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-rw-r--r--drivers/of/dynamic.c740
1 files changed, 524 insertions, 216 deletions
diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index 0542cf8b6e3d..2eaaddcb0ec4 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* Support for dynamic device trees.
*
@@ -8,6 +9,8 @@
#define pr_fmt(fmt) "OF: " fmt
+#include <linux/cleanup.h>
+#include <linux/device.h>
#include <linux/of.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
@@ -16,12 +19,17 @@
#include "of_private.h"
+static struct device_node *kobj_to_device_node(struct kobject *kobj)
+{
+ return container_of(kobj, struct device_node, kobj);
+}
+
/**
* of_node_get() - Increment refcount of a node
* @node: Node to inc refcount, NULL is supported to simplify writing of
* callers
*
- * Returns node.
+ * Return: The node with refcount incremented.
*/
struct device_node *of_node_get(struct device_node *node)
{
@@ -43,28 +51,6 @@ void of_node_put(struct device_node *node)
}
EXPORT_SYMBOL(of_node_put);
-void __of_detach_node_sysfs(struct device_node *np)
-{
- struct property *pp;
-
- if (!IS_ENABLED(CONFIG_SYSFS))
- return;
-
- BUG_ON(!of_node_is_initialized(np));
- if (!of_kset)
- return;
-
- /* only remove properties if on sysfs */
- if (of_node_is_attached(np)) {
- for_each_property_of_node(np, pp)
- __of_sysfs_remove_bin_file(np, pp);
- 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)
@@ -79,37 +65,30 @@ int of_reconfig_notifier_unregister(struct notifier_block *nb)
}
EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister);
-#ifdef DEBUG
-const char *action_names[] = {
+static const char *action_names[] = {
+ [0] = "INVALID",
[OF_RECONFIG_ATTACH_NODE] = "ATTACH_NODE",
[OF_RECONFIG_DETACH_NODE] = "DETACH_NODE",
[OF_RECONFIG_ADD_PROPERTY] = "ADD_PROPERTY",
[OF_RECONFIG_REMOVE_PROPERTY] = "REMOVE_PROPERTY",
[OF_RECONFIG_UPDATE_PROPERTY] = "UPDATE_PROPERTY",
};
-#endif
+
+#define _do_print(func, prefix, action, node, prop, ...) ({ \
+ func("changeset: " prefix "%-15s %pOF%s%s\n", \
+ ##__VA_ARGS__, action_names[action], node, \
+ prop ? ":" : "", prop ? prop->name : ""); \
+})
+#define of_changeset_action_err(...) _do_print(pr_err, __VA_ARGS__)
+#define of_changeset_action_debug(...) _do_print(pr_debug, __VA_ARGS__)
int of_reconfig_notify(unsigned long action, struct of_reconfig_data *p)
{
int rc;
-#ifdef DEBUG
struct of_reconfig_data *pr = p;
- switch (action) {
- case OF_RECONFIG_ATTACH_NODE:
- case OF_RECONFIG_DETACH_NODE:
- pr_debug("notify %-15s %s\n", action_names[action],
- pr->dn->full_name);
- break;
- case OF_RECONFIG_ADD_PROPERTY:
- case OF_RECONFIG_REMOVE_PROPERTY:
- case OF_RECONFIG_UPDATE_PROPERTY:
- pr_debug("notify %-15s %s:%s\n", action_names[action],
- pr->dn->full_name, pr->prop->name);
- break;
+ of_changeset_action_debug("notify: ", action, pr->dn, pr->prop);
- }
-#endif
rc = blocking_notifier_call_chain(&of_reconfig_chain, action, p);
return notifier_to_errno(rc);
}
@@ -120,8 +99,10 @@ int of_reconfig_notify(unsigned long action, struct of_reconfig_data *p)
* @arg - argument of the of notifier
*
* Returns the new state of a device based on the notifier used.
- * Returns 0 on device going from enabled to disabled, 1 on device
- * going from disabled to enabled and -1 on no change.
