Merge http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm into for-rmk

CREDITS

@@ -317,6 +317,14 @@ S: 2322 37th Ave SW
 S: Seattle, Washington 98126-2010
 S: USA
 
+N: Muli Ben-Yehuda
+E: mulix@mulix.org
+E: muli@il.ibm.com
+W: http://www.mulix.org
+D: trident OSS sound driver, x86-64 dma-ops and Calgary IOMMU,
+D: KVM and Xen bits and other misc. hackery.
+S: Haifa, Israel
+
 N: Johannes Berg
 E: johannes@sipsolutions.net
 W: http://johannes.sipsolutions.net/
@@ -3344,8 +3352,7 @@ S: Spain
 N: Linus Torvalds
 E: torvalds@linux-foundation.org
 D: Original kernel hacker
-S: 12725 SW Millikan Way, Suite 400
-S: Beaverton, Oregon 97005
+S: Portland, Oregon 97005
 S: USA
 
 N: Marcelo Tosatti

Documentation/00-INDEX

@@ -89,8 +89,6 @@ cciss.txt
 	- info, major/minor #'s for Compaq's SMART Array Controllers.
 cdrom/
 	- directory with information on the CD-ROM drivers that Linux has.
-cli-sti-removal.txt
-	- cli()/sti() removal guide.
 computone.txt
 	- info on Computone Intelliport II/Plus Multiport Serial Driver.
 connector/
@@ -361,8 +359,6 @@ telephony/
 	- directory with info on telephony (e.g. voice over IP) support.
 time_interpolators.txt
 	- info on time interpolators.
-tipar.txt
-	- information about Parallel link cable for Texas Instruments handhelds.
 tty.txt
 	- guide to the locking policies of the tty layer.
 uml/

Documentation/ABI/testing/sysfs-class-regulator

+What:		/sys/class/regulator/.../state
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		state. This holds the regulator output state.
+
+		This will be one of the following strings:
+
+		'enabled'
+		'disabled'
+		'unknown'
+
+		'enabled' means the regulator output is ON and is supplying
+		power to the system.
+
+		'disabled' means the regulator output is OFF and is not
+		supplying power to the system..
+
+		'unknown' means software cannot determine the state.
+
+		NOTE: this field can be used in conjunction with microvolts
+		and microamps to determine regulator output levels.
+
+
+What:		/sys/class/regulator/.../type
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		type. This holds the regulator type.
+
+		This will be one of the following strings:
+
+		'voltage'
+		'current'
+		'unknown'
+
+		'voltage' means the regulator output voltage can be controlled
+		by software.
+
+		'current' means the regulator output current limit can be
+		controlled by software.
+
+		'unknown' means software cannot control either voltage or
+		current limit.
+
+
+What:		/sys/class/regulator/.../microvolts
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		microvolts. This holds the regulator output voltage setting
+		measured in microvolts (i.e. E-6 Volts).
+
+		NOTE: This value should not be used to determine the regulator
+		output voltage level as this value is the same regardless of
+		whether the regulator is enabled or disabled.
+
+
+What:		/sys/class/regulator/.../microamps
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		microamps. This holds the regulator output current limit
+		setting measured in microamps (i.e. E-6 Amps).
+
+		NOTE: This value should not be used to determine the regulator
+		output current level as this value is the same regardless of
+		whether the regulator is enabled or disabled.
+
+
+What:		/sys/class/regulator/.../opmode
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		opmode. This holds the regulator operating mode setting.
+
+		The opmode value can be one of the following strings:
+
+		'fast'
+		'normal'
+		'idle'
+		'standby'
+		'unknown'
+
+		The modes are described in include/linux/regulator/regulator.h
+
+		NOTE: This value should not be used to determine the regulator
+		output operating mode as this value is the same regardless of
+		whether the regulator is enabled or disabled.
+
+
+What:		/sys/class/regulator/.../min_microvolts
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		min_microvolts. This holds the minimum safe working regulator
+		output voltage setting for this domain measured in microvolts.
+
+		NOTE: this will return the string 'constraint not defined' if
+		the power domain has no min microvolts constraint defined by
+		platform code.
+
+
+What:		/sys/class/regulator/.../max_microvolts
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		max_microvolts. This holds the maximum safe working regulator
+		output voltage setting for this domain measured in microvolts.
+
+		NOTE: this will return the string 'constraint not defined' if
+		the power domain has no max microvolts constraint defined by
+		platform code.
+
+
+What:		/sys/class/regulator/.../min_microamps
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		min_microamps. This holds the minimum safe working regulator
+		output current limit setting for this domain measured in
+		microamps.
+
+		NOTE: this will return the string 'constraint not defined' if
+		the power domain has no min microamps constraint defined by
+		platform code.
+
+
+What:		/sys/class/regulator/.../max_microamps
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		max_microamps. This holds the maximum safe working regulator
+		output current limit setting for this domain measured in
+		microamps.
+
+		NOTE: this will return the string 'constraint not defined' if
+		the power domain has no max microamps constraint defined by
+		platform code.
+
+
+What:		/sys/class/regulator/.../num_users
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		num_users. This holds the number of consumer devices that
+		have called regulator_enable() on this regulator.
+
+
+What:		/sys/class/regulator/.../requested_microamps
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory will contain a field called
+		requested_microamps. This holds the total requested load
+		current in microamps for this regulator from all its consumer
+		devices.
+
+
+What:		/sys/class/regulator/.../parent
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Some regulator directories will contain a link called parent.
+		This points to the parent or supply regulator if one exists.
+
+What:		/sys/class/regulator/.../suspend_mem_microvolts
+Date:		May 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory 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.
+
+What:		/sys/class/regulator/.../suspend_disk_microvolts
+Date:		May 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory 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.
+
+What:		/sys/class/regulator/.../suspend_standby_microvolts
+Date:		May 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory 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.
+
+What:		/sys/class/regulator/.../suspend_mem_mode
+Date:		May 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory 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.
+
+What:		/sys/class/regulator/.../suspend_disk_mode
+Date:		May 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory 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.
+
+What:		/sys/class/regulator/.../suspend_standby_mode
+Date:		May 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory 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.
+
+What:		/sys/class/regulator/.../suspend_mem_state
+Date:		May 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory 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:
+
+		'enabled'
+		'disabled'
+		'not defined'
+
+What:		/sys/class/regulator/.../suspend_disk_state
+Date:		May 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory 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:
+
+		'enabled'
+		'disabled'
+		'not defined'
+
+What:		/sys/class/regulator/.../suspend_standby_state
+Date:		May 2008
+KernelVersion:	2.6.26
+Contact:	Liam Girdwood <lg@opensource.wolfsonmicro.com>
+Description:
+		Each regulator directory 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:
+
+		'enabled'
+		'disabled'
+		'not defined'

Documentation/ABI/testing/sysfs-dev

+What:		/sys/dev
+Date:		April 2008
+KernelVersion:	2.6.26
+Contact:	Dan Williams <dan.j.williams@intel.com>
+Description:	The /sys/dev tree provides a method to look up the sysfs
+		path for a device using the information returned from
+		stat(2).  There are two directories, 'block' and 'char',
+		beneath /sys/dev containing symbolic links with names of
+		the form "<major>:<minor>".  These links point to the
+		corresponding sysfs path for the given device.
+
+		Example:
+		$ readlink /sys/dev/block/8:32
+		../../block/sdc
+
+		Entries in /sys/dev/char and /sys/dev/block will be
+		dynamically created and destroyed as devices enter and
+		leave the system.
+
+Users:		mdadm <linux-raid@vger.kernel.org>

Documentation/ABI/testing/sysfs-devices-memory

+What:		/sys/devices/system/memory
+Date:		June 2008
+Contact:	Badari Pulavarty <pbadari@us.ibm.com>
+Description:
+		The /sys/devices/system/memory contains a snapshot of the
+		internal state of the kernel memory blocks. Files could be
+		added or removed dynamically to represent hot-add/remove
+		operations.
+
+Users:		hotplug memory add/remove tools
+		https://w3.opensource.ibm.com/projects/powerpc-utils/
+
+What:		/sys/devices/system/memory/memoryX/removable
+Date:		June 2008
+Contact:	Badari Pulavarty <pbadari@us.ibm.com>
+Description:
+		The file /sys/devices/system/memory/memoryX/removable
+		indicates whether this memory block is removable or not.
+		This is useful for a user-level agent to determine
+		identify removable sections of the memory before attempting
+		potentially expensive hot-remove memory operation
+
+Users:		hotplug memory remove tools
+		https://w3.opensource.ibm.com/projects/powerpc-utils/

Documentation/ABI/testing/sysfs-firmware-acpi

@@ -29,46 +29,46 @@ Description:
 
 		$ cd /sys/firmware/acpi/interrupts
 		$ grep . *
-		error:0
-		ff_gbl_lock:0
-		ff_pmtimer:0
-		ff_pwr_btn:0
-		ff_rt_clk:0
-		ff_slp_btn:0
-		gpe00:0
-		gpe01:0
-		gpe02:0
-		gpe03:0
-		gpe04:0
-		gpe05:0
-		gpe06:0
-		gpe07:0
-		gpe08:0
-		gpe09:174
-		gpe0A:0
-		gpe0B:0
-		gpe0C:0
-		gpe0D:0
-		gpe0E:0
-		gpe0F:0
-		gpe10:0
-		gpe11:60
-		gpe12:0
-		gpe13:0
-		gpe14:0
-		gpe15:0
-		gpe16:0
-		gpe17:0
-		gpe18:0
-		gpe19:7
-		gpe1A:0
-		gpe1B:0
-		gpe1C:0
-		gpe1D:0
-		gpe1E:0
-		gpe1F:0
-		gpe_all:241
-		sci:241
+		error:	     0
+		ff_gbl_lock:	   0   enable
+		ff_pmtimer:	  0  invalid
+		ff_pwr_btn:	  0   enable
+		ff_rt_clk:	 2  disable
+		ff_slp_btn:	  0  invalid
+		gpe00:	     0	invalid
+		gpe01:	     0	 enable
+		gpe02:	   108	 enable
+		gpe03:	     0	invalid
+		gpe04:	     0	invalid
+		gpe05:	     0	invalid
+		gpe06:	     0	 enable
+		gpe07:	     0	 enable
+		gpe08:	     0	invalid
+		gpe09:	     0	invalid
+		gpe0A:	     0	invalid
+		gpe0B:	     0	invalid
+		gpe0C:	     0	invalid
+		gpe0D:	     0	invalid
+		gpe0E:	     0	invalid
+		gpe0F:	     0	invalid
+		gpe10:	     0	invalid
+		gpe11:	     0	invalid
+		gpe12:	     0	invalid
+		gpe13:	     0	invalid
+		gpe14:	     0	invalid
+		gpe15:	     0	invalid
+		gpe16:	     0	invalid
+		gpe17:	  1084	 enable
+		gpe18:	     0	 enable
+		gpe19:	     0	invalid
+		gpe1A:	     0	invalid
+		gpe1B:	     0	invalid
+		gpe1C:	     0	invalid
+		gpe1D:	     0	invalid
+		gpe1E:	     0	invalid
+		gpe1F:	     0	invalid
+		gpe_all:    1192
+		sci:	1194
 
 		sci - The total number of times the ACPI SCI
 		has claimed an interrupt.
@@ -89,6 +89,13 @@ Description:
 
 		error - an interrupt that can't be accounted for above.
 
+		invalid: it's either a wakeup GPE or a GPE/Fixed Event that
+			doesn't have an event handler.
+
+		disable: the GPE/Fixed Event is valid but disabled.
+
+		enable: the GPE/Fixed Event is valid and enabled.
+
 		Root has permission to clear any of these counters.  Eg.
 		# echo 0 > gpe11
 
@@ -97,3 +104,43 @@ Description:
 
 		None of these counters has an effect on the function
 		of the system, they are simply statistics.
+
+		Besides this, user can also write specific strings to these files
+		to enable/disable/clear ACPI interrupts in user space, which can be
+		used to debug some ACPI interrupt storm issues.
+
+		Note that only writting to VALID GPE/Fixed Event is allowed,
+		i.e. user can only change the status of runtime GPE and
+		Fixed Event with event handler installed.
+
+		Let's take power button fixed event for example, please kill acpid
+		and other user space applications so that the machine won't shutdown
+		when pressing the power button.
+		# cat ff_pwr_btn
+		0
+		# press the power button for 3 times;
+		# cat ff_pwr_btn
+		3
+		# echo disable > ff_pwr_btn
+		# cat ff_pwr_btn
+		disable
+		# press the power button for 3 times;
+		# cat ff_pwr_btn
+		disable
+		# echo enable > ff_pwr_btn
+		# cat ff_pwr_btn
+		4
+		/*
+		 * this is because the status bit is set even if the enable bit is cleared,
+		 * and it triggers an ACPI fixed event when the enable bit is set again
+		 */
+		# press the power button for 3 times;
+		# cat ff_pwr_btn
+		7
+		# echo disable > ff_pwr_btn
+		# press the power button for 3 times;
+		# echo clear > ff_pwr_btn	/* clear the status bit */
+		# echo disable > ff_pwr_btn
+		# cat ff_pwr_btn
+		7
+

Documentation/ABI/testing/sysfs-kernel-mm

+What:		/sys/kernel/mm
+Date:		July 2008
+Contact:	Nishanth Aravamudan <nacc@us.ibm.com>, VM maintainers
+Description:
+		/sys/kernel/mm/ should contain any and all VM
+		related information in /sys/kernel/.

Documentation/ABI/testing/sysfs-kernel-mm-hugepages

+What:		/sys/kernel/mm/hugepages/
+Date:		June 2008
+Contact:	Nishanth Aravamudan <nacc@us.ibm.com>, hugetlb maintainers
+Description:
+		/sys/kernel/mm/hugepages/ contains a number of subdirectories
+		of the form hugepages-<size>kB, where <size> is the page size
+		of the hugepages supported by the kernel/CPU combination.
+
+		Under these directories are a number of files:
+			nr_hugepages
+			nr_overcommit_hugepages
+			free_hugepages
+			surplus_hugepages
+			resv_hugepages
+		See Documentation/vm/hugetlbpage.txt for details.

Documentation/CodingStyle

@@ -474,25 +474,29 @@ make a good program).
 So, you can either get rid of GNU emacs, or change it to use saner
 values.  To do the latter, you can stick the following in your .emacs file:
 
-(defun linux-c-mode ()
-  "C mode with adjusted defaults for use with the Linux kernel."
-  (interactive)
-  (c-mode)
-  (c-set-style "K&R")
-  (setq tab-width 8)
-  (setq indent-tabs-mode t)
-  (setq c-basic-offset 8))
-
-This will define the M-x linux-c-mode command.  When hacking on a
-module, if you put the string -*- linux-c -*- somewhere on the first
-two lines, this mode will be automatically invoked. Also, you may want
-to add
-
-(setq auto-mode-alist (cons '("/usr/src/linux.*/.*\\.[ch]$" . linux-c-mode)
-			auto-mode-alist))
-
-to your .emacs file if you want to have linux-c-mode switched on
-automagically when you edit source files under /usr/src/linux.
+(defun c-lineup-arglist-tabs-only (ignored)
+  "Line up argument lists by tabs, not spaces"
+  (let* ((anchor (c-langelem-pos c-syntactic-element))
+	 (column (c-langelem-2nd-pos c-syntactic-element))
+	 (offset (- (1+ column) anchor))
+	 (steps (floor offset c-basic-offset)))
+    (* (max steps 1)
+       c-basic-offset)))
+
+(add-hook 'c-mode-hook
+          (lambda ()
+            (let ((filename (buffer-file-name)))
+              ;; Enable kernel mode for the appropriate files
+              (when (and filename
+                         (string-match "~/src/linux-trees" filename))
+                (setq indent-tabs-mode t)
+                (c-set-style "linux")
+                (c-set-offset 'arglist-cont-nonempty
+                              '(c-lineup-gcc-asm-reg
+                                c-lineup-arglist-tabs-only))))))
+
+This will make emacs go better with the kernel coding style for C
+files below ~/src/linux-trees.
 
 But even if you fail in getting emacs to do sane formatting, not
 everything is lost: use "indent".

Documentation/DMA-API.txt

@@ -298,10 +298,10 @@ recommended that you never use these unless you really know what the
 cache width is.
 
 int
-dma_mapping_error(dma_addr_t dma_addr)
+dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 
 int
-pci_dma_mapping_error(dma_addr_t dma_addr)
+pci_dma_mapping_error(struct pci_dev *hwdev, dma_addr_t dma_addr)
 
 In some circumstances dma_map_single and dma_map_page will fail to create
 a mapping. A driver can check for these errors by testing the returned

Documentation/DMA-attributes.txt

@@ -22,3 +22,12 @@ ready and available in memory.  The DMA of the "completion indication"
 could race with data DMA.  Mapping the memory used for completion
 indications with DMA_ATTR_WRITE_BARRIER would prevent the race.
 
+DMA_ATTR_WEAK_ORDERING
+----------------------
+
+DMA_ATTR_WEAK_ORDERING specifies that reads and writes to the mapping
+may be weakly ordered, that is that reads and writes may pass each other.
+
+Since it is optional for platforms to implement DMA_ATTR_WEAK_ORDERING,
+those that do not will simply ignore the attribute and exhibit default
+behavior.

Documentation/DocBook/Makefile

@@ -12,7 +12,7 @@ DOCBOOKS := wanbook.xml z8530book.xml mcabook.xml videobook.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
+	    mac80211.xml debugobjects.xml sh.xml
 
 ###
 # The build process is as follows (targets):

Documentation/DocBook/gadget.tmpl

@@ -524,6 +524,44 @@ These utilities include endpoint autoconfiguration.
 <!-- !Edrivers/usb/gadget/epautoconf.c -->
 </sect1>
 
+<sect1 id="composite"><title>Composite Device Framework</title>
+
+<para>The core API is sufficient for writing drivers for composite
+USB devices (with more than one function in a given configuration),
+and also multi-configuration devices (also more than one function,
+but not necessarily sharing a given configuration).
+There is however an optional framework which makes it easier to
+reuse and combine functions.
+</para>
+
+<para>Devices using this framework provide a <emphasis>struct
+usb_composite_driver</emphasis>, which in turn provides one or
+more <emphasis>struct usb_configuration</emphasis> instances.
+Each such configuration includes at least one
+<emphasis>struct usb_function</emphasis>, which packages a user
+visible role such as "network link" or "mass storage device".
+Management functions may also exist, such as "Device Firmware
+Upgrade".
+</para>
+
+!Iinclude/linux/usb/composite.h
+!Edrivers/usb/gadget/composite.c
+
+</sect1>
+
+<sect1 id="functions"><title>Composite Device Functions</title>
+
+<para>At this writing, a few of the current gadget drivers have
+been converted to this framework.
+Near-term plans include converting all of them, except for "gadgetfs".
+</para>
+
+!Edrivers/usb/gadget/f_acm.c
+!Edrivers/usb/gadget/f_serial.c
+
+</sect1>
+
+
 </chapter>
 
 <chapter id="controllers"><title>Peripheral Controller Drivers</title>

Documentation/DocBook/kernel-locking.tmpl

@@ -219,10 +219,10 @@
    </para>
 
    <sect1 id="lock-intro">
-   <title>Three Main Types of Kernel Locks: Spinlocks, Mutexes and Semaphores</title>
+   <title>Two Main Types of Kernel Locks: Spinlocks and Mutexes</title>
 
    <para>
-     There are three main types of kernel locks.  The fundamental type
+     There are two main types of kernel locks.  The fundamental type
      is the spinlock 
      (<filename class="headerfile">include/asm/spinlock.h</filename>),
      which is a very simple single-holder lock: if you can't get the 
@@ -239,14 +239,6 @@
      can't sleep (see <xref linkend="sleeping-things"/>), and so have to
      use a spinlock instead.
    </para>
-   <para>
-     The third type is a semaphore
-     (<filename class="headerfile">include/linux/semaphore.h</filename>): it
-     can have more than one holder at any time (the number decided at
-     initialization time), although it is most commonly used as a
-     single-holder lock (a mutex).  If you can't get a semaphore, your
-     task will be suspended and later on woken up - just like for mutexes.
-   </para>
    <para>
      Neither type of lock is recursive: see
      <xref linkend="deadlock"/>.
@@ -278,7 +270,7 @@
     </para>
 
     <para>
-      Semaphores still exist, because they are required for
+      Mutexes still exist, because they are required for
       synchronization between <firstterm linkend="gloss-usercontext">user 
       contexts</firstterm>, as we will see below.
     </para>
@@ -289,18 +281,17 @@
 
      <para>
        If you have a data structure which is only ever accessed from
-       user context, then you can use a simple semaphore
-       (<filename>linux/linux/semaphore.h</filename>) to protect it.  This
-       is the most trivial case: you initialize the semaphore to the number 
-       of resources available (usually 1), and call
-       <function>down_interruptible()</function> to grab the semaphore, and 
-       <function>up()</function> to release it.  There is also a 
-       <function>down()</function>, which should be avoided, because it 
+       user context, then you can use a simple mutex
+       (<filename>include/linux/mutex.h</filename>) to protect it.  This
+       is the most trivial case: you initialize the mutex.  Then you can
+       call <function>mutex_lock_interruptible()</function> to grab the mutex,
+       and <function>mutex_unlock()</function> to release it.  There is also a 
+       <function>mutex_lock()</function>, which should be avoided, because it 
        will not return if a signal is received.
      </para>
 
      <para>
-       Example: <filename>linux/net/core/netfilter.c</filename> allows 
+       Example: <filename>net/netfilter/nf_sockopt.c</filename> allows 
        registration of new <function>setsockopt()</function> and 
        <function>getsockopt()</function> calls, with
        <function>nf_register_sockopt()</function>.  Registration and 
@@ -515,7 +506,7 @@
       <listitem>
 	<para>
           If you are in a process context (any syscall) and want to
-	lock other process out, use a semaphore.  You can take a semaphore
+	lock other process out, use a mutex.  You can take a mutex
 	and sleep (<function>copy_from_user*(</function> or
 	<function>kmalloc(x,GFP_KERNEL)</function>).
       </para>
@@ -662,7 +653,7 @@
 <entry>SLBH</entry>
 <entry>SLBH</entry>
 <entry>SLBH</entry>
-<entry>DI</entry>
+<entry>MLI</entry>
 <entry>None</entry>
 </row>
 
@@ -692,8 +683,8 @@
 <entry>spin_lock_bh</entry>
 </row>
 <row>
-<entry>DI</entry>
-<entry>down_interruptible</entry>
+<entry>MLI</entry>
+<entry>mutex_lock_interruptible</entry>
 </row>
 
 </tbody>
@@ -1310,7 +1301,7 @@ as Alan Cox says, <quote>Lock data, not code</quote>.
     <para>
       There is a coding bug where a piece of code tries to grab a
       spinlock twice: it will spin forever, waiting for the lock to
-      be released (spinlocks, rwlocks and semaphores are not
+      be released (spinlocks, rwlocks and mutexes are not
       recursive in Linux).  This is trivial to diagnose: not a
       stay-up-five-nights-talk-to-fluffy-code-bunnies kind of
       problem.
@@ -1335,7 +1326,7 @@ as Alan Cox says, <quote>Lock data, not code</quote>.
 
