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>
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>
No longer fall back to "add" and warn, but always require a valid
action-string written to the "uevent" file.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sysfs is creating several devices in cuse class concurrently and with
CONFIG_SYSFS_DEPRECATED turned off, it triggers the following oops.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
IP: [<ffffffff81158b0a>] sysfs_addrm_start+0x4a/0xf0
PGD 75bb067 PUD 75be067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
last sysfs file: /sys/devices/system/cpu/cpu7/topology/core_siblings
CPU 1
Modules linked in: cuse fuse
Pid: 4737, comm: osspd Not tainted 2.6.31-work #77
RIP: 0010:[<ffffffff81158b0a>] [<ffffffff81158b0a>] sysfs_addrm_start+0x4a/0xf0
RSP: 0018:ffff88000042f8f8 EFLAGS: 00010296
RAX: ffff88000042ffd8 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff880007eef660 RDI: 0000000000000001
RBP: ffff88000042f918 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff81158b0a R12: ffff88000042f928
R13: 00000000fffffff4 R14: 0000000000000000 R15: ffff88000042f9a0
FS: 00007fe93905a950(0000) GS:ffff880008600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000038 CR3: 00000000077c9000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process osspd (pid: 4737, threadinfo ffff88000042e000, task ffff880007eef040)
Stack:
ffff880005da10e8 0000000011cc8d6e ffff88000042f928 ffff880003d28a28
<0> ffff88000042f988 ffffffff811592d7 0000000000000000 0000000000000000
<0> 0000000000000000 0000000000000000 ffff88000042f958 0000000011cc8d6e
Call Trace:
[<ffffffff811592d7>] create_dir+0x67/0xe0
[<ffffffff811593a8>] sysfs_create_dir+0x58/0xb0
[<ffffffff8128ca7c>] ? kobject_add_internal+0xcc/0x220
[<ffffffff812942e1>] ? vsnprintf+0x3c1/0xb90
[<ffffffff8128cab7>] kobject_add_internal+0x107/0x220
[<ffffffff8128cd37>] kobject_add_varg+0x47/0x80
[<ffffffff8128ce53>] kobject_add+0x53/0x90
[<ffffffff81357d84>] device_add+0xd4/0x690
[<ffffffff81356c2b>] ? dev_set_name+0x4b/0x70
[<ffffffffa001a884>] cuse_process_init_reply+0x2b4/0x420 [cuse]
...
The problem is that kobject_add_internal() first adds a kobject to the
kset and then try to create sysfs directory for it. If the creation
fails, it remove the kobject from the kset. get_device_parent()
accesses class_dirs kset while only holding class_dirs.list_lock to
see whether the cuse class dir exists. But when it exists, it may not
have finished initialization yet or may fail and get removed soon. In
the above case, the former happened so the second one ends up trying
to create subdirectory under NULL sysfs_dirent.
Fix it by grabbing a mutex in get_device_parent().
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Colin Guthrie <cguthrie@mandriva.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If device_add() is called with a device which does not have dev->p set
up, then device_private_init() is called. If that succeeds, then the
error variable is set to 0. Now if the dev_name(dev) check further
down fails, then device_add() correctly terminates, but returns 0.
That of course lets the driver progress. If later another driver uses
this half set up device as parent then device_add() of the child
device explodes and renders sysfs completely unusable.
Set the error to -EINVAL if dev_name() check fails.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: "Hans J. Koch" <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Many struct bin_attribute descriptors are purely read-only
structures, and there's no need to change them. Therefore
make the promise not to, which will let those descriptors
be put in a ro section.
Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Most device_attributes are const, and are begging to be
put in a ro section. However, the create and remove
file interfaces were failing to propagate the const promise
which the only functions they call offer.
Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1310) works around a race in dev_driver_string(). If
the device is unbound while the function is running, dev->driver might
become NULL after we test it and before we dereference it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
device_shutdown is defined to just shutdown the hardware and to not
clean up any kernel data structures. Therefore don't put the kobjects
for /sys/dev and /sys/dev/block and /sys/dev/char.