+ *
+ * Return: OF_RECONFIG_CHANGE_REMOVE on device going from enabled to
+ * disabled, OF_RECONFIG_CHANGE_ADD on device going from disabled to
+ * enabled and OF_RECONFIG_NO_CHANGE on no change.
*/
int of_reconfig_get_state_change(unsigned long action, struct of_reconfig_data *pr)
{
@@ -220,40 +201,50 @@ static void __of_attach_node(struct device_node *np)
{
const __be32 *phandle;
int sz;
+ unsigned long flags;
- np->name = __of_get_property(np, "name", NULL) ? : "<NULL>";
- np->type = __of_get_property(np, "device_type", NULL) ? : "<NULL>";
+ raw_spin_lock_irqsave(&devtree_lock, flags);
- phandle = __of_get_property(np, "phandle", &sz);
- if (!phandle)
- phandle = __of_get_property(np, "linux,phandle", &sz);
- if (IS_ENABLED(CONFIG_PPC_PSERIES) && !phandle)
- phandle = __of_get_property(np, "ibm,phandle", &sz);
- np->phandle = (phandle && (sz >= 4)) ? be32_to_cpup(phandle) : 0;
+ if (!of_node_check_flag(np, OF_OVERLAY)) {
+ np->name = __of_get_property(np, "name", NULL);
+ if (!np->name)
+ np->name = "<NULL>";
+
+ phandle = __of_get_property(np, "phandle", &sz);
+ if (!phandle)
+ phandle = __of_get_property(np, "linux,phandle", &sz);
+ if (IS_ENABLED(CONFIG_PPC_PSERIES) && !phandle)
+ phandle = __of_get_property(np, "ibm,phandle", &sz);
+ if (phandle && (sz >= 4))
+ np->phandle = be32_to_cpup(phandle);
+ else
+ np->phandle = 0;
+ }
np->child = NULL;
np->sibling = np->parent->child;
np->parent->child = np;
of_node_clear_flag(np, OF_DETACHED);
+ np->fwnode.flags |= FWNODE_FLAG_NOT_DEVICE;
+
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+ __of_attach_node_sysfs(np);
}
/**
* of_attach_node() - Plug a device node into the tree and global list.
+ * @np: Pointer to the caller's Device Node
*/
int of_attach_node(struct device_node *np)
{
struct of_reconfig_data rd;
- unsigned long flags;
memset(&rd, 0, sizeof(rd));
rd.dn = np;
mutex_lock(&of_mutex);
- raw_spin_lock_irqsave(&devtree_lock, flags);
__of_attach_node(np);
- raw_spin_unlock_irqrestore(&devtree_lock, flags);
-
- __of_attach_node_sysfs(np);
mutex_unlock(&of_mutex);
of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, &rd);
@@ -264,13 +255,15 @@ int of_attach_node(struct device_node *np)
void __of_detach_node(struct device_node *np)
{
struct device_node *parent;
+ unsigned long flags;
- if (WARN_ON(of_node_check_flag(np, OF_DETACHED)))
- return;
+ raw_spin_lock_irqsave(&devtree_lock, flags);
parent = np->parent;
- if (WARN_ON(!parent))
+ if (WARN_ON(of_node_check_flag(np, OF_DETACHED) || !parent)) {
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return;
+ }
if (parent->child == np)
parent->child = np->sibling;
@@ -284,70 +277,119 @@ void __of_detach_node(struct device_node *np)
}
of_node_set_flag(np, OF_DETACHED);
+
+ /* race with of_find_node_by_phandle() prevented by devtree_lock */
+ __of_phandle_cache_inv_entry(np->phandle);
+
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+ __of_detach_node_sysfs(np);
}
/**
* 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.