     <para>
       This complete lockup is easy to diagnose: on SMP boxes the
-      watchdog timer or compiling with <symbol>DEBUG_SPINLOCKS</symbol> set
+      watchdog timer or compiling with <symbol>DEBUG_SPINLOCK</symbol> set
       (<filename>include/linux/spinlock.h</filename>) will show this up 
       immediately when it happens.
     </para>
@@ -1558,7 +1549,7 @@ the amount of locking which needs to be done.
    <title>Read/Write Lock Variants</title>
 
    <para>
-      Both spinlocks and semaphores have read/write variants:
+      Both spinlocks and mutexes have read/write variants:
       <type>rwlock_t</type> and <structname>struct rw_semaphore</structname>.
       These divide users into two classes: the readers and the writers.  If
       you are only reading the data, you can get a read lock, but to write to
@@ -1681,7 +1672,7 @@ the amount of locking which needs to be done.
  #include &lt;linux/slab.h&gt;
  #include &lt;linux/string.h&gt;
 +#include &lt;linux/rcupdate.h&gt;
- #include &lt;linux/semaphore.h&gt;
+ #include &lt;linux/mutex.h&gt;
  #include &lt;asm/errno.h&gt;
 
  struct object
@@ -1913,7 +1904,7 @@ machines due to caching.
        </listitem>
        <listitem>
         <para>
-          <function> put_user()</function>
+          <function>put_user()</function>
         </para>
        </listitem>
       </itemizedlist>
@@ -1927,13 +1918,13 @@ machines due to caching.
 
      <listitem>
       <para>
-      <function>down_interruptible()</function> and
-      <function>down()</function>
+      <function>mutex_lock_interruptible()</function> and
+      <function>mutex_lock()</function>
       </para>
       <para>
-       There is a <function>down_trylock()</function> which can be
+       There is a <function>mutex_trylock()</function> which can be
        used inside interrupt context, as it will not sleep.
-       <function>up()</function> will also never sleep.
+       <function>mutex_unlock()</function> will also never sleep.
       </para>
      </listitem>
     </itemizedlist>
@@ -2023,7 +2014,7 @@ machines due to caching.
       <para>
         Prior to 2.5, or when <symbol>CONFIG_PREEMPT</symbol> is
         unset, processes in user context inside the kernel would not
-        preempt each other (ie. you had that CPU until you have it up,
+        preempt each other (ie. you had that CPU until you gave it up,
         except for interrupts).  With the addition of
         <symbol>CONFIG_PREEMPT</symbol> in 2.5.4, this changed: when
         in user context, higher priority tasks can "cut in": spinlocks

Documentation/DocBook/kgdb.tmpl

@@ -98,6 +98,24 @@
     "Kernel debugging" select "KGDB: kernel debugging with remote gdb".
     </para>
     <para>
+    It is advised, but not required that you turn on the
+    CONFIG_FRAME_POINTER kernel option.  This option inserts code to
+    into the compiled executable which saves the frame information in
+    registers or on the stack at different points which will allow a
+    debugger such as gdb to more accurately construct stack back traces
+    while debugging the kernel.
+    </para>
+    <para>
+    If the architecture that you are using supports the kernel option
+    CONFIG_DEBUG_RODATA, you should consider turning it off.  This
+    option will prevent the use of software breakpoints because it
+    marks certain regions of the kernel's memory space as read-only.
+    If kgdb supports it for the architecture you are using, you can
+    use hardware breakpoints if you desire to run with the
+    CONFIG_DEBUG_RODATA option turned on, else you need to turn off
+    this option.
+    </para>
+    <para>
     Next you should choose one of more I/O drivers to interconnect debugging
     host and debugged target.  Early boot debugging requires a KGDB
     I/O driver that supports early debugging and the driver must be

Documentation/DocBook/procfs-guide.tmpl

@@ -29,12 +29,12 @@
 
     <revhistory>
       <revision>
-	<revnumber>1.0&nbsp;</revnumber>
+	<revnumber>1.0</revnumber>
 	<date>May 30, 2001</date>
 	<revremark>Initial revision posted to linux-kernel</revremark>
       </revision>
       <revision>
-	<revnumber>1.1&nbsp;</revnumber>
+	<revnumber>1.1</revnumber>
 	<date>June 3, 2001</date>
 	<revremark>Revised after comments from linux-kernel</revremark>
       </revision>

Documentation/DocBook/s390-drivers.tmpl

@@ -100,7 +100,7 @@
       the hardware structures represented here, please consult the Principles
       of Operation.
     </para>
-!Iinclude/asm-s390/cio.h
+!Iarch/s390/include/asm/cio.h
     </sect1>
     <sect1 id="ccwdev">
      <title>ccw devices</title>
@@ -114,7 +114,7 @@
       ccw device structure. Device drivers must not bypass those functions
       or strange side effects may happen.
     </para>
-!Iinclude/asm-s390/ccwdev.h
+!Iarch/s390/include/asm/ccwdev.h
 !Edrivers/s390/cio/device.c
 !Edrivers/s390/cio/device_ops.c
     </sect1>
@@ -125,7 +125,7 @@
 	measurement data which is made available by the channel subsystem
 	for each channel attached device.
   </para>
-!Iinclude/asm-s390/cmb.h
+!Iarch/s390/include/asm/cmb.h
 !Edrivers/s390/cio/cmf.c
     </sect1>
   </chapter>
@@ -142,7 +142,7 @@
   </para>
    <sect1 id="ccwgroupdevices">
     <title>ccw group devices</title>
-!Iinclude/asm-s390/ccwgroup.h
+!Iarch/s390/include/asm/ccwgroup.h
 !Edrivers/s390/cio/ccwgroup.c
    </sect1>
   </chapter>

Documentation/DocBook/sh.tmpl

+<?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="sh-drivers">
+ <bookinfo>
+  <title>SuperH Interfaces Guide</title>
+  
+  <authorgroup>
+   <author>
+    <firstname>Paul</firstname>
+    <surname>Mundt</surname>
+    <affiliation>
+     <address>
+      <email>lethal@linux-sh.org</email>
+     </address>
+    </affiliation>
+   </author>
+  </authorgroup>
+
+  <copyright>
+   <year>2008</year>
+   <holder>Paul Mundt</holder>
+  </copyright>
+  <copyright>
+   <year>2008</year>
+   <holder>Renesas Technology Corp.</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="mm">
+    <title>Memory Management</title>
+    <sect1 id="sh4">
+    <title>SH-4</title>
+      <sect2 id="sq">
+        <title>Store Queue API</title>
+!Earch/sh/kernel/cpu/sh4/sq.c
+      </sect2>
+    </sect1>
+    <sect1 id="sh5">
+      <title>SH-5</title>
+      <sect2 id="tlb">
+	<title>TLB Interfaces</title>
+!Iarch/sh/mm/tlb-sh5.c
+!Iarch/sh/include/asm/tlb_64.h
+      </sect2>
+    </sect1>
+  </chapter>
+  <chapter id="clk">
+    <title>Clock Framework Extensions</title>
+!Iarch/sh/include/asm/clock.h
+  </chapter>
+  <chapter id="mach">
+    <title>Machine Specific Interfaces</title>
+    <sect1 id="dreamcast">
+      <title>mach-dreamcast</title>
+!Iarch/sh/boards/mach-dreamcast/rtc.c
+    </sect1>
+    <sect1 id="x3proto">
+      <title>mach-x3proto</title>
+!Earch/sh/boards/mach-x3proto/ilsel.c
+    </sect1>
+  </chapter>
+  <chapter id="busses">
+    <title>Busses</title>
+    <sect1 id="superhyway">
+      <title>SuperHyway</title>
+!Edrivers/sh/superhyway/superhyway.c
+    </sect1>
+
+    <sect1 id="maple">
+      <title>Maple</title>
+!Edrivers/sh/maple/maple.c
+    </sect1>
+  </chapter>
+</book>

Documentation/DocBook/uio-howto.tmpl

@@ -21,6 +21,18 @@
     </affiliation>
 </author>
 
+<copyright>
+	<year>2006-2008</year>
+	<holder>Hans-Jürgen Koch.</holder>
+</copyright>
+
+<legalnotice>
+<para>
+This documentation is Free Software licensed under the terms of the
+GPL version 2.
+</para>
+</legalnotice>
+
 <pubdate>2006-12-11</pubdate>
 
 <abstract>
@@ -29,6 +41,12 @@
 </abstract>
 
 <revhistory>
+	<revision>
+	<revnumber>0.5</revnumber>
+	<date>2008-05-22</date>
+	<authorinitials>hjk</authorinitials>
+	<revremark>Added description of write() function.</revremark>
+	</revision>
 	<revision>
 	<revnumber>0.4</revnumber>
 	<date>2007-11-26</date>
@@ -57,20 +75,9 @@
 </bookinfo>
 
 <chapter id="aboutthisdoc">
-<?dbhtml filename="about.html"?>
+<?dbhtml filename="aboutthis.html"?>
 <title>About this document</title>
 
-<sect1 id="copyright">
-<?dbhtml filename="copyright.html"?>
-<title>Copyright and License</title>
-<para>
-      Copyright (c) 2006 by Hans-Jürgen Koch.</para>
-<para>
-This documentation is Free Software licensed under the terms of the
-GPL version 2.
-</para>
-</sect1>
-
 <sect1 id="translations">
 <?dbhtml filename="translations.html"?>
 <title>Translations</title>
@@ -189,6 +196,30 @@ interested in translating it, please email me
 	represents the total interrupt count. You can use this number
 	to figure out if you missed some interrupts.
 	</para>
+	<para>
+	For some hardware that has more than one interrupt source internally,
+	but not separate IRQ mask and status registers, there might be
+	situations where userspace cannot determine what the interrupt source
+	was if the kernel handler disables them by writing to the chip's IRQ
+	register. In such a case, the kernel has to disable the IRQ completely
+	to leave the chip's register untouched. Now the userspace part can
+	determine the cause of the interrupt, but it cannot re-enable
+	interrupts. Another cornercase is chips where re-enabling interrupts
+	is a read-modify-write operation to a combined IRQ status/acknowledge
+	register. This would be racy if a new interrupt occurred
+	simultaneously.
+	</para>
+	<para>
+	To address these problems, UIO also implements a write() function. It
+	is normally not used and can be ignored for hardware that has only a
+	single interrupt source or has separate IRQ mask and status registers.
+	If you need it, however, a write to <filename>/dev/uioX</filename>
+	will call the <function>irqcontrol()</function> function implemented
+	by the driver. You have to write a 32-bit value that is usually either
+	0 or 1 to disable or enable interrupts. If a driver does not implement
+	<function>irqcontrol()</function>, <function>write()</function> will
+	return with <varname>-ENOSYS</varname>.
+	</para>
 
 	<para>
 	To handle interrupts properly, your custom kernel module can
@@ -362,6 +393,14 @@ device is actually used.
 <function>open()</function>, you will probably also want a custom
 <function>release()</function> function.
 </para></listitem>
+
+<listitem><para>
+<varname>int (*irqcontrol)(struct uio_info *info, s32 irq_on)
+</varname>: Optional. If you need to be able to enable or disable
+interrupts from userspace by writing to <filename>/dev/uioX</filename>,
+you can implement this function. The parameter <varname>irq_on</varname>
+will be 0 to disable interrupts and 1 to enable them.
+</para></listitem>
 </itemizedlist>
 
 <para>

Documentation/HOWTO

@@ -358,7 +358,7 @@ Here is a list of some of the different kernel trees available:
     - pcmcia, Dominik Brodowski <linux@dominikbrodowski.net>
 	git.kernel.org:/pub/scm/linux/kernel/git/brodo/pcmcia-2.6.git
 
-    - SCSI, James Bottomley <James.Bottomley@SteelEye.com>
+    - SCSI, James Bottomley <James.Bottomley@hansenpartnership.com>
 	git.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6.git
 
     - x86, Ingo Molnar <mingo@elte.hu>

Documentation/Intel-IOMMU.txt

@@ -48,7 +48,7 @@ IOVA generation is pretty generic. We used the same technique as vmalloc()
 but these are not global address spaces, but separate for each domain.
 Different DMA engines may support different number of domains.
 
-We also allocate gaurd pages with each mapping, so we can attempt to catch
+We also allocate guard pages with each mapping, so we can attempt to catch
 any overflow that might happen.
 
 
@@ -112,4 +112,4 @@ TBD
 
 - For compatibility testing, could use unity map domain for all devices, just
   provide a 1-1 for all useful memory under a single domain for all devices.
-- API for paravirt ops for abstracting functionlity for VMM folks.
+- API for paravirt ops for abstracting functionality for VMM folks.

Documentation/RCU/NMI-RCU.txt

@@ -93,6 +93,9 @@ Since NMI handlers disable preemption, synchronize_sched() is guaranteed
 not to return until all ongoing NMI handlers exit.  It is therefore safe
 to free up the handler's data as soon as synchronize_sched() returns.
 
+Important note: for this to work, the architecture in question must
+invoke irq_enter() and irq_exit() on NMI entry and exit, respectively.
+
 
 Answer to Quick Quiz
 

Documentation/RCU/RTFP.txt

@@ -52,6 +52,10 @@ of each iteration.  Unfortunately, chaotic relaxation requires highly
 structured data, such as the matrices used in scientific programs, and
 is thus inapplicable to most data structures in operating-system kernels.
 
+In 1992, Henry (now Alexia) Massalin completed a dissertation advising
+parallel programmers to defer processing when feasible to simplify
+synchronization.  RCU makes extremely heavy use of this advice.
+
 In 1993, Jacobson [Jacobson93] verbally described what is perhaps the
 simplest deferred-free technique: simply waiting a fixed amount of time
 before freeing blocks awaiting deferred free.  Jacobson did not describe
@@ -138,6 +142,13 @@ blocking in read-side critical sections appeared [PaulEMcKenney2006c],
 Robert Olsson described an RCU-protected trie-hash combination
 [RobertOlsson2006a].
 
+2007 saw the journal version of the award-winning RCU paper from 2006
+[ThomasEHart2007a], as well as a paper demonstrating use of Promela
+and Spin to mechanically verify an optimization to Oleg Nesterov's
+QRCU [PaulEMcKenney2007QRCUspin], a design document describing
+preemptible RCU [PaulEMcKenney2007PreemptibleRCU], and the three-part
+LWN "What is RCU?" series [PaulEMcKenney2007WhatIsRCUFundamentally,
+PaulEMcKenney2008WhatIsRCUUsage, and PaulEMcKenney2008WhatIsRCUAPI].
 
 Bibtex Entries
 
@@ -202,6 +213,20 @@ Bibtex Entries
 ,Year="1991"
 }
 
+@phdthesis{HMassalinPhD
+,author="H. Massalin"
+,title="Synthesis: An Efficient Implementation of Fundamental Operating
+System Services"
+,school="Columbia University"
+,address="New York, NY"
+,year="1992"
+,annotation="
+	Mondo optimizing compiler.
+	Wait-free stuff.
+	Good advice: defer work to avoid synchronization.
+"
+}
+
 @unpublished{Jacobson93
 ,author="Van Jacobson"
 ,title="Avoid Read-Side Locking Via Delayed Free"
@@ -635,3 +660,86 @@ Revised:
 "
 }
 
+@unpublished{PaulEMcKenney2007PreemptibleRCU
+,Author="Paul E. McKenney"
+,Title="The design of preemptible read-copy-update"
+,month="October"
+,day="8"
+,year="2007"
+,note="Available:
+\url{http://lwn.net/Articles/253651/}
+[Viewed October 25, 2007]"
+,annotation="
+	LWN article describing the design of preemptible RCU.
+"
+}
+
+########################################################################
+#
+#	"What is RCU?" LWN series.
+#
+
+@unpublished{PaulEMcKenney2007WhatIsRCUFundamentally
+,Author="Paul E. McKenney and Jonathan Walpole"
+,Title="What is {RCU}, Fundamentally?"
+,month="December"
+,day="17"
+,year="2007"
+,note="Available:
+\url{http://lwn.net/Articles/262464/}
+[Viewed December 27, 2007]"
+,annotation="
+	Lays out the three basic components of RCU: (1) publish-subscribe,
+	(2) wait for pre-existing readers to complete, and (2) maintain
+	multiple versions.
+"
+}
+
+@unpublished{PaulEMcKenney2008WhatIsRCUUsage
+,Author="Paul E. McKenney"
+,Title="What is {RCU}? Part 2: Usage"
+,month="January"
+,day="4"
+,year="2008"
+,note="Available:
+\url{http://lwn.net/Articles/263130/}
+[Viewed January 4, 2008]"
+,annotation="
+	Lays out six uses of RCU:
+	1. RCU is a Reader-Writer Lock Replacement
+	2. RCU is a Restricted Reference-Counting Mechanism
+	3. RCU is a Bulk Reference-Counting Mechanism
+	4. RCU is a Poor Man's Garbage Collector
+	5. RCU is a Way of Providing Existence Guarantees
+	6. RCU is a Way of Waiting for Things to Finish 
+"
+}
+
+@unpublished{PaulEMcKenney2008WhatIsRCUAPI
+,Author="Paul E. McKenney"
+,Title="{RCU} part 3: the {RCU} {API}"
+,month="January"
+,day="17"
+,year="2008"
+,note="Available:
+\url{http://lwn.net/Articles/264090/}
+[Viewed January 10, 2008]"
+,annotation="
+	Gives an overview of the Linux-kernel RCU API and a brief annotated RCU
+	bibliography.
+"
+}
+
+@article{DinakarGuniguntala2008IBMSysJ
+,author="D. Guniguntala and P. E. McKenney and J. Triplett and J. Walpole"
+,title="The read-copy-update mechanism for supporting real-time applications on shared-memory multiprocessor systems with {Linux}"
+,Year="2008"
+,Month="April"
+,journal="IBM Systems Journal"
+,volume="47"
+,number="2"
+,pages="@@-@@"
+,annotation="
+	RCU, realtime RCU, sleepable RCU, performance.
+"
+}

Documentation/RCU/checklist.txt

@@ -13,10 +13,13 @@ over a rather long period of time, but improvements are always welcome!
 	detailed performance measurements show that RCU is nonetheless
 	the right tool for the job.
 
-	The other exception would be where performance is not an issue,
-	and RCU provides a simpler implementation.  An example of this
-	situation is the dynamic NMI code in the Linux 2.6 kernel,
-	at least on architectures where NMIs are rare.
+	Another exception is where performance is not an issue, and RCU
+	provides a simpler implementation.  An example of this situation
+	is the dynamic NMI code in the Linux 2.6 kernel, at least on
+	architectures where NMIs are rare.
+
+	Yet another exception is where the low real-time latency of RCU's
+	read-side primitives is critically important.
 
 1.	Does the update code have proper mutual exclusion?
 
@@ -39,9 +42,10 @@ over a rather long period of time, but improvements are always welcome!
 
 2.	Do the RCU read-side critical sections make proper use of
 	rcu_read_lock() and friends?  These primitives are needed
-	to suppress preemption (or bottom halves, in the case of
-	rcu_read_lock_bh()) in the read-side critical sections,
-	and are also an excellent aid to readability.
+	to prevent grace periods from ending prematurely, which
+	could result in data being unceremoniously freed out from
+	under your read-side code, which can greatly increase the
+	actuarial risk of your kernel.
 
 	As a rough rule of thumb, any dereference of an RCU-protected
 	pointer must be covered by rcu_read_lock() or rcu_read_lock_bh()
@@ -54,15 +58,30 @@ over a rather long period of time, but improvements are always welcome!
 	be running while updates are in progress.  There are a number
 	of ways to handle this concurrency, depending on the situation:
 
-	a.	Make updates appear atomic to readers.  For example,
+	a.	Use the RCU variants of the list and hlist update
+		primitives to add, remove, and replace elements on an
+		RCU-protected list.  Alternatively, use the RCU-protected
+		trees that have been added to the Linux kernel.
+
+		This is almost always the best approach.
+
+	b.	Proceed as in (a) above, but also maintain per-element
+		locks (that are acquired by both readers and writers)
+		that guard per-element state.  Of course, fields that
+		the readers refrain from accessing can be guarded by the
+		update-side lock.
+
+		This works quite well, also.
+
+	c.	Make updates appear atomic to readers.  For example,
 		pointer updates to properly aligned fields will appear
 		atomic, as will individual atomic primitives.  Operations
 		performed under a lock and sequences of multiple atomic
 		primitives will -not- appear to be atomic.
 
-		This is almost always the best approach.
+		This can work, but is starting to get a bit tricky.
 
-	b.	Carefully order the updates and the reads so that
+	d.	Carefully order the updates and the reads so that
 		readers see valid data at all phases of the update.
 		This is often more difficult than it sounds, especially
 		given modern CPUs' tendency to reorder memory references.
@@ -123,18 +142,22 @@ over a rather long period of time, but improvements are always welcome!
 		when publicizing a pointer to a structure that can
 		be traversed by an RCU read-side critical section.
 
