6 files changed, 171 insertions, 0 deletions
diff --git a/Documentation/ABI/README b/Documentation/ABI/README
new file mode 100644
index 000000000000..9feaf16f1617
--- /dev/null
+++ b/Documentation/ABI/README
@@ -0,0 +1,77 @@
+This directory attempts to document the ABI between the Linux kernel and
+userspace, and the relative stability of these interfaces.  Due to the
+everchanging nature of Linux, and the differing maturity levels, these
+interfaces should be used by userspace programs in different ways.
+We have four different levels of ABI stability, as shown by the four
+different subdirectories in this location.  Interfaces may change levels
+of stability according to the rules described below.
+The different levels of stability are:
+  stable/
+        This directory documents the interfaces that the developer has
+        defined to be stable.  Userspace programs are free to use these
+        interfaces with no restrictions, and backward compatibility for
+        them will be guaranteed for at least 2 years.  Most interfaces
+        (like syscalls) are expected to never change and always be
+        available.
+  testing/
+        This directory documents interfaces that are felt to be stable,
+        as the main development of this interface has been completed.
+        The interface can be changed to add new features, but the
+        current interface will not break by doing this, unless grave
+        errors or security problems are found in them.  Userspace
+        programs can start to rely on these interfaces, but they must be
+        aware of changes that can occur before these interfaces move to
+        be marked stable.  Programs that use these interfaces are
+        strongly encouraged to add their name to the description of
+        these interfaces, so that the kernel developers can easily
+        notify them if any changes occur (see the description of the
+        layout of the files below for details on how to do this.)
+  obsolete/
+        This directory documents interfaces that are still remaining in
+        the kernel, but are marked to be removed at some later point in
+        time.  The description of the interface will document the reason
+        why it is obsolete and when it can be expected to be removed.
+        The file Documentation/feature-removal-schedule.txt may describe
+        some of these interfaces, giving a schedule for when they will
+        be removed.
+  removed/
+        This directory contains a list of the old interfaces that have
+        been removed from the kernel.
+Every file in these directories will contain the following information:
+What:           Short description of the interface
+Date:           Date created
+KernelVersion:  Kernel version this feature first showed up in.
+Contact:        Primary contact for this interface (may be a mailing list)
+Description:    Long description of the interface and how to use it.
+Users:          All users of this interface who wish to be notified when
+                it changes.  This is very important for interfaces in
+                the "testing" stage, so that kernel developers can work
+                with userspace developers to ensure that things do not
+                break in ways that are unacceptable.  It is also
+                important to get feedback for these interfaces to make
+                sure they are working in a proper way and do not need to
+                be changed further.
+How things move between levels:
+Interfaces in stable may move to obsolete, as long as the proper
+notification is given.
+Interfaces may be removed from obsolete and the kernel as long as the
+documented amount of time has gone by.
+Interfaces in the testing state can move to the stable state when the
+developers feel they are finished.  They cannot be removed from the
+kernel tree without going through the obsolete state first.
+It's up to the developer to place their interfaces in the category they
+wish for it to start out in.
diff --git a/Documentation/ABI/obsolete/devfs b/Documentation/ABI/obsolete/devfs
new file mode 100644
index 000000000000..b8b87399bc8f
--- /dev/null
+++ b/Documentation/ABI/obsolete/devfs
@@ -0,0 +1,13 @@
+What:           devfs
+Date:           July 2005
+Contact:        Greg Kroah-Hartman <gregkh@suse.de>
+Description:
+        devfs has been unmaintained for a number of years, has unfixable
+        races, contains a naming policy within the kernel that is
+        against the LSB, and can be replaced by using udev.
+        The files fs/devfs/*, include/linux/devfs_fs*.h will be removed,
+        along with the the assorted devfs function calls throughout the
+        kernel tree.