+ * @np: Pointer to the caller's Device Node
*/
int of_detach_node(struct device_node *np)
{
struct of_reconfig_data rd;
- unsigned long flags;
- int rc = 0;
memset(&rd, 0, sizeof(rd));
rd.dn = np;
mutex_lock(&of_mutex);
- raw_spin_lock_irqsave(&devtree_lock, flags);
__of_detach_node(np);
- raw_spin_unlock_irqrestore(&devtree_lock, flags);
-
- __of_detach_node_sysfs(np);
mutex_unlock(&of_mutex);
of_reconfig_notify(OF_RECONFIG_DETACH_NODE, &rd);
- return rc;
+ return 0;
}
EXPORT_SYMBOL_GPL(of_detach_node);
+void __of_prop_free(struct property *prop)
+{
+ kfree(prop->name);
+ kfree(prop->value);
+ kfree(prop);
+}
+
+static void property_list_free(struct property *prop_list)
+{
+ struct property *prop, *next;
+
+ for (prop = prop_list; prop != NULL; prop = next) {
+ next = prop->next;
+ __of_prop_free(prop);
+ }
+}
+
/**
* of_node_release() - release a dynamically allocated node
- * @kref: kref element of the node to be released
+ * @kobj: kernel object 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;
+
+ /*
+ * can not use '"%pOF", node' in pr_err() calls from this function
+ * because an of_node_get(node) when refcount is already zero
+ * will result in an error and a stack dump
+ */
/* 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();
+
+ pr_err("ERROR: %s() detected bad of_node_put() on %pOF/%s\n",
+ __func__, node->parent, node->full_name);
+
+ /*
+ * of unittests will test this path. Do not print the stack
+ * trace when the error is caused by unittest so that we do
+ * not display what a normal developer might reasonably
+ * consider a real bug.
+ */
+ if (!IS_ENABLED(CONFIG_OF_UNITTEST) ||
+ strcmp(node->parent->full_name, "testcase-data")) {
+ dump_stack();
+ pr_err("ERROR: next of_node_put() on this node will result in a kobject warning 'refcount_t: underflow; use-after-free.'\n");
+ }
+
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 (of_node_check_flag(node, OF_OVERLAY)) {
- if (!prop) {
- prop = node->deadprops;
- node->deadprops = NULL;
+ if (!of_node_check_flag(node, OF_OVERLAY_FREE_CSET)) {
+ /* premature refcount of zero, do not free memory */
+ pr_err("ERROR: memory leak before free overlay changeset, %pOF\n",
+ node);
+ return;
}
+
+ /*
+ * If node->properties non-empty then properties were added
+ * to this node either by different overlay that has not
+ * yet been removed, or by a non-overlay mechanism.
+ */
+ if (node->properties)
+ pr_err("ERROR: %s(), unexpected properties in %pOF\n",
+ __func__, node);
}
+
+ if (node->child)
+ pr_err("ERROR: %s() unexpected children for %pOF/%s\n",
+ __func__, node->parent, node->full_name);
+
+ property_list_free(node->properties);
+ property_list_free(node->deadprops);
+ fwnode_links_purge(of_fwnode_handle(node));
+
kfree(node->full_name);
kfree(node->data);
kfree(node);
@@ -362,7 +404,8 @@ void of_node_release(struct kobject *kobj)
* property structure and the property name & contents. The property's
* flags have the OF_DYNAMIC bit set so that we can differentiate between
* dynamically allocated properties and not.
- * Returns the newly allocated property or NULL on out of memory error.
+ *
+ * Return: The newly allocated property or NULL on out of memory error.
*/
struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags)
{
@@ -390,33 +433,31 @@ struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags)
return new;
err_free:
- kfree(new->name);
- kfree(new->value);
- kfree(new);
+ __of_prop_free(new);
return NULL;
}
/**
* __of_node_dup() - Duplicate or create an empty device node dynamically.
- * @fmt: Format string (plus vargs) for new full name of the device node
+ * @np: if not NULL, contains properties to be duplicated in new node
+ * @full_name: string value to be duplicated into new node's full_name field
+ *
+ * Create a device tree node, optionally duplicating the properties of
+ * another node. The node data are dynamically allocated and all the node
+ * flags have the OF_DYNAMIC & OF_DETACHED bits set.
*
- * Create an device tree node, either by duplicating an empty node or by allocating
- * an empty one suitable for further modification. The node data are
- * dynamically allocated and all the node flags have the OF_DYNAMIC &
- * OF_DETACHED bits set. Returns the newly allocated node or NULL on out of
- * memory error.