This ensures we don't remove /sys/dev/block and /sys/dev/char while
we still have symlinks from there to the actual devices.
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This allows subsytems to provide devtmpfs with non-default permissions
for the device node. Instead of the default mode of 0600, null, zero,
random, urandom, full, tty, ptmx now have a mode of 0666, which allows
non-privileged processes to access standard device nodes in case no
other userspace process applies the expected permissions.
This also fixes a wrong assignment in pktcdvd and a checkpatch.pl complain.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Devtmpfs lets the kernel create a tmpfs instance called devtmpfs
very early at kernel initialization, before any driver-core device
is registered. Every device with a major/minor will provide a
device node in devtmpfs.
Devtmpfs can be changed and altered by userspace at any time,
and in any way needed - just like today's udev-mounted tmpfs.
Unmodified udev versions will run just fine on top of it, and will
recognize an already existing kernel-created device node and use it.
The default node permissions are root:root 0600. Proper permissions
and user/group ownership, meaningful symlinks, all other policy still
needs to be applied by userspace.
If a node is created by devtmps, devtmpfs will remove the device node
when the device goes away. If the device node was created by
userspace, or the devtmpfs created node was replaced by userspace, it
will no longer be removed by devtmpfs.
If it is requested to auto-mount it, it makes init=/bin/sh work
without any further userspace support. /dev will be fully populated
and dynamic, and always reflect the current device state of the kernel.
With the commonly used dynamic device numbers, it solves the problem
where static devices nodes may point to the wrong devices.
It is intended to make the initial bootup logic simpler and more robust,
by de-coupling the creation of the inital environment, to reliably run
userspace processes, from a complex userspace bootstrap logic to provide
a working /dev.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jan Blunck <jblunck@suse.de>
Tested-By: Harald Hoyer <harald@redhat.com>
Tested-By: Scott James Remnant <scott@ubuntu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Let attribute group vectors be declared "const". We'd
like to let most attribute metadata live in read-only
sections... this is a start.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
No one should directly access the driver_data field, so remove the field
and make it private. We dynamically create the private field now if it
is needed, to handle drivers that call get/set before they are
registered with the driver core.
Also update the copyright notices on these files while we are there.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1271) affects when new devices get linked into their
bus's list of devices. Currently this happens after probing, and it
doesn't happen at all if probing fails. Clearly this is wrong,
because at that point quite a few symbolic links have already been
created in sysfs. We are committed to adding the device, so it should
be linked into the bus's list regardless.
In addition, this needs to happen before the uevent announcing the new
device gets issued. Otherwise user programs might try to access the
device before it has been added to the bus.
To fix both these problems, the patch moves the call to
klist_add_tail() forward from bus_attach_device() to bus_add_device().
Since bus_attach_device() now does nothing but probe for drivers, it
has been renamed to bus_probe_device(). And lastly, the kerneldoc is
updated.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds the nodename callback for struct class, struct device_type and
struct device, to allow drivers to send userspace hints on the device
name and subdirectory that should be used for it.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This removes the
warning: format not a string literal and no format arguments
warnings in the driver core that gcc 4.3.3 complains about.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
A patch series to make .shutdown execute asynchronously. Some drivers's
shutdown can take a lot of time. The patches can help save some shutdown
time. The patches use Arjan's async API.
This patch:
synchronize all tasks submitted by .shutdown
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We also fix a problem with cleaning up properly when initializing
drivers and devices, so checks like this will work successfully.
Portions of the patch by Linus and Greg and Ingo.