-5.	If call_rcu(), or a related primitive such as call_rcu_bh(),
-	is used, the callback function must be written to be called
-	from softirq context.  In particular, it cannot block.
+5.	If call_rcu(), or a related primitive such as call_rcu_bh() or
+	call_rcu_sched(), is used, the callback function must be
+	written to be called from softirq context.  In particular,
+	it cannot block.
 
 6.	Since synchronize_rcu() can block, it cannot be called from
-	any sort of irq context.
+	any sort of irq context.  Ditto for synchronize_sched() and
+	synchronize_srcu().
 
 7.	If the updater uses call_rcu(), then the corresponding readers
 	must use rcu_read_lock() and rcu_read_unlock().  If the updater
 	uses call_rcu_bh(), then the corresponding readers must use
-	rcu_read_lock_bh() and rcu_read_unlock_bh().  Mixing things up
-	will result in confusion and broken kernels.
+	rcu_read_lock_bh() and rcu_read_unlock_bh().  If the updater
+	uses call_rcu_sched(), then the corresponding readers must
+	disable preemption.  Mixing things up will result in confusion
+	and broken kernels.
 
 	One exception to this rule: rcu_read_lock() and rcu_read_unlock()
 	may be substituted for rcu_read_lock_bh() and rcu_read_unlock_bh()
@@ -143,9 +166,9 @@ over a rather long period of time, but improvements are always welcome!
 	such cases is a must, of course!  And the jury is still out on
 	whether the increased speed is worth it.
 
-8.	Although synchronize_rcu() is a bit slower than is call_rcu(),
-	it usually results in simpler code.  So, unless update
-	performance is critically important or the updaters cannot block,
+8.	Although synchronize_rcu() is slower than is call_rcu(), it
+	usually results in simpler code.  So, unless update performance
+	is critically important or the updaters cannot block,
 	synchronize_rcu() should be used in preference to call_rcu().
 
 	An especially important property of the synchronize_rcu()
@@ -187,23 +210,23 @@ over a rather long period of time, but improvements are always welcome!
 		number of updates per grace period.
 
 9.	All RCU list-traversal primitives, which include
-	list_for_each_rcu(), list_for_each_entry_rcu(),
+	rcu_dereference(), list_for_each_rcu(), list_for_each_entry_rcu(),
 	list_for_each_continue_rcu(), and list_for_each_safe_rcu(),
-	must be within an RCU read-side critical section.  RCU
+	must be either within an RCU read-side critical section or
+	must be protected by appropriate update-side locks.  RCU
 	read-side critical sections are delimited by rcu_read_lock()
 	and rcu_read_unlock(), or by similar primitives such as
 	rcu_read_lock_bh() and rcu_read_unlock_bh().
 
-	Use of the _rcu() list-traversal primitives outside of an
-	RCU read-side critical section causes no harm other than
-	a slight performance degradation on Alpha CPUs.  It can
-	also be quite helpful in reducing code bloat when common
-	code is shared between readers and updaters.
+	The reason that it is permissible to use RCU list-traversal
+	primitives when the update-side lock is held is that doing so
+	can be quite helpful in reducing code bloat when common code is
+	shared between readers and updaters.
 
 10.	Conversely, if you are in an RCU read-side critical section,
-	you -must- use the "_rcu()" variants of the list macros.
-	Failing to do so will break Alpha and confuse people reading
-	your code.
+	and you don't hold the appropriate update-side lock, you -must-
+	use the "_rcu()" variants of the list macros.  Failing to do so
+	will break Alpha and confuse people reading your code.
 
 11.	Note that synchronize_rcu() -only- guarantees to wait until
 	all currently executing rcu_read_lock()-protected RCU read-side
@@ -230,6 +253,14 @@ over a rather long period of time, but improvements are always welcome!
 	must use whatever locking or other synchronization is required
 	to safely access and/or modify that data structure.
 
+	RCU callbacks are -usually- executed on the same CPU that executed
+	the corresponding call_rcu(), call_rcu_bh(), or call_rcu_sched(),
+	but are by -no- means guaranteed to be.  For example, if a given
+	CPU goes offline while having an RCU callback pending, then that
+	RCU callback will execute on some surviving CPU.  (If this was
+	not the case, a self-spawning RCU callback would prevent the
+	victim CPU from ever going offline.)
+
 14.	SRCU (srcu_read_lock(), srcu_read_unlock(), and synchronize_srcu())
 	may only be invoked from process context.  Unlike other forms of
 	RCU, it -is- permissible to block in an SRCU read-side critical

Documentation/RCU/torture.txt

@@ -10,23 +10,30 @@ status messages via printk(), which can be examined via the dmesg
 command (perhaps grepping for "torture").  The test is started
 when the module is loaded, and stops when the module is unloaded.
 
-However, actually setting this config option to "y" results in the system
-running the test immediately upon boot, and ending only when the system
-is taken down.  Normally, one will instead want to build the system
-with CONFIG_RCU_TORTURE_TEST=m and to use modprobe and rmmod to control
-the test, perhaps using a script similar to the one shown at the end of
-this document.  Note that you will need CONFIG_MODULE_UNLOAD in order
-to be able to end the test.
+CONFIG_RCU_TORTURE_TEST_RUNNABLE
+
+It is also possible to specify CONFIG_RCU_TORTURE_TEST=y, which will
+result in the tests being loaded into the base kernel.  In this case,
+the CONFIG_RCU_TORTURE_TEST_RUNNABLE config option is used to specify
+whether the RCU torture tests are to be started immediately during
+boot or whether the /proc/sys/kernel/rcutorture_runnable file is used
+to enable them.  This /proc file can be used to repeatedly pause and
+restart the tests, regardless of the initial state specified by the
+CONFIG_RCU_TORTURE_TEST_RUNNABLE config option.
+
+You will normally -not- want to start the RCU torture tests during boot
+(and thus the default is CONFIG_RCU_TORTURE_TEST_RUNNABLE=n), but doing
+this can sometimes be useful in finding boot-time bugs.
 
 
 MODULE PARAMETERS
 
 This module has the following parameters:
 
-nreaders	This is the number of RCU reading threads supported.
-		The default is twice the number of CPUs.  Why twice?
-		To properly exercise RCU implementations with preemptible
-		read-side critical sections.
+irqreaders	Says to invoke RCU readers from irq level.  This is currently
+		done via timers.  Defaults to "1" for variants of RCU that
+		permit this.  (Or, more accurately, variants of RCU that do
+		-not- permit this know to ignore this variable.)
 
 nfakewriters	This is the number of RCU fake writer threads to run.  Fake
 		writer threads repeatedly use the synchronous "wait for
@@ -37,6 +44,16 @@ nfakewriters	This is the number of RCU fake writer threads to run.  Fake
 		to trigger special cases caused by multiple writers, such as
 		the synchronize_srcu() early return optimization.
 
+nreaders	This is the number of RCU reading threads supported.
+		The default is twice the number of CPUs.  Why twice?
+		To properly exercise RCU implementations with preemptible
+		read-side critical sections.
+
+shuffle_interval
+		The number of seconds to keep the test threads affinitied
+		to a particular subset of the CPUs, defaults to 3 seconds.
+		Used in conjunction with test_no_idle_hz.
+
 stat_interval	The number of seconds between output of torture
 		statistics (via printk()).  Regardless of the interval,
 		statistics are printed when the module is unloaded.
@@ -44,10 +61,11 @@ stat_interval	The number of seconds between output of torture
 		be printed -only- when the module is unloaded, and this
 		is the default.
 
-shuffle_interval
-		The number of seconds to keep the test threads affinitied
-		to a particular subset of the CPUs, defaults to 5 seconds.
-		Used in conjunction with test_no_idle_hz.
+stutter		The length of time to run the test before pausing for this
+		same period of time.  Defaults to "stutter=5", so as
+		to run and pause for (roughly) five-second intervals.
+		Specifying "stutter=0" causes the test to run continuously
+		without pausing, which is the old default behavior.
 
 test_no_idle_hz	Whether or not to test the ability of RCU to operate in
 		a kernel that disables the scheduling-clock interrupt to

Documentation/RCU/whatisRCU.txt

+Please note that the "What is RCU?" LWN series is an excellent place
+to start learning about RCU:
+
+1.	What is RCU, Fundamentally?  http://lwn.net/Articles/262464/
+2.	What is RCU? Part 2: Usage   http://lwn.net/Articles/263130/
+3.	RCU part 3: the RCU API      http://lwn.net/Articles/264090/
+
+
 What is RCU?
 
 RCU is a synchronization mechanism that was added to the Linux kernel
@@ -772,26 +780,18 @@ Linux-kernel source code, but it helps to have a full list of the
 APIs, since there does not appear to be a way to categorize them
 in docbook.  Here is the list, by category.
 
-Markers for RCU read-side critical sections:
-
-	rcu_read_lock
-	rcu_read_unlock
-	rcu_read_lock_bh
-	rcu_read_unlock_bh
-	srcu_read_lock
-	srcu_read_unlock
-
 RCU pointer/list traversal:
 
 	rcu_dereference
+	list_for_each_entry_rcu
+	hlist_for_each_entry_rcu
+
 	list_for_each_rcu		(to be deprecated in favor of
 					 list_for_each_entry_rcu)
-	list_for_each_entry_rcu
 	list_for_each_continue_rcu	(to be deprecated in favor of new
 					 list_for_each_entry_continue_rcu)
-	hlist_for_each_entry_rcu
 
-RCU pointer update:
+RCU pointer/list update:
 
 	rcu_assign_pointer
 	list_add_rcu
@@ -799,16 +799,36 @@ RCU pointer update:
 	list_del_rcu
 	list_replace_rcu
 	hlist_del_rcu
+	hlist_add_after_rcu
+	hlist_add_before_rcu
 	hlist_add_head_rcu
+	hlist_replace_rcu
+	list_splice_init_rcu()
 
-RCU grace period:
+RCU:	Critical sections	Grace period		Barrier
+
+	rcu_read_lock		synchronize_net		rcu_barrier
+	rcu_read_unlock		synchronize_rcu
+				call_rcu
+
+
+bh:	Critical sections	Grace period		Barrier
+
+	rcu_read_lock_bh	call_rcu_bh		rcu_barrier_bh
+	rcu_read_unlock_bh
+
+
+sched:	Critical sections	Grace period		Barrier
+
+	[preempt_disable]	synchronize_sched	rcu_barrier_sched
+	[and friends]		call_rcu_sched
+
+
+SRCU:	Critical sections	Grace period		Barrier
+
+	srcu_read_lock		synchronize_srcu	N/A
+	srcu_read_unlock
 
-	synchronize_net
-	synchronize_sched
-	synchronize_rcu
-	synchronize_srcu
-	call_rcu
-	call_rcu_bh
 
 See the comment headers in the source code (or the docbook generated
 from them) for more information.

Documentation/SubmittingPatches

@@ -528,7 +528,33 @@ See more details on the proper patch format in the following
 references.
 
 
+16) Sending "git pull" requests  (from Linus emails)
 
+Please write the git repo address and branch name alone on the same line
+so that I can't even by mistake pull from the wrong branch, and so
+that a triple-click just selects the whole thing.
+
+So the proper format is something along the lines of:
+
+	"Please pull from
+
+		git://jdelvare.pck.nerim.net/jdelvare-2.6 i2c-for-linus
+
+	 to get these changes:"
+
+so that I don't have to hunt-and-peck for the address and inevitably
+get it wrong (actually, I've only gotten it wrong a few times, and
+checking against the diffstat tells me when I get it wrong, but I'm
+just a lot more comfortable when I don't have to "look for" the right
+thing to pull, and double-check that I have the right branch-name).
+
+
+Please use "git diff -M --stat --summary" to generate the diffstat:
+the -M enables rename detection, and the summary enables a summary of
+new/deleted or renamed files.
+
+With rename detection, the statistics are rather different [...]
+because git will notice that a fair number of the changes are renames.
 
 -----------------------------------
 SECTION 2 - HINTS, TIPS, AND TRICKS

Documentation/accounting/delay-accounting.txt

@@ -11,6 +11,7 @@ the delays experienced by a task while
 a) waiting for a CPU (while being runnable)
 b) completion of synchronous block I/O initiated by the task
 c) swapping in pages
+d) memory reclaim
 
 and makes these statistics available to userspace through
 the taskstats interface.
@@ -41,7 +42,7 @@ this structure. See
      include/linux/taskstats.h
 for a description of the fields pertaining to delay accounting.
 It will generally be in the form of counters returning the cumulative
-delay seen for cpu, sync block I/O, swapin etc.
+delay seen for cpu, sync block I/O, swapin, memory reclaim etc.
 
 Taking the difference of two successive readings of a given
 counter (say cpu_delay_total) for a task will give the delay
@@ -94,7 +95,9 @@ CPU	count	real total	virtual total	delay total
 	7876	92005750	100000000	24001500
 IO	count	delay total
 	0	0
-MEM	count	delay total
+SWAP	count	delay total
+	0	0
+RECLAIM	count	delay total
 	0	0
 
 Get delays seen in executing a given simple command
@@ -108,5 +111,7 @@ CPU	count	real total	virtual total	delay total
 	6	4000250		4000000		0
 IO	count	delay total
 	0	0
-MEM	count	delay total
+SWAP	count	delay total
+	0	0
+RECLAIM	count	delay total
 	0	0

Documentation/accounting/getdelays.c

@@ -196,14 +196,18 @@ void print_delayacct(struct taskstats *t)
 	       "      %15llu%15llu%15llu%15llu\n"
 	       "IO    %15s%15s\n"
 	       "      %15llu%15llu\n"
-	       "MEM   %15s%15s\n"
+	       "SWAP  %15s%15s\n"
+	       "      %15llu%15llu\n"
+	       "RECLAIM  %12s%15s\n"
 	       "      %15llu%15llu\n",
 	       "count", "real total", "virtual total", "delay total",
 	       t->cpu_count, t->cpu_run_real_total, t->cpu_run_virtual_total,
 	       t->cpu_delay_total,
 	       "count", "delay total",
 	       t->blkio_count, t->blkio_delay_total,
-	       "count", "delay total", t->swapin_count, t->swapin_delay_total);
+	       "count", "delay total", t->swapin_count, t->swapin_delay_total,
+	       "count", "delay total",
+	       t->freepages_count, t->freepages_delay_total);
 }
 
 void task_context_switch_counts(struct taskstats *t)

Documentation/accounting/taskstats-struct.txt

@@ -6,7 +6,7 @@ This document contains an explanation of the struct taskstats fields.
 There are three different groups of fields in the struct taskstats:
 
 1) Common and basic accounting fields
-    If CONFIG_TASKSTATS is set, the taskstats inteface is enabled and
+    If CONFIG_TASKSTATS is set, the taskstats interface is enabled and
     the common fields and basic accounting fields are collected for
     delivery at do_exit() of a task.
 2) Delay accounting fields
@@ -26,6 +26,8 @@ There are three different groups of fields in the struct taskstats:
 
 5) Time accounting for SMT machines
 
+6) Extended delay accounting fields for memory reclaim
+
 Future extension should add fields to the end of the taskstats struct, and
 should not change the relative position of each field within the struct.
 
@@ -170,4 +172,9 @@ struct taskstats {
 	__u64	ac_utimescaled;		/* utime scaled on frequency etc */
 	__u64	ac_stimescaled;		/* stime scaled on frequency etc */
 	__u64	cpu_scaled_run_real_total; /* scaled cpu_run_real_total */
+
+6) Extended delay accounting fields for memory reclaim
+	/* Delay waiting for memory reclaim */
+	__u64	freepages_count;
+	__u64	freepages_delay_total;
 }

Documentation/arm/IXP4xx

@@ -32,7 +32,7 @@ Linux currently supports the following features on the IXP4xx chips:
 - Flash access (MTD/JFFS)
 - I2C through GPIO on IXP42x
 - GPIO for input/output/interrupts 
-  See include/asm-arm/arch-ixp4xx/platform.h for access functions.
+  See arch/arm/mach-ixp4xx/include/mach/platform.h for access functions.
 - Timers (watchdog, OS)
 
 The following components of the chips are not supported by Linux and

Documentation/arm/Interrupts

@@ -138,14 +138,8 @@ So, what's changed?
 
                 Set active the IRQ edge(s)/level.  This replaces the
                 SA1111 INTPOL manipulation, and the set_GPIO_IRQ_edge()
-                function.  Type should be one of the following:
-
-                #define IRQT_NOEDGE     (0)
-                #define IRQT_RISING     (__IRQT_RISEDGE)
-                #define IRQT_FALLING    (__IRQT_FALEDGE)
-                #define IRQT_BOTHEDGE   (__IRQT_RISEDGE|__IRQT_FALEDGE)
-                #define IRQT_LOW        (__IRQT_LOWLVL)
-                #define IRQT_HIGH       (__IRQT_HIGHLVL)
+                function.  Type should be one of IRQ_TYPE_xxx defined in
+		<linux/irq.h>
 
 3. set_GPIO_IRQ_edge() is obsolete, and should be replaced by set_irq_type.
 
@@ -164,7 +158,7 @@ So, what's changed?
    be re-checked for pending events.  (see the Neponset IRQ handler for
    details).
 
-7. fixup_irq() is gone, as is include/asm-arm/arch-*/irq.h
+7. fixup_irq() is gone, as is arch/arm/mach-*/include/mach/irq.h
 
 Please note that this will not solve all problems - some of them are
 hardware based.  Mixing level-based and edge-based IRQs on the same

Documentation/arm/README

@@ -79,7 +79,7 @@ Machine/Platform support
   To this end, we now have arch/arm/mach-$(MACHINE) directories which are
   designed to house the non-driver files for a particular machine (eg, PCI,
   memory management, architecture definitions etc).  For all future
-  machines, there should be a corresponding include/asm-arm/arch-$(MACHINE)
+  machines, there should be a corresponding arch/arm/mach-$(MACHINE)/include/mach
   directory.
 
 
@@ -176,7 +176,7 @@ Kernel entry (head.S)
   class typically based around one or more system on a chip devices, and
   acts as a natural container around the actual implementations.  These
   classes are given directories - arch/arm/mach-<class> and
-  include/asm-arm/arch-<class> - which contain the source files to
+  arch/arm/mach-<class> - which contain the source files to/include/mach
   support the machine class.  This directories also contain any machine
   specific supporting code.
 

Documentation/arm/Samsung-S3C24XX/GPIO.txt

@@ -16,13 +16,13 @@ Introduction
 Headers
 -------
 
-  See include/asm-arm/arch-s3c2410/regs-gpio.h for the list
+  See arch/arm/mach-s3c2410/include/mach/regs-gpio.h for the list
   of GPIO pins, and the configuration values for them. This
-  is included by using #include <asm/arch/regs-gpio.h>
+  is included by using #include <mach/regs-gpio.h>
 
   The GPIO management functions are defined in the hardware
-  header include/asm-arm/arch-s3c2410/hardware.h which can be
-  included by #include <asm/arch/hardware.h>
+  header arch/arm/mach-s3c2410/include/mach/hardware.h which can be
+  included by #include <mach/hardware.h>
 
   A useful amount of documentation can be found in the hardware
   header on how the GPIO functions (and others) work.

Documentation/arm/Samsung-S3C24XX/Overview.txt

@@ -36,7 +36,7 @@ Layout
   in arch/arm/mach-s3c2410 and S3C2440 in arch/arm/mach-s3c2440
 
   Register, kernel and platform data definitions are held in the
-  include/asm-arm/arch-s3c2410 directory.
+  arch/arm/mach-s3c2410 directory./include/mach
 
 
 Machines

Documentation/arm/Samsung-S3C24XX/USB-Host.txt

@@ -49,7 +49,7 @@ Board Support
 Platform Data
 -------------
 
-  See linux/include/asm-arm/arch-s3c2410/usb-control.h for the
+  See arch/arm/mach-s3c2410/include/mach/usb-control.h for the
   descriptions of the platform device data. An implementation
   can be found in linux/arch/arm/mach-s3c2410/usb-simtec.c .
 