+ * Return: The newly allocated node or NULL on out of memory error. Use
+ * of_node_put() on it when done to free the memory allocated for it.
*/
-struct device_node *__of_node_dup(const struct device_node *np, const char *fmt, ...)
+struct device_node *__of_node_dup(const struct device_node *np,
+ const char *full_name)
{
- va_list vargs;
struct device_node *node;
node = kzalloc(sizeof(*node), GFP_KERNEL);
if (!node)
return NULL;
- va_start(vargs, fmt);
- node->full_name = kvasprintf(GFP_KERNEL, fmt, vargs);
- va_end(vargs);
+ node->full_name = kstrdup(full_name, GFP_KERNEL);
if (!node->full_name) {
kfree(node);
return NULL;
@@ -434,9 +475,7 @@ struct device_node *__of_node_dup(const struct device_node *np, const char *fmt,
if (!new_pp)
goto err_prop;
if (__of_add_property(node, new_pp)) {
- kfree(new_pp->name);
- kfree(new_pp->value);
- kfree(new_pp);
+ __of_prop_free(new_pp);
goto err_prop;
}
}
@@ -448,38 +487,56 @@ struct device_node *__of_node_dup(const struct device_node *np, const char *fmt,
return NULL;
}
-static void __of_changeset_entry_destroy(struct of_changeset_entry *ce)
+/**
+ * of_changeset_create_node - Dynamically create a device node and attach to
+ * a given changeset.
+ *
+ * @ocs: Pointer to changeset
+ * @parent: Pointer to parent device node
+ * @full_name: Node full name
+ *
+ * Return: Pointer to the created device node or NULL in case of an error.
+ */
+struct device_node *of_changeset_create_node(struct of_changeset *ocs,
+ struct device_node *parent,
+ const char *full_name)
{
- of_node_put(ce->np);
- list_del(&ce->node);
- kfree(ce);
-}
+ struct device_node *np;
+ int ret;
-#ifdef DEBUG
-static void __of_changeset_entry_dump(struct of_changeset_entry *ce)
-{
- switch (ce->action) {
- case OF_RECONFIG_ADD_PROPERTY:
- case OF_RECONFIG_REMOVE_PROPERTY:
- case OF_RECONFIG_UPDATE_PROPERTY:
- pr_debug("cset<%p> %-15s %s/%s\n", ce, action_names[ce->action],
- ce->np->full_name, ce->prop->name);
- break;
- case OF_RECONFIG_ATTACH_NODE:
- case OF_RECONFIG_DETACH_NODE:
- pr_debug("cset<%p> %-15s %s\n", ce, action_names[ce->action],
- ce->np->full_name);
- break;
+ np = __of_node_dup(NULL, full_name);
+ if (!np)
+ return NULL;
+ np->parent = parent;
+
+ ret = of_changeset_attach_node(ocs, np);
+ if (ret) {
+ of_node_put(np);
+ return NULL;
}
+
+ return np;
}
-#else
-static inline void __of_changeset_entry_dump(struct of_changeset_entry *ce)
+EXPORT_SYMBOL(of_changeset_create_node);
+
+static void __of_changeset_entry_destroy(struct of_changeset_entry *ce)
{
- /* empty */
+ if (ce->action == OF_RECONFIG_ATTACH_NODE &&
+ of_node_check_flag(ce->np, OF_OVERLAY)) {
+ if (kref_read(&ce->np->kobj.kref) > 1) {
+ pr_err("ERROR: memory leak, expected refcount 1 instead of %d, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node %pOF\n",
+ kref_read(&ce->np->kobj.kref), ce->np);
+ } else {
+ of_node_set_flag(ce->np, OF_OVERLAY_FREE_CSET);
+ }
+ }
+
+ of_node_put(ce->np);
+ list_del(&ce->node);
+ kfree(ce);
}
-#endif
-static void __of_changeset_entry_invert(struct of_changeset_entry *ce,
+static void __of_changeset_entry_invert(const struct of_changeset_entry *ce,
struct of_changeset_entry *rce)
{
memcpy(rce, ce, sizeof(*rce));
@@ -509,11 +566,12 @@ static void __of_changeset_entry_invert(struct of_changeset_entry *ce,
}
}
-static void __of_changeset_entry_notify(struct of_changeset_entry *ce, bool revert)
+static int __of_changeset_entry_notify(struct of_changeset_entry *ce,
+ bool revert)
{
struct of_reconfig_data rd;
struct of_changeset_entry ce_inverted;
- int ret;
+ int ret = 0;
if (revert) {
