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-rw-r--r--drivers/of/base.c423
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;
}