The pre-existing sysfs interfaces which take explicit namespace
argument are weird in that they place the optional @ns in front of
@name which is contrary to the established convention. For example,
we end up forcing vast majority of sysfs_get_dirent() users to do
sysfs_get_dirent(parent, NULL, name), which is silly and error-prone
especially as @ns and @name may be interchanged without causing
compilation warning.
This renames sysfs_get_dirent() to sysfs_get_dirent_ns() and swap the
positions of @name and @ns, and sysfs_get_dirent() is now a wrapper
around sysfs_get_dirent_ns(). This makes confusions a lot less
likely.
There are other interfaces which take @ns before @name. They'll be
updated by following patches.
This patch doesn't introduce any functional changes.
v2: EXPORT_SYMBOL_GPL() wasn't updated leading to undefined symbol
error on module builds. Reported by build test robot. Fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There's no reason for sysfs to be calling ktype->namespace(). It is
backwards, obfuscates what's going on and unnecessarily tangles two
separate layers.
There are two places where symlink code calls ktype->namespace().
* sysfs_do_create_link_sd() calls it to find out the namespace tag of
the target directory. Unless symlinking races with cross-namespace
renaming, this equals @target_sd->s_ns.
* sysfs_rename_link() uses it to find out the new namespace to rename
to and the new namespace can be different from the existing one.
The function is renamed to sysfs_rename_link_ns() with an explicit
@ns argument and the ktype->namespace() invocation is shifted to the
device layer.
While this patch replaces ktype->namespace() invocation with the
recorded result in @target_sd, this shouldn't result in any behvior
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>
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>
sysfs ns (namespace) implementation became more convoluted than
necessary while trying to hide ns information from visible interface.
The relatively recent attr ns support is a good example.
* attr ns tag is determined by sysfs_ops->namespace() callback while
dir tag is determined by kobj_type->namespace(). The placement is
arbitrary.
* Instead of performing operations with explicit ns tag, the namespace
callback is routed through sysfs_attr_ns(), sysfs_ops->namespace(),
class_attr_namespace(), class_attr->namespace(). It's not simpler
in any sense. The only thing this convolution does is traversing
the whole stack backwards.
The namespace callbacks are unncessary because the operations involved
are inherently synchronous. The information can be provided in in
straight-forward top-down direction and reversing that direction is
unnecessary and against basic design principles.
This backward interface is unnecessarily convoluted and hinders
properly separating out sysfs from driver model / kobject for proper
layering. This patch updates attr ns support such that
* sysfs_ops->namespace() and class_attr->namespace() are dropped.
* sysfs_{create|remove}_file_ns(), which take explicit @ns param, are
added and sysfs_{create|remove}_file() are now simple wrappers
around the ns aware functions.
* ns handling is dropped from sysfs_chmod_file(). Nobody uses it at
this point. sysfs_chmod_file_ns() can be added later if necessary.
* Explicit @ns is propagated through class_{create|remove}_file_ns()
and netdev_class_{create|remove}_file_ns().
* driver/net/bonding which is currently the only user of attr
namespace is updated to use netdev_class_{create|remove}_file_ns()
with @bh->net as the ns tag instead of using the namespace callback.
This patch should be an equivalent conversion without any functional
difference. It makes the code easier to follow, reduces lines of code
a bit and helps proper separation and layering.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kay Sievers <kay@vrfy.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When I included the "empty" function for sysfs_create_groups() when
CONFIG_SYSFS=n, I forgot to return a value for it, so things blew up the
build. This patch fixes that, stupid me.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This creates the macro __ATTR_WO() for write-only attributes, instead of
having to "open define" them.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Gotta love a macro that doesn't reduce the typing you have to do.
Also, only the driver core, and one network driver uses this. The
driver core functions will be going away soon, and I'll convert the
network driver soon to not need this as well, so delete it for now
before anyone else gets some bright ideas and wants to use it.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As long as we are cleaning up sysfs coding style issues, don't forget
the main sysfs.h file, so fix up the space issues there as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These functions are being open-coded in 3 different places in the driver
core, and other driver subsystems will want to start doing this as well,
so move it to the sysfs core to keep it all in one place, where we know
it is written properly.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
__BIN_ATTR_RW() wasn't passing in the _size field. As it would break
the build if this macro was ever used, it's obvious no one had ever
tried to use it before.