+Users:
diff --git a/Documentation/ABI/stable/syscalls b/Documentation/ABI/stable/syscalls
new file mode 100644
index 000000000000..c3ae3e7d6a0c
--- /dev/null
+++ b/Documentation/ABI/stable/syscalls
@@ -0,0 +1,10 @@
+What:           The kernel syscall interface
+Description:
+        This interface matches much of the POSIX interface and is based
+        on it and other Unix based interfaces.  It will only be added to
+        over time, and not have things removed from it.
+        Note that this interface is different for every architecture
+        that Linux supports.  Please see the architecture-specific
+        documentation for details on the syscall numbers that are to be
+        mapped to each syscall.
diff --git a/Documentation/ABI/stable/sysfs-module b/Documentation/ABI/stable/sysfs-module
new file mode 100644
index 000000000000..75be43118335
--- /dev/null
+++ b/Documentation/ABI/stable/sysfs-module
@@ -0,0 +1,30 @@
+What:           /sys/module
+Description:
+        The /sys/module tree consists of the following structure:
+        /sys/module/MODULENAME
+                The name of the module that is in the kernel.  This
+                module name will show up either if the module is built
+                directly into the kernel, or if it is loaded as a
+                dyanmic module.
+        /sys/module/MODULENAME/parameters
+                This directory contains individual files that are each
+                individual parameters of the module that are able to be
+                changed at runtime.  See the individual module
+                documentation as to the contents of these parameters and
+                what they accomplish.
+                Note: The individual parameter names and values are not
+                considered stable, only the fact that they will be
+                placed in this location within sysfs.  See the
+                individual driver documentation for details as to the
+                stability of the different parameters.
+        /sys/module/MODULENAME/refcnt
+                If the module is able to be unloaded from the kernel, this file
+                will contain the current reference count of the module.
+                Note: If the module is built into the kernel, or if the
+                CONFIG_MODULE_UNLOAD kernel configuration value is not enabled,
+                this file will not be present.
diff --git a/Documentation/ABI/testing/sysfs-class b/Documentation/ABI/testing/sysfs-class
new file mode 100644
index 000000000000..4b0cb891e46e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class
@@ -0,0 +1,16 @@
+What:           /sys/class/
+Date:           Febuary 2006
+Contact:        Greg Kroah-Hartman <gregkh@suse.de>
+Description:
+                The /sys/class directory will consist of a group of
+                subdirectories describing individual classes of devices
+                in the kernel.  The individual directories will consist
+                of either subdirectories, or symlinks to other
+                directories.
+                All programs that use this directory tree must be able
+                to handle both subdirectories or symlinks in order to
+                work properly.
+Users:
+        udev <linux-hotplug-devel@lists.sourceforge.net>
diff --git a/Documentation/ABI/testing/sysfs-devices b/Documentation/ABI/testing/sysfs-devices
new file mode 100644
index 000000000000..6a25671ee5f6
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices
@@ -0,0 +1,25 @@
+What:           /sys/devices
+Date:           February 2006
+Contact:        Greg Kroah-Hartman <gregkh@suse.de>
+Description:
+                The /sys/devices tree contains a snapshot of the
+                internal state of the kernel device tree.  Devices will
+                be added and removed dynamically as the machine runs,
+                and between different kernel versions, the layout of the
+                devices within this tree will change.
+                Please do not rely on the format of this tree because of
+                this.  If a program wishes to find different things in
+                the tree, please use the /sys/class structure and rely
+                on the symlinks there to point to the proper location
+                within the /sys/devices tree of the individual devices.
+                Or rely on the uevent messages to notify programs of
+                devices being added and removed from this tree to find
+                the location of those devices.
+                Note that sometimes not all devices along the directory
+                chain will have emitted uevent messages, so userspace
+                programs must be able to handle such occurrences.
+Users:
+        udev <linux-hotplug-devel@lists.sourceforge.net>

diff --git a/Documentation/ABI/README b/Documentation/ABI/README new file mode 100644 index 000000000000..9feaf16f1617 --- /dev/null +++ b/Documentation/ABI/README
@@ -0,0 +1,77 @@
	1	This directory attempts to document the ABI between the Linux kernel and
	2	userspace, and the relative stability of these interfaces. Due to the
	3	everchanging nature of Linux, and the differing maturity levels, these
	4	interfaces should be used by userspace programs in different ways.