__of_changeset_entry_invert(ce, &ce_inverted);
@@ -535,22 +593,20 @@ static void __of_changeset_entry_notify(struct of_changeset_entry *ce, bool reve
default:
pr_err("invalid devicetree changeset action: %i\n",
(int)ce->action);
- return;
+ ret = -EINVAL;
}
if (ret)
- pr_err("changeset notifier error @%s\n", ce->np->full_name);
+ pr_err("changeset notifier error @%pOF\n", ce->np);
+ return ret;
}
static int __of_changeset_entry_apply(struct of_changeset_entry *ce)
{
- struct property *old_prop, **propp;
- unsigned long flags;
int ret = 0;
- __of_changeset_entry_dump(ce);
+ of_changeset_action_debug("apply: ", ce->action, ce->np, ce->prop);
- raw_spin_lock_irqsave(&devtree_lock, flags);
switch (ce->action) {
case OF_RECONFIG_ATTACH_NODE:
__of_attach_node(ce->np);
@@ -559,82 +615,28 @@ static int __of_changeset_entry_apply(struct of_changeset_entry *ce)
__of_detach_node(ce->np);
break;
case OF_RECONFIG_ADD_PROPERTY:
- /* If the property is in deadprops then it must be removed */
- for (propp = &ce->np->deadprops; *propp; propp = &(*propp)->next) {
- if (*propp == ce->prop) {
- *propp = ce->prop->next;
- ce->prop->next = NULL;
- break;
- }
- }
-
ret = __of_add_property(ce->np, ce->prop);
- if (ret) {
- pr_err("changeset: add_property failed @%s/%s\n",
- ce->np->full_name,
- ce->prop->name);
- break;
- }
break;
case OF_RECONFIG_REMOVE_PROPERTY:
ret = __of_remove_property(ce->np, ce->prop);
- if (ret) {
- pr_err("changeset: remove_property failed @%s/%s\n",
- ce->np->full_name,
- ce->prop->name);
- break;
- }
break;
case OF_RECONFIG_UPDATE_PROPERTY:
- /* If the property is in deadprops then it must be removed */
- for (propp = &ce->np->deadprops; *propp; propp = &(*propp)->next) {
- if (*propp == ce->prop) {
- *propp = ce->prop->next;
- ce->prop->next = NULL;
- break;
- }
- }
-
- ret = __of_update_property(ce->np, ce->prop, &old_prop);
- if (ret) {
- pr_err("changeset: update_property failed @%s/%s\n",
- ce->np->full_name,
- ce->prop->name);
- break;
- }
+ ret = __of_update_property(ce->np, ce->prop, &ce->old_prop);
break;
default:
ret = -EINVAL;
}
- raw_spin_unlock_irqrestore(&devtree_lock, flags);
- if (ret)
+ if (ret) {
+ of_changeset_action_err("apply failed: ", ce->action, ce->np, ce->prop);
return ret;
-
- switch (ce->action) {
- case OF_RECONFIG_ATTACH_NODE:
- __of_attach_node_sysfs(ce->np);
- break;
- case OF_RECONFIG_DETACH_NODE:
- __of_detach_node_sysfs(ce->np);
- break;
- case OF_RECONFIG_ADD_PROPERTY:
- /* ignore duplicate names */
- __of_add_property_sysfs(ce->np, ce->prop);
- break;
- case OF_RECONFIG_REMOVE_PROPERTY:
- __of_remove_property_sysfs(ce->np, ce->prop);
- break;
- case OF_RECONFIG_UPDATE_PROPERTY:
- __of_update_property_sysfs(ce->np, ce->prop, ce->old_prop);
- break;
}
return 0;
}
-static inline int __of_changeset_entry_revert(struct of_changeset_entry *ce)
+static inline int __of_changeset_entry_revert(const struct of_changeset_entry *ce)
{
struct of_changeset_entry ce_inverted;
@@ -668,37 +670,98 @@ void of_changeset_destroy(struct of_changeset *ocs)
{
struct of_changeset_entry *ce, *cen;
+ /*
+ * When a device is deleted, the device links to/from it are also queued
+ * for deletion. Until these device links are freed, the devices
+ * themselves aren't freed. If the device being deleted is due to an
+ * overlay change, this device might be holding a reference to a device
+ * node that will be freed. So, wait until all already pending device
+ * links are deleted before freeing a device node. This ensures we don't
+ * free any device node that has a non-zero reference count.
