summaryrefslogtreecommitdiffstats
path: root/lib/kobject.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2013-11-07 02:03:42 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2013-11-07 03:42:15 +0100
commit0324e74534241f3f00910ec04ef67de1fe1542f4 (patch)
tree88f0b2a40a47dc0a22c0ce5e9b75a58470a56204 /lib/kobject.c
parentMerge tag 'char-misc-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/g... (diff)
parentsysfs: rename sysfs_assoc_lock and explain what it's about (diff)
downloadlinux-0324e74534241f3f00910ec04ef67de1fe1542f4.tar.xz
linux-0324e74534241f3f00910ec04ef67de1fe1542f4.zip
Merge tag 'driver-core-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core / sysfs patches from Greg KH: "Here's the big driver core / sysfs update for 3.13-rc1. There's lots of dev_groups updates for different subsystems, as they all get slowly migrated over to the safe versions of the attribute groups (removing userspace races with the creation of the sysfs files.) Also in here are some kobject updates, devres expansions, and the first round of Tejun's sysfs reworking to enable it to be used by other subsystems as a backend for an in-kernel filesystem. All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (83 commits) sysfs: rename sysfs_assoc_lock and explain what it's about sysfs: use generic_file_llseek() for sysfs_file_operations sysfs: return correct error code on unimplemented mmap() mdio_bus: convert bus code to use dev_groups device: Make dev_WARN/dev_WARN_ONCE print device as well as driver name sysfs: separate out dup filename warning into a separate function sysfs: move sysfs_hash_and_remove() to fs/sysfs/dir.c sysfs: remove unused sysfs_get_dentry() prototype sysfs: honor bin_attr.attr.ignore_lockdep sysfs: merge sysfs_elem_bin_attr into sysfs_elem_attr devres: restore zeroing behavior of devres_alloc() sysfs: fix sysfs_write_file for bin file input: gameport: convert bus code to use dev_groups input: serio: remove bus usage of dev_attrs input: serio: use DEVICE_ATTR_RO() i2o: convert bus code to use dev_groups memstick: convert bus code to use dev_groups tifm: convert bus code to use dev_groups virtio: convert bus code to use dev_groups ipack: convert bus code to use dev_groups ...
Diffstat (limited to 'lib/kobject.c')
-rw-r--r--lib/kobject.c93
1 files changed, 89 insertions, 4 deletions
diff --git a/lib/kobject.c b/lib/kobject.c
index 084f7b18d0c0..7a1c203083eb 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -13,11 +13,33 @@
*/
#include <linux/kobject.h>
+#include <linux/kobj_completion.h>
#include <linux/string.h>
#include <linux/export.h>
#include <linux/stat.h>
#include <linux/slab.h>
+/**
+ * kobject_namespace - return @kobj's namespace tag
+ * @kobj: kobject in question
+ *
+ * Returns namespace tag of @kobj if its parent has namespace ops enabled
+ * and thus @kobj should have a namespace tag associated with it. Returns
+ * %NULL otherwise.
+ */
+const void *kobject_namespace(struct kobject *kobj)
+{
+ const struct kobj_ns_type_operations *ns_ops = kobj_ns_ops(kobj);
+ const void *ns;
+
+ if (!ns_ops || ns_ops->type == KOBJ_NS_TYPE_NONE)
+ return NULL;
+
+ ns = kobj->ktype->namespace(kobj);
+ WARN_ON(!ns); /* @kobj in a namespace is required to have !NULL tag */
+ return ns;
+}
+
/*
* populate_dir - populate directory with attributes.
* @kobj: object we're working on.
@@ -46,13 +68,21 @@ static int populate_dir(struct kobject *kobj)
static int create_dir(struct kobject *kobj)
{
- int error = 0;
- error = sysfs_create_dir(kobj);
+ int error;
+
+ error = sysfs_create_dir_ns(kobj, kobject_namespace(kobj));
if (!error) {
error = populate_dir(kobj);
if (error)
sysfs_remove_dir(kobj);
}
+
+ /*
+ * @kobj->sd may be deleted by an ancestor going away. Hold an
+ * extra reference so that it stays until @kobj is gone.
+ */
+ sysfs_get(kobj->sd);
+
return error;
}
@@ -428,7 +458,7 @@ int kobject_rename(struct kobject *kobj, const char *new_name)
goto out;
}
- error = sysfs_rename_dir(kobj, new_name);
+ error = sysfs_rename_dir_ns(kobj, new_name, kobject_namespace(kobj));
if (error)
goto out;
@@ -472,6 +502,7 @@ int kobject_move(struct kobject *kobj, struct kobject *new_parent)
if (kobj->kset)
new_parent = kobject_get(&kobj->kset->kobj);
}
+
/* old object path */
devpath = kobject_get_path(kobj, GFP_KERNEL);
if (!devpath) {
@@ -486,7 +517,7 @@ int kobject_move(struct kobject *kobj, struct kobject *new_parent)
sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
envp[0] = devpath_string;
envp[1] = NULL;
- error = sysfs_move_dir(kobj, new_parent);
+ error = sysfs_move_dir_ns(kobj, new_parent, kobject_namespace(kobj));
if (error)
goto out;
old_parent = kobj->parent;
@@ -508,10 +539,15 @@ out:
*/
void kobject_del(struct kobject *kobj)
{
+ struct sysfs_dirent *sd;
+
if (!kobj)
return;
+ sd = kobj->sd;
sysfs_remove_dir(kobj);
+ sysfs_put(sd);
+
kobj->state_in_sysfs = 0;
kobj_kset_leave(kobj);
kobject_put(kobj->parent);
@@ -727,6 +763,55 @@ const struct sysfs_ops kobj_sysfs_ops = {
};
/**
+ * kobj_completion_init - initialize a kobj_completion object.
+ * @kc: kobj_completion
+ * @ktype: type of kobject to initialize
+ *
+ * kobj_completion structures can be embedded within structures with different
+ * lifetime rules. During the release of the enclosing object, we can
+ * wait on the release of the kobject so that we don't free it while it's
+ * still busy.
+ */
+void kobj_completion_init(struct kobj_completion *kc, struct kobj_type *ktype)
+{
+ init_completion(&kc->kc_unregister);
+ kobject_init(&kc->kc_kobj, ktype);
+}
+EXPORT_SYMBOL_GPL(kobj_completion_init);
+
+/**
+ * kobj_completion_release - release a kobj_completion object
+ * @kobj: kobject embedded in kobj_completion
+ *
+ * Used with kobject_release to notify waiters that the kobject has been
+ * released.
+ */
+void kobj_completion_release(struct kobject *kobj)
+{
+ struct kobj_completion *kc = kobj_to_kobj_completion(kobj);
+ complete(&kc->kc_unregister);
+}
+EXPORT_SYMBOL_GPL(kobj_completion_release);
+
+/**
+ * kobj_completion_del_and_wait - release the kobject and wait for it
+ * @kc: kobj_completion object to release
+ *
+ * Delete the kobject from sysfs and drop the reference count. Then wait
+ * until any other outstanding references are also dropped. This routine
+ * is only necessary once other references may have been taken on the
+ * kobject. Typically this happens when the kobject has been published
+ * to sysfs via kobject_add.
+ */
+void kobj_completion_del_and_wait(struct kobj_completion *kc)
+{
+ kobject_del(&kc->kc_kobj);
+ kobject_put(&kc->kc_kobj);
+ wait_for_completion(&kc->kc_unregister);
+}
+EXPORT_SYMBOL_GPL(kobj_completion_del_and_wait);
+
+/**
* kset_register - initialize and add a kset.
* @k: kset.
*/