Fix it so that it can be used.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With the last patches stat.h was included to the header, and thus those
permission defines should be used.
Signed-off-by: Oliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With the recent changes to sysfs there's various helper macro's.
However there's no RW, RO BIN_ helper macro's. This patch adds them.
Signed-off-by: Oliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
groups should be able to support binary attributes, just like it
supports "normal" attributes. This lets us only handle one type of
structure, groups, throughout the driver core and subsystems, making
binary attributes a "full fledged" part of the driver model, and not
something just "tacked on".
Reported-by: Oliver Schinagl <oliver@schinagl.nl>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This makes it easier to create static binary attributes, which is needed
in a number of drivers, instead of "open coding" them.
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To make it easier for driver subsystems to work with attribute groups,
create the ATTRIBUTE_GROUPS macro to remove some of the repetitive
typing for the most common use for attribute groups.
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A number of parts of the kernel created their own version of this, might
as well have the sysfs core provide it instead.
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The most convenient way to expose ACPI power resources lists of a
device is to put symbolic links to sysfs directories representing
those resources into special attribute groups in the device's sysfs
directory. For this purpose, it is necessary to be able to add
symbolic links to attribute groups.
For this reason, add sysfs helper functions for adding/removing
symbolic links to/from attribute groups, sysfs_add_link_to_group()
and sysfs_remove_link_from_group(), respectively.
This change set includes a build fix from David Rientjes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch (as1554) fixes a lockdep false-positive report. The
problem arises because lockdep is unable to deal with the
tree-structured locks created by the device core and sysfs.
This particular problem involves a sysfs attribute method that
unregisters itself, not from the device it was called for, but from a
descendant device. Lockdep doesn't understand the distinction and
reports a possible deadlock, even though the operation is safe.
This is the sort of thing that would normally be handled by using a
nested lock annotation; unfortunately it's not feasible to do that
here. There's no sensible way to tell sysfs when attribute removal
occurs in the context of a parent attribute method.
As a workaround, the patch adds a new flag to struct attribute
telling sysfs not to inform lockdep when it acquires a readlock on a
sysfs_dirent instance for the attribute. The readlock is still
acquired, but lockdep doesn't know about it and hence does not
complain about impossible deadlock scenarios.
Also added are macros for static initialization of attribute
structures with the ignore_lockdep flag set. The three offending
attributes in the USB subsystem are converted to use the new macros.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Tejun Heo <tj@kernel.org>
CC: Eric W. Biederman <ebiederm@xmission.com>
CC: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Looking up files in sysfs is hard to understand and analyize because we
currently allow placing untagged files in tagged directories. In the
implementation of that we have two subtly different meanings of NULL.
NULL meaning there is no tag on a directory entry and NULL meaning
we don't care which namespace the lookup is performed for. This
multiple uses of NULL have resulted in subtle bugs (since fixed)
in the code.
Currently it is only the bonding driver that needs to have an untagged
file in a tagged directory.
To untagle this mess I am adding support for tagged files to sysfs.
Modifying the bonding driver to implement bonding_masters as a tagged
file. Registering bonding_masters once for each network namespace.
Then I am removing support for untagged entries in tagged sysfs
directories.
Resulting in code that is much easier to reason about.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
* new refcount in struct net, controlling actual freeing of the memory
* new method in kobj_ns_type_operations (->drop_ns())
* ->current_ns() semantics change - it's supposed to be followed by
corresponding ->drop_ns(). For struct net in case of CONFIG_NET_NS it bumps
the new refcount; net_drop_ns() decrements it and calls net_free() if the
last reference has been dropped. Method renamed to ->grab_current_ns().
* old net_free() callers call net_drop_ns() instead.
* sysfs_exit_ns() is gone, along with a large part of callchain
leading to it; now that the references stored in ->ns[...] stay valid we
do not need to hunt them down and replace them with NULL. That fixes
problems in sysfs_lookup() and sysfs_readdir(), along with getting rid
of sb->s_instances abuse.
Note that struct net *shutdown* logics has not changed - net_cleanup()
is called exactly when it used to be called. The only thing postponed by
having a sysfs instance refering to that struct net is actual freeing of
memory occupied by struct net.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
