kobject: make uevent_seqnum atomic

We will soon no longer acquire uevent_sock_mutex
for most kobject_uevent_net_broadcast() calls,
and also while calling uevent_net_broadcast().

Make uevent_seqnum an atomic64_t to get its own protection.

This fixes a race while reading /sys/kernel/uevent_seqnum.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christian Brauner <brauner@kernel.org>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20240214084829.684541-2-edumazet@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: Reorder fields in 'struct kobject'

Group some variables based on their sizes to reduce hole and avoid padding.
On x86_64, this shrinks the size of 'struct kobject' from 256 to 244 bytes.

This structure is often included in some other structures. So these other
structures will also benefit from this 8 bytes saving.

This is especially nice for structure like 'cma_kobject' or 'class_dir'
that are now 256 bytes long. When they are kzalloc()'ed, 256 bytes are
allocated, instead of 512.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/6c7d1e3005dbec5483bdb9b7b60071175bf7bf70.1688811201.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject.h remove extern from function prototypes

The kernel coding style does not require 'extern' in function prototypes
in .h files, so remove them from include/linux/kobject.h as they are not
needed.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230324122711.2664537-6-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: kset_uevent_ops: make uevent() callback take a const *

The uevent() callback in struct kset_uevent_ops does not modify the
kobject passed into it, so make the pointer const to enforce this
restriction. When doing so, fix up all existing uevent() callbacks to
have the correct signature to preserve the build.

Cc: Christine Caulfield <ccaulfie@redhat.com>
Cc: David Teigland <teigland@redhat.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-17-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: kset_uevent_ops: make name() callback take a const *

The name() callback in struct kset_uevent_ops does not modify the
kobject passed into it, so make the pointer const to enforce this
restriction. When doing so, fix up the single existing name() callback
to have the correct signature to preserve the build.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20221121094649.1556002-4-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: kset_uevent_ops: make filter() callback take a const *

The filter() callback in struct kset_uevent_ops does not modify the
kobject passed into it, so make the pointer const to enforce this
restriction. When doing so, fix up all existing filter() callbacks to
have the correct signature to preserve the build.

Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Christian König <christian.koenig@amd.com> for the changes to
Link: https://lore.kernel.org/r/20221121094649.1556002-3-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: make kobject_namespace take a const *

kobject_namespace() should take a const *kobject as it does not modify
the kobject passed to it. Change that, and the functions
kobj_child_ns_ops() and kobj_ns_ops() needed to also be changed to const
*.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20221121094649.1556002-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: make kobject_get_ownership() take a constant kobject *

The call, kobject_get_ownership(), does not modify the kobject passed
into it, so make it const. This propagates down into the kobj_type
function callbacks so make the kobject passed into them also const,
ensuring that nothing in the kobject is being changed here.

This helps make it more obvious what calls and callbacks do, and do not,
modify structures passed to them.

Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Roopa Prabhu <roopa@nvidia.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: linux-nfs@vger.kernel.org
Cc: bridge@lists.linux-foundation.org
Cc: netdev@vger.kernel.org
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20221121094649.1556002-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: make get_ktype() take a const pointer

get_ktype() does not modify the structure passed to it, so mark the
parameter as being const to allow other const structures to be passed to
it in the future.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20221021072310.3931690-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: modify kobject_get_path() to take a const *

kobject_get_path() does not modify the kobject passed to it, so make the
pointer constant.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20221001165315.2690141-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: kobj_type: remove default_attrs

Now that all in-kernel users of default_attrs for the kobj_type are gone
and converted to properly use the default_groups pointer instead, it can
be safely removed.

There is one standard way to create sysfs files in a kobj_type, and not
two like before, causing confusion as to which should be used.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20220106133151.607703-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

headers/uninline: Uninline single-use function: kobject_has_children()

This was the only usage of <linux/kref_api.h> in <linux/kobject_api.h>,
so we'll able to decouple the two after this change.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: remove kset from struct kset_uevent_ops callbacks

There is no need to pass the pointer to the kset in the struct
kset_uevent_ops callbacks as no one uses it, so just remove that pointer
entirely.

Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Wedson Almeida Filho <wedsonaf@google.com>
Link: https://lore.kernel.org/r/20211227163924.3970661-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

driver core: make kobj_type constant.

This way instances of kobj_type (which contain function pointers) can be
stored in .rodata, which means that they cannot be [easily/accidentally]
modified at runtime.

Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Link: https://lore.kernel.org/r/20211224231345.777370-1-wedsonaf@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: Replace kernel.h with the necessary inclusions

When kernel.h is used in the headers it adds a lot into dependency hell,
especially when there are circular dependencies are involved.

Replace kernel.h inclusion with the list of what is really being used.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211110103128.59888-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: unexport kobject_create() in kobject.h

The function kobject_create() is only used by one caller,
kobject_create_and_add(), no other driver uses it, nor is exported to
other modules.

However it's still exported in kobject.h, and can sometimes confuse
users of kobject.h.

Since all users should call kobject_create_and_add(), or if extra
attributes are needed, should alloc the memory manually then call
kobject_init_and_add().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Link: https://lore.kernel.org/r/20210831093044.110729-1-wqu@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: remove unused KOBJ_MAX action

The loop in libb/kobj_uevent.c that checked for KOBBJ_MAX is no longer
present, we do a much more sane ARRAY_SIZE() check instead. See
5c5daf657cb5 ("Driver core: exclude kobject_uevent.c for
!CONFIG_HOTPLUG").

