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* kernfs: s/sysfs/kernfs/ in constantsTejun Heo2013-12-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | 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_DIR/KERNFS_DIR/ * s/SYSFS_KOBJ_ATTR/KERNFS_FILE/ * s/SYSFS_KOBJ_LINK/KERNFS_LINK/ * s/SYSFS_{TYPE_FLAGS}/KERNFS_{TYPE_FLAGS}/ * s/SYSFS_FLAG_{FLAG}/KERNFS_{FLAG}/ * s/sysfs_type()/kernfs_type()/ * s/SD_DEACTIVATED_BIAS/KN_DEACTIVATED_BIAS/ This patch is strictly rename only and doesn't introduce any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* kernfs: drop s_ prefix from kernfs_node membersTejun Heo2013-12-111-3/+3
| | | | | | | | | | | | | | | | | 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. s_ prefix for kernfs members is used inconsistently and a misnomer now. It's not like kernfs_node is used widely across the kernel making the ability to grep for the members particularly useful. Let's just drop the prefix. This patch is strictly rename only and doesn't introduce any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* kernfs: s/sysfs_dirent/kernfs_node/ and rename its friends accordinglyTejun Heo2013-12-111-36/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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, kernfs: implement kernfs_ns_enabled()Tejun Heo2013-11-291-1/+1
| | | | | | | | | | | | | | | fs/sysfs/symlink.c::sysfs_delete_link() tests @sd->s_flags for SYSFS_FLAG_NS. Let's add kernfs_ns_enabled() so that sysfs doesn't have to test sysfs_dirent flag directly. This makes things tidier for kernfs proper too. This is purely cosmetic. v2: To avoid possible NULL deref, use noop dummy implementation which always returns false when !CONFIG_SYSFS. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs, kernfs: introduce sysfs_root_sdTejun Heo2013-11-291-3/+3
| | | | | | | | | | | | | Currently, it's assumed that there's a single kernfs hierarchy in the system anchored at sysfs_root which is defined as a global struct. To allow other users of kernfs, this will be made dynamic. Introduce a new global variable sysfs_root_sd which points to &sysfs_root and convert all &sysfs_root users. This patch doesn't introduce any behavior difference. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs, kernfs: move symlink core code to fs/kernfs/symlink.cTejun Heo2013-11-291-137/+0
| | | | | | | | | | | | Move core symlink code to fs/kernfs/symlink.c. fs/sysfs/symlink.c now only contains sysfs wrappers around kernfs interfaces. The respective declarations in fs/sysfs/sysfs.h are moved to fs/kernfs/kernfs-internal.h. This is pure relocation. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs, kernfs: introduce kernfs[_find_and]_get() and kernfs_put()Tejun Heo2013-11-291-7/+9
| | | | | | | | | | | | | | | | | | | | | | | Introduce kernfs interface for finding, getting and putting sysfs_dirents. * sysfs_find_dirent() is renamed to kernfs_find_ns() and lockdep assertion for sysfs_mutex is added. * sysfs_get_dirent_ns() is renamed to kernfs_find_and_get(). * Macro inline dancing around __sysfs_get/put() are removed and kernfs_get/put() are made proper functions implemented in fs/sysfs/dir.c. While the conversions are mostly equivalent, there's one difference - kernfs_get() doesn't return the input param as its return value. This change is intentional. While passing through the input increases writability in some areas, it is unnecessary and has been shown to cause confusion regarding how the last ref is handled. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs, kernfs: remove sysfs_add_one()Tejun Heo2013-11-291-1/+1
| | | | | | | | | | | | | | sysfs_add_one() is a wrapper around __sysfs_add_one() which prints out duplicate name warning if __sysfs_add_one() fails with -EEXIST. The previous kernfs conversions moved all dup warnings to sysfs interface functions and sysfs_add_one() doesn't have any user left. Remove sysfs_add_one() and update __sysfs_add_one() to take its name. This patch doesn't make any functional changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs, kernfs: replace sysfs_dirent->s_dir.kobj and ->s_attr.[bin_]attr with ↵Tejun Heo2013-11-291-1/+1
| | | | | | | | | | | | | | | | | | | | | ->priv A directory sysfs_dirent points to the associated kobj. A regular or bin file points to the associated [bin_]attribute. This patch replaces sysfs_dirent->s_dir.kobj and ->s_attr.[bin_]attr with void * ->priv. This is to prepare for kernfs interface so that sysfs can specify the private data in the same way for directories and files. This lower debuggability but not by much - the whole thing was overlaid in a union anyway. If debuggability becomes an issue, we can later add ->priv accessors which explicitly check for the sysfs_dirent type and performs casting. This patch doesn't introduce any behavior difference. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs, kernfs: introduce kernfs_rename[_ns]()Tejun Heo2013-11-271-1/+1