Documentation/bt8xxgpio.txt

+===============================================================
+==  BT8XXGPIO driver                                         ==
+==                                                           ==
+==  A driver for a selfmade cheap BT8xx based PCI GPIO-card  ==
+==                                                           ==
+==  For advanced documentation, see                          ==
+==  http://www.bu3sch.de/btgpio.php                          ==
+===============================================================
+
+
+A generic digital 24-port PCI GPIO card can be built out of an ordinary
+Brooktree bt848, bt849, bt878 or bt879 based analog TV tuner card. The
+Brooktree chip is used in old analog Hauppauge WinTV PCI cards. You can easily
+find them used for low prices on the net.
+
+The bt8xx chip does have 24 digital GPIO ports.
+These ports are accessible via 24 pins on the SMD chip package.
+
+
+==============================================
+==  How to physically access the GPIO pins  ==
+==============================================
+
+The are several ways to access these pins. One might unsolder the whole chip
+and put it on a custom PCI board, or one might only unsolder each individual
+GPIO pin and solder that to some tiny wire. As the chip package really is tiny
+there are some advanced soldering skills needed in any case.
+
+The physical pinouts are drawn in the following ASCII art.
+The GPIO pins are marked with G00-G23
+
+                                           G G G G G G G G G G G G     G G G G G G
+                                           0 0 0 0 0 0 0 0 0 0 1 1     1 1 1 1 1 1
+                                           0 1 2 3 4 5 6 7 8 9 0 1     2 3 4 5 6 7
+           | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
+           ---------------------------------------------------------------------------
+         --|                               ^                                     ^   |--
+         --|                               pin 86                           pin 67   |--
+         --|                                                                         |--
+         --|                                                               pin 61 >  |-- G18
+         --|                                                                         |-- G19
+         --|                                                                         |-- G20
+         --|                                                                         |-- G21
+         --|                                                                         |-- G22
+         --|                                                               pin 56 >  |-- G23
+         --|                                                                         |--
+         --|                           Brooktree 878/879                             |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|                                                                         |--
+         --|   O                                                                     |--
+         --|                                                                         |--
+           ---------------------------------------------------------------------------
+           | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
+           ^
+           This is pin 1
+

Documentation/cli-sti-removal.txt

-
-#### cli()/sti() removal guide, started by Ingo Molnar <mingo@redhat.com>
-
-
-as of 2.5.28, five popular macros have been removed on SMP, and
-are being phased out on UP:
-
- cli(), sti(), save_flags(flags), save_flags_cli(flags), restore_flags(flags)
-
-until now it was possible to protect driver code against interrupt
-handlers via a cli(), but from now on other, more lightweight methods
-have to be used for synchronization, such as spinlocks or semaphores.
-
-for example, driver code that used to do something like:
-
-	struct driver_data;
-
-	irq_handler (...)
-	{
-		....
-		driver_data.finish = 1;
-		driver_data.new_work = 0;
-		....
-	}
-
-	...
-
-	ioctl_func (...)
-	{
-		...
-		cli();
-		...
-		driver_data.finish = 0;
-		driver_data.new_work = 2;
-		...
-		sti();
-		...
-	}
-
-was SMP-correct because the cli() function ensured that no
-interrupt handler (amongst them the above irq_handler()) function
-would execute while the cli()-ed section is executing.
-
-but from now on a more direct method of locking has to be used:
-
-	DEFINE_SPINLOCK(driver_lock);
-	struct driver_data;
-
-	irq_handler (...)
-	{
-		unsigned long flags;
-		....
-		spin_lock_irqsave(&driver_lock, flags);
-		....
-		driver_data.finish = 1;
-		driver_data.new_work = 0;
-		....
-		spin_unlock_irqrestore(&driver_lock, flags);
-		....
-	}
-
-	...
-
-	ioctl_func (...)
-	{
-		...
-		spin_lock_irq(&driver_lock);
-		...
-		driver_data.finish = 0;
-		driver_data.new_work = 2;
-		...
-		spin_unlock_irq(&driver_lock);
-		...
-	}
-
-the above code has a number of advantages:
-
-- the locking relation is easier to understand - actual lock usage
-  pinpoints the critical sections. cli() usage is too opaque.
-  Easier to understand means it's easier to debug.
-
-- it's faster, because spinlocks are faster to acquire than the
-  potentially heavily-used IRQ lock. Furthermore, your driver does
-  not have to wait eg. for a big heavy SCSI interrupt to finish,
-  because the driver_lock spinlock is only used by your driver.
-  cli() on the other hand was used by many drivers, and extended
-  the critical section to the whole IRQ handler function - creating
-  serious lock contention.
-
- 
-to make the transition easier, we've still kept the cli(), sti(),
-save_flags(), save_flags_cli() and restore_flags() macros defined
-on UP systems - but their usage will be phased out until 2.6 is
-released.
-
-drivers that want to disable local interrupts (interrupts on the
-current CPU), can use the following five macros:
-
-  local_irq_disable(), local_irq_enable(), local_save_flags(flags),
-  local_irq_save(flags), local_irq_restore(flags)
-
-but beware, their meaning and semantics are much simpler, far from
-that of the old cli(), sti(), save_flags(flags) and restore_flags(flags)
-SMP meaning:
-
-    local_irq_disable()       => turn local IRQs off
-
-    local_irq_enable()        => turn local IRQs on
-
-    local_save_flags(flags)   => save the current IRQ state into flags. The
-                                 state can be on or off. (on some
-                                 architectures there's even more bits in it.)
-
-    local_irq_save(flags)     => save the current IRQ state into flags and
-                                 disable interrupts.
-
-    local_irq_restore(flags)  => restore the IRQ state from flags.
-
-(local_irq_save can save both irqs on and irqs off state, and
-local_irq_restore can restore into both irqs on and irqs off state.)
-
-another related change is that synchronize_irq() now takes a parameter:
-synchronize_irq(irq). This change too has the purpose of making SMP
-synchronization more lightweight - this way you can wait for your own
-interrupt handler to finish, no need to wait for other IRQ sources.
-
-
-why were these changes done? The main reason was the architectural burden
-of maintaining the cli()/sti() interface - it became a real problem. The
-new interrupt system is much more streamlined, easier to understand, debug,
-and it's also a bit faster - the same happened to it that will happen to
-cli()/sti() using drivers once they convert to spinlocks :-)
-

Documentation/controllers/memory.txt

@@ -242,8 +242,7 @@ rmdir() if there are no tasks.
 1. Add support for accounting huge pages (as a separate controller)
 2. Make per-cgroup scanner reclaim not-shared pages first
 3. Teach controller to account for shared-pages
-4. Start reclamation when the limit is lowered
-5. Start reclamation in the background when the limit is
+4. Start reclamation in the background when the limit is
    not yet hit but the usage is getting closer
 
 Summary

Documentation/cpu-freq/governors.txt

@@ -122,7 +122,7 @@ around '10000' or more.
 show_sampling_rate_(min|max): the minimum and maximum sampling rates
 available that you may set 'sampling_rate' to.
 
-up_threshold: defines what the average CPU usaged between the samplings
+up_threshold: defines what the average CPU usage between the samplings
 of 'sampling_rate' needs to be for the kernel to make a decision on
 whether it should increase the frequency.  For example when it is set
 to its default value of '80' it means that between the checking

Documentation/edac.txt

@@ -222,74 +222,9 @@ both csrow2 and csrow3 are populated, this indicates a dual ranked
 set of DIMMs for channels 0 and 1.
 
 
-Within each of the 'mc','mcX' and 'csrowX' directories are several
+Within each of the 'mcX' and 'csrowX' directories are several
 EDAC control and attribute files.
 
-
-============================================================================
-DIRECTORY 'mc'
-
-In directory 'mc' are EDAC system overall control and attribute files:
-
-
-Panic on UE control file:
-
-	'edac_mc_panic_on_ue'
-
-	An uncorrectable error will cause a machine panic.  This is usually
-	desirable.  It is a bad idea to continue when an uncorrectable error
-	occurs - it is indeterminate what was uncorrected and the operating
-	system context might be so mangled that continuing will lead to further
-	corruption. If the kernel has MCE configured, then EDAC will never
-	notice the UE.
-
-	LOAD TIME: module/kernel parameter: panic_on_ue=[0|1]
-
-	RUN TIME:  echo "1" >/sys/devices/system/edac/mc/edac_mc_panic_on_ue
-
-
-Log UE control file:
-
-	'edac_mc_log_ue'
-
-	Generate kernel messages describing uncorrectable errors.  These errors
-	are reported through the system message log system.  UE statistics
-	will be accumulated even when UE logging is disabled.
-
-	LOAD TIME: module/kernel parameter: log_ue=[0|1]
-
-	RUN TIME: echo "1" >/sys/devices/system/edac/mc/edac_mc_log_ue
-
-
-Log CE control file:
-
-	'edac_mc_log_ce'
-
-	Generate kernel messages describing correctable errors.  These
-	errors are reported through the system message log system.
-	CE statistics will be accumulated even when CE logging is disabled.
-
-	LOAD TIME: module/kernel parameter: log_ce=[0|1]
-
-	RUN TIME: echo "1" >/sys/devices/system/edac/mc/edac_mc_log_ce
-
-
-Polling period control file:
-
-	'edac_mc_poll_msec'
-
-	The time period, in milliseconds, for polling for error information.
-	Too small a value wastes resources.  Too large a value might delay
-	necessary handling of errors and might loose valuable information for
-	locating the error.  1000 milliseconds (once each second) is the current
-	default. Systems which require all the bandwidth they can get, may
-	increase this.
-
-	LOAD TIME: module/kernel parameter: poll_msec=[0|1]
-
-	RUN TIME: echo "1000" >/sys/devices/system/edac/mc/edac_mc_poll_msec
-
-
 ============================================================================
 'mcX' DIRECTORIES
 
@@ -392,7 +327,7 @@ Sdram memory scrubbing rate:
 	'sdram_scrub_rate'
 
 	Read/Write attribute file that controls memory scrubbing. The scrubbing
-	rate is set by writing a minimum bandwith in bytes/sec to the attribute
+	rate is set by writing a minimum bandwidth in bytes/sec to the attribute
 	file. The rate will be translated to an internal value that gives at
 	least the specified rate.
 
@@ -537,7 +472,6 @@ Channel 1 DIMM Label control file:
 	motherboard specific and determination of this information
 	must occur in userland at this time.
 
-
 ============================================================================
 SYSTEM LOGGING
 
@@ -570,7 +504,6 @@ error type, a notice of "no info" and then an optional,
 driver-specific error message.
 
 
-
 ============================================================================
 PCI Bus Parity Detection
 
@@ -604,6 +537,74 @@ Enable/Disable PCI Parity checking control file:
 	echo "0" >/sys/devices/system/edac/pci/check_pci_parity
 
 
+Parity Count:
+
+	'pci_parity_count'
+
+	This attribute file will display the number of parity errors that
+	have been detected.
+
+
+============================================================================
+MODULE PARAMETERS
+
+Panic on UE control file:
+
+	'edac_mc_panic_on_ue'
+
+	An uncorrectable error will cause a machine panic.  This is usually
+	desirable.  It is a bad idea to continue when an uncorrectable error
+	occurs - it is indeterminate what was uncorrected and the operating
+	system context might be so mangled that continuing will lead to further
+	corruption. If the kernel has MCE configured, then EDAC will never
+	notice the UE.
+
+	LOAD TIME: module/kernel parameter: edac_mc_panic_on_ue=[0|1]
+
+	RUN TIME:  echo "1" > /sys/module/edac_core/parameters/edac_mc_panic_on_ue
+
+
+Log UE control file:
+
+	'edac_mc_log_ue'
+
+	Generate kernel messages describing uncorrectable errors.  These errors
+	are reported through the system message log system.  UE statistics
+	will be accumulated even when UE logging is disabled.
+
+	LOAD TIME: module/kernel parameter: edac_mc_log_ue=[0|1]
+
+	RUN TIME: echo "1" > /sys/module/edac_core/parameters/edac_mc_log_ue
+
+
+Log CE control file:
+
+	'edac_mc_log_ce'
+
+	Generate kernel messages describing correctable errors.  These
+	errors are reported through the system message log system.
+	CE statistics will be accumulated even when CE logging is disabled.
+
+	LOAD TIME: module/kernel parameter: edac_mc_log_ce=[0|1]
+
+	RUN TIME: echo "1" > /sys/module/edac_core/parameters/edac_mc_log_ce
+
+
+Polling period control file:
+
+	'edac_mc_poll_msec'
+
+	The time period, in milliseconds, for polling for error information.
+	Too small a value wastes resources.  Too large a value might delay
+	necessary handling of errors and might loose valuable information for
+	locating the error.  1000 milliseconds (once each second) is the current
+	default. Systems which require all the bandwidth they can get, may
+	increase this.
+
+	LOAD TIME: module/kernel parameter: edac_mc_poll_msec=[0|1]
+
+	RUN TIME: echo "1000" > /sys/module/edac_core/parameters/edac_mc_poll_msec
+
 
 Panic on PCI PARITY Error:
 
@@ -614,21 +615,13 @@ Panic on PCI PARITY Error:
 	error has been detected.
 
 
-	module/kernel parameter: panic_on_pci_parity=[0|1]
+	module/kernel parameter: edac_panic_on_pci_pe=[0|1]
 
 	Enable:
-	echo "1" >/sys/devices/system/edac/pci/panic_on_pci_parity
+	echo "1" > /sys/module/edac_core/parameters/edac_panic_on_pci_pe
 
 	Disable:
-	echo "0" >/sys/devices/system/edac/pci/panic_on_pci_parity
-
-
-Parity Count:
-
-	'pci_parity_count'
-
-	This attribute file will display the number of parity errors that
-	have been detected.
+	echo "0" > /sys/module/edac_core/parameters/edac_panic_on_pci_pe
 
 
 

Documentation/fb/sh7760fb.txt

+SH7760/SH7763 integrated LCDC Framebuffer driver
+================================================
+
+0. Overwiew
+-----------
+The SH7760/SH7763 have an integrated LCD Display controller (LCDC) which
+supports (in theory) resolutions ranging from 1x1 to 1024x1024,
+with color depths ranging from 1 to 16 bits, on STN, DSTN and TFT Panels.
+
+Caveats:
+* Framebuffer memory must be a large chunk allocated at the top
+  of Area3 (HW requirement). Because of this requirement you should NOT
+  make the driver a module since at runtime it may become impossible to
+  get a large enough contiguous chunk of memory.
+
+* The driver does not support changing resolution while loaded
+  (displays aren't hotpluggable anyway)
+
+* Heavy flickering may be observed
+  a) if you're using 15/16bit color modes at >= 640x480 px resolutions,
+  b) during PCMCIA (or any other slow bus) activity.
+
+* Rotation works only 90degress clockwise, and only if horizontal
+  resolution is <= 320 pixels.
+
+files:   drivers/video/sh7760fb.c
+        include/asm-sh/sh7760fb.h
+        Documentation/fb/sh7760fb.txt
+
+1. Platform setup
+-----------------
+SH7760:
+ Video data is fetched via the DMABRG DMA engine, so you have to
+ configure the SH DMAC for DMABRG mode (write 0x94808080 to the
+ DMARSRA register somewhere at boot).
+
+ PFC registers PCCR and PCDR must be set to peripheral mode.
+ (write zeros to both).
+
+The driver does NOT do the above for you since board setup is, well, job
+of the board setup code.
+
+2. Panel definitions
+--------------------
+The LCDC must explicitly be told about the type of LCD panel
+attached.  Data must be wrapped in a "struct sh7760fb_platdata" and
+passed to the driver as platform_data.
+
+Suggest you take a closer look at the SH7760 Manual, Section 30.
+(http://documentation.renesas.com/eng/products/mpumcu/e602291_sh7760.pdf)
+
+The following code illustrates what needs to be done to
+get the framebuffer working on a 640x480 TFT:
+
+====================== cut here ======================================
+
+#include <linux/fb.h>
+#include <asm/sh7760fb.h>
+
+/*
+ * NEC NL6440bc26-01 640x480 TFT
+ * dotclock 25175 kHz
+ * Xres                640     Yres            480
+ * Htotal      800     Vtotal          525
+ * HsynStart   656     VsynStart       490
+ * HsynLenn    30      VsynLenn        2
+ *
+ * The linux framebuffer layer does not use the syncstart/synclen
+ * values but right/left/upper/lower margin values. The comments
+ * for the x_margin explain how to calculate those from given
+ * panel sync timings.
+ */
+static struct fb_videomode nl6448bc26 = {
+       .name           = "NL6448BC26",
+       .refresh        = 60,
+       .xres           = 640,
+       .yres           = 480,
+       .pixclock       = 39683,        /* in picoseconds! */
+       .hsync_len      = 30,
+       .vsync_len      = 2,
+       .left_margin    = 114,  /* HTOT - (HSYNSLEN + HSYNSTART) */
+       .right_margin   = 16,   /* HSYNSTART - XRES */
+       .upper_margin   = 33,   /* VTOT - (VSYNLEN + VSYNSTART) */
+       .lower_margin   = 10,   /* VSYNSTART - YRES */
+       .sync           = FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
+       .vmode          = FB_VMODE_NONINTERLACED,
+       .flag           = 0,
+};
+
+static struct sh7760fb_platdata sh7760fb_nl6448 = {
+       .def_mode       = &nl6448bc26,
+       .ldmtr          = LDMTR_TFT_COLOR_16,   /* 16bit TFT panel */
+       .lddfr          = LDDFR_8BPP,           /* we want 8bit output */
+       .ldpmmr         = 0x0070,
+       .ldpspr         = 0x0500,
+       .ldaclnr        = 0,
+       .ldickr         = LDICKR_CLKSRC(LCDC_CLKSRC_EXTERNAL) |
+                         LDICKR_CLKDIV(1),
+       .rotate         = 0,
+       .novsync        = 1,
+       .blank          = NULL,
+};
+
+/* SH7760:
+ * 0xFE300800: 256 * 4byte xRGB palette ram
+ * 0xFE300C00: 42 bytes ctrl registers
+ */
+static struct resource sh7760_lcdc_res[] = {
+       [0] = {
+               .start  = 0xFE300800,
+               .end    = 0xFE300CFF,
+               .flags  = IORESOURCE_MEM,
+       },
+       [1] = {
+               .start  = 65,
+               .end    = 65,
+               .flags  = IORESOURCE_IRQ,
+       },
+};
+
+static struct platform_device sh7760_lcdc_dev = {
+       .dev    = {
+               .platform_data = &sh7760fb_nl6448,
+       },
+       .name           = "sh7760-lcdc",
+       .id             = -1,
+       .resource       = sh7760_lcdc_res,
+       .num_resources  = ARRAY_SIZE(sh7760_lcdc_res),
+};
+
+====================== cut here ======================================

Documentation/fb/tridentfb.txt

@@ -3,11 +3,25 @@ Tridentfb is a framebuffer driver for some Trident chip based cards.
 The following list of chips is thought to be supported although not all are
 tested:
 
-those from the Image series with Cyber in their names - accelerated
-those with Blade in their names (Blade3D,CyberBlade...) - accelerated
-the newer CyberBladeXP family  - nonaccelerated
-
-Only PCI/AGP based cards are supported, none of the older Tridents.
+those from the TGUI series 9440/96XX and with Cyber in their names
+those from the Image series and with Cyber in their names
+those with Blade in their names (Blade3D,CyberBlade...)
+the newer CyberBladeXP family
+
+All families are accelerated. Only PCI/AGP based cards are supported,
+none of the older Tridents.
+The driver supports 8, 16 and 32 bits per pixel depths.
+The TGUI family requires a line length to be power of 2 if acceleration
+is enabled. This means that range of possible resolutions and bpp is
+limited comparing to the range if acceleration is disabled (see list
+of parameters below).
+
+Known bugs:
+1. The driver randomly locks up on 3DImage975 chip with acceleration
+   enabled. The same happens in X11 (Xorg).
+2. The ramdac speeds require some more fine tuning. It is possible to
+   switch resolution which the chip does not support at some depths for
+   older chips.
 
 How to use it?
 ==============
@@ -17,12 +31,11 @@ video=tridentfb
 
 The parameters for tridentfb are concatenated with a ':' as in this example.
 
-video=tridentfb:800x600,bpp=16,noaccel
+video=tridentfb:800x600-16@75,noaccel
 
 The second level parameters that tridentfb understands are:
 
 noaccel - turns off acceleration (when it doesn't work for your card)
-accel - force text acceleration (for boards which by default are noacceled)
 
 fp	- use flat panel related stuff
 crt 	- assume monitor is present instead of fp
@@ -31,21 +44,24 @@ center 	- for flat panels and resolutions smaller than native size center the
 	  image, otherwise use
 stretch
 
-memsize - integer value in Kb, use if your card's memory size is misdetected.
+memsize - integer value in KB, use if your card's memory size is misdetected.
 	  look at the driver output to see what it says when initializing.
-memdiff - integer value in Kb,should be nonzero if your card reports
-	  more memory than it actually has.For instance mine is 192K less than
+
+memdiff - integer value in KB, should be nonzero if your card reports
+	  more memory than it actually has. For instance mine is 192K less than
 	  detection says in all three BIOS selectable situations 2M, 4M, 8M.
 	  Only use if your video memory is taken from main memory hence of
-	  configurable size.Otherwise use memsize.
-	  If in some modes which barely fit the memory you see garbage at the bottom
-	  this might help by not letting change to that mode anymore.
+	  configurable size. Otherwise use memsize.
+	  If in some modes which barely fit the memory you see garbage
+	  at the bottom this might help by not letting change to that mode
+	  anymore.
 
 nativex - the width in pixels of the flat panel.If you know it (usually 1024
 	  800 or 1280) and it is not what the driver seems to detect use it.
 
