b071d46619 100644 --- a/Documentation/scsi/scsi_fc_transport.txt +++ b/Documentation/scsi/scsi_fc_transport.txt @@ -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 diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index 4b7ac21ea9eb..64eb1100eec1 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -275,7 +275,8 @@ STAC9200 dell-m25 Dell Inspiron E1505n dell-m26 Dell Inspiron 1501 dell-m27 Dell Inspiron E1705/9400 - gateway Gateway laptops with EAPD control + gateway-m4 Gateway laptops with EAPD control + gateway-m4-2 Gateway laptops with EAPD control panasonic Panasonic CF-74 STAC9205/9254 @@ -302,6 +303,7 @@ STAC9220/9221 macbook-pro Intel Mac Book Pro 2nd generation (eq. type 3) imac-intel Intel iMac (eq. type 2) imac-intel-20 Intel iMac (newer version) (eq. type 3) + ecs202 ECS/PC chips dell-d81 Dell (unknown) dell-d82 Dell (unknown) dell-m81 Dell (unknown) @@ -310,9 +312,13 @@ STAC9220/9221 STAC9202/9250/9251 ================== ref Reference board, base config + m1 Some Gateway MX series laptops (NX560XL) + m1-2 Some Gateway MX series laptops (MX6453) + m2 Some Gateway MX series laptops (M255) m2-2 Some Gateway MX series laptops + m3 Some Gateway MX series laptops + m5 Some Gateway MX series laptops (MP6954) m6 Some Gateway NX series laptops - pa6 Gateway NX860 series STAC9227/9228/9229/927x ======================= @@ -329,6 +335,7 @@ STAC92HD71B* dell-m4-1 Dell desktops dell-m4-2 Dell desktops dell-m4-3 Dell desktops + hp-m4 HP dv laptops STAC92HD73* =========== @@ -337,6 +344,7 @@ STAC92HD73* dell-m6-amic Dell desktops/laptops with analog mics dell-m6-dmic Dell desktops/laptops with digital mics dell-m6 Dell desktops/laptops with both type of mics + dell-eq Dell desktops/laptops STAC92HD83* =========== diff --git a/Documentation/spi/spi-lm70llp b/Documentation/spi/spi-lm70llp index 154bd02220b9..34a9cfd746bd 100644 --- a/Documentation/spi/spi-lm70llp +++ b/Documentation/spi/spi-lm70llp @@ -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 diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index cd05994a49e6..3197fc83bc51 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -1,12 +1,13 @@ -Documentation for /proc/sys/vm/* kernel version 2.2.10 +Documentation for /proc/sys/vm/* kernel version 2.6.29 (c) 1998, 1999, Rik van Riel <riel@nl.linux.org> + (c) 2008 Peter W. Morreale <pmorreale@novell.com> For general info and legal blurb, please look in README. ============================================================== This file contains the documentation for the sysctl files in -/proc/sys/vm and is valid for Linux kernel version 2.2. +/proc/sys/vm and is valid for Linux kernel version 2.6.29. The files in this directory can be used to tune the operation of the virtual memory (VM) subsystem of the Linux kernel and @@ -16,179 +17,274 @@ Default values and initialization routines for most of these files can be found in mm/swap.c. Currently, these files are in /proc/sys/vm: -- overcommit_memory -- page-cluster -- dirty_ratio + +- block_dump +- dirty_background_bytes - dirty_background_ratio +- dirty_bytes - dirty_expire_centisecs +- dirty_ratio - dirty_writeback_centisecs -- highmem_is_dirtyable (only if CONFIG_HIGHMEM set) +- drop_caches +- hugepages_treat_as_movable +- hugetlb_shm_group +- laptop_mode +- legacy_va_layout +- lowmem_reserve_ratio - max_map_count - min_free_kbytes -- laptop_mode -- block_dump -- drop-caches -- zone_reclaim_mode -- min_unmapped_ratio - min_slab_ratio -- panic_on_oom -- oom_dump_tasks -- oom_kill_allocating_task -- mmap_min_address -- numa_zonelist_order +- min_unmapped_ratio +- mmap_min_addr - nr_hugepages - nr_overcommit_hugepages +- nr_pdflush_threads +- nr_trim_pages (only if CONFIG_MMU=n) +- numa_zonelist_order +- oom_dump_tasks +- oom_kill_allocating_task +- overcommit_memory +- overcommit_ratio +- page-cluster +- panic_on_oom +- percpu_pagelist_fraction +- stat_interval +- swappiness +- vfs_cache_pressure +- zone_reclaim_mode + ============================================================== -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: +block_dump -See Documentation/filesystems/proc.txt +block_dump enables block I/O debugging when set to a nonzero value. More +information on block I/O debugging is in Documentation/laptops/laptop-mode.txt. ============================================================== -overcommit_memory: +dirty_background_bytes -This value contains a flag that enables memory overcommitment. +Contains the amount of dirty memory at which the pdflush background writeback +daemon will start writeback. -When this flag is 0, the kernel attempts to estimate the amount -of free memory left when userspace requests more memory. +If dirty_background_bytes is written, dirty_background_ratio becomes a function +of its value (dirty_background_bytes / the amount of dirtyable system memory). -When this flag is 1, the kernel pretends there is always enough -memory until it actually runs out. +============================================================== -When this flag is 2, the kernel uses a "never overcommit" -policy that attempts to prevent any overcommit of memory. +dirty_background_ratio -This feature can be very useful because there are a lot of -programs that malloc() huge amounts of memory "just-in-case" -and don't use much of it. +Contains, as a percentage of total system memory, the number of pages at which +the pdflush background writeback daemon will start writing out dirty data. -The default value is 0. +============================================================== -See Documentation/vm/overcommit-accounting and -security/commoncap.c::cap_vm_enough_memory() for more information. +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). ============================================================== -overcommit_ratio: +dirty_expire_centisecs -When overcommit_memory is set to 2, the committed address -space is not permitted to exceed swap plus this percentage -of physical RAM. See above. +This tunable is used to define when dirty data is old enough to be eligible +for writeout by the pdflush daemons. It is expressed in 100'ths of a second. +Data which has been dirty in-memory for longer than this interval will be +written out next time a pdflush daemon wakes up. + +============================================================== + +dirty_ratio + +Contains, as a percentage of total system memory, the number of pages at which +a process which is generating disk writes will itself start writing out dirty +data. ============================================================== -page-cluster: +dirty_writeback_centisecs -The Linux VM subsystem avoids excessive disk seeks by reading -multiple pages on a page fault. The number of pages it reads -is dependent on the amount of memory in your machine. +The pdflush writeback daemons will periodically wake up and write `old' data +out to disk. This tunable expresses the interval between those wakeups, in +100'ths of a second. -The number of pages the kernel reads in at once is equal to -2 ^ page-cluster. Values above 2 ^ 5 don't make much sense -for swap because we only cluster swap data in 32-page groups. +Setting this to zero disables periodic writeback altogether. ============================================================== -max_map_count: +drop_caches -This file contains the maximum number of memory map areas a process -may have. Memory map areas are used as a side-effect of calling -malloc, directly by mmap and mprotect, and also when loading shared -libraries. +Writing to this will cause the kernel to drop clean caches, dentries and +inodes from memory, causing that memory to become free. -While most applications need less than a thousand maps, certain -programs, particularly malloc debuggers, may consume lots of them, -e.g., up to one or two maps per allocation. +To free pagecache: + echo 1 > /proc/sys/vm/drop_caches +To free dentries and inodes: + echo 2 > /proc/sys/vm/drop_caches +To free pagecache, dentries and inodes: + echo 3 > /proc/sys/vm/drop_caches -The default value is 65536. +As this is a non-destructive operation and dirty objects are not freeable, the +user should run `sync' first. ============================================================== -min_free_kbytes: +hugepages_treat_as_movable -This is used to force the Linux VM to keep a minimum number -of kilobytes free. The VM uses this number to compute a pages_min -value for each lowmem zone in the system. Each lowmem zone gets -a number of reserved free pages based proportionally on its size. +This parameter is only useful when kernelcore= is specified at boot time to +create ZONE_MOVABLE for pages that may be reclaimed or migrated. Huge pages +are not movable so are not normally allocated from ZONE_MOVABLE. A non-zero +value written to hugepages_treat_as_movable allows huge pages to be allocated +from ZONE_MOVABLE. -Some minimal amount of memory is needed to satisfy PF_MEMALLOC -allocations; if you set this to lower than 1024KB, your system will -become subtly broken, and prone to deadlock under high loads. - -Setting this too high will OOM your machine instantly. +Once enabled, the ZONE_MOVABLE is treated as an area of memory the huge +pages pool can easily grow or shrink within. Assuming that applications are +not running that mlock() a lot of memory, it is likely the huge pages pool +can grow to the size of ZONE_MOVABLE by repeatedly entering the desired value +into nr_hugepages and triggering page reclaim. ============================================================== -percpu_pagelist_fraction +hugetlb_shm_group -This is the