Reported-by: Ozan Çağlayan <ozan@pardus.org.tr>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
notice one system /proc/iomem some entries missed the name for pci_devices
it turns that dev->dev.kobj name is changed after device_add.
for pci code: via acpi_pci_root_driver.ops.add (aka acpi_pci_root_add)
==> pci_acpi_scan_root is used to scan pci bus/device, and at the same
time we read the resource for pci_dev in the pci_read_bases, we have
res->name = pci_name(pci_dev); pci_name is calling dev_name.
later via acpi_pci_root_driver.ops.start (aka acpi_pci_root_start) ==>
pci_bus_add_device to add all pci_dev in kobj tree. pci_bus_add_device
will call device_add.
actually in device_add
/* first, register with generic layer. */
error = kobject_add(&dev->kobj, dev->kobj.parent, "%s", dev_name(dev));
if (error)
goto Error;
will get one new name for that kobj, old name is freed.
[Impact: fix corrupted names in /proc/iomem ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Vrabel noticed that the wireless usb stack likes to call
device_for_each_chile() with an empty bus. This used to work fine, but
now oopses. This patch fixes the oops and makes the code behave like it
used to.
Reported-by: David Vrabel <david.vrabel@csr.com>
Tested-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
dpm_list currently relies on the fact that child devices will
be registered after their parents to get a correct suspend
order. Using device_move() however destroys this assumption, as
an already registered device may be moved under a newly registered
one.
This patch adds a new argument to device_move(), allowing callers
to specify how dpm_list should be adapted.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
Nothing outside of the driver core should ever touch klist_children, or
knode_parent, so move them out of the public eye.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is to be used to move things out of struct device that no code
outside of the driver core should ever touch.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
Fix function parameter name in kernel-doc:
Warning(linux-next-20090120//drivers/base/core.c:1289): No description found for parameter 'dev'
Warning(linux-next-20090120//drivers/base/core.c:1289): Excess function parameter 'root' description in 'root_device_unregister'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Commit 3ada8b7e ("block: struct device - replace bus_id with dev_name(),
dev_set_name()") deleted the code in register_disk() that changed a '/'
to a '!' in the device name when registering a disk, but dev_set_name()
does not perform this conversion.
This leads to amusing problems with disks that have '/' in their names:
for example a failure to boot with the root partition on a cciss device,
even though the kernel says it knows about the root device:
VFS: Cannot open root device "cciss/c0d0p6" or unknown-block(0,0)
Please append a correct "root=" boot option; here are the available partitions:
6800 71652960 cciss/c0d0 driver: cciss
6802 1 cciss/c0d0p2
6805 2931831 cciss/c0d0p5
6806 34354908 cciss/c0d0p6
6810 71652960 cciss/c0d1 driver: cciss
Fix this by adding code to change '/' to '!' in dev_set_name() to handle
this until dev_set_name() is converted to use kobject_set_name().
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This reverts commit 2831fe6f9c.
Turns out that device_initialize shouldn't fail silently.
This series needs to be reworked in order to get into proper
shape.
Reported-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This reverts commit 11c3b5c3e0.
Turns out that device_initialize shouldn't fail silently.
This series needs to be reworked in order to get into proper
shape.
Reported-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add support for allocating root device objects which group
device objects under /sys/devices directories.
Also add a sysfs 'module' symlink which points to the owner
of the root device object. This symlink will be used in virtio
to allow userspace to determine which virtio bus implementation
a given device is associated with.
[Includes suggestions from Cornelia Huck]
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1184) changes the location of the notifications in
device_add() and device_del(). Now the BUS_NOTIFY_ADD_DEVICE message
is sent after dpm_sysfs_add(), which is necessary for clients that
want to add attributes to the power/ subdirectory. The
BUS_NOTIFY_DEL_DEVICE message is correspondingly moved before
dpm_sysfs_remove().
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Nothing outside of the driver core should ever touch klist_children, or
knode_parent, so move them out of the public eye.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is to be used to move things out of struct device that no code
outside of the driver core should ever touch.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When looking at kobject_rename I found two bugs with
that exist when sysfs support is disabled in the kernel.
kobject_rename does not change the name on the kobject when
sysfs support is not compiled in.
kobject_rename without locking attempts to check the
validity of a rename operation, which the kobject layer
simply does not have the infrastructure to do.
