1 files changed, 106 insertions, 317 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index e4f95ba0a3eb..d8574adf0d62 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -38,13 +38,15 @@ struct device_node *of_chosen;
 struct device_node *of_aliases;
 struct device_node *of_stdout;
 
-static struct kset *of_kset;
+struct kset *of_kset;
 
 /*
- * Used to protect the of_aliases; but also overloaded to hold off addition of
- * nodes to sysfs
+ * Used to protect the of_aliases, to hold off addition of nodes to sysfs.
+ * This mutex must be held whenever modifications are being made to the
+ * device tree. The of_{attach,detach}_node() and
+ * of_{add,remove,update}_property() helpers make sure this happens.
  */
-DEFINE_MUTEX(of_aliases_mutex);
+DEFINE_MUTEX(of_mutex);
 
 /* use when traversing tree through the allnext, child, sibling,
  * or parent members of struct device_node.
@@ -90,79 +92,7 @@ int __weak of_node_to_nid(struct device_node *np)
 }
 #endif
 
-#if defined(CONFIG_OF_DYNAMIC)
-/**
- *	of_node_get - Increment refcount of a node
- *	@node:	Node to inc refcount, NULL is supported to
- *		simplify writing of callers
- *
- *	Returns node.
- */
-struct device_node *of_node_get(struct device_node *node)
-{
-	if (node)
-		kobject_get(&node->kobj);
-	return node;
-}
-EXPORT_SYMBOL(of_node_get);
-
-static inline struct device_node *kobj_to_device_node(struct kobject *kobj)
-{
-	return container_of(kobj, struct device_node, kobj);
-}
-
-/**
- *	of_node_release - release a dynamically allocated node
- *	@kref:  kref element of the node to be released
- *
- *	In of_node_put() this function is passed to kref_put()
- *	as the destructor.
- */
-static void of_node_release(struct kobject *kobj)
-{
-	struct device_node *node = kobj_to_device_node(kobj);
-	struct property *prop = node->properties;
-
-	/* We should never be releasing nodes that haven't been detached. */
-	if (!of_node_check_flag(node, OF_DETACHED)) {
-		pr_err("ERROR: Bad of_node_put() on %s\n", node->full_name);
-		dump_stack();
-		return;
-	}
-
-	if (!of_node_check_flag(node, OF_DYNAMIC))
-		return;
-
-	while (prop) {
-		struct property *next = prop->next;
-		kfree(prop->name);
-		kfree(prop->value);
-		kfree(prop);
-		prop = next;
-
-		if (!prop) {
-			prop = node->deadprops;
-			node->deadprops = NULL;
-		}
-	}
-	kfree(node->full_name);
-	kfree(node->data);
-	kfree(node);
-}
-
-/**
- *	of_node_put - Decrement refcount of a node
- *	@node:	Node to dec refcount, NULL is supported to
- *		simplify writing of callers
- *
- */
-void of_node_put(struct device_node *node)
-{
-	if (node)
-		kobject_put(&node->kobj);
-}
-EXPORT_SYMBOL(of_node_put);
-#else
+#ifndef CONFIG_OF_DYNAMIC
 static void of_node_release(struct kobject *kobj)
 {
 	/* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
@@ -201,13 +131,16 @@ static const char *safe_name(struct kobject *kobj, const char *orig_name)
 	return name;
 }
 
-static int __of_add_property_sysfs(struct device_node *np, struct property *pp)
+int __of_add_property_sysfs(struct device_node *np, struct property *pp)
 {
 	int rc;
 
 	/* Important: Don't leak passwords */
 	bool secure = strncmp(pp->name, "security-", 9) == 0;
 
+	if (!of_kset || !of_node_is_attached(np))
+		return 0;
+
 	sysfs_bin_attr_init(&pp->attr);
 	pp->attr.attr.name = safe_name(&np->kobj, pp->name);
 	pp->attr.attr.mode = secure ? S_IRUSR : S_IRUGO;
@@ -219,12 +152,15 @@ static int __of_add_property_sysfs(struct device_node *np, struct property *pp)
 	return rc;
 }
 
-static int __of_node_add(struct device_node *np)
+int __of_attach_node_sysfs(struct device_node *np)
 {
 	const char *name;
 	struct property *pp;
 	int rc;
 