fraction of pages at most (high mark pcp->high) in each zone that -are allocated for each per cpu page list. The min value for this is 8. It -means that we don't allow more than 1/8th of pages in each zone to be -allocated in any single per_cpu_pagelist. This entry only changes the value -of hot per cpu pagelists. User can specify a number like 100 to allocate -1/100th of each zone to each per cpu page list. +hugetlb_shm_group contains group id that is allowed to create SysV +shared memory segment using hugetlb page. -The batch value of each per cpu pagelist is also updated as a result. It is -set to pcp->high/4. The upper limit of batch is (PAGE_SHIFT * 8) +============================================================== -The initial value is zero. Kernel does not use this value at boot time to set -the high water marks for each per cpu page list. +laptop_mode -=============================================================== +laptop_mode is a knob that controls "laptop mode". All the things that are +controlled by this knob are discussed in Documentation/laptops/laptop-mode.txt. -zone_reclaim_mode: +============================================================== -Zone_reclaim_mode allows someone to set more or less aggressive approaches to -reclaim memory when a zone runs out of memory. If it is set to zero then no -zone reclaim occurs. Allocations will be satisfied from other zones / nodes -in the system. +legacy_va_layout -This is value ORed together of +If non-zero, this sysctl disables the new 32-bit mmap mmap layout - the kernel +will use the legacy (2.4) layout for all processes. -1 = Zone reclaim on -2 = Zone reclaim writes dirty pages out -4 = Zone reclaim swaps pages +============================================================== -zone_reclaim_mode is set during bootup to 1 if it is determined that pages -from remote zones will cause a measurable performance reduction. The -page allocator will then reclaim easily reusable pages (those page -cache pages that are currently not used) before allocating off node pages. +lowmem_reserve_ratio + +For some specialised workloads on highmem machines it is dangerous for +the kernel to allow process memory to be allocated from the "lowmem" +zone. This is because that memory could then be pinned via the mlock() +system call, or by unavailability of swapspace. + +And on large highmem machines this lack of reclaimable lowmem memory +can be fatal. + +So the Linux page allocator has a mechanism which prevents allocations +which _could_ use highmem from using too much lowmem. This means that +a certain amount of lowmem is defended from the possibility of being +captured into pinned user memory. + +(The same argument applies to the old 16 megabyte ISA DMA region. This +mechanism will also defend that region from allocations which could use +highmem or lowmem). + +The `lowmem_reserve_ratio' tunable determines how aggressive the kernel is +in defending these lower zones. + +If you have a machine which uses highmem or ISA DMA and your +applications are using mlock(), or if you are running with no swap then +you probably should change the lowmem_reserve_ratio setting. + +The lowmem_reserve_ratio is an array. You can see them by reading this file. +- +% cat /proc/sys/vm/lowmem_reserve_ratio +256 256 32 +- +Note: # of this elements is one fewer than number of zones. Because the highest + zone's value is not necessary for following calculation. + +But, these values are not used directly. The kernel calculates # of protection +pages for each zones from them. These are shown as array of protection pages +in /proc/zoneinfo like followings. (This is an example of x86-64 box). +Each zone has an array of protection pages like this. + +- +Node 0, zone DMA + pages free 1355 + min 3 + low 3 + high 4 + : + : + numa_other 0 + protection: (0, 2004, 2004, 2004) + ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + pagesets + cpu: 0 pcp: 0 + : +- +These protections are added to score to judge whether this zone should be used +for page allocation or should be reclaimed. + +In this example, if normal pages (index=2) are required to this DMA zone and +pages_high is used for watermark, the kernel judges this zone should not be +used because pages_free(1355) is smaller than watermark + protection[2] +(4 + 2004 = 2008). If this protection value is 0, this zone would be used for +normal page requirement. If requirement is DMA zone(index=0), protection[0] +(=0) is used. + +zone[i]'s protection[j] is calculated by following expression. + +(i < j): + zone[i]->protection[j] + = (total sums of present_pages from zone[i+1] to zone[j] on the node) + / lowmem_reserve_ratio[i]; +(i = j): + (should not be protected. = 0; +(i > j): + (not necessary, but looks 0) + +The default values of lowmem_reserve_ratio[i] are + 256 (if zone[i] means DMA or DMA32 zone) + 32 (others). +As above expression, they are reciprocal number of ratio. +256 means 1/256. # of protection pages becomes about "0.39%" of total present +pages of higher zones on the node. + +If you would like to protect more pages, smaller values are effective. +The minimum value is 1 (1/1 -> 100%). -It may be beneficial to switch off zone reclaim if the system is -used for a file server and all of memory should be used for caching files -from disk. In that case the caching effect is more important than -data locality. +============================================================== -Allowing zone reclaim to write out pages stops processes that are -writing large amounts of data from dirtying pages on other nodes. Zone -reclaim will write out dirty pages if a zone fills up and so effectively -throttle the process. This may decrease the performance of a single process -since it cannot use all of system memory to buffer the outgoing writes -anymore but it preserve the memory on other nodes so that the performance -of other processes running on other nodes will not be affected. +max_map_count: -Allowing regular swap effectively restricts allocations to the local -node unless explicitly overridden by memory policies or cpuset -configurations. +This file contains the maximum number of memory map areas a process +may have. Memory map areas are used as a side-effect of calling +malloc, directly by mmap and mprotect, and also when loading shared +libraries. -============================================================= +While most applications need less than a thousand maps, certain +programs, particularly malloc debuggers, may consume lots of them, +e.g., up to one or two maps per allocation. -min_unmapped_ratio: +The default value is 65536. -This is available only on NUMA kernels. +============================================================== -A percentage of the total pages in each zone. Zone reclaim will only -occur if more than this percentage of pages are file backed and unmapped. -This is to insure that a minimal amount of local pages is still available for -file I/O even if the node is overallocated. +min_free_kbytes: -The default is 1 percent. +This is used to force the Linux VM to keep a minimum number +of kilobytes free. The VM uses this number to compute a pages_min +value for each lowmem zone in the system. Each lowmem zone gets +a number of reserved free pages based proportionally on its size. + +Some minimal amount of memory is needed to satisfy PF_MEMALLOC +allocations; if you set this to lower than 1024KB, your system will +become subtly broken, and prone to deadlock under high loads. + +Setting this too high will OOM your machine instantly. ============================================================= @@ -210,82 +306,73 @@ and may not be fast. ============================================================= -panic_on_oom +min_unmapped_ratio: -This enables or disables panic on out-of-memory feature. +This is available only on NUMA kernels. -If this is set to 0, the kernel will kill some rogue process, -called oom_killer. Usually, oom_killer can kill rogue processes and -system will survive. +A percentage of the total pages in each zone. Zone reclaim will only +occur if more than this percentage of pages are file backed and unmapped. +This is to insure that a minimal amount of local pages is still available for +file I/O even if the node is overallocated. -If this is set to 1, the kernel panics when out-of-memory happens. -However, if a process limits using nodes by mempolicy/cpusets, -and those nodes become memory exhaustion status, one process -may be killed by oom-killer. No panic occurs in this case. -Because other nodes' memory may be free. This means system total status -may be not fatal yet. +The default is 1 percent. -If this is set to 2, the kernel panics compulsorily even on the -above-mentioned. +============================================================== -The default value is 0. -1 and 2 are for failover of clustering. Please select either -according to your policy of failover. +mmap_min_addr -============================================================= +This file indicates the amount of address space which a user process will +be restricted from mmaping. Since kernel null dereference bugs could +accidentally operate based on the information in the first couple of pages +of memory userspace processes should not be allowed to write to them. By +default this value is set to 0 and no protections will be enforced by the +security module. Setting this value to something like 64k will allow the +vast majority of applications to work correctly and provide defense in depth +against future potential kernel bugs. -oom_dump_tasks +============================================================== -Enables a system-wide task dump (excluding kernel threads) to be -produced when the kernel performs an OOM-killing and includes such -information as pid, uid, tgid, vm size, rss, cpu, oom_adj score, and -name. This is helpful to determine why the OOM killer was invoked -and to identify the rogue task that caused it. +nr_hugepages -If this is set to zero, this information is suppressed. On very -large systems with thousands of tasks it may not be feasible to dump -the memory state information for each one. Such systems should not -be forced to incur a performance penalty in OOM conditions when the -information may not be desired. +Change the minimum size of the hugepage pool. -If this is set to non-zero, this information is shown whenever the -OOM killer actually kills a memory-hogging task. +See Documentation/vm/hugetlbpage.txt -The default value is 0. +============================================================== -============================================================= +nr_overcommit_hugepages -oom_kill_allocating_task +Change the maximum size of the hugepage pool. The maximum is +nr_hugepages + nr_overcommit_hugepages. -This enables or disables killing the OOM-triggering task in -out-of-memory situations. +See Documentation/vm/hugetlbpage.txt -If this is set to zero, the OOM killer will scan through the entire -tasklist and select a task based on heuristics to kill. This normally -selects a rogue memory-hogging task that frees up a large amount of -memory when killed. +============================================================== -If this is set to non-zero, the OOM killer simply kills the task that -triggered the out-of-memory condition. This avoids the expensive -tasklist scan. +nr_pdflush_threads -If panic_on_oom is selected, it takes precedence over whatever value -is used in oom_kill_allocating_task. +The current number of pdflush threads. This value is read-only. +The value changes according to the number of dirty pages in the system. -The default value is 0. +When neccessary, additional pdflush threads are created, one per second, up to +nr_pdflush_threads_max. ============================================================== -mmap_min_addr +nr_trim_pages -This file indicates the amount of address space which a user process will -be restricted from mmaping. Since kernel null dereference bugs could -accidentally operate based on the information in the first couple of pages -of memory userspace processes should not be allowed to write to them. By -default this value is set to 0 and no protections will be enforced by the -security module. Setting this value to something like 64k will allow the -vast majority of applications to work correctly and provide defense in depth -against future potential kernel bugs. +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. ============================================================== @@ -334,17 +421,199 @@ this is causing problems for your system/application. ============================================================== -nr_hugepages +oom_dump_tasks -Change the minimum size of the hugepage pool. +Enables a system-wide task dump (excluding kernel threads) to be +produced when the kernel performs an OOM-killing and includes such +information as pid, uid, tgid, vm size, rss, cpu, oom_adj score, and +name. This is helpful to determine why the OOM killer was invoked +and to identify the rogue task that caused it. -See Documentation/vm/hugetlbpage.txt +If this is set to zero, this information is suppressed. On very +large systems with thousands of tasks it may not be feasible to dump +the memory state information for each one. Such systems should not +be forced to incur a performance penalty in OOM conditions when the +information may not be desired. + +If this is set to non-zero, this information is shown whenever the +OOM killer actually kills a memory-hogging task. + +The default value is 0. ============================================================== -nr_overcommit_hugepages +oom_kill_allocating_task -Change the maximum size of the hugepage pool. The maximum is -nr_hugepages + nr_overcommit_hugepages. +This enables or disables killing the OOM-triggering task in +out-of-memory situations. -See Documentation/vm/hugetlbpage.txt +If this is set to zero, the OOM killer will scan through the entire +tasklist and select a task based on heuristics to kill. This normally +selects a rogue memory-hogging task that frees up a large amount of +memory when killed. + +If this is set to non-zero, the OOM killer simply kills the task that +triggered the out-of-memory condition. This avoids the expensive +tasklist scan. + +If panic_on_oom is selected, it takes precedence over whatever value +is used in oom_kill_allocating_task. + +The