| | | | | | | | | | | | | Introduce kernfs rename interface, krenfs_rename[_ns](). This is just rename of sysfs_rename(). No functional changes. Function comment is added to kernfs_rename_ns() and @new_parent_sd is renamed to @new_parent for consistency with other kernfs interfaces. v2: Dummy implementation for !CONFIG_SYSFS updated to return -ENOSYS. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs, kernfs: introduce kernfs_create_link()Tejun Heo2013-11-271-30/+46
| | | | | | | | | | | | | | Separate out kernfs symlink interface - kernfs_create_link() - which takes and returns sysfs_dirents, from sysfs_do_create_link_sd(). sysfs_do_create_link_sd() now just determines the parent and target sysfs_dirents and invokes the new interface and handles dup warning. This patch doesn't introduce behavior changes. v2: Dummy implementation for !CONFIG_SYSFS updated to return -ENOSYS. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs, kernfs: introduce kernfs_remove[_by_name[_ns]]()Tejun Heo2013-11-271-2/+2
| | | | | | | | | | | | | | Introduce kernfs removal interfaces - kernfs_remove() and kernfs_remove_by_name[_ns](). These are just renames of sysfs_remove() and sysfs_hash_and_remove(). No functional changes. v2: Dummy kernfs_remove_by_name_ns() for !CONFIG_SYSFS updated to return -ENOSYS instead of 0. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs: drop kobj_ns_type handling, take #2Tejun Heo2013-11-271-20/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The way namespace tags are implemented in sysfs is more complicated than necessary. As each tag is a pointer value and required to be non-NULL under a namespace enabled parent, there's no need to record separately what type each tag is. If multiple namespace types are needed, which currently aren't, we can simply compare the tag to a set of allowed tags in the superblock assuming that the tags, being pointers, won't have the same value across multiple types. This patch rips out kobj_ns_type handling from sysfs. sysfs now has an enable switch to turn on namespace under a node. If enabled, all children are required to have non-NULL namespace tags and filtered against the super_block's tag. kobject namespace determination is now performed in lib/kobject.c::create_dir() making sysfs_read_ns_type() unnecessary. The sanity checks are also moved. create_dir() is restructured to ease such addition. This removes most kobject namespace knowledge from sysfs proper which will enable proper separation and layering of sysfs. This is the second try. The first one was cb26a311578e ("sysfs: drop kobj_ns_type handling") which tried to automatically enable namespace if there are children with non-NULL namespace tags; however, it was broken for symlinks as they should inherit the target's tag iff namespace is enabled in the parent. This led to namespace filtering enabled incorrectly for wireless net class devices through phy80211 symlinks and thus network configuration failure. a1212d278c05 ("Revert "sysfs: drop kobj_ns_type handling"") reverted the commit. This shouldn't introduce any behavior changes, for real. v2: Dummy implementation of sysfs_enable_ns() for !CONFIG_SYSFS was missing and caused build failure. Reported by kbuild test robot. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Kay Sievers <kay@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Revert "sysfs: drop kobj_ns_type handling"Linus Torvalds2013-11-071-6/+21
| | | | | | | | | | | | | | This reverts commit cb26a311578e67769e92a39a0a63476533cb7e12. It mysteriously causes NetworkManager to not find the wireless device for me. As far as I can tell, Tejun *meant* for this commit to not make any semantic changes, but there clearly are some. So revert it, taking into account some of the calling convention changes that happened in this area in subsequent commits. Cc: Tejun Heo <tj@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sysfs: rename sysfs_assoc_lock and explain what it's aboutTejun Heo2013-11-011-6/+14
| | | | | | | | | | | | | | | | | | | | | | sysfs_assoc_lock is an odd piece of locking. In general, whoever owns a kobject is responsible for synchronizing sysfs operations and sysfs proper assumes that, for example, removal won't race with any other operation; however, this doesn't work for symlinking because an entity performing symlink doesn't usually own the target kobject and thus has no control over its removal. sysfs_assoc_lock synchronizes symlink operations against kobj->sd disassociation so that symlink code doesn't end up dereferencing already freed sysfs_dirent by racing with removal of the target kobject. This is quite obscure and the generic name of the lock and lack of comments make it difficult to understand its role. Let's rename it to sysfs_symlink_target_lock and add comments explaining what's going on. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs: remove sysfs_addrm_cxt->parent_sdTejun Heo2013-10-031-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | sysfs_addrm_start/finish() enclose sysfs_dirent additions and deletions and sysfs_addrm_cxt is used to record information necessary to finish the operations. Currently, sysfs_addrm_start() takes @parent_sd, records it in sysfs_addrm_cxt, and assumes that all operations in the block are performed under that @parent_sd. This assumption has been fine until now but we want to make some operations behave recursively and, while having @parent_sd recorded in sysfs_addrm_cxt doesn't necessarily prevents that, it becomes confusing. This patch removes sysfs_addrm_cxt->parent_sd and makes sysfs_add_one() take an explicit @parent_sd parameter. Note that sysfs_remove_one() doesn't need the extra argument as its parent is always known from the target @sd. While at it, add __acquires/releases() notations to sysfs_addrm_start/finish() respectively. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs: @name comes before @nsTejun Heo2013-09-261-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | Some internal sysfs functions 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. This is confusing and error-prone especially as @ns and @name may be interchanged without causing compilation warning. Swap the positions of @name and @ns in the following internal functions. sysfs_find_dirent() sysfs_rename() sysfs_hash_and_remove() sysfs_name_hash() sysfs_name_compare() create_dir() This patch doesn't introduce any functional changes. 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: clean up sysfs_get_dirent()Tejun Heo2013-09-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* sysfs: drop kobj_ns_type handlingTejun Heo2013-09-261-21/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The way namespace tags are implemented in sysfs is more complicated than necessary. As each tag is a pointer value and required to be non-NULL under a namespace enabled parent, there's no need to record separately what type each tag is or where namespace is enabled. If multiple namespace types are needed, which currently aren't, we can simply compare the tag to a set of allowed tags in the superblock assuming that the tags, being pointers, won't have the same value across multiple types. Also, whether to filter by namespace tag or not can be trivially determined by whether the node has any tagged children or not. This patch rips out kobj_ns_type handling from sysfs. sysfs no longer cares whether specific type of namespace is enabled or not. If a sysfs_dirent has a non-NULL tag, the parent is marked as needing namespace filtering and the value is tested against the allowed set of tags for the superblock (currently only one but increasing this number isn't difficult) and the sysfs_dirent is ignored if it doesn't match. This removes most kobject namespace knowledge from sysfs proper which will enable proper separation and layering of sysfs. The namespace sanity checks in fs/sysfs/dir.c are replaced by the new sanity check in kobject_namespace(). As this is the only place ktype->namespace() is called for sysfs, this doesn't weaken the sanity check significantly. I omitted converting the sanity check in sysfs_do_create_link_sd(). While the check can be shifted to upper layer, mistakes there are well contained and should be easily visible anyway. 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: remove ktype->namespace() invocations in symlink codeTejun Heo2013-09-261-9/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* sysfs: fix up 80 column coding style issuesGreg Kroah-Hartman2013-08-211-1/+2
| | | | | | This fixes up the 80 column coding style issues in the sysfs .c files. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs: fix up space coding style issuesGreg Kroah-Hartman2013-08-211-2/+2
| | | | | | | This fixes up all of the space-related coding style issues for the sysfs code. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs: remove trailing whitespaceGreg Kroah-Hartman2013-08-211-1/+1
| | | | | | This removes all trailing whitespace errors in the sysfs code. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs: fix placement of EXPORT_SYMBOL()Greg Kroah-Hartman2013-08-211-6/+3
| | | | | | | The export should happen after the function, not at the bottom of the file, so fix that up. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs: Functions for adding/removing symlinks to/from attribute groupsRafael J. Wysocki2013-01-251-13/+32
| | | | | | | | | | | | | | | | | 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>
* sysfs: Fix comment typo "sysf_create_link".Robert P. J. Day2012-09-041-1/+1
| | | | | | | More pedantry. Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs: allow creating symlinks from untagged to tagged directoriesEric W. Biederman2010-07-261-1/+2
| | | | | | | | | | Supporting symlinks from untagged to tagged directories is reasonable, and needed to support CONFIG_SYSFS_DEPRECATED. So don't fail a prior allowing that case to work. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: sysfs_delete_link handle symlinks from untagged to tagged directories.Eric W. Biederman2010-07-261-1/+1
