aboutsummaryrefslogtreecommitdiff
path: root/lib/kobject.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/kobject.c')
-rw-r--r--lib/kobject.c361
1 files changed, 282 insertions, 79 deletions
diff --git a/lib/kobject.c b/lib/kobject.c
index 0d03252f87a..58751bb80a7 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -14,9 +14,28 @@
#include <linux/kobject.h>
#include <linux/string.h>
-#include <linux/module.h>
+#include <linux/export.h>
#include <linux/stat.h>
#include <linux/slab.h>
+#include <linux/random.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);
+
+ if (!ns_ops || ns_ops->type == KOBJ_NS_TYPE_NONE)
+ return NULL;
+
+ return kobj->ktype->namespace(kobj);
+}
/*
* populate_dir - populate directory with attributes.
@@ -46,21 +65,39 @@ static int populate_dir(struct kobject *kobj)
static int create_dir(struct kobject *kobj)
{
- int error = 0;
- if (kobject_name(kobj)) {
- error = sysfs_create_dir(kobj);
- if (!error) {
- error = populate_dir(kobj);
- if (error)
- sysfs_remove_dir(kobj);
- }
+ const struct kobj_ns_type_operations *ops;
+ int error;
+
+ error = sysfs_create_dir_ns(kobj, kobject_namespace(kobj));
+ if (error)
+ return error;
+
+ error = populate_dir(kobj);
+ if (error) {
+ sysfs_remove_dir(kobj);
+ return error;
}
- return error;
-}
-static inline struct kobject *to_kobj(struct list_head *entry)
-{
- return container_of(entry, struct kobject, entry);
+ /*
+ * @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);
+
+ /*
+ * If @kobj has ns_ops, its children need to be filtered based on
+ * their namespace tags. Enable namespace support on @kobj->sd.
+ */
+ ops = kobj_child_ns_ops(kobj);
+ if (ops) {
+ BUG_ON(ops->type <= KOBJ_NS_TYPE_NONE);
+ BUG_ON(ops->type >= KOBJ_NS_TYPES);
+ BUG_ON(!kobj_ns_type_registered(ops->type));
+
+ sysfs_enable_ns(kobj->sd);
+ }
+
+ return 0;
}
static int get_kobj_path_length(struct kobject *kobj)
@@ -95,7 +132,7 @@ static void fill_kobj_path(struct kobject *kobj, char *path, int length)
}
pr_debug("kobject: '%s' (%p): %s: path = '%s'\n", kobject_name(kobj),
- kobj, __FUNCTION__, path);
+ kobj, __func__, path);
}
/**
@@ -169,9 +206,8 @@ static int kobject_add_internal(struct kobject *kobj)
return -ENOENT;
if (!kobj->name || !kobj->name[0]) {
- pr_debug("kobject: (%p): attempted to be registered with empty "
+ WARN(1, "kobject: (%p): attempted to be registered with empty "
"name!\n", kobj);
- WARN_ON(1);
return -EINVAL;
}
@@ -186,7 +222,7 @@ static int kobject_add_internal(struct kobject *kobj)
}
pr_debug("kobject: '%s' (%p): %s: parent: '%s', set: '%s'\n",
- kobject_name(kobj), kobj, __FUNCTION__,
+ kobject_name(kobj), kobj, __func__,
parent ? kobject_name(parent) : "<NULL>",
kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>");
@@ -198,14 +234,14 @@ static int kobject_add_internal(struct kobject *kobj)
/* be noisy on error issues */
if (error == -EEXIST)
- printk(KERN_ERR "%s failed for %s with "
- "-EEXIST, don't try to register things with "
- "the same name in the same directory.\n",
- __FUNCTION__, kobject_name(kobj));
+ WARN(1, "%s failed for %s with "
+ "-EEXIST, don't try to register things with "
+ "the same name in the same directory.\n",
+ __func__, kobject_name(kobj));
else
- printk(KERN_ERR "%s failed for %s (%d)\n",
- __FUNCTION__, kobject_name(kobj), error);
- dump_stack();
+ WARN(1, "%s failed for %s (error: %d parent: %s)\n",
+ __func__, kobject_name(kobj), error,
+ parent ? kobject_name(parent) : "'none'");
} else
kobj->state_in_sysfs = 1;
@@ -218,25 +254,26 @@ static int kobject_add_internal(struct kobject *kobj)
* @fmt: format string used to build the name
* @vargs: vargs to format the string.