+ */
+ device_link_wait_removal();
+
list_for_each_entry_safe_reverse(ce, cen, &ocs->entries, node)
__of_changeset_entry_destroy(ce);
}
EXPORT_SYMBOL_GPL(of_changeset_destroy);
-int __of_changeset_apply(struct of_changeset *ocs)
+/*
+ * Apply the changeset entries in @ocs.
+ * If apply fails, an attempt is made to revert the entries that were
+ * successfully applied.
+ *
+ * If multiple revert errors occur then only the final revert error is reported.
+ *
+ * Returns 0 on success, a negative error value in case of an error.
+ * If a revert error occurs, it is returned in *ret_revert.
+ */
+int __of_changeset_apply_entries(struct of_changeset *ocs, int *ret_revert)
{
struct of_changeset_entry *ce;
- int ret;
+ int ret, ret_tmp;
- /* perform the rest of the work */
pr_debug("changeset: applying...\n");
list_for_each_entry(ce, &ocs->entries, node) {
ret = __of_changeset_entry_apply(ce);
if (ret) {
pr_err("Error applying changeset (%d)\n", ret);
- list_for_each_entry_continue_reverse(ce, &ocs->entries, node)
- __of_changeset_entry_revert(ce);
+ list_for_each_entry_continue_reverse(ce, &ocs->entries,
+ node) {
+ ret_tmp = __of_changeset_entry_revert(ce);
+ if (ret_tmp)
+ *ret_revert = ret_tmp;
+ }
return ret;
}
}
- pr_debug("changeset: applied, emitting notifiers.\n");
+
+ return 0;
+}
+
+/*
+ * Returns 0 on success, a negative error value in case of an error.
+ *
+ * If multiple changeset entry notification errors occur then only the
+ * final notification error is reported.
+ */
+int __of_changeset_apply_notify(struct of_changeset *ocs)
+{
+ struct of_changeset_entry *ce;
+ int ret = 0, ret_tmp;
+
+ pr_debug("changeset: emitting notifiers.\n");
/* drop the global lock while emitting notifiers */
mutex_unlock(&of_mutex);
- list_for_each_entry(ce, &ocs->entries, node)
- __of_changeset_entry_notify(ce, 0);
+ list_for_each_entry(ce, &ocs->entries, node) {
+ ret_tmp = __of_changeset_entry_notify(ce, 0);
+ if (ret_tmp)
+ ret = ret_tmp;
+ }
mutex_lock(&of_mutex);
pr_debug("changeset: notifiers sent.\n");
- return 0;
+ return ret;
+}
+
+/*
+ * Returns 0 on success, a negative error value in case of an error.
+ *
+ * If a changeset entry apply fails, an attempt is made to revert any
+ * previous entries in the changeset. If any of the reverts fails,
+ * that failure is not reported. Thus the state of the device tree
+ * is unknown if an apply error occurs.