This patch documents the previously unstated requirement of
kobject_rename that is the responsibility of the caller to
provide mutual exclusion and to be certain that the new_name
for the kobject is valid.
This patch modifies sysfs_rename_dir in !CONFIG_SYSFS case
to call kobject_set_name to actually change the kobject_name.
This patch removes the bogus and misleading check in kobject_rename
that attempts to see if a rename is valid. The check is bogus
because we do not have the proper locking. The check is misleading
because it looks like we can and do perform checking at the kobject
level that we don't.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If device_register() in device_create_vargs() fails, the device
must be cleaned up with put_device() (which is also fine on NULL)
instead of kfree().
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make the comments on how to use device_initialize(), device_add()
and device_register() a bit clearer - in particular, explicitly
note that put_device() must be used once we tried to add the device
to the hierarchy.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Iterating over entries using callback usually isn't too fun especially
when the entry being iterated over can't be manipulated freely. This
patch converts class->p->class_devices to klist and implements class
device iterator so that the users can freely build their own control
structure. The users are also free to call back into class code
without worrying about locking.
class_for_each_device() and class_find_device() are converted to use
the new iterators, so their users don't have to worry about locking
anymore either.
Note: This depends on klist-dont-iterate-over-deleted-entries patch
because class_intf->add/remove_dev() depends on proper synchronization
with device removal.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This gives us a way to handle both the bus_id and init_name values being
used for a while during the transition period.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1124) fixes a couple of bugs in the PM core. The new
dev->power.status field should be initialized regardless of whether
CONFIG_PM_SLEEP is enabled, and similarly dpm_sysfs_add() should be
called whenever CONFIG_PM is enabled.
The patch separates out the call to dpm_sysfs_add() from the call to
device_pm_add(). As a result device_pm_add() can no longer return an
error, so its return type is changed to void.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Romit Dasgupta <romit@ti.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add const markings to dev_name and dev_driver_string to make it clear that
dev_printk doesn't modify dev. This is a prerequisite to adding more
const markings to other functions make it clearer, which functions can
modify dev and which can't.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Use WARN() instead of a printk+WARN_ON() pair; this way the message
becomes part of the warning section for better reporting/collection.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
driver core: Suppress sysfs warnings for device_rename().
Renaming network devices to an already existing name is not
something we want sysfs to print a scary warning for, since the
callers can deal with this correctly. So let's introduce
sysfs_create_link_nowarn() which gets rid of the common warning.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Now that the lockdep infrastructure in the class core is in place, we
should be able to properly change the internal class semaphore to be a
mutex.
David wrote the original patch, and Greg fixed it up to apply properly
due to all of the recent changes in this area.
From: Dave Young <hidave.darkstar@gmail.com>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This renames the struct class "sem" field to be "class_sem" to make
things easier when struct bus_type and struct class merge in the future.
It also makes grepping for fields easier as well.
Based on an idea from Kay.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This renames the struct class "subsys" field to be "class_subsys" to
make things easier when struct bus_type and struct class merge in the
future. It also makes grepping for fields easier as well.
Based on an idea from Kay.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This renames the struct class "interfaces" field to be
"class_interfaces" to make things easier when struct bus_type and struct
class merge in the future. It also makes grepping for fields easier as
well.
Based on an idea from Kay.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This renames the struct class "devices" field to be "class_devices" to
make things easier when struct bus_type and struct class merge in the
future. It also makes grepping for fields easier as well.
Based on an idea from Kay.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This moves the portions of struct class that are dynamic (kobject and
lock and lists) out of the main structure and into a dynamic, private,
structure.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This mirrors the functionality that driver_find_device has as well.
We add a start variable, and all callers of the function are fixed up at
the same time.