Signed-off-by: Garrit Franke <garritfranke@gmail.com>
Link: https://lore.kernel.org/r/20200716203100.7959-1-garritfranke@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: increase allowed number of uevent variables

SBS battery driver exposes 32 power supply properties now,
which will result in uevent failure on (un)plugging the
battery. Other drivers (e.g. bq27xxx) are also coming close
to this limit, so increase it.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

docs: filesystems: fix renamed references

Some filesystem references got broken by a previous patch
series I submitted. Address those.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: David Sterba <dsterba@suse.com> # fs/affs/Kconfig
Link: https://lore.kernel.org/r/57318c53008dbda7f6f4a5a9e5787f4d37e8565a.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

kobject: Add support for default attribute groups to kobj_type

kobj_type currently uses a list of individual attributes to store
default attributes. Attribute groups are more flexible than a list of
attributes because groups provide support for attribute visibility. So,
add support for default attribute groups to kobj_type.

In future patches, the existing uses of kobj_type’s attribute list will
be converted to attribute groups. When that is complete, kobj_type’s
attribute list, “default_attrs”, will be removed.

Signed-off-by: Kimberly Brown <kimbrownkd@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sysfs, kobject: allow creating kobject belonging to arbitrary users

Normally kobjects and their sysfs representation belong to global root,
however it is not necessarily the case for objects in separate namespaces.
For example, objects in separate network namespace logically belong to the
container's root and not global root.

This change lays groundwork for allowing network namespace objects
ownership to be transferred to container's root user by defining
get_ownership() callback in ktype structure and using it in sysfs code to
retrieve desired uid/gid when creating sysfs objects for given kobject.

Co-Developed-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers: core: Remove glue dirs from sysfs earlier

For devices with a class, we create a "glue" directory between
the parent device and the new device with the class name.

This directory is never "explicitely" removed when empty however,
this is left to the implicit sysfs removal done by kobject_release()
when the object loses its last reference via kobject_put().

This is problematic because as long as it's not been removed from
sysfs, it is still present in the class kset and in sysfs directory
structure.

The presence in the class kset exposes a use after free bug fixed
by the previous patch, but the presence in sysfs means that until
the kobject is released, which can take a while (especially with
kobject debugging), any attempt at re-creating such as binding a
new device for that class/parent pair, will result in a sysfs
duplicate file name error.

This fixes it by instead doing an explicit kobject_del() when
the glue dir is empty, by keeping track of the number of
child devices of the gluedir.

This is made easy by the fact that all glue dir operations are
done with a global mutex, and there's already a function
(cleanup_glue_dir) called in all the right places taking that
mutex that can be enhanced for this. It appears that this was
in fact the intent of the function, but the implementation was
wrong.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: Remove redundant license text

Now that the SPDX tag is in all kobject files, that identifies the
license in a specific and legally-defined manner. So the extra GPL text
wording can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: add SPDX identifiers to all kobject files

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the kobject files files with the correct SPDX license identifier
based on the license text in the file itself. The SPDX identifier is a
legally binding shorthand, which can be used instead of the full boiler
plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

driver core: emit uevents when device is bound to a driver

There are certain touch controllers that may come up in either normal
(application) or boot mode, depending on whether firmware/configuration is
corrupted when they are powered on. In boot mode the kernel does not create
input device instance (because it does not necessarily know the
characteristics of the input device in question).

Another number of controllers does not store firmware in a non-volatile
memory, and they similarly need to have firmware loaded before input device
instance is created. There are also other types of devices with similar
behavior.

There is a desire to be able to trigger firmware loading via udev, but it
has to happen only when driver is bound to a physical device (i2c or spi).
These udev actions can not use ADD events, as those happen too early, so we
are introducing BIND and UNBIND events that are emitted at the right
moment.

Also, many drivers create additional driver-specific device attributes
when binding to the device, to provide userspace with additional controls.
The new events allow userspace to adjust these driver-specific attributes
without worrying that they are not there yet.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

randstruct: Mark various structs for randomization

This marks many critical kernel structures for randomization. These are
structures that have been targeted in the past in security exploits, or
contain functions pointers, pointers to function pointer tables, lists,
workqueues, ref-counters, credentials, permissions, or are otherwise
sensitive. This initial list was extracted from Brad Spengler/PaX Team's
code in the last public patch of grsecurity/PaX based on my understanding
of the code. Changes or omissions from the original code are mine and
don't reflect the original grsecurity/PaX code.

Left out of this list is task_struct, which requires special handling
and will be covered in a subsequent patch.

Signed-off-by: Kees Cook <keescook@chromium.org>

kobject: support passing in variables for synthetic uevents

This patch makes it possible to pass additional arguments in addition
to uevent action name when writing /sys/.../uevent attribute. These
additional arguments are then inserted into generated synthetic uevent
as additional environment variables.

Before, we were not able to pass any additional uevent environment
variables for synthetic uevents. This made it hard to identify such uevents
properly in userspace to make proper distinction between genuine uevents
originating from kernel and synthetic uevents triggered from userspace.
Also, it was not possible to pass any additional information which would
make it possible to optimize and change the way the synthetic uevents are
processed back in userspace based on the originating environment of the
triggering action in userspace. With the extra additional variables, we are
able to pass through this extra information needed and also it makes it
possible to synchronize with such synthetic uevents as they can be clearly
identified back in userspace.

The format for writing the uevent attribute is following:

ACTION [UUID [KEY=VALUE ...]

There's no change in how "ACTION" is recognized - it stays the same
("add", "change", "remove"). The "ACTION" is the only argument required
to generate synthetic uevent, the rest of arguments, that this patch
adds support for, are optional.

