of: Move CONFIG_OF_DYNAMIC code into a separate file

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@linaro.org>
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: Rob Herring <robh+dt@kernel.org>
This commit is contained in:
Grant Likely 2014-06-26 15:40:48 +01:00
parent c05aba2bd5
commit 6afc0dc381
4 changed files with 236 additions and 229 deletions

View File

@ -1,4 +1,5 @@
obj-y = base.o device.o platform.o obj-y = base.o device.o platform.o
obj-$(CONFIG_OF_DYNAMIC) += dynamic.o
obj-$(CONFIG_OF_FLATTREE) += fdt.o obj-$(CONFIG_OF_FLATTREE) += fdt.o
obj-$(CONFIG_OF_EARLY_FLATTREE) += fdt_address.o obj-$(CONFIG_OF_EARLY_FLATTREE) += fdt_address.o
obj-$(CONFIG_OF_PROMTREE) += pdt.o obj-$(CONFIG_OF_PROMTREE) += pdt.o

View File

@ -88,79 +88,7 @@ int __weak of_node_to_nid(struct device_node *np)
} }
#endif #endif
#if defined(CONFIG_OF_DYNAMIC) #ifndef 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
static void of_node_release(struct kobject *kobj) static void of_node_release(struct kobject *kobj)
{ {
/* Without CONFIG_OF_DYNAMIC, no nodes gets freed */ /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
@ -264,25 +192,6 @@ int of_node_add(struct device_node *np)
return rc; 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) static int __init of_init(void)
{ {
struct device_node *np; 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); 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 * __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; 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, static void of_alias_add(struct alias_prop *ap, struct device_node *np,
int id, const char *stem, int stem_len) int id, const char *stem, int stem_len)
{ {

216
drivers/of/dynamic.c Normal file
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@ -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);
}

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@ -33,4 +33,22 @@ struct alias_prop {
extern struct mutex of_mutex; extern struct mutex of_mutex;
extern struct list_head aliases_lookup; 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 */ #endif /* _LINUX_OF_PRIVATE_H */