	5
	6	We have four different levels of ABI stability, as shown by the four
	7	different subdirectories in this location. Interfaces may change levels
	8	of stability according to the rules described below.
	9
	10	The different levels of stability are:
	11
	12	stable/
	13	This directory documents the interfaces that the developer has
	14	defined to be stable. Userspace programs are free to use these
	15	interfaces with no restrictions, and backward compatibility for
	16	them will be guaranteed for at least 2 years. Most interfaces
	17	(like syscalls) are expected to never change and always be
	18	available.
	19
	20	testing/
	21	This directory documents interfaces that are felt to be stable,
	22	as the main development of this interface has been completed.
	23	The interface can be changed to add new features, but the
	24	current interface will not break by doing this, unless grave
	25	errors or security problems are found in them. Userspace
	26	programs can start to rely on these interfaces, but they must be
	27	aware of changes that can occur before these interfaces move to
	28	be marked stable. Programs that use these interfaces are
	29	strongly encouraged to add their name to the description of
	30	these interfaces, so that the kernel developers can easily
	31	notify them if any changes occur (see the description of the
	32	layout of the files below for details on how to do this.)
	33
	34	obsolete/
	35	This directory documents interfaces that are still remaining in
	36	the kernel, but are marked to be removed at some later point in
	37	time. The description of the interface will document the reason
	38	why it is obsolete and when it can be expected to be removed.
	39	The file Documentation/feature-removal-schedule.txt may describe
	40	some of these interfaces, giving a schedule for when they will
	41	be removed.
	42
	43	removed/
	44	This directory contains a list of the old interfaces that have
	45	been removed from the kernel.
	46
	47	Every file in these directories will contain the following information:
	48
	49	What: Short description of the interface
	50	Date: Date created
	51	KernelVersion: Kernel version this feature first showed up in.
	52	Contact: Primary contact for this interface (may be a mailing list)
	53	Description: Long description of the interface and how to use it.
	54	Users: All users of this interface who wish to be notified when
	55	it changes. This is very important for interfaces in
	56	the "testing" stage, so that kernel developers can work
	57	with userspace developers to ensure that things do not
	58	break in ways that are unacceptable. It is also
	59	important to get feedback for these interfaces to make
	60	sure they are working in a proper way and do not need to
	61	be changed further.
	62
	63
	64	How things move between levels:
	65
	66	Interfaces in stable may move to obsolete, as long as the proper
	67	notification is given.
	68
	69	Interfaces may be removed from obsolete and the kernel as long as the
	70	documented amount of time has gone by.
	71
	72	Interfaces in the testing state can move to the stable state when the
	73	developers feel they are finished. They cannot be removed from the
	74	kernel tree without going through the obsolete state first.
	75
	76	It's up to the developer to place their interfaces in the category they
	77	wish for it to start out in.


diff --git a/Documentation/ABI/obsolete/devfs b/Documentation/ABI/obsolete/devfs new file mode 100644 index 000000000000..b8b87399bc8f --- /dev/null +++ b/Documentation/ABI/obsolete/devfs
@@ -0,0 +1,13 @@
	1	What: devfs
	2	Date: July 2005
	3	Contact: Greg Kroah-Hartman <gregkh@suse.de>
	4	Description:
	5	devfs has been unmaintained for a number of years, has unfixable
	6	races, contains a naming policy within the kernel that is
	7	against the LSB, and can be replaced by using udev.
	8	The files fs/devfs/, include/linux/devfs_fs.h will be removed,
	9	along with the the assorted devfs function calls throughout the
	10	kernel tree.