The "UUID" is considered as transaction identifier so it's possible to
use the same UUID value for one or more synthetic uevents in which case
we logically group these uevents together for any userspace listeners.
The "UUID" is expected to be in "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
format where "x" is a hex digit. The value appears in uevent as
"SYNTH_UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" environment variable.

The "KEY=VALUE" pairs can contain alphanumeric characters only. It's
possible to define zero or more more pairs - each pair is then delimited
by a space character " ". Each pair appears in synthetic uevents as
"SYNTH_ARG_KEY=VALUE" environment variable. That means the KEY name gains
"SYNTH_ARG_" prefix to avoid possible collisions with existing variables.
To pass the "KEY=VALUE" pairs, it's also required to pass in the "UUID"
part for the synthetic uevent first.

If "UUID" is not passed in, the generated synthetic uevent gains
"SYNTH_UUID=0" environment variable automatically so it's possible to
identify this situation in userspace when reading generated uevent and so
we can still make a difference between genuine and synthetic uevents.

Signed-off-by: Peter Rajnoha <prajnoha@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: Export kobject_get_unless_zero()

Make the function available for outside use and fortify it against NULL
kobject.

CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>

kobject: explain what kobject's sd field is

(More) unclear, especially name-wise, after sysfs_dirent became
kernfs_node.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include, lib: add __printf attributes to several function prototypes

Using __printf attributes helps to detect several format string issues
at compile time (even though -Wformat-security is currently disabled in
Makefile). For example it can detect when formatting a pointer as a
number, like the issue fixed in commit a3fa71c40f18 ("wl18xx: show
rx_frames_per_rates as an array as it really is"), or when the arguments
do not match the format string, c.f. for example commit 5ce1aca81435
("reiserfs: fix __RASSERT format string").

To prevent similar bugs in the future, add a __printf attribute to every
function prototype which needs one in include/linux/ and lib/. These
functions were mostly found by using gcc's -Wsuggest-attribute=format
flag.

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kobject: Make support for uevent_helper optional.

Support for uevent_helper, aka hotplug, is not required on many systems
these days but it can still be enabled via sysfs or sysctl.

Reported-by: Darren Shepherd <darren.s.shepherd@gmail.com>
Signed-off-by: Michael Marineau <mike@marineau.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: don't block for each kobject_uevent

Currently kobject_uevent has somewhat unpredictable semantics. The
point is, since it may call a usermode helper and wait for it to execute
(UMH_WAIT_EXEC), it is impossible to say for sure what lock dependencies
it will introduce for the caller - strictly speaking it depends on what
fs the binary is located on and the set of locks fork may take. There
are quite a few kobject_uevent's users that do not take this into
account and call it with various mutexes taken, e.g. rtnl_mutex,
net_mutex, which might potentially lead to a deadlock.

Since there is actually no reason to wait for the usermode helper to
execute there, let's make kobject_uevent start the helper asynchronously
with the aid of the UMH_NO_WAIT flag.

Personally, I'm interested in this, because I really want kobject_uevent
to be called under the slab_mutex in the slub implementation as it used
to be some time ago, because it greatly simplifies synchronization and
automatically fixes a kmemcg-related race. However, there was a
deadlock detected on an attempt to call kobject_uevent under the
slab_mutex (see https://lkml.org/lkml/2012/1/14/45), which was reported
to be fixed by releasing the slab_mutex for kobject_uevent.

Unfortunately, there was no information about who exactly blocked on the
slab_mutex causing the usermode helper to stall, neither have I managed
to find this out or reproduce the issue.

BTW, this is not the first attempt to make kobject_uevent use
UMH_NO_WAIT. Previous one was made by commit f520360d93cd ("kobject:
don't block for each kobject_uevent"), but it was wrong (it passed
arguments allocated on stack to async thread) so it was reverted in
05f54c13cd0c ("Revert "kobject: don't block for each kobject_uevent".").
It targeted on speeding up the boot process though.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Greg KH <greg@kroah.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernfs: s/sysfs_dirent/kernfs_node/ and rename its friends accordingly

kernfs has just been separated out from sysfs and we're already in
full conflict mode. Nothing can make the situation any worse. Let's
take the chance to name things properly.

This patch performs the following renames.

* s/sysfs_elem_dir/kernfs_elem_dir/
* s/sysfs_elem_symlink/kernfs_elem_symlink/
* s/sysfs_elem_attr/kernfs_elem_file/
* s/sysfs_dirent/kernfs_node/
* s/sd/kn/ in kernfs proper
* s/parent_sd/parent/
* s/target_sd/target/
* s/dir_sd/parent/
* s/to_sysfs_dirent()/rb_to_kn()/
* misc renames of local vars when they conflict with the above

Because md, mic and gpio dig into sysfs details, this patch ends up
modifying them. All are sysfs_dirent renames and trivial. While we
can avoid these by introducing a dummy wrapping struct sysfs_dirent
around kernfs_node, given the limited usage outside kernfs and sysfs
proper, I don't think such workaround is called for.

This patch is strictly rename only and doesn't introduce any
functional difference.

- mic / gpio renames were missing. Spotted by kbuild test robot.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Ashutosh Dixit <ashutosh.dixit@intel.com>
Cc: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sysfs: remove ktype->namespace() invocations in directory code

For some unrecognizable reason, namespace information is communicated
to sysfs through ktype->namespace() callback when there's *nothing*
which needs the use of a callback. The whole sequence of operations
is completely synchronous and sysfs operations simply end up calling
back into the layer which just invoked it in order to find out the
namespace information, which is completely backwards, obfuscates
what's going on and unnecessarily tangles two separate layers.

This patch doesn't remove ktype->namespace() but shifts its handling
to kobject layer. We probably want to get rid of the callback in the
long term.