+ */
+static int __of_changeset_apply(struct of_changeset *ocs)
+{
+ int ret, ret_revert = 0;
+
+ ret = __of_changeset_apply_entries(ocs, &ret_revert);
+ if (!ret)
+ ret = __of_changeset_apply_notify(ocs);
+
+ return ret;
}
/**
@@ -710,7 +773,8 @@ int __of_changeset_apply(struct of_changeset *ocs)
* Any side-effects of live tree state changes are applied here on
* success, like creation/destruction of devices and side-effects
* like creation of sysfs properties and directories.
- * Returns 0 on success, a negative error value in case of an error.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
* On error the partially applied effects are reverted.
*/
int of_changeset_apply(struct of_changeset *ocs)
@@ -725,31 +789,74 @@ int of_changeset_apply(struct of_changeset *ocs)
}
EXPORT_SYMBOL_GPL(of_changeset_apply);
-int __of_changeset_revert(struct of_changeset *ocs)
+/*
+ * Revert the changeset entries in @ocs.
+ * If revert fails, an attempt is made to re-apply the entries that were
+ * successfully removed.
+ *
+ * If multiple re-apply errors occur then only the final apply error is
+ * reported.
+ *
+ * Returns 0 on success, a negative error value in case of an error.
+ * If an apply error occurs, it is returned in *ret_apply.
+ */
+int __of_changeset_revert_entries(struct of_changeset *ocs, int *ret_apply)
{
struct of_changeset_entry *ce;
- int ret;
+ int ret, ret_tmp;
pr_debug("changeset: reverting...\n");
list_for_each_entry_reverse(ce, &ocs->entries, node) {
ret = __of_changeset_entry_revert(ce);
if (ret) {
pr_err("Error reverting changeset (%d)\n", ret);
- list_for_each_entry_continue(ce, &ocs->entries, node)
- __of_changeset_entry_apply(ce);
+ list_for_each_entry_continue(ce, &ocs->entries, node) {
+ ret_tmp = __of_changeset_entry_apply(ce);
+ if (ret_tmp)
+ *ret_apply = ret_tmp;
+ }
return ret;
}
}
- pr_debug("changeset: reverted, emitting notifiers.\n");
+
+ return 0;
+}
+
+/*
+ * If multiple changeset entry notification errors occur then only the
+ * final notification error is reported.
+ */
+int __of_changeset_revert_notify(struct of_changeset *ocs)
+{
+ struct of_changeset_entry *ce;
+ int ret = 0, ret_tmp;
+
+ pr_debug("changeset: emitting notifiers.\n");
/* drop the global lock while emitting notifiers */
mutex_unlock(&of_mutex);
- list_for_each_entry_reverse(ce, &ocs->entries, node)
- __of_changeset_entry_notify(ce, 1);
+ list_for_each_entry_reverse(ce, &ocs->entries, node) {
+ ret_tmp = __of_changeset_entry_notify(ce, 1);
+ if (ret_tmp)
+ ret = ret_tmp;
+ }
mutex_lock(&of_mutex);
pr_debug("changeset: notifiers sent.\n");
- return 0;
+ return ret;
+}
+
+static int __of_changeset_revert(struct of_changeset *ocs)
+{
+ int ret, ret_reply;
+
+ ret_reply = 0;
+ ret = __of_changeset_revert_entries(ocs, &ret_reply);
+
+ if (!ret)
+ ret = __of_changeset_revert_notify(ocs);
+
+ return ret;
}
/**
@@ -761,7 +868,8 @@ int __of_changeset_revert(struct of_changeset *ocs)
* was before the application.
* Any side-effects like creation/destruction of devices and
* removal of sysfs properties and directories are applied.