*/
-static int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
+int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
va_list vargs)
{
- va_list aq;
- char *name;
+ const char *old_name = kobj->name;
+ char *s;
- va_copy(aq, vargs);
- name = kvasprintf(GFP_KERNEL, fmt, vargs);
- va_end(aq);
+ if (kobj->name && !fmt)
+ return 0;
- if (!name)
+ kobj->name = kvasprintf(GFP_KERNEL, fmt, vargs);
+ if (!kobj->name) {
+ kobj->name = old_name;
return -ENOMEM;
+ }
- /* Free the old name, if necessary. */
- kfree(kobj->name);
-
- /* Now, set the new name */
- kobj->name = name;
+ /* ewww... some of these buggers have '/' in the name ... */
+ while ((s = strchr(kobj->name, '/')))
+ s[0] = '!';
+ kfree(old_name);
return 0;
}
@@ -251,12 +288,12 @@ static int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
*/
int kobject_set_name(struct kobject *kobj, const char *fmt, ...)
{
- va_list args;
+ va_list vargs;
int retval;
- va_start(args, fmt);
- retval = kobject_set_name_vargs(kobj, fmt, args);
- va_end(args);
+ va_start(vargs, fmt);
+ retval = kobject_set_name_vargs(kobj, fmt, vargs);
+ va_end(vargs);
return retval;
}
@@ -306,12 +343,9 @@ EXPORT_SYMBOL(kobject_init);
static int kobject_add_varg(struct kobject *kobj, struct kobject *parent,
const char *fmt, va_list vargs)
{
- va_list aq;
int retval;
- va_copy(aq, vargs);
- retval = kobject_set_name_vargs(kobj, fmt, aq);
- va_end(aq);
+ retval = kobject_set_name_vargs(kobj, fmt, vargs);
if (retval) {
printk(KERN_ERR "kobject: can not set name properly!\n");
return retval;
@@ -331,7 +365,7 @@ static int kobject_add_varg(struct kobject *kobj, struct kobject *parent,
*
* If @parent is set, then the parent of the @kobj will be set to it.
* If @parent is NULL, then the parent of the @kobj will be set to the
- * kobject associted with the kset assigned to this kobject. If no kset
+ * kobject associated with the kset assigned to this kobject. If no kset
* is assigned to the kobject, then the kobject will be located in the
* root of the sysfs tree.
*
@@ -400,11 +434,17 @@ EXPORT_SYMBOL_GPL(kobject_init_and_add);
* kobject_rename - change the name of an object
* @kobj: object in question.
* @new_name: object's new name
+ *
+ * It is the responsibility of the caller to provide mutual
+ * exclusion between two different calls of kobject_rename
+ * on the same kobject and to ensure that new_name is valid and
+ * won't conflict with other kobjects.