-bpp  - bits per pixel (8,16 or 32)
-mode - a mode name like 800x600 (as described in Documentation/fb/modedb.txt)
+bpp	- bits per pixel (8,16 or 32)
+mode	- a mode name like 800x600-8@75 as described in
+	  Documentation/fb/modedb.txt
 
 Using insane values for the above parameters will probably result in driver
 misbehaviour so take care(for instance memsize=12345678 or memdiff=23784 or

Documentation/feature-removal-schedule.txt

@@ -47,6 +47,30 @@ Who:	Mauro Carvalho Chehab <mchehab@infradead.org>
 
 ---------------------------
 
+What:	old tuner-3036 i2c driver
+When:	2.6.28
+Why:	This driver is for VERY old i2c-over-parallel port teletext receiver
+	boxes. Rather then spending effort on converting this driver to V4L2,
+	and since it is extremely unlikely that anyone still uses one of these
+	devices, it was decided to drop it.
+Who:	Hans Verkuil <hverkuil@xs4all.nl>
+	Mauro Carvalho Chehab <mchehab@infradead.org>
+
+ ---------------------------
+
+What:   V4L2 dpc7146 driver
+When:   2.6.28
+Why:    Old driver for the dpc7146 demonstration board that is no longer
+	relevant. The last time this was tested on actual hardware was
+	probably around 2002. Since this is a driver for a demonstration
+	board the decision was made to remove it rather than spending a
+	lot of effort continually updating this driver to stay in sync
+	with the latest internal V4L2 or I2C API.
+Who:    Hans Verkuil <hverkuil@xs4all.nl>
+	Mauro Carvalho Chehab <mchehab@infradead.org>
+
+---------------------------
+
 What:	PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl])
 When:	November 2005
 Files:	drivers/pcmcia/: pcmcia_ioctl.c
@@ -138,24 +162,6 @@ Who:	Kay Sievers <kay.sievers@suse.de>
 
 ---------------------------
 
-What:	find_task_by_pid
-When:	2.6.26
-Why:	With pid namespaces, calling this funciton will return the
-	wrong task when called from inside a namespace.
-
-	The best way to save a task pid and find a task by this
-	pid later, is to find this task's struct pid pointer (or get
-	it directly from the task) and call pid_task() later.
-
-	If someone really needs to get a task by its pid_t, then
-	he most likely needs the find_task_by_vpid() to get the
-	task from the same namespace as the current task is in, but
-	this may be not so in general.
-
-Who:	Pavel Emelyanov <xemul@openvz.org>
-
----------------------------
-
 What:	ACPI procfs interface
 When:	July 2008
 Why:	ACPI sysfs conversion should be finished by January 2008.
@@ -300,11 +306,15 @@ Who:	ocfs2-devel@oss.oracle.com
 
 ---------------------------
 
-What:	asm/semaphore.h
-When:	2.6.26
-Why:	Implementation became generic; users should now include
-	linux/semaphore.h instead.
-Who:	Matthew Wilcox <willy@linux.intel.com>
+What:	SCTP_GET_PEER_ADDRS_NUM_OLD, SCTP_GET_PEER_ADDRS_OLD,
+	SCTP_GET_LOCAL_ADDRS_NUM_OLD, SCTP_GET_LOCAL_ADDRS_OLD
+When: 	June 2009
+Why:    A newer version of the options have been introduced in 2005 that
+	removes the limitions of the old API.  The sctp library has been
+        converted to use these new options at the same time.  Any user
+	space app that directly uses the old options should convert to using
+	the new options.
+Who:	Vlad Yasevich <vladislav.yasevich@hp.com>
 
 ---------------------------
 
@@ -314,3 +324,23 @@ Why:	This option was introduced just to allow older lm-sensors userspace
 	to keep working over the upgrade to 2.6.26. At the scheduled time of
 	removal fixed lm-sensors (2.x or 3.x) should be readily available.
 Who:	Rene Herman <rene.herman@gmail.com>
+
+---------------------------
+
+What:	Code that is now under CONFIG_WIRELESS_EXT_SYSFS
+	(in net/core/net-sysfs.c)
+When:	After the only user (hal) has seen a release with the patches
+	for enough time, probably some time in 2010.
+Why:	Over 1K .text/.data size reduction, data is available in other
+	ways (ioctls)
+Who:	Johannes Berg <johannes@sipsolutions.net>
+
+---------------------------
+
+What: CONFIG_NF_CT_ACCT
+When: 2.6.29
+Why:  Accounting can now be enabled/disabled without kernel recompilation.
+      Currently used only to set a default value for a feature that is also
+      controlled by a kernel/module/sysfs/sysctl parameter.
+Who:  Krzysztof Piotr Oledzki <ole@ans.pl>
+

Documentation/filesystems/Locking

@@ -510,6 +510,7 @@ prototypes:
 	void (*close)(struct vm_area_struct*);
 	int (*fault)(struct vm_area_struct*, struct vm_fault *);
 	int (*page_mkwrite)(struct vm_area_struct *, struct page *);
+	int (*access)(struct vm_area_struct *, unsigned long, void*, int, int);
 
 locking rules:
 		BKL	mmap_sem	PageLocked(page)
@@ -517,6 +518,7 @@ open:		no	yes
 close:		no	yes
 fault:		no	yes
 page_mkwrite:	no	yes		no
+access:		no	yes
 
 	->page_mkwrite() is called when a previously read-only page is
 about to become writeable. The file system is responsible for
@@ -525,6 +527,11 @@ taking to lock out truncate, the page range should be verified to be
 within i_size. The page mapping should also be checked that it is not
 NULL.
 
+	->access() is called when get_user_pages() fails in
+acces_process_vm(), typically used to debug a process through
+/proc/pid/mem or ptrace.  This function is needed only for
+VM_IO | VM_PFNMAP VMAs.
+
 ================================================================================
 			Dubious stuff
 

Documentation/filesystems/bfs.txt

@@ -26,11 +26,11 @@ You can simplify mounting by just typing:
 
 this will allocate the first available loopback device (and load loop.o 
 kernel module if necessary) automatically. If the loopback driver is not
-loaded automatically, make sure that your kernel is compiled with kmod 
-support (CONFIG_KMOD) enabled. Beware that umount will not
-deallocate /dev/loopN device if /etc/mtab file on your system is a
-symbolic link to /proc/mounts. You will need to do it manually using
-"-d" switch of losetup(8). Read losetup(8) manpage for more info.
+loaded automatically, make sure that you have compiled the module and
+that modprobe is functioning. Beware that umount will not deallocate
+/dev/loopN device if /etc/mtab file on your system is a symbolic link to
+/proc/mounts. You will need to do it manually using "-d" switch of
+losetup(8). Read losetup(8) manpage for more info.
 
 To create the BFS image under UnixWare you need to find out first which
 slice contains it. The command prtvtoc(1M) is your friend:

Documentation/filesystems/configfs/configfs.txt

@@ -311,9 +311,20 @@ the subsystem must be ready for it.
 [An Example]
 
 The best example of these basic concepts is the simple_children
-subsystem/group and the simple_child item in configfs_example.c  It
-shows a trivial object displaying and storing an attribute, and a simple
-group creating and destroying these children.
+subsystem/group and the simple_child item in configfs_example_explicit.c
+and configfs_example_macros.c.  It shows a trivial object displaying and
+storing an attribute, and a simple group creating and destroying these
+children.
+
+The only difference between configfs_example_explicit.c and
+configfs_example_macros.c is how the attributes of the childless item
+are defined.  The childless item has extended attributes, each with
+their own show()/store() operation.  This follows a convention commonly
+used in sysfs.  configfs_example_explicit.c creates these attributes
+by explicitly defining the structures involved.  Conversely
+configfs_example_macros.c uses some convenience macros from configfs.h
+to define the attributes.  These macros are similar to their sysfs
+counterparts.
 
 [Hierarchy Navigation and the Subsystem Mutex]
 

Documentation/filesystems/configfs/configfs_example.c

-/*
- * vim: noexpandtab ts=8 sts=0 sw=8:
- *
- * configfs_example.c - This file is a demonstration module containing
- *      a number of configfs subsystems.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
- *
- * 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.
- *
- * 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 021110-1307, USA.
- *
- * Based on sysfs:
- * 	sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel
- *
- * configfs Copyright (C) 2005 Oracle.  All rights reserved.
- */
-
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-
-#include <linux/configfs.h>
-
-
-
-/*
- * 01-childless
- *
- * This first example is a childless subsystem.  It cannot create
- * any config_items.  It just has attributes.
- *
- * Note that we are enclosing the configfs_subsystem inside a container.
- * This is not necessary if a subsystem has no attributes directly
- * on the subsystem.  See the next example, 02-simple-children, for
- * such a subsystem.
- */
-
-struct childless {
-	struct configfs_subsystem subsys;
-	int showme;
-	int storeme;
-};
-
-struct childless_attribute {
-	struct configfs_attribute attr;
-	ssize_t (*show)(struct childless *, char *);
-	ssize_t (*store)(struct childless *, const char *, size_t);
-};
-
-static inline struct childless *to_childless(struct config_item *item)
-{
-	return item ? container_of(to_configfs_subsystem(to_config_group(item)), struct childless, subsys) : NULL;
-}
-
-static ssize_t childless_showme_read(struct childless *childless,
-				     char *page)
-{
-	ssize_t pos;
-
-	pos = sprintf(page, "%d\n", childless->showme);
-	childless->showme++;
-
-	return pos;
-}
-
-static ssize_t childless_storeme_read(struct childless *childless,
-				      char *page)
-{
-	return sprintf(page, "%d\n", childless->storeme);
-}
-
-static ssize_t childless_storeme_write(struct childless *childless,
-				       const char *page,
-				       size_t count)
-{
-	unsigned long tmp;
-	char *p = (char *) page;
-
-	tmp = simple_strtoul(p, &p, 10);
-	if (!p || (*p && (*p != '\n')))
-		return -EINVAL;
-
-	if (tmp > INT_MAX)
-		return -ERANGE;
-
-	childless->storeme = tmp;
-
-	return count;
-}
-
-static ssize_t childless_description_read(struct childless *childless,
-					  char *page)
-{
-	return sprintf(page,
-"[01-childless]\n"
-"\n"
-"The childless subsystem is the simplest possible subsystem in\n"
-"configfs.  It does not support the creation of child config_items.\n"
-"It only has a few attributes.  In fact, it isn't much different\n"
-"than a directory in /proc.\n");
-}
-
-static struct childless_attribute childless_attr_showme = {
-	.attr	= { .ca_owner = THIS_MODULE, .ca_name = "showme", .ca_mode = S_IRUGO },
-	.show	= childless_showme_read,
-};
-static struct childless_attribute childless_attr_storeme = {
-	.attr	= { .ca_owner = THIS_MODULE, .ca_name = "storeme", .ca_mode = S_IRUGO | S_IWUSR },
-	.show	= childless_storeme_read,
-	.store	= childless_storeme_write,
-};
-static struct childless_attribute childless_attr_description = {
-	.attr = { .ca_owner = THIS_MODULE, .ca_name = "description", .ca_mode = S_IRUGO },
-	.show = childless_description_read,
-};
-
-static struct configfs_attribute *childless_attrs[] = {
-	&childless_attr_showme.attr,
-	&childless_attr_storeme.attr,
-	&childless_attr_description.attr,
-	NULL,
-};
-
-static ssize_t childless_attr_show(struct config_item *item,
-				   struct configfs_attribute *attr,
-				   char *page)
-{
-	struct childless *childless = to_childless(item);
-	struct childless_attribute *childless_attr =
-		container_of(attr, struct childless_attribute, attr);
-	ssize_t ret = 0;
-
-	if (childless_attr->show)
-		ret = childless_attr->show(childless, page);
-	return ret;
-}
-
-static ssize_t childless_attr_store(struct config_item *item,
-				    struct configfs_attribute *attr,
-				    const char *page, size_t count)
-{
-	struct childless *childless = to_childless(item);
-	struct childless_attribute *childless_attr =
-		container_of(attr, struct childless_attribute, attr);
-	ssize_t ret = -EINVAL;
-
-	if (childless_attr->store)
-		ret = childless_attr->store(childless, page, count);
-	return ret;
-}
-
-static struct configfs_item_operations childless_item_ops = {
-	.show_attribute		= childless_attr_show,
-	.store_attribute	= childless_attr_store,
-};
-
-static struct config_item_type childless_type = {
-	.ct_item_ops	= &childless_item_ops,
-	.ct_attrs	= childless_attrs,
-	.ct_owner	= THIS_MODULE,
-};
-
-static struct childless childless_subsys = {
-	.subsys = {
-		.su_group = {
-			.cg_item = {
-				.ci_namebuf = "01-childless",
-				.ci_type = &childless_type,
-			},
-		},
-	},
-};
-
-
-/* ----------------------------------------------------------------- */
-
-/*
- * 02-simple-children
- *
- * This example merely has a simple one-attribute child.  Note that
- * there is no extra attribute structure, as the child's attribute is
- * known from the get-go.  Also, there is no container for the
- * subsystem, as it has no attributes of its own.
- */
-
-struct simple_child {
-	struct config_item item;
-	int storeme;
-};
-
-static inline struct simple_child *to_simple_child(struct config_item *item)
-{
-	return item ? container_of(item, struct simple_child, item) : NULL;
-}
-
-static struct configfs_attribute simple_child_attr_storeme = {
-	.ca_owner = THIS_MODULE,
-	.ca_name = "storeme",
-	.ca_mode = S_IRUGO | S_IWUSR,
-};
-
-static struct configfs_attribute *simple_child_attrs[] = {
-	&simple_child_attr_storeme,
-	NULL,
-};
-
-static ssize_t simple_child_attr_show(struct config_item *item,
-				      struct configfs_attribute *attr,
-				      char *page)
-{
-	ssize_t count;
-	struct simple_child *simple_child = to_simple_child(item);
-
-	count = sprintf(page, "%d\n", simple_child->storeme);
-
-	return count;
-}
-
-static ssize_t simple_child_attr_store(struct config_item *item,
-				       struct configfs_attribute *attr,
-				       const char *page, size_t count)
-{
-	struct simple_child *simple_child = to_simple_child(item);
-	unsigned long tmp;
-	char *p = (char *) page;
-
-	tmp = simple_strtoul(p, &p, 10);
-	if (!p || (*p && (*p != '\n')))
-		return -EINVAL;
-
-	if (tmp > INT_MAX)
-		return -ERANGE;
-
-	simple_child->storeme = tmp;
-
-	return count;
-}
-
-static void simple_child_release(struct config_item *item)
-{
-	kfree(to_simple_child(item));
-}
-
-static struct configfs_item_operations simple_child_item_ops = {
-	.release		= simple_child_release,
-	.show_attribute		= simple_child_attr_show,
-	.store_attribute	= simple_child_attr_store,
-};
-
-static struct config_item_type simple_child_type = {
-	.ct_item_ops	= &simple_child_item_ops,
-	.ct_attrs	= simple_child_attrs,
-	.ct_owner	= THIS_MODULE,
-};
-
-
-struct simple_children {
-	struct config_group group;
-};
-
-static inline struct simple_children *to_simple_children(struct config_item *item)
-{
-	return item ? container_of(to_config_group(item), struct simple_children, group) : NULL;
-}
-
-static struct config_item *simple_children_make_item(struct config_group *group, const char *name)
-{
-	struct simple_child *simple_child;
-
-	simple_child = kzalloc(sizeof(struct simple_child), GFP_KERNEL);
-	if (!simple_child)
-		return NULL;
-
-
-	config_item_init_type_name(&simple_child->item, name,
-				   &simple_child_type);
-
-	simple_child->storeme = 0;
-
-	return &simple_child->item;
-}
-
-static struct configfs_attribute simple_children_attr_description = {
-	.ca_owner = THIS_MODULE,
-	.ca_name = "description",
-	.ca_mode = S_IRUGO,
-};
-
-static struct configfs_attribute *simple_children_attrs[] = {
-	&simple_children_attr_description,
-	NULL,
-};
-
-static ssize_t simple_children_attr_show(struct config_item *item,
-			   		 struct configfs_attribute *attr,
-			   		 char *page)
-{
-	return sprintf(page,
-"[02-simple-children]\n"
-"\n"
-"This subsystem allows the creation of child config_items.  These\n"
-"items have only one attribute that is readable and writeable.\n");
-}
-
-static void simple_children_release(struct config_item *item)
-{
-	kfree(to_simple_children(item));
-}
-
-static struct configfs_item_operations simple_children_item_ops = {
-	.release 	= simple_children_release,
-	.show_attribute	= simple_children_attr_show,
-};
-
-/*
- * Note that, since no extra work is required on ->drop_item(),
- * no ->drop_item() is provided.
- */
-static struct configfs_group_operations simple_children_group_ops = {
-	.make_item	= simple_children_make_item,
-};
-
-static struct config_item_type simple_children_type = {
-	.ct_item_ops	= &simple_children_item_ops,
-	.ct_group_ops	= &simple_children_group_ops,
-	.ct_attrs	= simple_children_attrs,
-	.ct_owner	= THIS_MODULE,
-};
-
-static struct configfs_subsystem simple_children_subsys = {
-	.su_group = {
-		.cg_item = {
-			.ci_namebuf = "02-simple-children",
-			.ci_type = &simple_children_type,
-		},
-	},
-};
-
-
-/* ----------------------------------------------------------------- */
-
-/*
- * 03-group-children
- *
- * This example reuses the simple_children group from above.  However,
- * the simple_children group is not the subsystem itself, it is a
- * child of the subsystem.  Creation of a group in the subsystem creates
- * a new simple_children group.  That group can then have simple_child
- * children of its own.
- */
-
-static struct config_group *group_children_make_group(struct config_group *group, const char *name)
-{
-	struct simple_children *simple_children;
-
-	simple_children = kzalloc(sizeof(struct simple_children),
-				  GFP_KERNEL);
-	if (!simple_children)
-		return NULL;
-
-
-	config_group_init_type_name(&simple_children->group, name,
-				    &simple_children_type);
-
-	return &simple_children->group;
-}
-
-static struct configfs_attribute group_children_attr_description = {
-	.ca_owner = THIS_MODULE,
-	.ca_name = "description",
-	.ca_mode = S_IRUGO,
-};
-
-static struct configfs_attribute *group_children_attrs[] = {
-	&group_children_attr_description,
-	NULL,
-};
-
-static ssize_t group_children_attr_show(struct config_item *item,
-			   		struct configfs_attribute *attr,
-			   		char *page)
-{
-	return sprintf(page,
-"[03-group-children]\n"
-"\n"
-"This subsystem allows the creation of child config_groups.  These\n"
-"groups are like the subsystem simple-children.\n");
-}
-
-static struct configfs_item_operations group_children_item_ops = {
-	.show_attribute	= group_children_attr_show,
-};
-
-/*
- * Note that, since no extra work is required on ->drop_item(),
- * no ->drop_item() is provided.
- */
-static struct configfs_group_operations group_children_group_ops = {
-	.make_group	= group_children_make_group,
-};
-
-static struct config_item_type group_children_type = {
-	.ct_item_ops	= &group_children_item_ops,
-	.ct_group_ops	= &group_children_group_ops,
-	.ct_attrs	= group_children_attrs,
-	.ct_owner	= THIS_MODULE,
-};
-
-static struct configfs_subsystem group_children_subsys = {
-	.su_group = {
-		.cg_item = {
-			.ci_namebuf = "03-group-children",
-			.ci_type = &group_children_type,
-		},
-	},
-};
-
-/* ----------------------------------------------------------------- */
-
-/*
- * We're now done with our subsystem definitions.
- * For convenience in this module, here's a list of them all.  It
- * allows the init function to easily register them.  Most modules
- * will only have one subsystem, and will only call register_subsystem
- * on it directly.
- */
-static struct configfs_subsystem *example_subsys[] = {
-	&childless_subsys.subsys,
-	&simple_children_subsys,
-	&group_children_subsys,
-	NULL,
-};
-
-static int __init configfs_example_init(void)
-{
-	int ret;
-	int i;
-	struct configfs_subsystem *subsys;
-
-	for (i = 0; example_subsys[i]; i++) {
-		subsys = example_subsys[i];
-
-		config_group_init(&subsys->su_group);
-		mutex_init(&subsys->su_mutex);
-		ret = configfs_register_subsystem(subsys);
-		if (ret) {
-			printk(KERN_ERR "Error %d while registering subsystem %s\n",
-			       ret,
-			       subsys->su_group.cg_item.ci_namebuf);
-			goto out_unregister;
-		}
-	}
-
-	return 0;
-
-out_unregister:
-	for (; i >= 0; i--) {
-		configfs_unregister_subsystem(example_subsys[i]);
-	}
-
-	return ret;
-}
-
-static void __exit configfs_example_exit(void)
-{
-	int i;
-
-	for (i = 0; example_subsys[i]; i++) {
-		configfs_unregister_subsystem(example_subsys[i]);
-	}
-}
-
-module_init(configfs_example_init);
-module_exit(configfs_example_exit);
-MODULE_LICENSE("GPL");