| | | | | | | | This happens for network devices when SYSFS_DEPRECATED is enabled. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Don't allow the creation of symlinks we can't removeEric W. Biederman2010-07-261-5/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | Recently my tagged sysfs support revealed a flaw in the device core that a few rare drivers are running into such that we don't always put network devices in a class subdirectory named net/. Since we are not creating the class directory the network devices wind up in a non-tagged directory, but the symlinks to the network devices from /sys/class/net are in a tagged directory. All of which works until we go to remove or rename the symlink. When we remove or rename a symlink we look in the namespace of the target of the symlink. Since the target of the symlink is in a non-tagged sysfs directory we don't have a namespace to look in, and we fail to remove the symlink. Detect this problem up front and simply don't create symlinks we won't be able to remove later. This prevents symlink leakage and fails in a much clearer and more understandable way. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Maciej W. Rozycki <macro@linux-mips.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Implement sysfs_delete_linkEric W. Biederman2010-05-211-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | When removing a symlink sysfs_remove_link does not provide enough information to figure out which tagged directory the symlink falls in. So I need sysfs_delete_link which is passed the target of the symlink to delete. sysfs_rename_link is updated to call sysfs_delete_link instead of sysfs_remove_link as we have all of the information necessary and the callers are interesting. Both of these functions now have enough information to find a symlink in a tagged directory. The only restriction is that they must be called before the target kobject is renamed or deleted. If they are called later I loose track of which tag the target kobject was marked with and can no longer find the old symlink to remove it. This patch was split from an earlier patch. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Implement sysfs tagged directory support.Eric W. Biederman2010-05-211-3/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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/*, /sys/devices/virtual/net/*, and potentially a few other directories of the form /sys/ ... /net/*. What this patch does is to add an additional tag field to the sysfs dirent structure. For directories that should show different contents depending on the context such as /sys/class/net/, and /sys/devices/virtual/net/ this tag field is used to specify the context in which those directories should be visible. Effectively this is the same as creating multiple distinct directories with the same name but internally to sysfs the result is nicer. I am calling the concept of a single directory that looks like multiple directories all at the same path in the filesystem tagged directories. For the networking namespace the set of directories whose contents I need to filter with tags can depend on the presence or absence of hotplug hardware or which modules are currently loaded. Which means I need a simple race free way to setup those directories as tagged. To achieve a reace free design all tagged directories are created and managed by sysfs itself. Users of this interface: - define a type in the sysfs_tag_type enumeration. - call sysfs_register_ns_types with the type and it's operations - sysfs_exit_ns when an individual tag is no longer valid - Implement mount_ns() which returns the ns of the calling process so we can attach it to a sysfs superblock. - Implement ktype.namespace() which returns the ns of a syfs kobject. Everything else is left up to sysfs and the driver layer. For the network namespace mount_ns and namespace() are essentially one line functions, and look to remain that. Tags are currently represented a const void * pointers as that is both generic, prevides enough information for equality comparisons, and is trivial to create for current users, as it is just the existing namespace pointer. The work needed in sysfs is more extensive. At each directory or symlink creating I need to check if the directory it is being created in is a tagged directory and if so generate the appropriate tag to place on the sysfs_dirent. Likewise at each symlink or directory removal I need to check if the sysfs directory it is being removed from is a tagged directory and if so figure out which tag goes along with the name I am deleting. Currently only directories which hold kobjects, and symlinks are supported. There is not enough information in the current file attribute interfaces to give us anything to discriminate on which makes it useless, and there are no potential users which makes it an uninteresting problem to solve. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* bridge: update sysfs link names if port device names have changedSimon Arlott2010-05-151-0/+1