*/
int kobject_rename(struct kobject *kobj, const char *new_name)
{
int error = 0;
const char *devpath = NULL;
+ const char *dup_name = NULL, *name;
char *devpath_string = NULL;
char *envp[2];
@@ -414,19 +454,6 @@ int kobject_rename(struct kobject *kobj, const char *new_name)
if (!kobj->parent)
return -EINVAL;
- /* see if this name is already in use */
- if (kobj->kset) {
- struct kobject *temp_kobj;
- temp_kobj = kset_find_obj(kobj->kset, new_name);
- if (temp_kobj) {
- printk(KERN_WARNING "kobject '%s' cannot be renamed "
- "to '%s' as '%s' is already in existence.\n",
- kobject_name(kobj), new_name, new_name);
- kobject_put(temp_kobj);
- return -EINVAL;
- }
- }
-
devpath = kobject_get_path(kobj, GFP_KERNEL);
if (!devpath) {
error = -ENOMEM;
@@ -441,21 +468,34 @@ int kobject_rename(struct kobject *kobj, const char *new_name)
envp[0] = devpath_string;
envp[1] = NULL;
- error = sysfs_rename_dir(kobj, new_name);
+ name = dup_name = kstrdup(new_name, GFP_KERNEL);
+ if (!name) {
+ error = -ENOMEM;
+ goto out;
+ }
+
+ error = sysfs_rename_dir_ns(kobj, new_name, kobject_namespace(kobj));
+ if (error)
+ goto out;
+
+ /* Install the new kobject name */
+ dup_name = kobj->name;
+ kobj->name = name;
/* This function is mostly/only used for network interface.
* Some hotplug package track interfaces by their name and
* therefore want to know when the name is changed by the user. */
- if (!error)
- kobject_uevent_env(kobj, KOBJ_MOVE, envp);
+ kobject_uevent_env(kobj, KOBJ_MOVE, envp);
out:
+ kfree(dup_name);
kfree(devpath_string);
kfree(devpath);
kobject_put(kobj);
return error;
}
+EXPORT_SYMBOL_GPL(kobject_rename);
/**
* kobject_move - move object to another parent
@@ -478,6 +518,7 @@ 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) {
@@ -492,7 +533,7 @@ 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;
@@ -514,10 +555,15 @@ out:
*/
void kobject_del(struct kobject *kobj)
{
+ struct kernfs_node *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);
@@ -535,6 +581,13 @@ struct kobject *kobject_get(struct kobject *kobj)
return kobj;
}
+static struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj)
+{
+ if (!kref_get_unless_zero(&kobj->kref))
+ kobj = NULL;
+ return kobj;
+}
+
/*
* kobject_cleanup - free kobject resources.
* @kobj: object to cleanup
@@ -544,8 +597,8 @@ static void kobject_cleanup(struct kobject *kobj)
struct kobj_type *t = get_ktype(kobj);
const char *name = kobj->name;
- pr_debug("kobject: '%s' (%p): %s\n",
- kobject_name(kobj), kobj, __FUNCTION__);
+ pr_debug("kobject: '%s' (%p): %s, parent %p\n",
+ kobject_name(kobj), kobj, __func__, kobj->parent);
if (t && !t->release)
pr_debug("kobject: '%s' (%p): does not have a release() "
@@ -579,9 +632,27 @@ static void kobject_cleanup(struct kobject *kobj)
}
}
+#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
+static void kobject_delayed_cleanup(struct work_struct *work)
+{
+ kobject_cleanup(container_of(to_delayed_work(work),
+ struct kobject, release));
+}
+#endif
+
static void kobject_release(struct kref *kref)
{
- kobject_cleanup(container_of(kref, struct kobject, kref));
+ struct kobject *kobj = container_of(kref, struct kobject, kref);
+#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
+ unsigned long delay = HZ + HZ * (get_random_int() & 0x3);
+ pr_info("kobject: '%s' (%p): %s, parent %p (delayed %ld)\n",
+ kobject_name(kobj), kobj, __func__, kobj->parent, delay);
+ INIT_DELAYED_WORK(&kobj->release, kobject_delayed_cleanup);
+
+ schedule_delayed_work(&kobj->release, delay);
+#else
+ kobject_cleanup(kobj);
+#endif
}
/**
@@ -592,13 +663,18 @@ static void kobject_release(struct kref *kref)
*/
void kobject_put(struct kobject *kobj)
{
- if (kobj)
+ if (kobj) {
+ if (!kobj->state_initialized)
+ WARN(1, KERN_WARNING "kobject: '%s' (%p): is not "
+ "initialized, yet kobject_put() is being "
+ "called.\n", kobject_name(kobj), kobj);
kref_put(&kobj->kref, kobject_release);
+ }
}
static void dynamic_kobj_release(struct kobject *kobj)
{
- pr_debug("kobject: (%p): %s\n", kobj, __FUNCTION__);
+ pr_debug("kobject: (%p): %s\n", kobj, __func__);
kfree(kobj);
}
@@ -633,7 +709,7 @@ struct kobject *kobject_create(void)
/**
* kobject_create_and_add - create a struct kobject dynamically and register it with sysfs
*
- * @name: the name for the kset
+ * @name: the name for the kobject
* @parent: the parent kobject of this kobject, if any.