This patch adds an explicit param to sysfs_{create|rename|move}_dir()
and renames them to sysfs_{create|rename|move}_dir_ns(), respectively.
ktype->namespace() invocations are moved to the calling sites of the
above functions. A new helper kboject_namespace() is introduced which
directly tests kobj_ns_type_operations->type which should give the
same result as testing sysfs_fs_type(parent_sd) and returns @kobj's
namespace tag as necessary. kobject_namespace() is extern as it will
be used from another file in the following patches.

This patch should be an equivalent conversion without any functional
difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: delayed kobject release: help find buggy drivers

Implement debugging for kobject release functions. kobjects are
reference counted, so the drop of the last reference to them is not
predictable. However, the common case is for the last reference to be
the kobject's removal from a subsystem, which results in the release
function being immediately called.

This can hide subtle bugs, which can occur when another thread holds a
reference to the kobject at the same time that a kobject is removed.
This results in the release method being delayed.

In order to make these kinds of problems more visible, the following
patch implements a delayed release; this has the effect that the
release function will be out of order with respect to the removal of
the kobject in the same manner that it would be if a reference was
being held.

This provides us with an easy way to allow driver writers to debug
their drivers and fix otherwise hidden problems.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: remove CONFIG_HOTPLUG ifdefs

Remove conditional code based on CONFIG_HOTPLUG being false. It's
always on now in preparation of it going away as an option.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: fix oops with "input0: bad kobj_uevent_env content in show_uevent()"

Fengguang Wu <fengguang.wu@intel.com> writes:

> After the __devinit* removal series, I can still get kernel panic in
> show_uevent(). So there are more sources of bug..
>
> Debug patch:
>
> @@ -343,8 +343,11 @@ static ssize_t show_uevent(struct device
> goto out;
>
> /* copy keys to file */
> - for (i = 0; i < env->envp_idx; i++)
> + dev_err(dev, "uevent %d env[%d]: %s/.../%s\n", env->buflen, env->envp_idx, top_kobj->name, dev->kobj.name);
> + for (i = 0; i < env->envp_idx; i++) {
> + printk(KERN_ERR "uevent %d env[%d]: %s\n", (int)count, i, env->envp[i]);
> count += sprintf(&buf[count], "%s\n", env->envp[i]);
> + }
>
> Oops message, the env[] is again not properly initilized:
>
> [ 44.068623] input input0: uevent 61 env[805306368]: input0/.../input0
> [ 44.069552] uevent 0 env[0]: (null)

This is a completely different CONFIG_HOTPLUG problem, only
demonstrating another reason why CONFIG_HOTPLUG should go away. I had a
hard time trying to disable it anyway ;-)

The problem this time is lots of code assuming that a call to
add_uevent_var() will guarantee that env->buflen > 0. This is not true
if CONFIG_HOTPLUG is unset. So things like this end up overwriting
env->envp_idx because the array index is -1:

if (add_uevent_var(env, "MODALIAS="))
return -ENOMEM;
len = input_print_modalias(&env->buf[env->buflen - 1],
sizeof(env->buf) - env->buflen,
dev, 0);

Don't know what the best action is, given that there seem to be a *lot*
of this around the kernel. This patch "fixes" the problem for me, but I
don't know if it can be considered an appropriate fix.

[ It is the correct fix for now, for 3.7 forcing CONFIG_HOTPLUG to
always be on is the longterm fix, but it's too late for 3.6 and older
kernels to resolve this that way - gregkh ]

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Tested-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kobject: remove kset_find_obj_hinted()

Now that there are no in-kernel users of this function, remove it as it
is no longer needed.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

treewide: use __printf not __attribute__((format(printf,...)))

Standardize the style for compiler based printf format verification.
Standardized the location of __printf too.

Done via script and a little typing.

$ grep -rPl --include=*.[ch] -w "__attribute__" * | \
grep -vP "^(tools|scripts|include/linux/compiler-gcc.h)" | \
xargs perl -n -i -e 'local $/; while (<>) { s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf\s*,\s*(.+)\s*,\s*(.+)\s*\)\s*\)\s*\)/__printf($1, $2)/g ; print; }'

[akpm@linux-foundation.org: revert arch bits]
Signed-off-by: Joe Perches <joe@perches.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

atomic: use <linux/atomic.h>

This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kobject.h: fix build when CONFIG_HOTPLUG is disabled

When CONFIG_HOTPLUG is not enabled, the inline function add_uevent_var()
needs to have its __attribute__ before the function name/parameters,
otherwise there are syntax errors.

linux-next-20110207/include/linux/kobject.h:232: error: expected ',' or ';' before '{' token

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: Add missing format attribute specifications

Several functions in <linux/kobject.h> accept printf-style arguments.
Some of these functions have been annotated with a format attribute
declaration while others have not been annotated. Add a format attribute
specification where it is missing.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: Introduce kset_find_obj_hinted.

One call chain getting to kset_find_obj is:
link_mem_sections()
find_mem_section()
kset_find_obj()

This is done during boot. The memory sections were added in a linearly
increasing order and link_mem_sections tends to utilize them in that
same linear order.

Introduce a kset_find_obj_hinted which is passed the result of the
previous kset_find_obj which it uses for a quick "is the next object
our desired object" check before falling back to the old behavior.

Signed-off-by: Robin Holt <holt@sgi.com>
To: Robert P. J. Day <rpjday@crashcourse.ca>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: Break the kobject namespace defs into their own header

Break the kobject namespace defs into their own header to avoid a header file
inclusion ordering problem between linux/sysfs.h and linux/kobject.h.