| | | | | | | | | | | | | | | | | | | | | Links for each port are created in sysfs using the device name, but this could be changed after being added to the bridge. As well as being unable to remove interfaces after this occurs (because userspace tools don't recognise the new name, and the kernel won't recognise the old name), adding another interface with the old name to the bridge will cause an error trying to create the sysfs link. This fixes the problem by listening for NETDEV_CHANGENAME notifications and renaming the link. https://bugzilla.kernel.org/show_bug.cgi?id=12743 Signed-off-by: Simon Arlott <simon@fire.lp0.eu> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* sysfs: Implement sysfs_rename_linkEric W. Biederman2010-03-071-0/+38
| | | | | | | | | | | | | | | Because of rename ordering problems we occassionally give false warnings about invalid sysfs operations. So using sysfs_rename create a sysfs_rename_link function that doesn't need strange workarounds. Cc: Benjamin Thery <benjamin.thery@bull.net> Cc: Daniel Lezcano <dlezcano@fr.ibm.com> Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Implement sysfs_getattr & sysfs_permissionEric W. Biederman2009-12-111-0/+3
| | | | | | | | | | | | | | | | | With the implementation of sysfs_getattr and sysfs_permission sysfs becomes able to lazily propogate inode attribute changes from the sysfs_dirents to the vfs inodes. This paves the way for deleting significant chunks of now unnecessary code. While doing this we did not reference sysfs_setattr from sysfs_symlink_inode_operations so I added along with sysfs_getattr and sysfs_permission. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Nicely indent sysfs_symlink_inode_operationsEric W. Biederman2009-12-111-4/+4
| | | | | | | | | | | | Lining up the functions in sysfs_symlink_inode_operations follows the pattern in the rest of sysfs and makes things slightly more readable. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: Add labeling support for sysfsDavid P. Quigley2009-09-101-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a setxattr handler to the file, directory, and symlink inode_operations structures for sysfs. The patch uses hooks introduced in the previous patch to handle the getting and setting of security information for the sysfs inodes. As was suggested by Eric Biederman the struct iattr in the sysfs_dirent structure has been replaced by a structure which contains the iattr, secdata and secdata length to allow the changes to persist in the event that the inode representing the sysfs_dirent is evicted. Because sysfs only stores this information when a change is made all the optional data is moved into one dynamically allocated field. This patch addresses an issue where SELinux was denying virtd access to the PCI configuration entries in sysfs. The lack of setxattr handlers for sysfs required that a single label be assigned to all entries in sysfs. Granting virtd access to every entry in sysfs is not an acceptable solution so fine grained labeling of sysfs is required such that individual entries can be labeled appropriately. [sds: Fixed compile-time warnings, coding style, and setting of inode security init flags.] Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* Sysfs: fix possible memleak in sysfs_follow_linkArmin Kuster2009-06-151-1/+4
| | | | | | | | | There is the possiblity of a memory leak if a page is allocated and if sysfs_getlink() fails in the sysfs_follow_link. Signed-off-by: Armin Kuster <akuster@mvista.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* driver core: Suppress sysfs warnings for device_rename().Cornelia Huck2008-07-211-8/+33
| | | | | | | | | | | | | 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>
* sysfs: Allow removal of symlinks in the sysfs rootMark Fasheh2008-04-181-1/+8
| | | | | | | | | | Allow callers of sysfs_remove_link() to pass a NULL kobj, in which case sysfs_root will be used as the parent directory. This allows us to tear down top level symlinks created via sysfs_create_link(), which already has similar handling of a NULL parent object. Signed-off-by: Mark Fasheh <mfasheh@suse.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: create optimal relative symlink targetsKay Sievers2008-01-241-46/+42
| | | | | | | | | | | | | | | | | | | | | | Instead of walking from the source down to the root of sysfs, and back to the target, we stop at the first directory the source and the target share. This link: /devices/pci0000:00/0000:00:1d.7/usb1/1-0:1.0/ep_81 pointed to: ../../../../../devices/pci0000:00/0000:00:1d.0/usb2/2-0:1.0/usb_endpoint/usbdev2.1_ep81 now it just points to: usb_endpoint/usbdev1.1_ep81 Thanks to Denis Cheng for bringing this up, and sending the initial patch. CC: Denis Cheng <crquan@gmail.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: add copyrightsTejun Heo2007-10-121-1/+9
| | | | | | | | | Sysfs has gone through considerable amount of reimplementation. Add copyrights. Any objections? :-) Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: make s_elem an anonymous unionTejun Heo2007-10-121-2/+2