+	if (!of_kset)
+		return 0;
+
 	np->kobj.kset = of_kset;
 	if (!np->parent) {
 		/* Nodes without parents are new top level trees */
@@ -246,59 +182,20 @@ static int __of_node_add(struct device_node *np)
 	return 0;
 }
 
-int of_node_add(struct device_node *np)
-{
-	int rc = 0;
-
-	BUG_ON(!of_node_is_initialized(np));
-
-	/*
-	 * Grab the mutex here so that in a race condition between of_init() and
-	 * of_node_add(), node addition will still be consistent.
-	 */
-	mutex_lock(&of_aliases_mutex);
-	if (of_kset)
-		rc = __of_node_add(np);
-	else
-		/* This scenario may be perfectly valid, but report it anyway */
-		pr_info("of_node_add(%s) before of_init()\n", np->full_name);
-	mutex_unlock(&of_aliases_mutex);
-	return rc;
-}
-
-#if defined(CONFIG_OF_DYNAMIC)
-static void of_node_remove(struct device_node *np)
-{
-	struct property *pp;
-
-	BUG_ON(!of_node_is_initialized(np));
-
-	/* only remove properties if on sysfs */
-	if (of_node_is_attached(np)) {
-		for_each_property_of_node(np, pp)
-			sysfs_remove_bin_file(&np->kobj, &pp->attr);
-		kobject_del(&np->kobj);
-	}
-
-	/* finally remove the kobj_init ref */
-	of_node_put(np);
-}
-#endif
-
 static int __init of_init(void)
 {
 	struct device_node *np;
 
 	/* Create the kset, and register existing nodes */
-	mutex_lock(&of_aliases_mutex);
+	mutex_lock(&of_mutex);
 	of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj);
 	if (!of_kset) {
-		mutex_unlock(&of_aliases_mutex);
+		mutex_unlock(&of_mutex);
 		return -ENOMEM;
 	}
 	for_each_of_allnodes(np)
-		__of_node_add(np);
-	mutex_unlock(&of_aliases_mutex);
+		__of_attach_node_sysfs(np);
+	mutex_unlock(&of_mutex);
 
 	/* Symlink in /proc as required by userspace ABI */
 	if (of_allnodes)
@@ -370,8 +267,8 @@ EXPORT_SYMBOL(of_find_all_nodes);
  * Find a property with a given name for a given node
  * and return the value.
  */
-static const void *__of_get_property(const struct device_node *np,
-				     const char *name, int *lenp)
+const void *__of_get_property(const struct device_node *np,
+			      const char *name, int *lenp)
 {
 	struct property *pp = __of_find_property(np, name, lenp);
 
@@ -1749,32 +1646,10 @@ int of_count_phandle_with_args(const struct device_node *np, const char *list_na
 }
 EXPORT_SYMBOL(of_count_phandle_with_args);
 
-#if defined(CONFIG_OF_DYNAMIC)
-static int of_property_notify(int action, struct device_node *np,
-			      struct property *prop)
-{
-	struct of_prop_reconfig pr;
-
-	/* only call notifiers if the node is attached */
-	if (!of_node_is_attached(np))
-		return 0;
-
-	pr.dn = np;
-	pr.prop = prop;
-	return of_reconfig_notify(action, &pr);
-}
-#else
-static int of_property_notify(int action, struct device_node *np,
-			      struct property *prop)
-{
-	return 0;
-}
-#endif
-
 /**
  * __of_add_property - Add a property to a node without lock operations
  */
-static int __of_add_property(struct device_node *np, struct property *prop)
+int __of_add_property(struct device_node *np, struct property *prop)
 {
 	struct property **next;
 
@@ -1800,22 +1675,49 @@ int of_add_property(struct device_node *np, struct property *prop)
 	unsigned long flags;
 	int rc;
 
-	rc = of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop);
-	if (rc)
-		return rc;
+	mutex_lock(&of_mutex);
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
 	rc = __of_add_property(np, prop);
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
-	if (rc)
-		return rc;
 
-	if (of_node_is_attached(np))
+	if (!rc)
 		__of_add_property_sysfs(np, prop);
 
+	mutex_unlock(&of_mutex);
+
+	if (!rc)
+		of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL);
+
 	return rc;
 }
 