The block layer will be using this new functionality in a follow-on
patch.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Now that device_create() has been audited, rename things back to the
original call to be sane.
Keep the device_create_drvdata macro around to make merges easier.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There are no more users of this, and it is racy. Use
device_create_drvdata() or device_create_vargs() instead.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Why?:
There are occasions where userspace would like to access sysfs
attributes for a device but it may not know how sysfs has named the
device or the path. For example what is the sysfs path for
/dev/disk/by-id/ata-ST3160827AS_5MT004CK? With this change a call to
stat(2) returns the major:minor then userspace can see that
/sys/dev/block/8:32 links to /sys/block/sdc.
What are the alternatives?:
1/ Add an ioctl to return the path: Doable, but sysfs is meant to reduce
the need to proliferate ioctl interfaces into the kernel, so this
seems counter productive.
2/ Use udev to create these symlinks: Also doable, but it adds a
udev dependency to utilities that might be running in a limited
environment like an initramfs.
3/ Do a full-tree search of sysfs.
[kay.sievers@vrfy.org: fix duplicate registrations]
[kay.sievers@vrfy.org: cleanup suggestions]
Cc: Neil Brown <neilb@suse.de>
Cc: Tejun Heo <htejun@gmail.com>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Reviewed-by: SL Baur <steve@xemacs.org>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Mark Lord <lkml@rtr.ca>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fix kernel-doc for new dev_set_name() function:
Warning(lin2626-rc5//drivers/base/core.c:767): No description found for parameter 'fmt'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Create the dev_set_name function now so that various subsystems can
start changing over to it before other changes in 2.6.27 will make it
compulsory.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We want to have the drvdata field set properly when creating the device
as sysfs callbacks can assume it is present and it can race the later
setting of this field.
So, create two new functions, deviec_create_vargs() and
device_create_drvdata() that take this new field.
device_create_drvdata() will go away in 2.6.27 as the drvdata field will
just be moved to the device_create() call as it should be.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It is possible that the entry in sysfs already exists, one case of this is
when a network device is renamed to bonding_masters. Anyway, in this case
the proper error path is for device_rename to return an error code, not to
generate bogus backtrace and errors.
Also, to avoid possible races, the create link should be done before the
remove link. This makes a device rename atomic operation like other renames.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
in the device_add, we try to use use parent numa_node.
need to make sure pci root bus's bridge device numa_node is set.
then we could use device->numa_node direclty for all device.
and don't need to call pcibus_to_node().
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-2.6: (36 commits)
SCSI: convert struct class_device to struct device
DRM: remove unused dev_class
IB: rename "dev" to "srp_dev" in srp_host structure
IB: convert struct class_device to struct device
memstick: convert struct class_device to struct device
driver core: replace remaining __FUNCTION__ occurrences
sysfs: refill attribute buffer when reading from offset 0
PM: Remove destroy_suspended_device()
Firmware: add iSCSI iBFT Support
PM: Remove legacy PM (fix)
Kobject: Replace list_for_each() with list_for_each_entry().
SYSFS: Explicitly include required header file slab.h.
Driver core: make device_is_registered() work for class devices
PM: Convert wakeup flag accessors to inline functions
PM: Make wakeup flags available whenever CONFIG_PM is set
PM: Fix misuse of wakeup flag accessors in serial core
Driver core: Call device_pm_add() after bus_add_device() in device_add()
PM: Handle device registrations during suspend/resume
block: send disk "change" event for rescan_partitions()
sysdev: detect multiple driver registrations
...
Fixed trivial conflict in include/linux/memory.h due to semaphore header
file change (made irrelevant by the change to mutex).