This fixes the build breakage on older versions of gcc.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

netns: Teach network device kobjects which namespace they are in.

The problem. Network devices show up in sysfs and with the network
namespace active multiple devices with the same name can show up in
the same directory, ouch!

To avoid that problem and allow existing applications in network namespaces
to see the same interface that is currently presented in sysfs, this
patch enables the tagging directory support in sysfs.

By using the network namespace pointers as tags to separate out the
the sysfs directory entries we ensure that we don't have conflicts
in the directories and applications only see a limited set of
the network devices.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobj: Add basic infrastructure for dealing with namespaces.

Move complete knowledge of namespaces into the kobject layer
so we can use that information when reporting kobjects to
userspace.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

sysfs: Comment sysfs directory tagging logic

Add some in-line comments to explain the new infrastructure, which
was introduced to support sysfs directory tagging with namespaces.
I think an overall description someplace might be good too, but it
didn't really seem to fit into Documentation/filesystems/sysfs.txt,
which appears more geared toward users, rather than maintainers, of
sysfs.

(Tejun, please let me know if I can make anything clearer or failed
altogether to comment something that should be commented.)

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver core: Constify struct sysfs_ops in struct kobj_type

Constify struct sysfs_ops.

This is part of the ops structure constification
effort started by Arjan van de Ven et al.

Benefits of this constification:

* prevents modification of data that is shared
(referenced) by many other structure instances
at runtime

* detects/prevents accidental (but not intentional)
modification attempts on archs that enforce
read-only kernel data at runtime

* potentially better optimized code as the compiler
can assume that the const data cannot be changed

* the compiler/linker move const data into .rodata
and therefore exclude them from false sharing

Signed-off-by: Emese Revfy <re.emese@gmail.com>
Acked-by: David Teigland <teigland@redhat.com>
Acked-by: Matt Domsch <Matt_Domsch@dell.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Acked-by: Hans J. Koch <hjk@linutronix.de>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: Constify struct kset_uevent_ops

Constify struct kset_uevent_ops.

This is part of the ops structure constification
effort started by Arjan van de Ven et al.

Benefits of this constification:

* prevents modification of data that is shared
(referenced) by many other structure instances
at runtime

* detects/prevents accidental (but not intentional)
modification attempts on archs that enforce
read-only kernel data at runtime

* potentially better optimized code as the compiler
can assume that the const data cannot be changed

* the compiler/linker move const data into .rodata
and therefore exclude them from false sharing

Signed-off-by: Emese Revfy <re.emese@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver core: implement uevent suppress in kobject

This patch implements uevent suppress in kobject and removes it
from struct device, based on the following ideas:

1,Uevent sending should be one attribute of kobject, so suppressing it
in kobject layer is more natural than in device layer. By this way,
we can do it for other objects embedded with kobject.

2,It may save several bytes for each instance of struct device.(On my
omap3(32bit ARM) based box, can save 8bytes per device object)

This patch also introduces dev_set|get_uevent_suppress() helpers to
set and query uevent_suppress attribute in case to help kobject
as private part of struct device in future.

[This version is against the latest driver-core patch set of Greg,please
ignore the last version.]

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

driver core: get rid of struct device's bus_id string array

Now that all users of bus_id is gone, we can remove it from struct
device.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

mm: create /sys/kernel/mm

Add a kobject to create /sys/kernel/mm when sysfs is mounted. The kobject
will exist regardless. This will allow for the hugepage related sysfs
directories to exist under the mm "subsystem" directory. Add an ABI file
appropriately.

[kosaki.motohiro@jp.fujitsu.com: fix build]
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kobject: reorder kobject to save space on 64 bit builds

reorder kobject to save space on 64 bit builds.
shrinks from 72 to 64 bytes & moves allocated kobject to a smaller
slab.

Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

driver core: remove KOBJ_NAME_LEN define

Kobjects do not have a limit in name size since a while, so stop
pretending that they do.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Remove "#ifdef __KERNEL__" checks from unexported headers

Remove the "#ifdef __KERNEL__" tests from unexported header files in
linux/include whose entire contents are wrapped in that preprocessor
test.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Kobject: fix coding style issues in kobject.h

Finally clean up the odd spaces and other mess in kobject.h

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver core: change sysdev classes to use dynamic kobject names

All kobjects require a dynamically allocated name now. We no longer
need to keep track if the name is statically assigned, we can just
unconditionally free() all kobject names on cleanup.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Kobject: remove kobject_unregister() as no one uses it anymore

There are no in-kernel users of kobject_unregister() so it should be
removed.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Kobject: auto-cleanup on final unref

We save the current state in the object itself, so we can do proper
cleanup when the last reference is dropped.

If the initial reference is dropped, the object will be removed from
sysfs if needed, if an "add" event was sent, "remove" will be send, and
the allocated resources are released.

This allows us to clean up some driver core usage as well as allowing us
to do other such changes to the rest of the kernel.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Kset: remove kset_add function

No one is calling this anymore, so just remove it and hard-code the one
internal-use of it.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Kobject: remove kobject_register()

The function is no longer used by anyone in the kernel, and it prevents
the proper sending of the kobject uevent after the needed files are set
up by the caller. kobject_init_and_add() can be used in its place.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Kobject: rename kobject_init_ng() to kobject_init()

Now that the old kobject_init() function is gone, rename
kobject_init_ng() to kobject_init() to clean up the namespace.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Kobject: remove kobject_init() as no one uses it anymore

The old kobject_init() function is on longer in use, so let us remove it
from the public scope (kset mess in the kobject.c file still uses it,
but that can be cleaned up later very simply.)

