[PATCH 03/10] of: Move CONFIG_OF_DYNAMIC code into a separate file

From: Grant Likely
Date: Wed Jul 23 2014 - 19:46:54 EST


Split the dynamic device tree code into a separate file to make it
really clear what features CONFIF_OF_DYNAMIC add to the kernel. Without
CONFIG_OF_DYNAMIC only properties can be changed, and notifiers do not
get sent. Enabling it turns on reference counting, notifiers and the
ability to add and remove nodes.

v2: Moved of_node_release() into dynamic.c

Signed-off-by: Grant Likely <grant.likely@xxxxxxxxxx>
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
---
drivers/of/Makefile | 1 +
drivers/of/base.c | 230 +-----------------------------------------------
drivers/of/dynamic.c | 216 +++++++++++++++++++++++++++++++++++++++++++++
drivers/of/of_private.h | 18 ++++
4 files changed, 236 insertions(+), 229 deletions(-)
create mode 100644 drivers/of/dynamic.c

diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index 099b1fb00af4..08e6c0f79806 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -1,4 +1,5 @@
obj-y = base.o device.o platform.o
+obj-$(CONFIG_OF_DYNAMIC) += dynamic.o
obj-$(CONFIG_OF_FLATTREE) += fdt.o
obj-$(CONFIG_OF_EARLY_FLATTREE) += fdt_address.o
obj-$(CONFIG_OF_PROMTREE) += pdt.o
diff --git a/drivers/of/base.c b/drivers/of/base.c
index e48a1b90a392..0d8955605738 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -88,79 +88,7 @@ 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 */
@@ -264,25 +192,6 @@ int of_node_add(struct device_node *np)
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;
@@ -1747,28 +1656,6 @@ 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
*/
@@ -1915,121 +1802,6 @@ int of_update_property(struct device_node *np, struct property *newprop)
return 0;
}

-#if defined(CONFIG_OF_DYNAMIC)
-/*
- * Support for dynamic device trees.
- *
- * 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.
- */
-int of_attach_node(struct device_node *np)
-{
- 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;
-
- rc = of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np);
- if (rc)
- return rc;
-
- raw_spin_lock_irqsave(&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 (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;
- }
-
- of_node_set_flag(np, OF_DETACHED);
- raw_spin_unlock_irqrestore(&devtree_lock, flags);
-
- 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)
{
diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
new file mode 100644
index 000000000000..125994330437
--- /dev/null
+++ b/drivers/of/dynamic.c
@@ -0,0 +1,216 @@
+/*
+ * Support for dynamic device trees.
+ *
+ * On some platforms, the device tree can be manipulated at runtime.
+ * The routines in this section support adding, removing and changing
+ * device tree nodes.
+ */
+
+#include <linux/of.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/proc_fs.h>
+
+#include "of_private.h"
+
+/**
+ * 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);
+
+/**
+ * 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);
+
+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);
+}
+
+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);
+}
+
+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);
+}
+
+/**
+ * of_attach_node() - Plug a device node into the tree and global list.
+ */
+int of_attach_node(struct device_node *np)
+{
+ 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;
+
+ rc = of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np);
+ if (rc)
+ return rc;
+
+ raw_spin_lock_irqsave(&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 (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;
+ }
+
+ of_node_set_flag(np, OF_DETACHED);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+ of_node_remove(np);
+ return rc;
+}
+
+/**
+ * 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.
+ */
+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);
+}
diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
index fcc70e74dfe0..c270f2037779 100644
--- a/drivers/of/of_private.h
+++ b/drivers/of/of_private.h
@@ -33,4 +33,22 @@ struct alias_prop {

extern struct mutex of_mutex;
extern struct list_head aliases_lookup;
+
+static inline struct device_node *kobj_to_device_node(struct kobject *kobj)
+{
+ return container_of(kobj, struct device_node, kobj);
+}
+
+#if defined(CONFIG_OF_DYNAMIC)
+extern int of_property_notify(int action, struct device_node *np,
+ struct property *prop);
+extern void of_node_release(struct kobject *kobj);
+#else /* CONFIG_OF_DYNAMIC */
+static inline int of_property_notify(int action, struct device_node *np,
+ struct property *prop)
+{
+ return 0;
+}
+#endif /* CONFIG_OF_DYNAMIC */
+
#endif /* _LINUX_OF_PRIVATE_H */
--
1.9.1

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