default value is 0. + +============================================================== + +overcommit_memory: + +This value contains a flag that enables memory overcommitment. + +When this flag is 0, the kernel attempts to estimate the amount +of free memory left when userspace requests more memory. + +When this flag is 1, the kernel pretends there is always enough +memory until it actually runs out. + +When this flag is 2, the kernel uses a "never overcommit" +policy that attempts to prevent any overcommit of memory. + +This feature can be very useful because there are a lot of +programs that malloc() huge amounts of memory "just-in-case" +and don't use much of it. + +The default value is 0. + +See Documentation/vm/overcommit-accounting and +security/commoncap.c::cap_vm_enough_memory() for more information. + +============================================================== + +overcommit_ratio: + +When overcommit_memory is set to 2, the committed address +space is not permitted to exceed swap plus this percentage +of physical RAM. See above. + +============================================================== + +page-cluster + +page-cluster controls the number of pages which are written to swap in +a single attempt. The swap I/O size. + +It is a logarithmic value - setting it to zero means "1 page", setting +it to 1 means "2 pages", setting it to 2 means "4 pages", etc. + +The default value is three (eight pages at a time). There may be some +small benefits in tuning this to a different value if your workload is +swap-intensive. + +============================================================= + +panic_on_oom + +This enables or disables panic on out-of-memory feature. + +If this is set to 0, the kernel will kill some rogue process, +called oom_killer. Usually, oom_killer can kill rogue processes and +system will survive. + +If this is set to 1, the kernel panics when out-of-memory happens. +However, if a process limits using nodes by mempolicy/cpusets, +and those nodes become memory exhaustion status, one process +may be killed by oom-killer. No panic occurs in this case. +Because other nodes' memory may be free. This means system total status +may be not fatal yet. + +If this is set to 2, the kernel panics compulsorily even on the +above-mentioned. + +The default value is 0. +1 and 2 are for failover of clustering. Please select either +according to your policy of failover. + +============================================================= + +percpu_pagelist_fraction + +This is the fraction of pages at most (high mark pcp->high) in each zone that +are allocated for each per cpu page list. The min value for this is 8. It +means that we don't allow more than 1/8th of pages in each zone to be +allocated in any single per_cpu_pagelist. This entry only changes the value +of hot per cpu pagelists. User can specify a number like 100 to allocate +1/100th of each zone to each per cpu page list. + +The batch value of each per cpu pagelist is also updated as a result. It is +set to pcp->high/4. The upper limit of batch is (PAGE_SHIFT * 8) + +The initial value is zero. Kernel does not use this value at boot time to set +the high water marks for each per cpu page list. + +============================================================== + +stat_interval + +The time interval between which vm statistics are updated. The default +is 1 second. + +============================================================== + +swappiness + +This control is used to define how aggressive the kernel will swap +memory pages. Higher values will increase agressiveness, lower values +descrease the amount of swap. + +The default value is 60. + +============================================================== + +vfs_cache_pressure +------------------ + +Controls the tendency of the kernel to reclaim the memory which is used for +caching of directory and inode objects. + +At the default value of vfs_cache_pressure=100 the kernel will attempt to +reclaim dentries and inodes at a "fair" rate with respect to pagecache and +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. + +============================================================== + +zone_reclaim_mode: + +Zone_reclaim_mode allows someone to set more or less aggressive approaches to +reclaim memory when a zone runs out of memory. If it is set to zero then no +zone reclaim occurs. Allocations will be satisfied from other zones / nodes +in the system. + +This is value ORed together of + +1 = Zone reclaim on +2 = Zone reclaim writes dirty pages out +4 = Zone reclaim swaps pages + +zone_reclaim_mode is set during bootup to 1 if it is determined that pages +from remote zones will cause a measurable performance reduction. The +page allocator will then reclaim easily reusable pages (those page +cache