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
After 2.6.24 there was a plan to make the PM core acquire all device
semaphores during a suspend/hibernation to protect itself from
concurrent operations involving device objects. That proved to be
too heavy-handed and we found a better way to achieve the goal, but
before it happened, we had introduced the functions
device_pm_schedule_removal() and destroy_suspended_device() to allow
drivers to "safely" destroy a suspended device and we had adapted some
drivers to use them. Now that these functions are no longer necessary,
it seems reasonable to remove them and modify their users to use the
normal device unregistration instead.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Include dpm_sysfs_add() into device_pm_add(), in analogy with
device_pm_remove(), and modify device_add() to call the latter after
bus_add_device(), to avoid situations in which the PM core may
attempt to suspend a device the registration of which has not been
successful.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Modify the PM core to protect its data structures, specifically the
dpm_active list, from being corrupted if a child of the currently
suspending device is registered concurrently with its ->suspend()
callback. In that case, since the new device (the child) is added
to dpm_active after its parent, the PM core will attempt to
suspend it after the parent, which is wrong.
Introduce a new member of struct dev_pm_info, called 'sleeping',
and use it to check if the parent of the device being added to
dpm_active has been suspended, in which case the device registration
fails. Also, use 'sleeping' for checking if the ordering of devices
on dpm_active is correct.
Introduce variable 'all_sleeping' that will be set to 'true' once all
devices have been suspended and make new device registrations fail
until 'all_sleeping' is reset to 'false', in order to avoid having
unsuspended devices around while the system is going into a sleep state.
Remove pm_sleep_rwsem which is not necessary any more.
Special thanks to Alan Stern for discussions and suggestions that
lead to the creation of this patch.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Try to find the culprit who caused
http://bugzilla.kernel.org/show_bug.cgi?id=10150
Cc: <balajirrao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Driver core: Fix cleanup when failing device_add().
- Don't call cleanup_device_parent() if we didn't call setup_parent().
- dev->kobj.parent may be NULL when cleanup_device_parent() is called,
so we need to handle glue_dir == NULL in cleanup_glue_dir().
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Since device_pm_remove(dev) calls dpm_sysfs_remove(dev), it's
incorrect to call the latter after the former in the device_add()
error path.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Driver core: Remove unneeded get_{device,driver}() calls.
Code trying to add/remove attributes must hold a reference to
the device resp. driver anyway, so let's remove those reference
count games.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Convert to use class_find_device api in drivers/base/core.c
Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This fixes up the driver core build errors when CONFIG_BLOCK=N
Thanks to Alexander van Heukelum <heukelum@mailshack.com> for the basis
of this patch, and to Jeremy Fitzhardinge <jeremy@goop.org> for
reporting the problem.
Cc: Alexander van Heukelum <heukelum@mailshack.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fix up a number of coding style issues in the drivers/base/ directory
that have annoyed me over the years. checkpatch.pl is now very happy.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make setup_parent() void as get_device_parent() will always return
either a valid kobject or NULL.
Introduce cleanup_glue_dir() to drop reference grabbed on "glue"
directory by get_device_parent(). Use it for cleanup in device_move()
and device_add() on errors.
This should fix the refcounting problem reported in
http://marc.info/?l=linux-kernel&m=120052487909200&w=2
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Dave Young <hidave.darkstar@gmail.com>
Cc: Gabor Gombas <gombasg@sztaki.hu>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: David Miller <davem@davemloft.net>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
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>
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>
This moves the block devices to /sys/class/block. It will create a
flat list of all block devices, with the disks and partitions in one
directory. For compatibility /sys/block is created and contains symlinks
to the disks.
/sys/class/block
|-- sda -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda
|-- sda1 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1
|-- sda10 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda10
|-- sda5 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5
|-- sda6 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda6
|-- sda7 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda7
|-- sda8 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda8
|-- sda9 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda9
`-- sr0 -> ../../devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sr0
/sys/block/
|-- sda -> ../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda
`-- sr0 -> ../devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sr0
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We should remove the glue directory between the class and the bus
device _after_ we sent out the 'remove' event for the device, otherwise
the parent relationship is no longer valid, and composing the path
with deleted sysfs entries will not work.