*
* This function creates a kobject structure dynamically and registers it
@@ -655,7 +731,7 @@ struct kobject *kobject_create_and_add(const char *name, struct kobject *parent)
retval = kobject_add(kobj, parent, "%s", name);
if (retval) {
printk(KERN_WARNING "%s: kobject_add error: %d\n",
- __FUNCTION__, retval);
+ __func__, retval);
kobject_put(kobj);
kobj = NULL;
}
@@ -699,10 +775,11 @@ static ssize_t kobj_attr_store(struct kobject *kobj, struct attribute *attr,
return ret;
}
-struct sysfs_ops kobj_sysfs_ops = {
+const struct sysfs_ops kobj_sysfs_ops = {
.show = kobj_attr_show,
.store = kobj_attr_store,
};
+EXPORT_SYMBOL_GPL(kobj_sysfs_ops);
/**
* kset_register - initialize and add a kset.
@@ -731,6 +808,7 @@ void kset_unregister(struct kset *k)
{
if (!k)
return;
+ kobject_del(&k->kobj);
kobject_put(&k->kobj);
}
@@ -745,17 +823,18 @@ void kset_unregister(struct kset *k)
*/
struct kobject *kset_find_obj(struct kset *kset, const char *name)
{
- struct list_head *entry;
+ struct kobject *k;
struct kobject *ret = NULL;
spin_lock(&kset->list_lock);
- list_for_each(entry, &kset->list) {
- struct kobject *k = to_kobj(entry);
+
+ list_for_each_entry(k, &kset->list, entry) {
if (kobject_name(k) && !strcmp(kobject_name(k), name)) {
- ret = kobject_get(k);
+ ret = kobject_get_unless_zero(k);
break;
}
}
+
spin_unlock(&kset->list_lock);
return ret;
}
@@ -764,7 +843,7 @@ static void kset_release(struct kobject *kobj)
{
struct kset *kset = container_of(kobj, struct kset, kobj);
pr_debug("kobject: '%s' (%p): %s\n",
- kobject_name(kobj), kobj, __FUNCTION__);
+ kobject_name(kobj), kobj, __func__);
kfree(kset);
}
@@ -789,15 +868,20 @@ static struct kobj_type kset_ktype = {
* If the kset was not able to be created, NULL will be returned.
*/
static struct kset *kset_create(const char *name,
- struct kset_uevent_ops *uevent_ops,
+ const struct kset_uevent_ops *uevent_ops,
struct kobject *parent_kobj)
{
struct kset *kset;
+ int retval;
kset = kzalloc(sizeof(*kset), GFP_KERNEL);
if (!kset)
return NULL;
- kobject_set_name(&kset->kobj, name);
+ retval = kobject_set_name(&kset->kobj, "%s", name);
+ if (retval) {
+ kfree(kset);
+ return NULL;
+ }
kset->uevent_ops = uevent_ops;
kset->kobj.parent = parent_kobj;
@@ -827,7 +911,7 @@ static struct kset *kset_create(const char *name,
* If the kset was not able to be created, NULL will be returned.