pages that are currently not used) before allocating off node pages. + +It may be beneficial to switch off zone reclaim if the system is +used for a file server and all of memory should be used for caching files +from disk. In that case the caching effect is more important than +data locality. + +Allowing zone reclaim to write out pages stops processes that are +writing large amounts of data from dirtying pages on other nodes. Zone +reclaim will write out dirty pages if a zone fills up and so effectively +throttle the process. This may decrease the performance of a single process +since it cannot use all of system memory to buffer the outgoing writes +anymore but it preserve the memory on other nodes so that the performance +of other processes running on other nodes will not be affected. + +Allowing regular swap effectively restricts allocations to the local +node unless explicitly overridden by memory policies or cpuset +configurations. + +============ End of Document ================================= diff --git a/Documentation/sysrq.txt b/Documentation/sysrq.txt index 10a0263ebb3f..9e592c718afb 100644 --- a/Documentation/sysrq.txt +++ b/Documentation/sysrq.txt @@ -1,6 +1,5 @@ Linux Magic System Request Key Hacks Documentation for sysrq.c -Last update: 2007-AUG-04 * What is the magic SysRq key? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -211,6 +210,24 @@ within a function called by handle_sysrq, you must be aware that you are in a lock (you are also in an interrupt handler, which means don't sleep!), so you must call __handle_sysrq_nolock instead. +* When I hit a SysRq key combination only the header appears on the console? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Sysrq output is subject to the same console loglevel control as all +other console output. This means that if the kernel was booted 'quiet' +as is common on distro kernels the output may not appear on the actual +console, even though it will appear in the dmesg buffer, and be accessible +via the dmesg command and to the consumers of /proc/kmsg. As a specific +exception the header line from the sysrq command is passed to all console +consumers as if the current loglevel was maximum. If only the header +is emitted it is almost certain that the kernel loglevel is too low. +Should you require the output on the console channel then you will need +to temporarily up the console loglevel using alt-sysrq-8 or: + + echo 8 > /proc/sysrq-trigger + +Remember to return the loglevel to normal after triggering the sysrq +command you are interested in. + * I have more questions, who can I ask? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ And I'll answer any questions about the registration system you got, also diff --git a/Documentation/usb/power-management.txt b/Documentation/usb/power-management.txt index e48ea1d51010..ad642615ad4c 100644 --- a/Documentation/usb/power-management.txt +++ b/Documentation/usb/power-management.txt @@ -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 diff --git a/Documentation/w1/masters/00-INDEX b/Documentation/w1/masters/00-INDEX index 7b0ceaaad7af..d63fa024ac05 100644 --- a/Documentation/w1/masters/00-INDEX +++ b/Documentation/w1/masters/00-INDEX @@ -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. diff --git a/Documentation/w1/masters/mxc-w1 b/Documentation/w1/masters/mxc-w1 new file mode 100644 index 000000000000..97f6199a7f39 --- /dev/null +++ b/Documentation/w1/masters/mxc-w1 @@ -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> diff --git a/Documentation/w1/w1.netlink b/Documentation/w1/w1.netlink index 3640c7c87d45..804445f745ed 100644 --- a/Documentation/w1/w1.netlink +++ b/Documentation/w1/w1.netlink @@ -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. diff --git a/Documentation/wimax/README.i2400m b/Documentation/wimax/README.i2400m new file mode 100644 index 000000000000..7dffd8919cb0 --- /dev/null +++ b/Documentation/wimax/README.i2400m @@ -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. diff --git a/Documentation/wimax/README.wimax b/Documentation/wimax/README.wimax new file mode 100644 index 000000000000..b78c4378084e --- /dev/null +++ b/Documentation/wimax/README.wimax @@ -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. diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index fcdc62b3c3d8..7b4596ac4120 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -44,7 +44,7 @@ Protocol 2.07: (Kernel 2.6.24) Added paravirtualised boot protocol. and KEEP_SEGMENTS flag in load_flags. Protocol 2.08: (Kernel 2.6.26) Added crc32 checksum and ELF format - payload. Introduced payload_offset and payload length + payload. Introduced payload_offset and payload_length fields to aid in locating the payload. Protocol 2.09: (Kernel 2.6.26) Added a field of 64-bit physical |