Documentation/filesystems/configfs/configfs_example_explicit.c

+/*
+ * vim: noexpandtab ts=8 sts=0 sw=8:
+ *
+ * configfs_example_explicit.c - This file is a demonstration module
+ *      containing a number of configfs subsystems.  It explicitly defines
+ *      each structure without using the helper macros defined in
+ *      configfs.h.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ * 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 021110-1307, USA.
+ *
+ * Based on sysfs:
+ * 	sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel
+ *
+ * configfs Copyright (C) 2005 Oracle.  All rights reserved.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include <linux/configfs.h>
+
+
+
+/*
+ * 01-childless
+ *
+ * This first example is a childless subsystem.  It cannot create
+ * any config_items.  It just has attributes.
+ *
+ * Note that we are enclosing the configfs_subsystem inside a container.
+ * This is not necessary if a subsystem has no attributes directly
+ * on the subsystem.  See the next example, 02-simple-children, for
+ * such a subsystem.
+ */
+
+struct childless {
+	struct configfs_subsystem subsys;
+	int showme;
+	int storeme;
+};
+
+struct childless_attribute {
+	struct configfs_attribute attr;
+	ssize_t (*show)(struct childless *, char *);
+	ssize_t (*store)(struct childless *, const char *, size_t);
+};
+
+static inline struct childless *to_childless(struct config_item *item)
+{
+	return item ? container_of(to_configfs_subsystem(to_config_group(item)), struct childless, subsys) : NULL;
+}
+
+static ssize_t childless_showme_read(struct childless *childless,
+				     char *page)
+{
+	ssize_t pos;
+
+	pos = sprintf(page, "%d\n", childless->showme);
+	childless->showme++;
+
+	return pos;
+}
+
+static ssize_t childless_storeme_read(struct childless *childless,
+				      char *page)
+{
+	return sprintf(page, "%d\n", childless->storeme);
+}
+
+static ssize_t childless_storeme_write(struct childless *childless,
+				       const char *page,
+				       size_t count)
+{
+	unsigned long tmp;
+	char *p = (char *) page;
+
+	tmp = simple_strtoul(p, &p, 10);
+	if (!p || (*p && (*p != '\n')))
+		return -EINVAL;
+
+	if (tmp > INT_MAX)
+		return -ERANGE;
+
+	childless->storeme = tmp;
+
+	return count;
+}
+
+static ssize_t childless_description_read(struct childless *childless,
+					  char *page)
+{
+	return sprintf(page,
+"[01-childless]\n"
+"\n"
+"The childless subsystem is the simplest possible subsystem in\n"
+"configfs.  It does not support the creation of child config_items.\n"
+"It only has a few attributes.  In fact, it isn't much different\n"
+"than a directory in /proc.\n");
+}
+
+static struct childless_attribute childless_attr_showme = {
+	.attr	= { .ca_owner = THIS_MODULE, .ca_name = "showme", .ca_mode = S_IRUGO },
+	.show	= childless_showme_read,
+};
+static struct childless_attribute childless_attr_storeme = {
+	.attr	= { .ca_owner = THIS_MODULE, .ca_name = "storeme", .ca_mode = S_IRUGO | S_IWUSR },
+	.show	= childless_storeme_read,
+	.store	= childless_storeme_write,
+};
+static struct childless_attribute childless_attr_description = {
+	.attr = { .ca_owner = THIS_MODULE, .ca_name = "description", .ca_mode = S_IRUGO },
+	.show = childless_description_read,
+};
+
+static struct configfs_attribute *childless_attrs[] = {
+	&childless_attr_showme.attr,
+	&childless_attr_storeme.attr,
+	&childless_attr_description.attr,
+	NULL,
+};
+
+static ssize_t childless_attr_show(struct config_item *item,
+				   struct configfs_attribute *attr,
+				   char *page)
+{
+	struct childless *childless = to_childless(item);
+	struct childless_attribute *childless_attr =
+		container_of(attr, struct childless_attribute, attr);
+	ssize_t ret = 0;
+
+	if (childless_attr->show)
+		ret = childless_attr->show(childless, page);
+	return ret;
+}
+
+static ssize_t childless_attr_store(struct config_item *item,
+				    struct configfs_attribute *attr,
+				    const char *page, size_t count)
+{
+	struct childless *childless = to_childless(item);
+	struct childless_attribute *childless_attr =
+		container_of(attr, struct childless_attribute, attr);
+	ssize_t ret = -EINVAL;
+
+	if (childless_attr->store)
+		ret = childless_attr->store(childless, page, count);
+	return ret;
+}
+
+static struct configfs_item_operations childless_item_ops = {
+	.show_attribute		= childless_attr_show,
+	.store_attribute	= childless_attr_store,
+};
+
+static struct config_item_type childless_type = {
+	.ct_item_ops	= &childless_item_ops,
+	.ct_attrs	= childless_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static struct childless childless_subsys = {
+	.subsys = {
+		.su_group = {
+			.cg_item = {
+				.ci_namebuf = "01-childless",
+				.ci_type = &childless_type,
+			},
+		},
+	},
+};
+
+
+/* ----------------------------------------------------------------- */
+
+/*
+ * 02-simple-children
+ *
+ * This example merely has a simple one-attribute child.  Note that
+ * there is no extra attribute structure, as the child's attribute is
+ * known from the get-go.  Also, there is no container for the
+ * subsystem, as it has no attributes of its own.
+ */
+
+struct simple_child {
+	struct config_item item;
+	int storeme;
+};
+
+static inline struct simple_child *to_simple_child(struct config_item *item)
+{
+	return item ? container_of(item, struct simple_child, item) : NULL;
+}
+
+static struct configfs_attribute simple_child_attr_storeme = {
+	.ca_owner = THIS_MODULE,
+	.ca_name = "storeme",
+	.ca_mode = S_IRUGO | S_IWUSR,
+};
+
+static struct configfs_attribute *simple_child_attrs[] = {
+	&simple_child_attr_storeme,
+	NULL,
+};
+
+static ssize_t simple_child_attr_show(struct config_item *item,
+				      struct configfs_attribute *attr,
+				      char *page)
+{
+	ssize_t count;
+	struct simple_child *simple_child = to_simple_child(item);
+
+	count = sprintf(page, "%d\n", simple_child->storeme);
+
+	return count;
+}
+
+static ssize_t simple_child_attr_store(struct config_item *item,
+				       struct configfs_attribute *attr,
+				       const char *page, size_t count)
+{
+	struct simple_child *simple_child = to_simple_child(item);
+	unsigned long tmp;
+	char *p = (char *) page;
+
+	tmp = simple_strtoul(p, &p, 10);
+	if (!p || (*p && (*p != '\n')))
+		return -EINVAL;
+
+	if (tmp > INT_MAX)
+		return -ERANGE;
+
+	simple_child->storeme = tmp;
+
+	return count;
+}
+
+static void simple_child_release(struct config_item *item)
+{
+	kfree(to_simple_child(item));
+}
+
+static struct configfs_item_operations simple_child_item_ops = {
+	.release		= simple_child_release,
+	.show_attribute		= simple_child_attr_show,
+	.store_attribute	= simple_child_attr_store,
+};
+
+static struct config_item_type simple_child_type = {
+	.ct_item_ops	= &simple_child_item_ops,
+	.ct_attrs	= simple_child_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+
+struct simple_children {
+	struct config_group group;
+};
+
+static inline struct simple_children *to_simple_children(struct config_item *item)
+{
+	return item ? container_of(to_config_group(item), struct simple_children, group) : NULL;
+}
+
+static struct config_item *simple_children_make_item(struct config_group *group, const char *name)
+{
+	struct simple_child *simple_child;
+
+	simple_child = kzalloc(sizeof(struct simple_child), GFP_KERNEL);
+	if (!simple_child)
+		return ERR_PTR(-ENOMEM);
+
+	config_item_init_type_name(&simple_child->item, name,
+				   &simple_child_type);
+
+	simple_child->storeme = 0;
+
+	return &simple_child->item;
+}
+
+static struct configfs_attribute simple_children_attr_description = {
+	.ca_owner = THIS_MODULE,
+	.ca_name = "description",
+	.ca_mode = S_IRUGO,
+};
+
+static struct configfs_attribute *simple_children_attrs[] = {
+	&simple_children_attr_description,
+	NULL,
+};
+
+static ssize_t simple_children_attr_show(struct config_item *item,
+					 struct configfs_attribute *attr,
+					 char *page)
+{
+	return sprintf(page,
+"[02-simple-children]\n"
+"\n"
+"This subsystem allows the creation of child config_items.  These\n"
+"items have only one attribute that is readable and writeable.\n");
+}
+
+static void simple_children_release(struct config_item *item)
+{
+	kfree(to_simple_children(item));
+}
+
+static struct configfs_item_operations simple_children_item_ops = {
+	.release	= simple_children_release,
+	.show_attribute	= simple_children_attr_show,
+};
+
+/*
+ * Note that, since no extra work is required on ->drop_item(),
+ * no ->drop_item() is provided.
+ */
+static struct configfs_group_operations simple_children_group_ops = {
+	.make_item	= simple_children_make_item,
+};
+
+static struct config_item_type simple_children_type = {
+	.ct_item_ops	= &simple_children_item_ops,
+	.ct_group_ops	= &simple_children_group_ops,
+	.ct_attrs	= simple_children_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static struct configfs_subsystem simple_children_subsys = {
+	.su_group = {
+		.cg_item = {
+			.ci_namebuf = "02-simple-children",
+			.ci_type = &simple_children_type,
+		},
+	},
+};
+
+
+/* ----------------------------------------------------------------- */
+
+/*
+ * 03-group-children
+ *
+ * This example reuses the simple_children group from above.  However,
+ * the simple_children group is not the subsystem itself, it is a
+ * child of the subsystem.  Creation of a group in the subsystem creates
+ * a new simple_children group.  That group can then have simple_child
+ * children of its own.
+ */
+
+static struct config_group *group_children_make_group(struct config_group *group, const char *name)
+{
+	struct simple_children *simple_children;
+
+	simple_children = kzalloc(sizeof(struct simple_children),
+				  GFP_KERNEL);
+	if (!simple_children)
+		return ERR_PTR(-ENOMEM);
+
+	config_group_init_type_name(&simple_children->group, name,
+				    &simple_children_type);
+
+	return &simple_children->group;
+}
+
+static struct configfs_attribute group_children_attr_description = {
+	.ca_owner = THIS_MODULE,
+	.ca_name = "description",
+	.ca_mode = S_IRUGO,
+};
+
+static struct configfs_attribute *group_children_attrs[] = {
+	&group_children_attr_description,
+	NULL,
+};
+
+static ssize_t group_children_attr_show(struct config_item *item,
+					struct configfs_attribute *attr,
+					char *page)
+{
+	return sprintf(page,
+"[03-group-children]\n"
+"\n"
+"This subsystem allows the creation of child config_groups.  These\n"
+"groups are like the subsystem simple-children.\n");
+}
+
+static struct configfs_item_operations group_children_item_ops = {
+	.show_attribute	= group_children_attr_show,
+};
+
+/*
+ * Note that, since no extra work is required on ->drop_item(),
+ * no ->drop_item() is provided.
+ */
+static struct configfs_group_operations group_children_group_ops = {
+	.make_group	= group_children_make_group,
+};
+
+static struct config_item_type group_children_type = {
+	.ct_item_ops	= &group_children_item_ops,
+	.ct_group_ops	= &group_children_group_ops,
+	.ct_attrs	= group_children_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static struct configfs_subsystem group_children_subsys = {
+	.su_group = {
+		.cg_item = {
+			.ci_namebuf = "03-group-children",
+			.ci_type = &group_children_type,
+		},
+	},
+};
+
+/* ----------------------------------------------------------------- */
+
+/*
+ * We're now done with our subsystem definitions.
+ * For convenience in this module, here's a list of them all.  It
+ * allows the init function to easily register them.  Most modules
+ * will only have one subsystem, and will only call register_subsystem
+ * on it directly.
+ */
+static struct configfs_subsystem *example_subsys[] = {
+	&childless_subsys.subsys,
+	&simple_children_subsys,
+	&group_children_subsys,
+	NULL,
+};
+
+static int __init configfs_example_init(void)
+{
+	int ret;
+	int i;
+	struct configfs_subsystem *subsys;
+
+	for (i = 0; example_subsys[i]; i++) {
+		subsys = example_subsys[i];
+
+		config_group_init(&subsys->su_group);
+		mutex_init(&subsys->su_mutex);
+		ret = configfs_register_subsystem(subsys);
+		if (ret) {
+			printk(KERN_ERR "Error %d while registering subsystem %s\n",
+			       ret,
+			       subsys->su_group.cg_item.ci_namebuf);
+			goto out_unregister;
+		}
+	}
+
+	return 0;
+
+out_unregister:
+	for (; i >= 0; i--) {
+		configfs_unregister_subsystem(example_subsys[i]);
+	}
+
+	return ret;
+}
+
+static void __exit configfs_example_exit(void)
+{
+	int i;
+
+	for (i = 0; example_subsys[i]; i++) {
+		configfs_unregister_subsystem(example_subsys[i]);
+	}
+}
+
+module_init(configfs_example_init);
+module_exit(configfs_example_exit);
+MODULE_LICENSE("GPL");

Documentation/filesystems/configfs/configfs_example_macros.c

+/*
+ * vim: noexpandtab ts=8 sts=0 sw=8:
+ *
+ * configfs_example_macros.c - This file is a demonstration module
+ *      containing a number of configfs subsystems.  It uses the helper
+ *      macros defined by configfs.h
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ * 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 021110-1307, USA.
+ *
+ * Based on sysfs:
+ * 	sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel
+ *
+ * configfs Copyright (C) 2005 Oracle.  All rights reserved.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include <linux/configfs.h>
+
+
+
+/*
+ * 01-childless
+ *
+ * This first example is a childless subsystem.  It cannot create
+ * any config_items.  It just has attributes.
+ *
+ * Note that we are enclosing the configfs_subsystem inside a container.
+ * This is not necessary if a subsystem has no attributes directly
+ * on the subsystem.  See the next example, 02-simple-children, for
+ * such a subsystem.
+ */
+
+struct childless {
+	struct configfs_subsystem subsys;
+	int showme;
+	int storeme;
+};
+
+static inline struct childless *to_childless(struct config_item *item)
+{
+	return item ? container_of(to_configfs_subsystem(to_config_group(item)), struct childless, subsys) : NULL;
+}
+
+CONFIGFS_ATTR_STRUCT(childless);
+#define CHILDLESS_ATTR(_name, _mode, _show, _store)	\
+struct childless_attribute childless_attr_##_name = __CONFIGFS_ATTR(_name, _mode, _show, _store)
+#define CHILDLESS_ATTR_RO(_name, _show)	\
+struct childless_attribute childless_attr_##_name = __CONFIGFS_ATTR_RO(_name, _show);
+
+static ssize_t childless_showme_read(struct childless *childless,
+				     char *page)
+{
+	ssize_t pos;
+
+	pos = sprintf(page, "%d\n", childless->showme);
+	childless->showme++;
+
+	return pos;
+}
+
+static ssize_t childless_storeme_read(struct childless *childless,
+				      char *page)
+{
+	return sprintf(page, "%d\n", childless->storeme);
+}
+
+static ssize_t childless_storeme_write(struct childless *childless,
+				       const char *page,
+				       size_t count)
+{
+	unsigned long tmp;
+	char *p = (char *) page;
+
+	tmp = simple_strtoul(p, &p, 10);
+	if (!p || (*p && (*p != '\n')))
+		return -EINVAL;
+
+	if (tmp > INT_MAX)
+		return -ERANGE;
+
+	childless->storeme = tmp;
+
+	return count;
+}
+
+static ssize_t childless_description_read(struct childless *childless,
+					  char *page)
+{
+	return sprintf(page,
+"[01-childless]\n"
+"\n"
+"The childless subsystem is the simplest possible subsystem in\n"
+"configfs.  It does not support the creation of child config_items.\n"
+"It only has a few attributes.  In fact, it isn't much different\n"
+"than a directory in /proc.\n");
+}
+
+CHILDLESS_ATTR_RO(showme, childless_showme_read);
+CHILDLESS_ATTR(storeme, S_IRUGO | S_IWUSR, childless_storeme_read,
+	       childless_storeme_write);
+CHILDLESS_ATTR_RO(description, childless_description_read);
+
+static struct configfs_attribute *childless_attrs[] = {
+	&childless_attr_showme.attr,
+	&childless_attr_storeme.attr,
+	&childless_attr_description.attr,
+	NULL,
+};
+
+CONFIGFS_ATTR_OPS(childless);
+static struct configfs_item_operations childless_item_ops = {
+	.show_attribute		= childless_attr_show,
+	.store_attribute	= childless_attr_store,
+};
+
+static struct config_item_type childless_type = {
+	.ct_item_ops	= &childless_item_ops,
+	.ct_attrs	= childless_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static struct childless childless_subsys = {
+	.subsys = {
+		.su_group = {
+			.cg_item = {
+				.ci_namebuf = "01-childless",
+				.ci_type = &childless_type,
+			},
+		},
+	},
+};
+
+
+/* ----------------------------------------------------------------- */
+
+/*
+ * 02-simple-children
+ *
+ * This example merely has a simple one-attribute child.  Note that
+ * there is no extra attribute structure, as the child's attribute is
+ * known from the get-go.  Also, there is no container for the
+ * subsystem, as it has no attributes of its own.
+ */
+
+struct simple_child {
+	struct config_item item;
+	int storeme;
+};
+
+static inline struct simple_child *to_simple_child(struct config_item *item)
+{
+	return item ? container_of(item, struct simple_child, item) : NULL;
+}
+
+static struct configfs_attribute simple_child_attr_storeme = {
+	.ca_owner = THIS_MODULE,
+	.ca_name = "storeme",
+	.ca_mode = S_IRUGO | S_IWUSR,
+};
+
+static struct configfs_attribute *simple_child_attrs[] = {
+	&simple_child_attr_storeme,
+	NULL,
+};
+
+static ssize_t simple_child_attr_show(struct config_item *item,
+				      struct configfs_attribute *attr,
+				      char *page)
+{
+	ssize_t count;
+	struct simple_child *simple_child = to_simple_child(item);
+
+	count = sprintf(page, "%d\n", simple_child->storeme);
+
+	return count;
+}
+
+static ssize_t simple_child_attr_store(struct config_item *item,
+				       struct configfs_attribute *attr,
+				       const char *page, size_t count)
+{
+	struct simple_child *simple_child = to_simple_child(item);
+	unsigned long tmp;
+	char *p = (char *) page;
+
+	tmp = simple_strtoul(p, &p, 10);
+	if (!p || (*p && (*p != '\n')))
+		return -EINVAL;
+
+	if (tmp > INT_MAX)
+		return -ERANGE;
+
+	simple_child->storeme = tmp;
+
+	return count;
+}
+
+static void simple_child_release(struct config_item *item)
+{
+	kfree(to_simple_child(item));
+}
+
+static struct configfs_item_operations simple_child_item_ops = {
+	.release		= simple_child_release,
+	.show_attribute		= simple_child_attr_show,
+	.store_attribute	= simple_child_attr_store,
+};
+
+static struct config_item_type simple_child_type = {
+	.ct_item_ops	= &simple_child_item_ops,
+	.ct_attrs	= simple_child_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+
+struct simple_children {
+	struct config_group group;
+};
+
+static inline struct simple_children *to_simple_children(struct config_item *item)
+{
+	return item ? container_of(to_config_group(item), struct simple_children, group) : NULL;
+}
+
+static struct config_item *simple_children_make_item(struct config_group *group, const char *name)
+{
+	struct simple_child *simple_child;
+
+	simple_child = kzalloc(sizeof(struct simple_child), GFP_KERNEL);
+	if (!simple_child)
+		return ERR_PTR(-ENOMEM);
+
+	config_item_init_type_name(&simple_child->item, name,
+				   &simple_child_type);
+
+	simple_child->storeme = 0;
+
+	return &simple_child->item;
+}
+
+static struct configfs_attribute simple_children_attr_description = {
+	.ca_owner = THIS_MODULE,
+	.ca_name = "description",
+	.ca_mode = S_IRUGO,
+};
+
+static struct configfs_attribute *simple_children_attrs[] = {
+	&simple_children_attr_description,
+	NULL,
+};
+
+static ssize_t simple_children_attr_show(struct config_item *item,
+					 struct configfs_attribute *attr,
+					 char *page)
+{
+	return sprintf(page,
+"[02-simple-children]\n"
+"\n"
+"This subsystem allows the creation of child config_items.  These\n"
+"items have only one attribute that is readable and writeable.\n");
+}
+
+static void simple_children_release(struct config_item *item)
+{
+	kfree(to_simple_children(item));
+}
+
+static struct configfs_item_operations simple_children_item_ops = {
+	.release	= simple_children_release,
+	.show_attribute	= simple_children_attr_show,
+};
+
+/*
+ * Note that, since no extra work is required on ->drop_item(),
+ * no ->drop_item() is provided.
+ */
+static struct configfs_group_operations simple_children_group_ops = {
+	.make_item	= simple_children_make_item,
+};
+
+static struct config_item_type simple_children_type = {
+	.ct_item_ops	= &simple_children_item_ops,
+	.ct_group_ops	= &simple_children_group_ops,
+	.ct_attrs	= simple_children_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static struct configfs_subsystem simple_children_subsys = {
+	.su_group = {
+		.cg_item = {
+			.ci_namebuf = "02-simple-children",
+			.ci_type = &simple_children_type,
+		},
+	},
+};
+
+
+/* ----------------------------------------------------------------- */
+
+/*
+ * 03-group-children
+ *
+ * This example reuses the simple_children group from above.  However,
+ * the simple_children group is not the subsystem itself, it is a
+ * child of the subsystem.  Creation of a group in the subsystem creates
+ * a new simple_children group.  That group can then have simple_child
+ * children of its own.
+ */
+
+static struct config_group *group_children_make_group(struct config_group *group, const char *name)
+{
+	struct simple_children *simple_children;
+
+	simple_children = kzalloc(sizeof(struct simple_children),
+				  GFP_KERNEL);
+	if (!simple_children)
+		return ERR_PTR(-ENOMEM);
+
+	config_group_init_type_name(&simple_children->group, name,
+				    &simple_children_type);
+
+	return &simple_children->group;
+}
+
+static struct configfs_attribute group_children_attr_description = {
+	.ca_owner = THIS_MODULE,
+	.ca_name = "description",
+	.ca_mode = S_IRUGO,
+};
+
+static struct configfs_attribute *group_children_attrs[] = {
+	&group_children_attr_description,
+	NULL,
+};
+
+static ssize_t group_children_attr_show(struct config_item *item,
+					struct configfs_attribute *attr,
+					char *page)
+{
+	return sprintf(page,
+"[03-group-children]\n"
+"\n"
+"This subsystem allows the creation of child config_groups.  These\n"
+"groups are like the subsystem simple-children.\n");
+}
+
+static struct configfs_item_operations group_children_item_ops = {
+	.show_attribute	= group_children_attr_show,
+};
+
+/*
+ * Note that, since no extra work is required on ->drop_item(),
+ * no ->drop_item() is provided.
+ */
+static struct configfs_group_operations group_children_group_ops = {
+	.make_group	= group_children_make_group,
+};
+
+static struct config_item_type group_children_type = {
+	.ct_item_ops	= &group_children_item_ops,
+	.ct_group_ops	= &group_children_group_ops,
+	.ct_attrs	= group_children_attrs,
+	.ct_owner	= THIS_MODULE,
+};
+
+static struct configfs_subsystem group_children_subsys = {
+	.su_group = {
+		.cg_item = {
+			.ci_namebuf = "03-group-children",
+			.ci_type = &group_children_type,
+		},
+	},
+};
+
+/* ----------------------------------------------------------------- */
+
+/*
+ * We're now done with our subsystem definitions.
+ * For convenience in this module, here's a list of them all.  It
+ * allows the init function to easily register them.  Most modules
+ * will only have one subsystem, and will only call register_subsystem
+ * on it directly.
+ */
+static struct configfs_subsystem *example_subsys[] = {
+	&childless_subsys.subsys,
+	&simple_children_subsys,
+	&group_children_subsys,
+	NULL,
+};
+
+static int __init configfs_example_init(void)
+{
+	int ret;
+	int i;
+	struct configfs_subsystem *subsys;
+
+	for (i = 0; example_subsys[i]; i++) {
+		subsys = example_subsys[i];
+
+		config_group_init(&subsys->su_group);
+		mutex_init(&subsys->su_mutex);
+		ret = configfs_register_subsystem(subsys);
+		if (ret) {
+			printk(KERN_ERR "Error %d while registering subsystem %s\n",
+			       ret,
+			       subsys->su_group.cg_item.ci_namebuf);
+			goto out_unregister;
+		}
+	}
+
+	return 0;
+
+out_unregister:
+	for (; i >= 0; i--) {
+		configfs_unregister_subsystem(example_subsys[i]);
+	}
+
+	return ret;
+}
+
+static void __exit configfs_example_exit(void)
+{
+	int i;
+
+	for (i = 0; example_subsys[i]; i++) {
+		configfs_unregister_subsystem(example_subsys[i]);
+	}
+}
+
+module_init(configfs_example_init);
+module_exit(configfs_example_exit);
+MODULE_LICENSE("GPL");