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Kobject: rename kobject_add_ng() to kobject_add()

Now that the old kobject_add() function is gone, rename kobject_add_ng()
to kobject_add() to clean up the namespace.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Kobject: remove kobject_add() as no one uses it anymore

The old kobject_add() function is on longer in use, so let us remove it
from the public scope (kset mess in the kobject.c file still uses it,
but that can be cleaned up later very simply.)

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

driver core: make /sys/power a kobject

/sys/power should not be a kset, that's overkill. This patch renames it
to power_kset and fixes up all usages of it in the tree.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: remove subsystem_(un)register functions

These functions are no longer used and are the last remants of the old
subsystem crap. So delete them for good.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: convert kernel_kset to be a kobject

kernel_kset does not need to be a kset, but a much simpler kobject now
that we have kobj_attributes.

We also rename kernel_kset to kernel_kobj to catch all users of this
symbol with a build error instead of an easy-to-ignore build warning.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kset: remove decl_subsys macro

This macro is no longer used. ksets should be created dynamically with
a call to kset_create_and_add() not declared statically.

Yes, there are 5 remaining static struct kset usages in the kernel tree,
but they will be fixed up soon.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

firmware: change firmware_kset to firmware_kobj

There is no firmware "subsystem" it's just a directory in /sys that
other portions of the kernel want to hook into. So make it a kobject
not a kset to help alivate anyone who tries to do some odd kset-like
things with this.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver Core: kill subsys_attribute and default sysfs ops

Remove the no longer needed subsys_attributes, they are all converted to
the more sensical kobj_attributes.

There is no longer a magic fallback in sysfs attribute operations, all
kobjects which create simple attributes need explicitely a ktype
assigned, which tells the core what was intended here.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

firmware: export firmware_kset so that people can use that instead of the braindead firmware_register interface

Needed for future firmware subsystem cleanups.

In the end, the firmware_register/unregister functions will be deleted
entirely, but we need this symbol so that subsystems can migrate over.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Matt Domsch <Matt_Domsch@dell.com>
Cc: Matt Tolentino <matthew.e.tolentino@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver Core: add kobj_attribute handling

Add kobj_sysfs_ops to replace subsys_sysfs_ops. There is no
need for special kset operations, we want to be able to use
simple attribute operations at any kobject, not only ksets.

The whole concept of any default sysfs attribute operations
will go away with the upcoming removal of subsys_sysfs_ops.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kset: convert /sys/power to use kset_create

Dynamically create the kset instead of declaring it statically. We also
rename power_subsys to power_kset to catch all users of the variable and
we properly export it so that people don't have to guess that it really
is present in the system.

The pseries code is wierd, why is it createing /sys/power if CONFIG_PM
is disabled? Oh well, stupid big boxes ignoring config options...

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: convert /sys/hypervisor to use kobject_create

We don't need a kset here, a simple kobject will do just fine, so
dynamically create the kobject and use it.

We also rename hypervisor_subsys to hypervisor_kset to catch all users
of the variable.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kset: convert kernel_subsys to use kset_create

Dynamically create the kset instead of declaring it statically. We also
rename kernel_subsys to kernel_kset to catch all users of this symbol
with a build error instead of an easy-to-ignore build warning.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kset: remove decl_subsys_name

The last user of this macro (pci hotplug core) is now switched over to
using a dynamic kset, so this macro is no longer needed at all.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: get rid of kobject_kset_add_dir

kobject_kset_add_dir is only called in one place so remove it and use
kobject_create() instead.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: get rid of kobject_add_dir

kobject_create_and_add is the same as kobject_add_dir, so drop
kobject_add_dir.


Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: add kobject_create_and_add function

This lets users create dynamic kobjects much easier.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kset: add kset_create_and_add function

Now ksets can be dynamically created on the fly, no static definitions
are required. Thanks to Miklos for hints on how to make this work
better for the callers.

And thanks to Kay for finding some stupid bugs in my original version
and pointing out that we need to handle the fact that kobject's can have
a kset as a parent and to handle that properly in kobject_add().

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: remove kobj_set_kset_s as no one is using it anymore

What a confusing name for a macro...

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: remove struct kobj_type from struct kset

We don't need a "default" ktype for a kset. We should set this
explicitly every time for each kset. This change is needed so that we
can make ksets dynamic, and cleans up one of the odd, undocumented
assumption that the kset/kobject/ktype model has.

This patch is based on a lot of help from Kay Sievers.

Nasty bug in the block code was found by Dave Young
<hidave.darkstar@gmail.com>

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: add kobject_init_and_add function

Also add a kobject_init_and_add function which bundles up what a lot of
the current callers want to do all at once, and it properly handles the
memory usages, unlike kobject_register();

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: add kobject_add_ng function

This is what the kobject_add function is going to become.

Add this to the kernel and then we can convert the tree over to use it.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: add kobject_init_ng function

This is what the kobject_init function is going to become.

Add this to the kernel and then we can convert the tree over to use it.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: make kobject_cleanup be static

No one except the kobject core calls it so make the function static.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: update the copyrights

I've been hacking on these files for a while now, might as well make it
official...

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kset: add some kerneldoc to help describe what these strange things are

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

driver core: remove subsystem_init()

There is only one user of it, and it is only a wrapper for kset_init().

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

sysfs: move sysfs file poll implementation to sysfs_open_dirent

Sysfs file poll implementation is scattered over sysfs and kobject.
Event numbering is done in sysfs_dirent but wait itself is done on
kobject. This not only unecessarily bloats both kobject and
sysfs_dirent but is also buggy - if a sysfs_dirent is removed while
there still are pollers, the associaton betwen the kobject and
sysfs_dirent breaks and kobject may be freed with the pollers still
sleeping on it.