	11
	12	Users:
	13


diff --git a/Documentation/ABI/stable/syscalls b/Documentation/ABI/stable/syscalls new file mode 100644 index 000000000000..c3ae3e7d6a0c --- /dev/null +++ b/Documentation/ABI/stable/syscalls
@@ -0,0 +1,10 @@
	1	What: The kernel syscall interface
	2	Description:
	3	This interface matches much of the POSIX interface and is based
	4	on it and other Unix based interfaces. It will only be added to
	5	over time, and not have things removed from it.
	6
	7	Note that this interface is different for every architecture
	8	that Linux supports. Please see the architecture-specific
	9	documentation for details on the syscall numbers that are to be
	10	mapped to each syscall.


diff --git a/Documentation/ABI/stable/sysfs-module b/Documentation/ABI/stable/sysfs-module new file mode 100644 index 000000000000..75be43118335 --- /dev/null +++ b/Documentation/ABI/stable/sysfs-module
@@ -0,0 +1,30 @@
	1	What: /sys/module
	2	Description:
	3	The /sys/module tree consists of the following structure:
	4
	5	/sys/module/MODULENAME
	6	The name of the module that is in the kernel. This
	7	module name will show up either if the module is built
	8	directly into the kernel, or if it is loaded as a
	9	dyanmic module.
	10
	11	/sys/module/MODULENAME/parameters
	12	This directory contains individual files that are each
	13	individual parameters of the module that are able to be
	14	changed at runtime. See the individual module
	15	documentation as to the contents of these parameters and
	16	what they accomplish.
	17
	18	Note: The individual parameter names and values are not
	19	considered stable, only the fact that they will be
	20	placed in this location within sysfs. See the
	21	individual driver documentation for details as to the
	22	stability of the different parameters.
	23
	24	/sys/module/MODULENAME/refcnt
	25	If the module is able to be unloaded from the kernel, this file
	26	will contain the current reference count of the module.
	27
	28	Note: If the module is built into the kernel, or if the
	29	CONFIG_MODULE_UNLOAD kernel configuration value is not enabled,
	30	this file will not be present.


diff --git a/Documentation/ABI/testing/sysfs-class b/Documentation/ABI/testing/sysfs-class new file mode 100644 index 000000000000..4b0cb891e46e --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class
@@ -0,0 +1,16 @@
	1	What: /sys/class/
	2	Date: Febuary 2006
	3	Contact: Greg Kroah-Hartman <gregkh@suse.de>
	4	Description:
	5	The /sys/class directory will consist of a group of
	6	subdirectories describing individual classes of devices
	7	in the kernel. The individual directories will consist
	8	of either subdirectories, or symlinks to other
	9	directories.
	10
	11	All programs that use this directory tree must be able
	12	to handle both subdirectories or symlinks in order to
	13	work properly.
	14
	15	Users:
	16	udev <linux-hotplug-devel@lists.sourceforge.net>


diff --git a/Documentation/ABI/testing/sysfs-devices b/Documentation/ABI/testing/sysfs-devices new file mode 100644 index 000000000000..6a25671ee5f6 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices
@@ -0,0 +1,25 @@
	1	What: /sys/devices
	2	Date: February 2006
	3	Contact: Greg Kroah-Hartman <gregkh@suse.de>
	4	Description:
	5	The /sys/devices tree contains a snapshot of the
	6	internal state of the kernel device tree. Devices will
	7	be added and removed dynamically as the machine runs,
	8	and between different kernel versions, the layout of the
	9	devices within this tree will change.
	10
	11	Please do not rely on the format of this tree because of
	12	this. If a program wishes to find different things in
	13	the tree, please use the /sys/class structure and rely
	14	on the symlinks there to point to the proper location
	15	within the /sys/devices tree of the individual devices.
	16	Or rely on the uevent messages to notify programs of
	17	devices being added and removed from this tree to find
	18	the location of those devices.
	19
	20	Note that sometimes not all devices along the directory
	21	chain will have emitted uevent messages, so userspace
	22	programs must be able to handle such occurrences.
	23
	24	Users:
	25	udev <linux-hotplug-devel@lists.sourceforge.net>