+int __of_remove_property(struct device_node *np, struct property *prop)
+{
+	struct property **next;
+
+	for (next = &np->properties; *next; next = &(*next)->next) {
+		if (*next == prop)
+			break;
+	}
+	if (*next == NULL)
+		return -ENODEV;
+
+	/* found the node */
+	*next = prop->next;
+	prop->next = np->deadprops;
+	np->deadprops = prop;
+
+	return 0;
+}
+
+void __of_remove_property_sysfs(struct device_node *np, struct property *prop)
+{
+	/* at early boot, bail here and defer setup to of_init() */
+	if (of_kset && of_node_is_attached(np))
+		sysfs_remove_bin_file(&np->kobj, &prop->attr);
+}
+
 /**
  * of_remove_property - Remove a property from a node.
  *
@@ -1826,211 +1728,98 @@ int of_add_property(struct device_node *np, struct property *prop)
  */
 int of_remove_property(struct device_node *np, struct property *prop)
 {
-	struct property **next;
 	unsigned long flags;
-	int found = 0;
 	int rc;
 
-	rc = of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop);
-	if (rc)
-		return rc;
+	mutex_lock(&of_mutex);
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
-	next = &np->properties;
-	while (*next) {
-		if (*next == prop) {
-			/* found the node */
-			*next = prop->next;
-			prop->next = np->deadprops;
-			np->deadprops = prop;
-			found = 1;
-			break;
-		}
-		next = &(*next)->next;
-	}
+	rc = __of_remove_property(np, prop);
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
-	if (!found)
-		return -ENODEV;
+	if (!rc)
+		__of_remove_property_sysfs(np, prop);
 
-	/* at early boot, bail hear and defer setup to of_init() */
-	if (!of_kset)
-		return 0;
+	mutex_unlock(&of_mutex);
 
-	sysfs_remove_bin_file(&np->kobj, &prop->attr);
+	if (!rc)
+		of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL);
 
-	return 0;
+	return rc;
 }
 
-/*
- * of_update_property - Update a property in a node, if the property does
- * not exist, add it.
- *
- * Note that we don't actually remove it, since we have given out
- * who-knows-how-many pointers to the data using get-property.
- * Instead we just move the property to the "dead properties" list,
- * and add the new property to the property list
- */
-int of_update_property(struct device_node *np, struct property *newprop)
+int __of_update_property(struct device_node *np, struct property *newprop,
+		struct property **oldpropp)
 {
 	struct property **next, *oldprop;
-	unsigned long flags;
-	int rc;
-
-	rc = of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop);
-	if (rc)
-		return rc;
 
-	if (!newprop->name)
-		return -EINVAL;
+	for (next = &np->properties; *next; next = &(*next)->next) {
+		if (of_prop_cmp((*next)->name, newprop->name) == 0)
+			break;
+	}
+	*oldpropp = oldprop = *next;
 
-	raw_spin_lock_irqsave(&devtree_lock, flags);
-	next = &np->properties;
-	oldprop = __of_find_property(np, newprop->name, NULL);
-	if (!oldprop) {
-		/* add the new node */
-		rc = __of_add_property(np, newprop);
-	} else while (*next) {
+	if (oldprop) {
 		/* replace the node */
-		if (*next == oldprop) {
-			newprop->next = oldprop->next;
-			*next = newprop;
-			oldprop->next = np->deadprops;
-			np->deadprops = oldprop;
-			break;
-		}
-		next = &(*next)->next;
+		newprop->next = oldprop->next;
+		*next = newprop;
+		oldprop->next = np->deadprops;
+		np->deadprops = oldprop;
+	} else {
+		/* new node */
+		newprop->next = NULL;
+		*next = newprop;
 	}
-	raw_spin_unlock_irqrestore(&devtree_lock, flags);
-	if (rc)
-		return rc;
 
+	return 0;
+}
+
+void __of_update_property_sysfs(struct device_node *np, struct property *newprop,
+		struct property *oldprop)
+{
 	/* At early boot, bail out and defer setup to of_init() */
 	if (!of_kset)
-		return 0;
+		return;
 
-	/* Update the sysfs attribute */
 	if (oldprop)
 		sysfs_remove_bin_file(&np->kobj, &oldprop->attr);
 	__of_add_property_sysfs(np, newprop);
-
-	return 0;
 }
 