This patch moves whole poll implementation into sysfs_open_dirent.
Each time a sysfs_open_dirent is created, event number restarts from 1
and pollers sleep on sysfs_open_dirent. As event sequence number is
meaningless without any open file and pollers should have open file
and thus sysfs_open_dirent, this ephemeral event counting works and is
a saner implementation.

This patch fixes the dnagling sleepers bug and reduces the sizes of
kobject and sysfs_dirent by one pointer.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver core: exclude kobject_uevent.c for !CONFIG_HOTPLUG

Move uevent specific logic from the core into kobject_uevent.c, which
does no longer require to link the unused string array if hotplug
is not compiled in.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

sysfs: Remove first pass at shadow directory support

While shadow directories appear to be a good idea, the current scheme
of controlling their creation and destruction outside of sysfs appears
to be a locking and maintenance nightmare in the face of sysfs
directories dynamically coming and going. Which can now occur for
directories containing network devices when CONFIG_SYSFS_DEPRECATED is
not set.

This patch removes everything from the initial shadow directory support
that allowed the shadow directory creation to be controlled at a higher
level. So except for a few bits of sysfs_rename_dir everything from
commit b592fcfe7f06c15ec11774b5be7ce0de3aa86e73 is now gone.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: remove the static array for the name

Due to historical reasons, struct kobject contained a static array for
the name, and a dynamic pointer in case the name got bigger than the
array. That's just dumb, as people didn't always know which variable to
reference, even with the accessor for the kobject name.

This patch removes the static array, potentially saving a lot of memory
as the majority of kobjects do not have a very long name.

Thanks to Kay for the idea to do this.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver core: remove subsys_get()

There are no more subsystems, it's a kset now so remove the function and
the only two users, which are in the driver core.


Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver core: remove subsys_put()

There are no more subsystems, it's a kset now so remove the function and
the only two users, which are in the driver core.


Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver core: remove kset_set_kset_s

This macro is only used by the driver core and is held over from when we
had subsystems. It is not needed anymore.


Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver core: remove subsys_set_kset

This macro is only used by the driver core and is held over from when we
had subsystems. It is not needed anymore.


Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver core: change add_uevent_var to use a struct

This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.

Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kset: kernel-doc cleanups

Removed kernel-doc marker (/**) from struct kset -- each struct member
still needs annotation.

Corrected one parameter name so that kernel-doc matches the macro.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: put kobject_actions in kobject.h

This prevents the extern declaration in the driver core.

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Driver core: accept all valid action-strings in uevent-trigger

This allows the uevent file to handle any type of uevent action to be
triggered by userspace instead of just the "add" uevent.


Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

sysfs: make kobj point to sysfs_dirent instead of dentry

As kobj sysfs dentries and inodes are gonna be made reclaimable,
dentry can't be used as naming token for sysfs file/directory, replace
kobj->dentry with kobj->sd. The only external interface change is
shadow directory handling. All other changes are contained in kobj
and sysfs.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

remove "struct subsystem" as it is no longer needed

We need to work on cleaning up the relationship between kobjects, ksets and
ktypes. The removal of 'struct subsystem' is the first step of this,
especially as it is not really needed at all.

Thanks to Kay for fixing the bugs in this patch.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

the overdue removal of the mount/umount uevents

This patch contains the overdue removal of the mount/umount uevents.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject core: remove rwsem from struct subsystem

It isn't used at all by the driver core anymore, and the few usages of
it within the kernel have now all been fixed as most of them were using
it incorrectly. So remove it.

Now the whole struct subsys can be removed from the system, but that's
for a later patch...

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

driver core: fix namespace issue with devices assigned to classes

- uses a kset in "struct class" to keep track of all directories
belonging to this class
- merges with the /sys/devices/virtual logic.
- removes the namespace-dir if the last member of that class
leaves the directory.

There may be locking or refcounting fixes left, I stopped when it seemed
to work with network and sound modules. :)

From: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

sysfs: Shadow directory support

The problem. When implementing a network namespace I need to be able
to have multiple network devices with the same name. Currently this
is a problem for /sys/class/net/*.

What I want is a separate /sys/class/net directory in sysfs for each
network namespace, and I want to name each of them /sys/class/net.

I looked and the VFS actually allows that. All that is needed is
for /sys/class/net to implement a follow link method to redirect
lookups to the real directory you want.

Implementing a follow link method that is sensitive to the current
network namespace turns out to be 3 lines of code so it looks like a
clean approach. Modifying sysfs so it doesn't get in my was is a bit
trickier.

I am calling the concept of multiple directories all at the same path
in the filesystem shadow directories. With the directory entry really
at that location the shadow master.

The following patch modifies sysfs so it can handle a directory
structure slightly different from the kobject tree so I can implement
the shadow directories for handling /sys/class/net/.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kobject: kobject_uevent() returns manageable value

Since kobject_uevent() function does not return an integer value to
indicate if its operation was completed with success or not, it is worth
changing it in order to report a proper status (success or error) instead
of returning void.

[randy.dunlap@oracle.com: Fix inline kobject functions]
Cc: Mauricio Lin <mauriciolin@gmail.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@gmail.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

driver core: Introduce device_move(): move a device to a new parent.

Provide a function device_move() to move a device to a new parent device. Add
auxilliary functions kobject_move() and sysfs_move_dir().
kobject_move() generates a new uevent of type KOBJ_MOVE, containing the
previous path (DEVPATH_OLD) in addition to the usual values. For this, a new
interface kobject_uevent_env() is created that allows to add further
environmental data to the uevent at the kobject layer.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

add __must_check to device management code

We're getting a lot of crashes in the sysfs/kobject/device/bus/class code and
they're very hard to diagnose.