Documentation/filesystems/nfs-rdma.txt

@@ -5,7 +5,7 @@
 ################################################################################
 
  Author: NetApp and Open Grid Computing
- Date: April 15, 2008
+ Date: May 29, 2008
 
 Table of Contents
 ~~~~~~~~~~~~~~~~~
@@ -60,16 +60,18 @@ Installation
     The procedures described in this document have been tested with
     distributions from Red Hat's Fedora Project (http://fedora.redhat.com/).
 
-  - Install nfs-utils-1.1.1 or greater on the client
+  - Install nfs-utils-1.1.2 or greater on the client
 
-    An NFS/RDMA mount point can only be obtained by using the mount.nfs
-    command in nfs-utils-1.1.1 or greater. To see which version of mount.nfs
-    you are using, type:
+    An NFS/RDMA mount point can be obtained by using the mount.nfs command in
+    nfs-utils-1.1.2 or greater (nfs-utils-1.1.1 was the first nfs-utils
+    version with support for NFS/RDMA mounts, but for various reasons we
+    recommend using nfs-utils-1.1.2 or greater). To see which version of
+    mount.nfs you are using, type:
 
-    > /sbin/mount.nfs -V
+    $ /sbin/mount.nfs -V
 
-    If the version is less than 1.1.1 or the command does not exist,
-    then you will need to install the latest version of nfs-utils.
+    If the version is less than 1.1.2 or the command does not exist,
+    you should install the latest version of nfs-utils.
 
     Download the latest package from:
 
@@ -77,22 +79,33 @@ Installation
 
     Uncompress the package and follow the installation instructions.
 
-    If you will not be using GSS and NFSv4, the installation process
-    can be simplified by disabling these features when running configure:
+    If you will not need the idmapper and gssd executables (you do not need
+    these to create an NFS/RDMA enabled mount command), the installation
+    process can be simplified by disabling these features when running
+    configure:
 
-    > ./configure --disable-gss --disable-nfsv4
+    $ ./configure --disable-gss --disable-nfsv4
 
-    For more information on this see the package's README and INSTALL files.
+    To build nfs-utils you will need the tcp_wrappers package installed. For
+    more information on this see the package's README and INSTALL files.
 
     After building the nfs-utils package, there will be a mount.nfs binary in
     the utils/mount directory. This binary can be used to initiate NFS v2, v3,
-    or v4 mounts. To initiate a v4 mount, the binary must be called mount.nfs4.
-    The standard technique is to create a symlink called mount.nfs4 to mount.nfs.
+    or v4 mounts. To initiate a v4 mount, the binary must be called
+    mount.nfs4.  The standard technique is to create a symlink called
+    mount.nfs4 to mount.nfs.
 
-    NOTE: mount.nfs and therefore nfs-utils-1.1.1 or greater is only needed
+    This mount.nfs binary should be installed at /sbin/mount.nfs as follows:
+
+    $ sudo cp utils/mount/mount.nfs /sbin/mount.nfs
+
+    In this location, mount.nfs will be invoked automatically for NFS mounts
+    by the system mount commmand.
+
+    NOTE: mount.nfs and therefore nfs-utils-1.1.2 or greater is only needed
     on the NFS client machine. You do not need this specific version of
     nfs-utils on the server. Furthermore, only the mount.nfs command from
-    nfs-utils-1.1.1 is needed on the client.
+    nfs-utils-1.1.2 is needed on the client.
 
   - Install a Linux kernel with NFS/RDMA
 
@@ -156,8 +169,8 @@ Check RDMA and NFS Setup
     this time. For example, if you are using a Mellanox Tavor/Sinai/Arbel
     card:
 
-    > modprobe ib_mthca
-    > modprobe ib_ipoib
+    $ modprobe ib_mthca
+    $ modprobe ib_ipoib
 
     If you are using InfiniBand, make sure there is a Subnet Manager (SM)
     running on the network. If your IB switch has an embedded SM, you can
@@ -166,7 +179,7 @@ Check RDMA and NFS Setup
 
     If an SM is running on your network, you should see the following:
 
-    > cat /sys/class/infiniband/driverX/ports/1/state
+    $ cat /sys/class/infiniband/driverX/ports/1/state
     4: ACTIVE
 
     where driverX is mthca0, ipath5, ehca3, etc.
@@ -174,10 +187,10 @@ Check RDMA and NFS Setup
     To further test the InfiniBand software stack, use IPoIB (this
     assumes you have two IB hosts named host1 and host2):
 
-    host1> ifconfig ib0 a.b.c.x
-    host2> ifconfig ib0 a.b.c.y
-    host1> ping a.b.c.y
-    host2> ping a.b.c.x
+    host1$ ifconfig ib0 a.b.c.x
+    host2$ ifconfig ib0 a.b.c.y
+    host1$ ping a.b.c.y
+    host2$ ping a.b.c.x
 
     For other device types, follow the appropriate procedures.
 
@@ -202,11 +215,11 @@ NFS/RDMA Setup
     /vol0   192.168.0.47(fsid=0,rw,async,insecure,no_root_squash)
     /vol0   192.168.0.0/255.255.255.0(fsid=0,rw,async,insecure,no_root_squash)
 
-    The IP address(es) is(are) the client's IPoIB address for an InfiniBand HCA or the
-    cleint's iWARP address(es) for an RNIC.
+    The IP address(es) is(are) the client's IPoIB address for an InfiniBand
+    HCA or the cleint's iWARP address(es) for an RNIC.
 
-    NOTE: The "insecure" option must be used because the NFS/RDMA client does not
-    use a reserved port.
+    NOTE: The "insecure" option must be used because the NFS/RDMA client does
+    not use a reserved port.
 
  Each time a machine boots:
 
@@ -214,43 +227,45 @@ NFS/RDMA Setup
 
     For InfiniBand using a Mellanox adapter:
 
-    > modprobe ib_mthca
-    > modprobe ib_ipoib
-    > ifconfig ib0 a.b.c.d
+    $ modprobe ib_mthca
+    $ modprobe ib_ipoib
+    $ ifconfig ib0 a.b.c.d
 
     NOTE: use unique addresses for the client and server
 
   - Start the NFS server
 
-    If the NFS/RDMA server was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in kernel config),
-    load the RDMA transport module:
+    If the NFS/RDMA server was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in
+    kernel config), load the RDMA transport module:
 
-    > modprobe svcrdma
+    $ modprobe svcrdma
 
-    Regardless of how the server was built (module or built-in), start the server:
+    Regardless of how the server was built (module or built-in), start the
+    server:
 
-    > /etc/init.d/nfs start
+    $ /etc/init.d/nfs start
 
     or
 
-    > service nfs start
+    $ service nfs start
 
     Instruct the server to listen on the RDMA transport:
 
-    > echo rdma 2050 > /proc/fs/nfsd/portlist
+    $ echo rdma 2050 > /proc/fs/nfsd/portlist
 
   - On the client system
 
-    If the NFS/RDMA client was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in kernel config),
-    load the RDMA client module:
+    If the NFS/RDMA client was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in
+    kernel config), load the RDMA client module:
 
-    > modprobe xprtrdma.ko
+    $ modprobe xprtrdma.ko
 
-    Regardless of how the client was built (module or built-in), issue the mount.nfs command:
+    Regardless of how the client was built (module or built-in), use this
+    command to mount the NFS/RDMA server:
 
-    > /path/to/your/mount.nfs <IPoIB-server-name-or-address>:/<export> /mnt -i -o rdma,port=2050
+    $ mount -o rdma,port=2050 <IPoIB-server-name-or-address>:/<export> /mnt
 
-    To verify that the mount is using RDMA, run "cat /proc/mounts" and check the
-    "proto" field for the given mount.
+    To verify that the mount is using RDMA, run "cat /proc/mounts" and check
+    the "proto" field for the given mount.
 
   Congratulations! You're using NFS/RDMA!

Documentation/filesystems/omfs.txt

+Optimized MPEG Filesystem (OMFS)
+
+Overview
+========
+
+OMFS is a filesystem created by SonicBlue for use in the ReplayTV DVR
+and Rio Karma MP3 player.  The filesystem is extent-based, utilizing
+block sizes from 2k to 8k, with hash-based directories.  This
+filesystem driver may be used to read and write disks from these
+devices.
+
+Note, it is not recommended that this FS be used in place of a general
+filesystem for your own streaming media device.  Native Linux filesystems
+will likely perform better.
+
+More information is available at:
+
+    http://linux-karma.sf.net/
+
+Various utilities, including mkomfs and omfsck, are included with
+omfsprogs, available at:
+
+    http://bobcopeland.com/karma/
+
+Instructions are included in its README.
+
+Options
+=======
+
+OMFS supports the following mount-time options:
+
+    uid=n        - make all files owned by specified user
+    gid=n        - make all files owned by specified group
+    umask=xxx    - set permission umask to xxx
+    fmask=xxx    - set umask to xxx for files
+    dmask=xxx    - set umask to xxx for directories
+
+Disk format
+===========
+
+OMFS discriminates between "sysblocks" and normal data blocks.  The sysblock
+group consists of super block information, file metadata, directory structures,
+and extents.  Each sysblock has a header containing CRCs of the entire
+sysblock, and may be mirrored in successive blocks on the disk.  A sysblock may
+have a smaller size than a data block, but since they are both addressed by the
+same 64-bit block number, any remaining space in the smaller sysblock is
+unused.
+
+Sysblock header information:
+
+struct omfs_header {
+        __be64 h_self;                  /* FS block where this is located */
+        __be32 h_body_size;             /* size of useful data after header */
+        __be16 h_crc;                   /* crc-ccitt of body_size bytes */
+        char h_fill1[2];
+        u8 h_version;                   /* version, always 1 */
+        char h_type;                    /* OMFS_INODE_X */
+        u8 h_magic;                     /* OMFS_IMAGIC */
+        u8 h_check_xor;                 /* XOR of header bytes before this */
+        __be32 h_fill2;
+};
+
+Files and directories are both represented by omfs_inode:
+
+struct omfs_inode {
+        struct omfs_header i_head;      /* header */
+        __be64 i_parent;                /* parent containing this inode */
+        __be64 i_sibling;               /* next inode in hash bucket */
+        __be64 i_ctime;                 /* ctime, in milliseconds */
+        char i_fill1[35];
+        char i_type;                    /* OMFS_[DIR,FILE] */
+        __be32 i_fill2;
+        char i_fill3[64];
+        char i_name[OMFS_NAMELEN];      /* filename */
+        __be64 i_size;                  /* size of file, in bytes */
+};
+
+Directories in OMFS are implemented as a large hash table.  Filenames are
+hashed then prepended into the bucket list beginning at OMFS_DIR_START.
+Lookup requires hashing the filename, then seeking across i_sibling pointers
+until a match is found on i_name.  Empty buckets are represented by block
+pointers with all-1s (~0).
+
+A file is an omfs_inode structure followed by an extent table beginning at
+OMFS_EXTENT_START:
+
+struct omfs_extent_entry {
+        __be64 e_cluster;               /* start location of a set of blocks */
+        __be64 e_blocks;                /* number of blocks after e_cluster */
+};
+
+struct omfs_extent {
+        __be64 e_next;                  /* next extent table location */
+        __be32 e_extent_count;          /* total # extents in this table */
+        __be32 e_fill;
+        struct omfs_extent_entry e_entry;       /* start of extent entries */
+};
+
+Each extent holds the block offset followed by number of blocks allocated to
+the extent.  The final extent in each table is a terminator with e_cluster
+being ~0 and e_blocks being ones'-complement of the total number of blocks
+in the table.
+
+If this table overflows, a continuation inode is written and pointed to by
+e_next.  These have a header but lack the rest of the inode structure.
+

Documentation/filesystems/proc.txt

@@ -296,6 +296,7 @@ Table 1-4: Kernel info in /proc
  uptime      System uptime                                     
  version     Kernel version                                    
  video	     bttv info of video resources			(2.4)
+ vmallocinfo Show vmalloced areas
 ..............................................................................
 
 You can,  for  example,  check  which interrupts are currently in use and what
@@ -557,6 +558,49 @@ VmallocTotal: total size of vmalloc memory area
  VmallocUsed: amount of vmalloc area which is used
 VmallocChunk: largest contigious block of vmalloc area which is free
 
+..............................................................................
+
+vmallocinfo:
+
+Provides information about vmalloced/vmaped areas. One line per area,
+containing the virtual address range of the area, size in bytes,
+caller information of the creator, and optional information depending
+on the kind of area :
+
+ pages=nr    number of pages
+ phys=addr   if a physical address was specified
+ ioremap     I/O mapping (ioremap() and friends)
+ vmalloc     vmalloc() area
+ vmap        vmap()ed pages
+ user        VM_USERMAP area
+ vpages      buffer for pages pointers was vmalloced (huge area)
+ N<node>=nr  (Only on NUMA kernels)
+             Number of pages allocated on memory node <node>
+
+> cat /proc/vmallocinfo
+0xffffc20000000000-0xffffc20000201000 2101248 alloc_large_system_hash+0x204 ...
+  /0x2c0 pages=512 vmalloc N0=128 N1=128 N2=128 N3=128
+0xffffc20000201000-0xffffc20000302000 1052672 alloc_large_system_hash+0x204 ...
+  /0x2c0 pages=256 vmalloc N0=64 N1=64 N2=64 N3=64
+0xffffc20000302000-0xffffc20000304000    8192 acpi_tb_verify_table+0x21/0x4f...
+  phys=7fee8000 ioremap
+0xffffc20000304000-0xffffc20000307000   12288 acpi_tb_verify_table+0x21/0x4f...
+  phys=7fee7000 ioremap
+0xffffc2000031d000-0xffffc2000031f000    8192 init_vdso_vars+0x112/0x210
+0xffffc2000031f000-0xffffc2000032b000   49152 cramfs_uncompress_init+0x2e ...
+  /0x80 pages=11 vmalloc N0=3 N1=3 N2=2 N3=3
+0xffffc2000033a000-0xffffc2000033d000   12288 sys_swapon+0x640/0xac0      ...
+  pages=2 vmalloc N1=2
+0xffffc20000347000-0xffffc2000034c000   20480 xt_alloc_table_info+0xfe ...
+  /0x130 [x_tables] pages=4 vmalloc N0=4
+0xffffffffa0000000-0xffffffffa000f000   61440 sys_init_module+0xc27/0x1d00 ...
+   pages=14 vmalloc N2=14
+0xffffffffa000f000-0xffffffffa0014000   20480 sys_init_module+0xc27/0x1d00 ...
+   pages=4 vmalloc N1=4
+0xffffffffa0014000-0xffffffffa0017000   12288 sys_init_module+0xc27/0x1d00 ...
+   pages=2 vmalloc N1=2
+0xffffffffa0017000-0xffffffffa0022000   45056 sys_init_module+0xc27/0x1d00 ...
+   pages=10 vmalloc N0=10
 
 1.3 IDE devices in /proc/ide
 ----------------------------
@@ -887,7 +931,7 @@ group_prealloc  max_to_scan  mb_groups  mb_history  min_to_scan  order2_req
 stats  stream_req
 
 mb_groups:
-This file gives the details of mutiblock allocator buddy cache of free blocks
+This file gives the details of multiblock allocator buddy cache of free blocks
 
 mb_history:
 Multiblock allocation history.
@@ -1430,7 +1474,7 @@ used because pages_free(1355) is smaller than watermark + protection[2]
 normal page requirement. If requirement is DMA zone(index=0), protection[0]
 (=0) is used.
 
-zone[i]'s protection[j] is calculated by following exprssion.
+zone[i]'s protection[j] is calculated by following expression.
 
 (i < j):
   zone[i]->protection[j]

Documentation/filesystems/relay.txt

@@ -294,6 +294,16 @@ user-defined data with a channel, and is immediately available
 (including in create_buf_file()) via chan->private_data or
 buf->chan->private_data.
 
+Buffer-only channels
+--------------------
+
+These channels have no files associated and can be created with
+relay_open(NULL, NULL, ...). Such channels are useful in scenarios such
+as when doing early tracing in the kernel, before the VFS is up. In these
+cases, one may open a buffer-only channel and then call
+relay_late_setup_files() when the kernel is ready to handle files,
+to expose the buffered data to the userspace.
+
 Channel 'modes'
 ---------------
 

Documentation/filesystems/sysfs.txt

@@ -248,6 +248,7 @@ The top level sysfs directory looks like:
 block/
 bus/
 class/
+dev/
 devices/
 firmware/
 net/
@@ -274,6 +275,11 @@ fs/ contains a directory for some filesystems.  Currently each
 filesystem wanting to export attributes must create its own hierarchy
 below fs/ (see ./fuse.txt for an example).
 
+dev/ contains two directories char/ and block/. Inside these two
+directories there are symlinks named <major>:<minor>.  These symlinks
+point to the sysfs directory for the given device.  /sys/dev provides a
+quick way to lookup the sysfs interface for a device from the result of
+a stat(2) operation.
 
 More information can driver-model specific features can be found in
 Documentation/driver-model/. 

Documentation/filesystems/ubifs.txt

+Introduction
+=============
+
+UBIFS file-system stands for UBI File System. UBI stands for "Unsorted
+Block Images". UBIFS is a flash file system, which means it is designed
+to work with flash devices. It is important to understand, that UBIFS
+is completely different to any traditional file-system in Linux, like
+Ext2, XFS, JFS, etc. UBIFS represents a separate class of file-systems
+which work with MTD devices, not block devices. The other Linux
+file-system of this class is JFFS2.
+
+To make it more clear, here is a small comparison of MTD devices and
+block devices.
+
+1 MTD devices represent flash devices and they consist of eraseblocks of
+  rather large size, typically about 128KiB. Block devices consist of
+  small blocks, typically 512 bytes.
+2 MTD devices support 3 main operations - read from some offset within an
+  eraseblock, write to some offset within an eraseblock, and erase a whole
+  eraseblock. Block  devices support 2 main operations - read a whole
+  block and write a whole block.
+3 The whole eraseblock has to be erased before it becomes possible to
+  re-write its contents. Blocks may be just re-written.
+4 Eraseblocks become worn out after some number of erase cycles -
+  typically 100K-1G for SLC NAND and NOR flashes, and 1K-10K for MLC
+  NAND flashes. Blocks do not have the wear-out property.
+5 Eraseblocks may become bad (only on NAND flashes) and software should
+  deal with this. Blocks on hard drives typically do not become bad,
+  because hardware has mechanisms to substitute bad blocks, at least in
+  modern LBA disks.
+
+It should be quite obvious why UBIFS is very different to traditional
+file-systems.
+
+UBIFS works on top of UBI. UBI is a separate software layer which may be
+found in drivers/mtd/ubi. UBI is basically a volume management and
+wear-leveling layer. It provides so called UBI volumes which is a higher
+level abstraction than a MTD device. The programming model of UBI devices
+is very similar to MTD devices - they still consist of large eraseblocks,
+they have read/write/erase operations, but UBI devices are devoid of
+limitations like wear and bad blocks (items 4 and 5 in the above list).
+
+In a sense, UBIFS is a next generation of JFFS2 file-system, but it is
+very different and incompatible to JFFS2. The following are the main
+differences.
+
+* JFFS2 works on top of MTD devices, UBIFS depends on UBI and works on
+  top of UBI volumes.
+* JFFS2 does not have on-media index and has to build it while mounting,
+  which requires full media scan. UBIFS maintains the FS indexing
+  information on the flash media and does not require full media scan,
+  so it mounts many times faster than JFFS2.
+* JFFS2 is a write-through file-system, while UBIFS supports write-back,
+  which makes UBIFS much faster on writes.
+
+Similarly to JFFS2, UBIFS supports on-the-flight compression which makes
+it possible to fit quite a lot of data to the flash.
+
+Similarly to JFFS2, UBIFS is tolerant of unclean reboots and power-cuts.
+It does not need stuff like ckfs.ext2. UBIFS automatically replays its
+journal and recovers from crashes, ensuring that the on-flash data
+structures are consistent.
+
+UBIFS scales logarithmically (most of the data structures it uses are
+trees), so the mount time and memory consumption do not linearly depend
+on the flash size, like in case of JFFS2. This is because UBIFS
+maintains the FS index on the flash media. However, UBIFS depends on
+UBI, which scales linearly. So overall UBI/UBIFS stack scales linearly.
+Nevertheless, UBI/UBIFS scales considerably better than JFFS2.
+
+The authors of UBIFS believe, that it is possible to develop UBI2 which
+would scale logarithmically as well. UBI2 would support the same API as UBI,
+but it would be binary incompatible to UBI. So UBIFS would not need to be
+changed to use UBI2
+
+
+Mount options
+=============
+
+(*) == default.
+
+norm_unmount (*)	commit on unmount; the journal is committed
+			when the file-system is unmounted so that the
+			next mount does not have to replay the journal
+			and it becomes very fast;
+fast_unmount		do not commit on unmount; this option makes
+			unmount faster, but the next mount slower
+			because of the need to replay the journal.
+
+
+Quick usage instructions
+========================
+
+The UBI volume to mount is specified using "ubiX_Y" or "ubiX:NAME" syntax,
+where "X" is UBI device number, "Y" is UBI volume number, and "NAME" is
+UBI volume name.
+
+Mount volume 0 on UBI device 0 to /mnt/ubifs:
+$ mount -t ubifs ubi0_0 /mnt/ubifs
+
+Mount "rootfs" volume of UBI device 0 to /mnt/ubifs ("rootfs" is volume
+name):
+$ mount -t ubifs ubi0:rootfs /mnt/ubifs
+
+The following is an example of the kernel boot arguments to attach mtd0
+to UBI and mount volume "rootfs":
+ubi.mtd=0 root=ubi0:rootfs rootfstype=ubifs
+
+
+Module Parameters for Debugging
+===============================
+
+When UBIFS has been compiled with debugging enabled, there are 3 module
+parameters that are available to control aspects of testing and debugging.
+The parameters are unsigned integers where each bit controls an option.
+The parameters are:
+
+debug_msgs	Selects which debug messages to display, as follows:
+
+		Message Type				Flag value
+
+		General messages			1
+		Journal messages			2
+		Mount messages				4
+		Commit messages				8
+		LEB search messages			16
+		Budgeting messages			32
+		Garbage collection messages		64
+		Tree Node Cache (TNC) messages		128
+		LEB properties (lprops) messages	256
+		Input/output messages			512
+		Log messages				1024
+		Scan messages				2048
+		Recovery messages			4096
+
+debug_chks	Selects extra checks that UBIFS can do while running:
+
+		Check					Flag value
+
+		General checks				1
+		Check Tree Node Cache (TNC)		2
+		Check indexing tree size		4
+		Check orphan area			8
+		Check old indexing tree			16
+		Check LEB properties (lprops)		32
+		Check leaf nodes and inodes		64
+
+debug_tsts	Selects a mode of testing, as follows:
+
+		Test mode				Flag value
+
+		Force in-the-gaps method		2
+		Failure mode for recovery testing	4
+
+For example, set debug_msgs to 5 to display General messages and Mount
+messages.
+
+
+References
+==========
+
+UBIFS documentation and FAQ/HOWTO at the MTD web site:
+http://www.linux-mtd.infradead.org/doc/ubifs.html
+http://www.linux-mtd.infradead.org/faq/ubifs.html

Documentation/filesystems/vfat.txt

@@ -96,6 +96,14 @@ shortname=lower|win95|winnt|mixed
 			emulate the Windows 95 rule for create.
 		 Default setting is `lower'.
 
+tz=UTC        -- Interpret timestamps as UTC rather than local time.
+                 This option disables the conversion of timestamps
+                 between local time (as used by Windows on FAT) and UTC
+                 (which Linux uses internally).  This is particuluarly
+                 useful when mounting devices (like digital cameras)
+                 that are set to UTC in order to avoid the pitfalls of
+                 local time.
+
 <bool>: 0,1,yes,no,true,false
 
 TODO

Documentation/filesystems/vfs.txt

@@ -143,7 +143,7 @@ struct file_system_type {
 
 The get_sb() method has the following arguments:
 
-  struct file_system_type *fs_type: decribes the filesystem, partly initialized
+  struct file_system_type *fs_type: describes the filesystem, partly initialized
   	by the specific filesystem code
 
   int flags: mount flags
@@ -895,9 +895,9 @@ struct dentry_operations {
 	iput() yourself
 
   d_dname: called when the pathname of a dentry should be generated.
-	Usefull for some pseudo filesystems (sockfs, pipefs, ...) to delay
+	Useful for some pseudo filesystems (sockfs, pipefs, ...) to delay
 	pathname generation. (Instead of doing it when dentry is created,
-	its done only when the path is needed.). Real filesystems probably
+	it's done only when the path is needed.). Real filesystems probably
 	dont want to use it, because their dentries are present in global
 	dcache hash, so their hash should be an invariant. As no lock is
 	held, d_dname() should not try to modify the dentry itself, unless

Documentation/gpio.txt

@@ -347,15 +347,12 @@ necessarily be nonportable.
 Dynamic definition of GPIOs is not currently standard; for example, as
 a side effect of configuring an add-on board with some GPIO expanders.
 
-These calls are purely for kernel space, but a userspace API could be built
-on top of them.
-
 
 GPIO implementor's framework (OPTIONAL)
 =======================================
 As noted earlier, there is an optional implementation framework making it
 easier for platforms to support different kinds of GPIO controller using
-the same programming interface.
+the same programming interface.  This framework is called "gpiolib".
 
 As a debugging aid, if debugfs is available a /sys/kernel/debug/gpio file
 will be found there.  That will list all the controllers registered through
@@ -392,11 +389,21 @@ either NULL or the label associated with that GPIO when it was requested.
 
 Platform Support
 ----------------
-To support this framework, a platform's Kconfig will "select HAVE_GPIO_LIB"
+To support this framework, a platform's Kconfig will "select" either
+ARCH_REQUIRE_GPIOLIB or ARCH_WANT_OPTIONAL_GPIOLIB
 and arrange that its <asm/gpio.h> includes <asm-generic/gpio.h> and defines
 three functions: gpio_get_value(), gpio_set_value(), and gpio_cansleep().
 They may also want to provide a custom value for ARCH_NR_GPIOS.
 
+ARCH_REQUIRE_GPIOLIB means that the gpio-lib code will always get compiled
+into the kernel on that architecture.
+
+ARCH_WANT_OPTIONAL_GPIOLIB means the gpio-lib code defaults to off and the user
+can enable it and build it into the kernel optionally.
+
+If neither of these options are selected, the platform does not support
+GPIOs through GPIO-lib and the code cannot be enabled by the user.
+
 Trivial implementations of those functions can directly use framework
 code, which always dispatches through the gpio_chip:
 
@@ -439,4 +446,120 @@ becomes available.  That may mean the device should not be registered until
 calls for that GPIO can work.  One way to address such dependencies is for
 such gpio_chip controllers to provide setup() and teardown() callbacks to
 board specific code; those board specific callbacks would register devices
-once all the necessary resources are available.
+once all the necessary resources are available, and remove them later when
+the GPIO controller device becomes unavailable.
+
+
+Sysfs Interface for Userspace (OPTIONAL)
+========================================
+Platforms which use the "gpiolib" implementors framework may choose to
+configure a sysfs user interface to GPIOs.  This is different from the
+debugfs interface, since it provides control over GPIO direction and
+value instead of just showing a gpio state summary.  Plus, it could be
+present on production systems without debugging support.
+
+Given approprate hardware documentation for the system, userspace could
+know for example that GPIO #23 controls the write protect line used to
+protect boot loader segments in flash memory.  System upgrade procedures
+may need to temporarily remove that protection, first importing a GPIO,
+then changing its output state, then updating the code before re-enabling
+the write protection.  In normal use, GPIO #23 would never be touched,
+and the kernel would have no need to know about it.
+
+Again depending on appropriate hardware documentation, on some systems
+userspace GPIO can be used to determine system configuration data that
+standard kernels won't know about.  And for some tasks, simple userspace
+GPIO drivers could be all that the system really needs.
+
+Note that standard kernel drivers exist for common "LEDs and Buttons"
+GPIO tasks:  "leds-gpio" and "gpio_keys", respectively.  Use those
+instead of talking directly to the GPIOs; they integrate with kernel
+frameworks better than your userspace code could.
+
+
+Paths in Sysfs
+--------------
+There are three kinds of entry in /sys/class/gpio:
+
+   -	Control interfaces used to get userspace control over GPIOs;
+
+   -	GPIOs themselves; and
+
+   -	GPIO controllers ("gpio_chip" instances).
+
+That's in addition to standard files including the "device" symlink.
+
+The control interfaces are write-only:
+
+    /sys/class/gpio/
+
+    	"export" ... Userspace may ask the kernel to export control of
+		a GPIO to userspace by writing its number to this file.
+
+		Example:  "echo 19 > export" will create a "gpio19" node
+		for GPIO #19, if that's not requested by kernel code.
+
+    	"unexport" ... Reverses the effect of exporting to userspace.
+
+		Example:  "echo 19 > unexport" will remove a "gpio19"
+		node exported using the "export" file.
+
+GPIO signals have paths like /sys/class/gpio/gpio42/ (for GPIO #42)
+and have the following read/write attributes:
+
+    /sys/class/gpio/gpioN/
+
+	"direction" ... reads as either "in" or "out".  This value may
+		normally be written.  Writing as "out" defaults to
+		initializing the value as low.  To ensure glitch free
+		operation, values "low" and "high" may be written to
+		configure the GPIO as an output with that initial value.
+
+		Note that this attribute *will not exist* if the kernel
+		doesn't support changing the direction of a GPIO, or
+		it was exported by kernel code that didn't explicitly
+		allow userspace to reconfigure this GPIO's direction.
+
+	"value" ... reads as either 0 (low) or 1 (high).  If the GPIO
+		is configured as an output, this value may be written;
+		any nonzero value is treated as high.
+
+GPIO controllers have paths like /sys/class/gpio/chipchip42/ (for the
+controller implementing GPIOs starting at #42) and have the following
+read-only attributes:
+
+    /sys/class/gpio/gpiochipN/
+
+    	"base" ... same as N, the first GPIO managed by this chip
+
+    	"label" ... provided for diagnostics (not always unique)
+
+    	"ngpio" ... how many GPIOs this manges (N to N + ngpio - 1)
+
+Board documentation should in most cases cover what GPIOs are used for
+what purposes.  However, those numbers are not always stable; GPIOs on
+a daughtercard might be different depending on the base board being used,
+or other cards in the stack.  In such cases, you may need to use the
+gpiochip nodes (possibly in conjunction with schematics) to determine
+the correct GPIO number to use for a given signal.
+
+
+Exporting from Kernel code
+--------------------------
+Kernel code can explicitly manage exports of GPIOs which have already been
+requested using gpio_request():
+
+	/* export the GPIO to userspace */
+	int gpio_export(unsigned gpio, bool direction_may_change);
+
+	/* reverse gpio_export() */
+	void gpio_unexport();
+
+After a kernel driver requests a GPIO, it may only be made available in
+the sysfs interface by gpio_export().  The driver can control whether the
+signal direction may change.  This helps drivers prevent userspace code
+from accidentally clobbering important system state.
+
+This explicit exporting can help with debugging (by making some kinds
+of experiments easier), or can provide an always-there interface that's
+suitable for documenting as part of a board support package.

Documentation/hwmon/dme1737

@@ -22,6 +22,10 @@ Module Parameters
 			and PWM output control functions. Using this parameter
 			shouldn't be required since the BIOS usually takes care
 			of this.
+* probe_all_addr: bool	Include non-standard LPC addresses 0x162e and 0x164e
+			when probing for ISA devices. This is required for the
+			following boards:
+			- VIA EPIA SN18000
 
 Note that there is no need to use this parameter if the driver loads without
 complaining. The driver will say so if it is necessary.

Documentation/hwmon/lm85

@@ -96,11 +96,6 @@ initial testing of the ADM1027 it was 1.00 degC steps. Analog Devices has
 confirmed this "bug". The ADT7463 is reported to work as described in the
 documentation. The current lm85 driver does not show the offset register.
 
-The ADT7463 has a THERM asserted counter. This counter has a 22.76ms
-resolution and a range of 5.8 seconds. The driver implements a 32-bit
-accumulator of the counter value to extend the range to over a year. The
-counter will stay at it's max value until read.
-
 See the vendor datasheets for more information. There is application note
 from National (AN-1260) with some additional information about the LM85.
 The Analog Devices datasheet is very detailed and describes a procedure for
@@ -206,13 +201,15 @@ Configuration choices:
 
 The National LM85's have two vendor specific configuration
 features. Tach. mode and Spinup Control. For more details on these,
-see the LM85 datasheet or Application Note AN-1260.
+see the LM85 datasheet or Application Note AN-1260. These features
+are not currently supported by the lm85 driver.
 
 The Analog Devices ADM1027 has several vendor specific enhancements.
 The number of pulses-per-rev of the fans can be set, Tach monitoring
 can be optimized for PWM operation, and an offset can be applied to
 the temperatures to compensate for systemic errors in the
-measurements.
+measurements. These features are not currently supported by the lm85
+driver.
 
 In addition to the ADM1027 features, the ADT7463 also has Tmin control
 and THERM asserted counts. Automatic Tmin control acts to adjust the

Documentation/i2c/chips/max6875

@@ -49,7 +49,7 @@ $ modprobe max6875 force=0,0x50
 
 The MAX6874/MAX6875 ignores address bit 0, so this driver attaches to multiple
 addresses.  For example, for address 0x50, it also reserves 0x51.
-The even-address instance is called 'max6875', the odd one is 'max6875 subclient'.
+The even-address instance is called 'max6875', the odd one is 'dummy'.
 
 
 Programming the chip using i2c-dev

Documentation/i2c/chips/pca9539

@@ -7,7 +7,7 @@ drivers/gpio/pca9539.c instead.
 Supported chips:
   * Philips PCA9539
     Prefix: 'pca9539'
-    Addresses scanned: 0x74 - 0x77
+    Addresses scanned: none
     Datasheet:
         http://www.semiconductors.philips.com/acrobat/datasheets/PCA9539_2.pdf
 
@@ -23,6 +23,14 @@ The input sense can also be inverted.
 The 16 lines are split between two bytes.
 
 
+Detection
+---------
+
+The PCA9539 is difficult to detect and not commonly found in PC machines,
+so you have to pass the I2C bus and address of the installed PCA9539
+devices explicitly to the driver at load time via the force=... parameter.
+
+
 Sysfs entries
 -------------
 

Documentation/i2c/chips/pcf8574

@@ -4,13 +4,13 @@ Kernel driver pcf8574
 Supported chips:
   * Philips PCF8574
     Prefix: 'pcf8574'
-    Addresses scanned: I2C 0x20 - 0x27
+    Addresses scanned: none
     Datasheet: Publicly available at the Philips Semiconductors website
                http://www.semiconductors.philips.com/pip/PCF8574P.html
 
  * Philips PCF8574A
     Prefix: 'pcf8574a'
-    Addresses scanned: I2C 0x38 - 0x3f
+    Addresses scanned: none
     Datasheet: Publicly available at the Philips Semiconductors website
                http://www.semiconductors.philips.com/pip/PCF8574P.html
 
@@ -38,12 +38,10 @@ For more informations see the datasheet.
 Accessing PCF8574(A) via /sys interface
 -------------------------------------
 
-! Be careful !
 The PCF8574(A) is plainly impossible to detect ! Stupid chip.
-So every chip with address in the interval [20..27] and [38..3f] are
-detected as PCF8574(A). If you have other chips in this address
-range, the workaround is to load this module after the one
-for your others chips.
+So, you have to pass the I2C bus and address of the installed PCF857A
+and PCF8574A devices explicitly to the driver at load time via the
+force=... parameter.
 
 On detection (i.e. insmod, modprobe et al.), directories are being
 created for each detected PCF8574(A):

Documentation/i2c/chips/pcf8575

@@ -40,12 +40,9 @@ Detection
 ---------
 
 There is no method known to detect whether a chip on a given I2C address is
-a PCF8575 or whether it is any other I2C device. So there are two alternatives
-to let the driver find the installed PCF8575 devices:
-- Load this driver after any other I2C driver for I2C devices with addresses
-  in the range 0x20 .. 0x27.
-- Pass the I2C bus and address of the installed PCF8575 devices explicitly to
-  the driver at load time via the probe=... or force=... parameters.
+a PCF8575 or whether it is any other I2C device, so you have to pass the I2C
+bus and address of the installed PCF8575 devices explicitly to the driver at
+load time via the force=... parameter.
 
 /sys interface
 --------------

Documentation/ia64/kvm.txt

@@ -50,9 +50,9 @@ Note: For step 2, please make sure that host page size == TARGET_PAGE_SIZE of qe
 		/usr/local/bin/qemu-system-ia64 -smp xx -m 512 -hda $your_image
 		(xx is the number of virtual processors for the guest, now the maximum value is 4)
 
-5. Known possibile issue on some platforms with old Firmware.
+5. Known possible issue on some platforms with old Firmware.
 
-If meet strange host crashe issues, try to solve it through either of the following ways:
+In the event of strange host crash issues, try to solve it through either of the following ways:
 
 (1): Upgrade your Firmware to the latest one.
 
@@ -65,8 +65,8 @@ index 0b53344..f02b0f7 100644
 	mov ar.pfs = loc1
 	mov rp = loc0
 	;;
--	srlz.d				// seralize restoration of psr.l
-+	srlz.i			// seralize restoration of psr.l
+-	srlz.d				// serialize restoration of psr.l
++	srlz.i			// serialize restoration of psr.l
 +	;;
 	br.ret.sptk.many b0
  END(ia64_pal_call_static)

Documentation/ia64/paravirt_ops.txt

+Paravirt_ops on IA64
+====================
+                          21 May 2008, Isaku Yamahata <yamahata@valinux.co.jp>
+
+
+Introduction
+------------
+The aim of this documentation is to help with maintainability and/or to
+encourage people to use paravirt_ops/IA64.
+
+paravirt_ops (pv_ops in short) is a way for virtualization support of
+Linux kernel on x86. Several ways for virtualization support were
+proposed, paravirt_ops is the winner.
+On the other hand, now there are also several IA64 virtualization
+technologies like kvm/IA64, xen/IA64 and many other academic IA64
+hypervisors so that it is good to add generic virtualization
+infrastructure on Linux/IA64.
+
+
+What is paravirt_ops?
+---------------------
+It has been developed on x86 as virtualization support via API, not ABI.
+It allows each hypervisor to override operations which are important for
+hypervisors at API level. And it allows a single kernel binary to run on
+all supported execution environments including native machine.
+Essentially paravirt_ops is a set of function pointers which represent
+operations corresponding to low level sensitive instructions and high
+level functionalities in various area. But one significant difference
+from usual function pointer table is that it allows optimization with
+binary patch. It is because some of these operations are very
+performance sensitive and indirect call overhead is not negligible.
+With binary patch, indirect C function call can be transformed into
+direct C function call or in-place execution to eliminate the overhead.
+
+Thus, operations of paravirt_ops are classified into three categories.
+- simple indirect call
+  These operations correspond to high level functionality so that the
+  overhead of indirect call isn't very important.
+
+- indirect call which allows optimization with binary patch
+  Usually these operations correspond to low level instructions. They
+  are called frequently and performance critical. So the overhead is
+  very important.
+
+- a set of macros for hand written assembly code
+  Hand written assembly codes (.S files) also need paravirtualization
+  because they include sensitive instructions or some of code paths in
+  them are very performance critical.
+
+
+The relation to the IA64 machine vector
+---------------------------------------
+Linux/IA64 has the IA64 machine vector functionality which allows the
+kernel to switch implementations (e.g. initialization, ipi, dma api...)
+depending on executing platform.
+We can replace some implementations very easily defining a new machine
+vector. Thus another approach for virtualization support would be
+enhancing the machine vector functionality.
+But paravirt_ops approach was taken because
+- virtualization support needs wider support than machine vector does.
+  e.g. low level instruction paravirtualization. It must be
+       initialized very early before platform detection.
+
+- virtualization support needs more functionality like binary patch.
+  Probably the calling overhead might not be very large compared to the
+  emulation overhead of virtualization. However in the native case, the
+  overhead should be eliminated completely.
+  A single kernel binary should run on each environment including native,
+  and the overhead of paravirt_ops on native environment should be as
+  small as possible.
+
+- for full virtualization technology, e.g. KVM/IA64 or
+  Xen/IA64 HVM domain, the result would be
+  (the emulated platform machine vector. probably dig) + (pv_ops).
+  This means that the virtualization support layer should be under
+  the machine vector layer.
+
+Possibly it might be better to move some function pointers from
+paravirt_ops to machine vector. In fact, Xen domU case utilizes both
+pv_ops and machine vector.
+
+
+IA64 paravirt_ops
+-----------------
+In this section, the concrete paravirt_ops will be discussed.
+Because of the architecture difference between ia64 and x86, the
+resulting set of functions is very different from x86 pv_ops.
+
+- C function pointer tables
+They are not very performance critical so that simple C indirect
+function call is acceptable. The following structures are defined at
+this moment. For details see linux/include/asm-ia64/paravirt.h
+  - struct pv_info
+    This structure describes the execution environment.
+  - struct pv_init_ops
+    This structure describes the various initialization hooks.
+  - struct pv_iosapic_ops
+    This structure describes hooks to iosapic operations.
+  - struct pv_irq_ops
+    This structure describes hooks to irq related operations
+  - struct pv_time_op
+    This structure describes hooks to steal time accounting.
+
+- a set of indirect calls which need optimization
+Currently this class of functions correspond to a subset of IA64
+intrinsics. At this moment the optimization with binary patch isn't
+implemented yet.
+struct pv_cpu_op is defined. For details see
+linux/include/asm-ia64/paravirt_privop.h
+Mostly they correspond to ia64 intrinsics 1-to-1.
+Caveat: Now they are defined as C indirect function pointers, but in
+order to support binary patch optimization, they will be changed
+using GCC extended inline assembly code.
+
+- a set of macros for hand written assembly code (.S files)
+For maintenance purpose, the taken approach for .S files is single
+source code and compile multiple times with different macros definitions.
+Each pv_ops instance must define those macros to compile.
+The important thing here is that sensitive, but non-privileged
+instructions must be paravirtualized and that some privileged
+instructions also need paravirtualization for reasonable performance.
+Developers who modify .S files must be aware of that. At this moment
+an easy checker is implemented to detect paravirtualization breakage.
+But it doesn't cover all the cases.
+
+Sometimes this set of macros is called pv_cpu_asm_op. But there is no
+corresponding structure in the source code.
+Those macros mostly 1:1 correspond to a subset of privileged
+instructions. See linux/include/asm-ia64/native/inst.h.
+And some functions written in assembly also need to be overrided so
+that each pv_ops instance have to define some macros. Again see
+linux/include/asm-ia64/native/inst.h.
+
+
+Those structures must be initialized very early before start_kernel.
+Probably initialized in head.S using multi entry point or some other trick.
+For native case implementation see linux/arch/ia64/kernel/paravirt.c.

Documentation/input/cs461x.txt

@@ -31,7 +31,7 @@ The driver works with ALSA drivers simultaneously. For example, the xracer
 uses joystick as input device and PCM device as sound output in one time.
 There are no sound or input collisions detected. The source code have
 comments about them; but I've found the joystick can be initialized 
-separately of ALSA modules. So, you canm use only one joystick driver
+separately of ALSA modules. So, you can use only one joystick driver
 without ALSA drivers. The ALSA drivers are not needed to compile or
 run this driver.
 

Documentation/input/gameport-programming.txt

-$Id: gameport-programming.txt,v 1.3 2001/04/24 13:51:37 vojtech Exp $
-
 Programming gameport drivers
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

Documentation/isdn/README.mISDN

+mISDN is a new modular ISDN driver, in the long term it should replace
+the old I4L driver architecture for passiv ISDN cards.
+It was designed to allow a broad range of applications and interfaces
+but only have the basic function in kernel, the interface to the user
+space is based on sockets with a own address family AF_ISDN.
+