| | | | | | | | | | Make s_elem an anonymous union. Prefixing with s_elem makes things needlessly longer without any advantage. 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>
* sysfs: Make sysfs_mount staticEric W. Biederman2007-10-121-4/+3
| | | | | | | | | | | | | | | This patch modifies the users of sysfs_mount to use sysfs_root instead (which is what they are looking for). It then makes sysfs_mount static to keep people from using it by accident. The net result is slightly faster and cleaner code. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: make sysfs_add_one() automatically check for duplicate entryTejun Heo2007-10-121-6/+3
| | | | | | | | | | | | Make sysfs_add_one() check for duplicate entry and return -EEXIST if such entry exists. This simplifies node addition code a bit. This patch doesn't introduce any noticeable behavior change. 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>
* sysfs: make sysfs_add/remove_one() call link/unlink_sibling() implictlyTejun Heo2007-10-121-3/+1
| | | | | | | | | | | | | | | | | When adding or removing a sysfs_dirent, the user used to be required to call link/unlink separately. It was for two reasons - code looked like that before sysfs_addrm_cxt conversion and to avoid looping through parent_sd->children list twice during removal. Performance optimization during removal just isn't worth it. Make sysfs_add/remove_one() call sysfs_link/unlink_sibing() implicitly. This makes code simpler albeit slightly less efficient. This change doesn't introduce any noticeable behavior change. 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>
* sysfs: cleanup semaphore.hDave Young2007-10-121-1/+1
| | | | | | | | | Cleanup semaphore.h Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: cosmetic clean up on node creation failure pathsTejun Heo2007-07-181-4/+6
| | | | | | | | | | | | | | | | | | | | | | Node addition failure is detected by testing return value of sysfs_addfm_finish() which returns the number of added and removed nodes. As the function is called as the last step of addition right on top of error handling block, the if blocks looked like the following. if (sysfs_addrm_finish(&acxt)) success handling, usually return; /* fall through to error handling */ This is the opposite of usual convention in sysfs and makes the code difficult to understand. This patch inverts the test and makes those blocks look more like others. Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Gabriel C <nix.or.die@googlemail.com> Cc: Miles Lane <miles.lane@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: kill an extra put in sysfs_create_link() failure pathTejun Heo2007-07-181-0/+2
| | | | | | | | | | | | | | | | There is a subtle bug in sysfs_create_link() failure path. When symlink creation fails because there's already a node with the same name, the target sysfs_dirent is put twice - once by failure path of sysfs_create_link() and once more when the symlink is released. Fix it by making only the symlink node responsible for putting target_sd. Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Gabriel C <nix.or.die@googlemail.com> Cc: Miles Lane <miles.lane@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* sysfs: restructure add/remove paths and fix inode updateTejun Heo2007-07-111-9/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The original add/remove code had the following problems. * parent's timestamps are updated on dentry instantiation. this is incorrect with reclaimable files. * updating parent's timestamps isn't synchronized. * parent nlink update assumes the inode is accessible which won't be true once directory dentries are made reclaimable. This patch restructures add/remove paths to resolve the above problems. Add/removal are done in the following steps. 1. sysfs_addrm_start() : acquire locks including sysfs_mutex and other resources. 2-a. sysfs_add_one() : add new sd. linking the new sd into the children list is caller's responsibility. 2-b. sysfs_remove_one() : remove a sd. unlinking the sd from the children list is caller's responsibility. 3. sysfs_addrm_finish() : release all resources and clean up. Steps 2-a and/or 2-b can be repeated multiple times. Parent's inode is looked up during sysfs_addrm_start(). If available (always at the moment), it's pinned and nlink is updated as sd's are added and removed. Timestamps are updated during finish if any sd has been added or removed. If parent's inode is not available during start, sysfs_mutex ensures that parent inode is not created till add/remove is complete. All the complexity is contained inside the helper functions. Especially, dentry/inode handling is properly hidden from the rest of sysfs which now mostly operate on sysfs_dirents. As an added bonus, codes which use these helpers to add and remove sysfs_dirents are now more structured and simpler. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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