-#if defined(CONFIG_OF_DYNAMIC)
 /*
- * Support for dynamic device trees.
+ * of_update_property - Update a property in a node, if the property does
+ * not exist, add it.
  *
- * On some platforms, the device tree can be manipulated at runtime.
- * The routines in this section support adding, removing and changing
- * device tree nodes.
- */
-
-static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain);
-
-int of_reconfig_notifier_register(struct notifier_block *nb)
-{
-	return blocking_notifier_chain_register(&of_reconfig_chain, nb);
-}
-EXPORT_SYMBOL_GPL(of_reconfig_notifier_register);
-
-int of_reconfig_notifier_unregister(struct notifier_block *nb)
-{
-	return blocking_notifier_chain_unregister(&of_reconfig_chain, nb);
-}
-EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister);
-
-int of_reconfig_notify(unsigned long action, void *p)
-{
-	int rc;
-
-	rc = blocking_notifier_call_chain(&of_reconfig_chain, action, p);
-	return notifier_to_errno(rc);
-}
-
-/**
- * of_attach_node - Plug a device node into the tree and global list.
+ * Note that we don't actually remove it, since we have given out
+ * who-knows-how-many pointers to the data using get-property.
+ * Instead we just move the property to the "dead properties" list,
+ * and add the new property to the property list
  */
-int of_attach_node(struct device_node *np)
+int of_update_property(struct device_node *np, struct property *newprop)
 {
+	struct property *oldprop;
 	unsigned long flags;
 	int rc;
 
-	rc = of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, np);
-	if (rc)
-		return rc;
-
-	raw_spin_lock_irqsave(&devtree_lock, flags);
-	np->sibling = np->parent->child;
-	np->allnext = np->parent->allnext;
-	np->parent->allnext = np;
-	np->parent->child = np;
-	of_node_clear_flag(np, OF_DETACHED);
-	raw_spin_unlock_irqrestore(&devtree_lock, flags);
-
-	of_node_add(np);
-	return 0;
-}
-
-/**
- * of_detach_node - "Unplug" a node from the device tree.
- *
- * The caller must hold a reference to the node.  The memory associated with
- * the node is not freed until its refcount goes to zero.
- */
-int of_detach_node(struct device_node *np)
-{
-	struct device_node *parent;
-	unsigned long flags;
-	int rc = 0;
+	if (!newprop->name)
+		return -EINVAL;
 
-	rc = of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np);
-	if (rc)
-		return rc;
+	mutex_lock(&of_mutex);
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
+	rc = __of_update_property(np, newprop, &oldprop);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
-	if (of_node_check_flag(np, OF_DETACHED)) {
-		/* someone already detached it */
-		raw_spin_unlock_irqrestore(&devtree_lock, flags);
-		return rc;
-	}
-
-	parent = np->parent;
-	if (!parent) {
-		raw_spin_unlock_irqrestore(&devtree_lock, flags);
-		return rc;
-	}
-
-	if (of_allnodes == np)
-		of_allnodes = np->allnext;
-	else {
-		struct device_node *prev;
-		for (prev = of_allnodes;
-		     prev->allnext != np;
-		     prev = prev->allnext)
-			;
-		prev->allnext = np->allnext;
-	}
+	if (!rc)
+		__of_update_property_sysfs(np, newprop, oldprop);
 
-	if (parent->child == np)
-		parent->child = np->sibling;
-	else {
-		struct device_node *prevsib;
-		for (prevsib = np->parent->child;
-		     prevsib->sibling != np;
-		     prevsib = prevsib->sibling)
-			;
-		prevsib->sibling = np->sibling;
-	}
+	mutex_unlock(&of_mutex);
 
-	of_node_set_flag(np, OF_DETACHED);
-	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+	if (!rc)
+		of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop, oldprop);
 
-	of_node_remove(np);
 	return rc;
 }
-#endif /* defined(CONFIG_OF_DYNAMIC) */
 
 static void of_alias_add(struct alias_prop *ap, struct device_node *np,
 			 int id, const char *stem, int stem_len)
@@ -2126,7 +1915,7 @@ int of_alias_get_id(struct device_node *np, const char *stem)
 	struct alias_prop *app;
 	int id = -ENODEV;
 
-	mutex_lock(&of_aliases_mutex);
+	mutex_lock(&of_mutex);
 	list_for_each_entry(app, &aliases_lookup, link) {
 		if (strcmp(app->stem, stem) != 0)
 			continue;
@@ -2136,7 +1925,7 @@ int of_alias_get_id(struct device_node *np, const char *stem)
 			break;
 		}
 	}
-	mutex_unlock(&of_aliases_mutex);
+	mutex_unlock(&of_mutex);
 
 	return id;
 }