I'm suspecting that in some cases this is because drivers aren't checking
return values and aren't handling errors correctly. So the code blithely
blunders on and crashes later in very obscure ways.

There's just no reason to ignore errors which can and do occur. So the patch
sprinkles __must_check all over these APIs.

Causes 1,513 new warnings. Heh.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

PCI: docking station: remove dock uevents

Remove uevent dock notifications. There are no consumers
of these events at present, and uevents are likely not the
correct way to send this type of event anyway.

Until I get some kind of idea if anyone in userspace cares
about dock events, I will just not send any.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

KEVENT: add new uevent for dock

so that userspace can be notified of dock and undock events.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>

[PATCH] Driver Core: Add /sys/hypervisor when needed

To have a home for all hypervisors, this patch creates /sys/hypervisor.
A new config option SYS_HYPERVISOR is introduced, which should to be set
by architecture dependent hypervisors (e.g. s390 or Xen).

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] Kobject: possible cleanups

This patch contains the following possible cleanups:
- #if 0 the following unused global function:
- subsys_remove_file()
- remove the following unused EXPORT_SYMBOL's:
- kset_find_obj
- subsystem_init
- remove the following unused EXPORT_SYMBOL_GPL:
- kobject_add_dir

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] Kobject: fix build error

This fixes a build error for various odd combinations of CONFIG_HOTPLUG
and CONFIG_NET.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Nigel Cunningham <ncunningham@cyclades.com>
Cc: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] sysfs: Allow sysfs attribute files to be pollable

It works like this:
Open the file
Read all the contents.
Call poll requesting POLLERR or POLLPRI (so select/exceptfds works)
When poll returns,
close the file and go to top of loop.
or lseek to start of file and go back to the 'read'.

Events are signaled by an object manager calling
sysfs_notify(kobj, dir, attr);

If the dir is non-NULL, it is used to find a subdirectory which
contains the attribute (presumably created by sysfs_create_group).

This has a cost of one int per attribute, one wait_queuehead per kobject,
one int per open file.

The name "sysfs_notify" may be confused with the inotify
functionality. Maybe it would be nice to support inotify for sysfs
attributes as well?

This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action
to be pollable

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] kobject_add_dir

Adding kobject_add_dir() function which creates a subdirectory
for a given kobject.

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] Kobject: kobject.h: fix a typo

It shouldn't cause real harm, but it hurts my eyes.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Revert mount/umount uevent removal

This change reverts the 033b96fd30db52a710d97b06f87d16fc59fee0f1 commit
from Kay Sievers that removed the mount/umount uevents from the kernel.
Some older versions of HAL still depend on these events to detect when a
new device has been mounted. These events are not correctly emitted,
and are broken by design, and so, should not be relied upon by any
future program. Instead, the /proc/mounts file should be polled to
properly detect this kind of event.

A feature-removal-schedule.txt entry has been added, noting when this
interface will be removed from the kernel.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] kobject_uevent CONFIG_NET=n fix

lib/lib.a(kobject_uevent.o)(.text+0x25f): In function `kobject_uevent':
: undefined reference to `__alloc_skb'
lib/lib.a(kobject_uevent.o)(.text+0x2a1): In function `kobject_uevent':
: undefined reference to `skb_over_panic'
lib/lib.a(kobject_uevent.o)(.text+0x31d): In function `kobject_uevent':
: undefined reference to `skb_over_panic'
lib/lib.a(kobject_uevent.o)(.text+0x356): In function `kobject_uevent':
: undefined reference to `netlink_broadcast'
lib/lib.a(kobject_uevent.o)(.init.text+0x9): In function `kobject_uevent_init':
: undefined reference to `netlink_kernel_create'
make: *** [.tmp_vmlinux1] Error 1

Netlink is unconditionally enabled if CONFIG_NET, so that's OK.

kobject_uevent.o is compiled even if !CONFIG_HOTPLUG, which is lazy.

Let's compound the sin.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] driver core: replace "hotplug" by "uevent"

Leave the overloaded "hotplug" word to susbsystems which are handling
real devices. The driver core does not "plug" anything, it just exports
the state to userspace and generates events.

Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] merge kobject_uevent and kobject_hotplug

The distinction between hotplug and uevent does not make sense these
days, netlink events are the default.

udev depends entirely on netlink uevents. Only during early boot and
in initramfs, /sbin/hotplug is needed. So merge the two functions and
provide only one interface without all the options.

The netlink layer got a nice generic interface with named slots
recently, which is probably a better facility to plug events for
subsystem specific events.
Also the new poll() interface to /proc/mounts is a nicer way to
notify about changes than sending events through the core.
The uevents should only be used for driver core related requests to
userspace now.

Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] remove mount/umount uevents from superblock handling

The names of these events have been confusing from the beginning
on, as they have been more like claim/release events. We needed these
events for noticing HAL if storage devices have been mounted.

Thanks to Al, we have the proper solution now and can poll()
/proc/mounts instead to get notfied about mount tree changes.

Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] remove CONFIG_KOBJECT_UEVENT option

It makes zero sense to have hotplug, but not the netlink
events enabled today. Remove this option and merge the
kobject_uevent.h header into the kobject.h header file.

Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] gfp_t: lib/*

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] kset_hotplug_ops->name shoudl return const char *

kobject: change name() method in kset_hotplug_ops return const char *
since users shoudl not try to modify returned data.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] Make kobject's name be const char *

kobject: make kobject's name const char * since users should not
attempt to change it (except by calling kobject_rename).

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!