*/
struct kset *kset_create_and_add(const char *name,
- struct kset_uevent_ops *uevent_ops,
+ const struct kset_uevent_ops *uevent_ops,
struct kobject *parent_kobj)
{
struct kset *kset;
@@ -845,6 +929,125 @@ struct kset *kset_create_and_add(const char *name,
}
EXPORT_SYMBOL_GPL(kset_create_and_add);
+
+static DEFINE_SPINLOCK(kobj_ns_type_lock);
+static const struct kobj_ns_type_operations *kobj_ns_ops_tbl[KOBJ_NS_TYPES];
+
+int kobj_ns_type_register(const struct kobj_ns_type_operations *ops)
+{
+ enum kobj_ns_type type = ops->type;
+ int error;
+
+ spin_lock(&kobj_ns_type_lock);
+
+ error = -EINVAL;
+ if (type >= KOBJ_NS_TYPES)
+ goto out;
+
+ error = -EINVAL;
+ if (type <= KOBJ_NS_TYPE_NONE)
+ goto out;
+
+ error = -EBUSY;
+ if (kobj_ns_ops_tbl[type])
+ goto out;
+
+ error = 0;
+ kobj_ns_ops_tbl[type] = ops;
+
+out:
+ spin_unlock(&kobj_ns_type_lock);
+ return error;
+}
+
+int kobj_ns_type_registered(enum kobj_ns_type type)
+{
+ int registered = 0;
+
+ spin_lock(&kobj_ns_type_lock);
+ if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES))
+ registered = kobj_ns_ops_tbl[type] != NULL;
+ spin_unlock(&kobj_ns_type_lock);
+
+ return registered;
+}
+
+const struct kobj_ns_type_operations *kobj_child_ns_ops(struct kobject *parent)
+{
+ const struct kobj_ns_type_operations *ops = NULL;
+
+ if (parent && parent->ktype->child_ns_type)
+ ops = parent->ktype->child_ns_type(parent);
+
+ return ops;
+}
+
+const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj)
+{
+ return kobj_child_ns_ops(kobj->parent);
+}
+
+bool kobj_ns_current_may_mount(enum kobj_ns_type type)
+{
+ bool may_mount = true;
+
+ spin_lock(&kobj_ns_type_lock);
+ if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
+ kobj_ns_ops_tbl[type])
+ may_mount = kobj_ns_ops_tbl[type]->current_may_mount();
+ spin_unlock(&kobj_ns_type_lock);
+
+ return may_mount;
+}
+
+void *kobj_ns_grab_current(enum kobj_ns_type type)
+{
+ void *ns = NULL;
+
+ spin_lock(&kobj_ns_type_lock);
+ if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
+ kobj_ns_ops_tbl[type])
+ ns = kobj_ns_ops_tbl[type]->grab_current_ns();
+ spin_unlock(&kobj_ns_type_lock);
+
+ return ns;
+}
+
+const void *kobj_ns_netlink(enum kobj_ns_type type, struct sock *sk)
+{
+ const void *ns = NULL;
+
+ spin_lock(&kobj_ns_type_lock);
+ if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
+ kobj_ns_ops_tbl[type])
+ ns = kobj_ns_ops_tbl[type]->netlink_ns(sk);
+ spin_unlock(&kobj_ns_type_lock);
+
+ return ns;
+}
+
+const void *kobj_ns_initial(enum kobj_ns_type type)
+{
+ const void *ns = NULL;
+
+ spin_lock(&kobj_ns_type_lock);
+ if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
+ kobj_ns_ops_tbl[type])
+ ns = kobj_ns_ops_tbl[type]->initial_ns();
+ spin_unlock(&kobj_ns_type_lock);
+
+ return ns;
+}
+
+void kobj_ns_drop(enum kobj_ns_type type, void *ns)
+{
+ spin_lock(&kobj_ns_type_lock);
+ if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
+ kobj_ns_ops_tbl[type] && kobj_ns_ops_tbl[type]->drop_ns)
+ kobj_ns_ops_tbl[type]->drop_ns(ns);
+ spin_unlock(&kobj_ns_type_lock);
+}
+
EXPORT_SYMBOL(kobject_get);
EXPORT_SYMBOL(kobject_put);
EXPORT_SYMBOL(kobject_del);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-10 09:55:04 +0000