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The driver core debugging messages are a mess. This provides a unified
message that makes them actually useful.
The format for new kobject debug messages should be:
driver/bus/class: 'OBJECT_NAME': FUNCTION_NAME: message.\n
Note, the class code is not changed in this patch due to pending patches
in my queue that this would conflict with. A later patch will clean
them up.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
struct bus_type is static everywhere in the kernel. This moves the
kobject in the structure out of it, and a bunch of other private only to
the driver core fields are now moved to a private structure. This lets
us dynamically create the backing kobject properly and gives us the
chance to be able to document to users exactly how to use the struct
bus_type as there are no fields they can improperly access.
Thanks to Kay for the build fixes on this patch.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This converts the code to use the new kobject functions, cleaning up the
logic in doing so.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
device_shutdown does not need to be in a separate file. Move it into
the driver core file where it belongs.
This also moves us one more step closer to making devices_kset static,
now only the crazy sysdevs are keeping that from happening...
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Dynamically create the kset instead of declaring it statically. We also
rename devices_subsys to devices_kset to catch all users of the
variable.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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_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>
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>
This patch reorganizes the way suspend and resume notifications are
sent to drivers. The major changes are that now the PM core acquires
every device semaphore before calling the methods, and calls to
device_add() during suspends will fail, while calls to device_del()
during suspends will block.
It also provides a way to safely remove a suspended device with the
help of the PM core, by using the device_pm_schedule_removal() callback
introduced specifically for this purpose, and updates two drivers (msr
and cpuid) that need to use it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The CONFIG_SUSPEND changes in 2.6.23 caused a regression under certain
configuration conditions (SUSPEND=n, USB_AUTOSUSPEND=y) where all USB
device attributes in sysfs (idVendor, idProduct, ...) silently disappeared,
causing udev breakage and more.
The cause of this is that the /sys/.../power subdirectory is now only
created when CONFIG_PM_SLEEP is set, however, it should be created whenever
CONFIG_PM is set to handle the above situation. The following patch fixes
the regression.
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This should fix the sysfs warnings that renaming network devices is
causing to show up with CONFIG_SYSFS_DEPRECATED=y
The code just shouldn't run if class devices are real directories, it's
an update for the symlink in the class directory. Nobody noticed that as
long as the creation of sysfs files silently failed, and we both missed
it before the merge, because we don't run SYSFS_DEPRECATED=y.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: David Miller <davem@davemloft.net>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This makes it a bit more sane when trying to figure out how to clean up
the ktype mess.
Based on a larger patch from Kay Sievers
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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>
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>
We should only reparent to a class former class devices that
form the base of class hierarchy. Nested devices should still
grow from their real parents.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Tested-by: Andrey Borzenkov <arvidjaar@mail.ru>
Tested-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As Stephen Hemminger says, this is a "belt and suspenders" patch that
zeroes the envp array at allocation time, even though all the users
should NULL-terminate it anyway (and we've hopefully fixed everybody
that doesn't do that).
And we'll apparently clean the whole envp thing up for 2.6.24 anyway.
But let's just be robust, and do both this *and* make sure that all
users are doing the right thing.
Acked-by: Stephen Hemminger <shemminger@linux-foundation.org>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nested class devices used to have 'device' symlink point to a real
(physical) device instead of a parent class device. When converting
subsystems to struct device we need to keep doing what class devices did if
CONFIG_SYSFS_DEPRECATED is Y, otherwise parts of udev break.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Greg KH <greg@kroah.com>
Tested-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
driver core: revert "device" link creation check
Commit 2ee97caf0a introduced an extra
check on when to create the "device" symlink. Unfortunately, this
breaks input, so let's revert to the old behaviour.
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>
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>
Check for return value of sysfs_create_link() in device_add() and
device_rename(). Add helper functions device_add_class_symlinks() and
device_remove_class_symlinks() to make the code easier to read.
[akpm@linux-foundation.org: fix unused var warnings]
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