- * Returns 0 on success, a negative error value in case of an error.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
*/
int of_changeset_revert(struct of_changeset *ocs)
{
@@ -776,7 +884,7 @@ int of_changeset_revert(struct of_changeset *ocs)
EXPORT_SYMBOL_GPL(of_changeset_revert);
/**
- * of_changeset_action - Perform a changeset action
+ * of_changeset_action - Add an action to the tail of the changeset list
*
* @ocs: changeset pointer
* @action: action to perform
@@ -789,13 +897,17 @@ EXPORT_SYMBOL_GPL(of_changeset_revert);
* + OF_RECONFIG_ADD_PROPERTY
* + OF_RECONFIG_REMOVE_PROPERTY,
* + OF_RECONFIG_UPDATE_PROPERTY
- * Returns 0 on success, a negative error value in case of an error.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
*/
int of_changeset_action(struct of_changeset *ocs, unsigned long action,
struct device_node *np, struct property *prop)
{
struct of_changeset_entry *ce;
+ if (WARN_ON(action >= ARRAY_SIZE(action_names)))
+ return -EINVAL;
+
ce = kzalloc(sizeof(*ce), GFP_KERNEL);
if (!ce)
return -ENOMEM;
@@ -805,11 +917,207 @@ int of_changeset_action(struct of_changeset *ocs, unsigned long action,
ce->np = of_node_get(np);
ce->prop = prop;
- if (action == OF_RECONFIG_UPDATE_PROPERTY && prop)
- ce->old_prop = of_find_property(np, prop->name, NULL);
-
/* add it to the list */
list_add_tail(&ce->node, &ocs->entries);
return 0;
}
EXPORT_SYMBOL_GPL(of_changeset_action);
+
+static int of_changeset_add_prop_helper(struct of_changeset *ocs,
+ struct device_node *np,
+ const struct property *pp)
+{
+ struct property *new_pp;
+ int ret;
+
+ new_pp = __of_prop_dup(pp, GFP_KERNEL);
+ if (!new_pp)
+ return -ENOMEM;
+
+ ret = of_changeset_add_property(ocs, np, new_pp);
+ if (ret) {
+ __of_prop_free(new_pp);
+ return ret;
+ }
+
+ new_pp->next = np->deadprops;
+ np->deadprops = new_pp;
+
+ return 0;
+}
+
+/**
+ * of_changeset_add_prop_string - Add a string property to a changeset
+ *
+ * @ocs: changeset pointer
+ * @np: device node pointer
+ * @prop_name: name of the property to be added
+ * @str: pointer to null terminated string
+ *
+ * Create a string property and add it to a changeset.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_add_prop_string(struct of_changeset *ocs,
+ struct device_node *np,
+ const char *prop_name, const char *str)
+{
+ struct property prop;
+
+ prop.name = (char *)prop_name;
+ prop.length = strlen(str) + 1;
+ prop.value = (void *)str;
+
+ return of_changeset_add_prop_helper(ocs, np, &prop);
+}
+EXPORT_SYMBOL_GPL(of_changeset_add_prop_string);
+
+/**
+ * of_changeset_add_prop_string_array - Add a string list property to
+ * a changeset
+ *
+ * @ocs: changeset pointer
+ * @np: device node pointer
+ * @prop_name: name of the property to be added
+ * @str_array: pointer to an array of null terminated strings
+ * @sz: number of string array elements
+ *
+ * Create a string list property and add it to a changeset.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_add_prop_string_array(struct of_changeset *ocs,
+ struct device_node *np,
+ const char *prop_name,
+ const char * const *str_array, size_t sz)
+{
+ struct property prop;
+ int i, ret;
+ char *vp;
+
+ prop.name = (char *)prop_name;
+
+ prop.length = 0;
+ for (i = 0; i < sz; i++)
+ prop.length += strlen(str_array[i]) + 1;
+
+ prop.value = kmalloc(prop.length, GFP_KERNEL);
+ if (!prop.value)
+ return -ENOMEM;
+
+ vp = prop.value;
+ for (i = 0; i < sz; i++) {
+ vp += snprintf(vp, (char *)prop.value + prop.length - vp, "%s",
+ str_array[i]) + 1;
+ }
+ ret = of_changeset_add_prop_helper(ocs, np, &prop);
+ kfree(prop.value);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_changeset_add_prop_string_array);
+
+/**
+ * of_changeset_add_prop_u32_array - Add a property of 32 bit integers
+ * property to a changeset
+ *
+ * @ocs: changeset pointer
+ * @np: device node pointer
+ * @prop_name: name of the property to be added
+ * @array: pointer to an array of 32 bit integers
+ * @sz: number of array elements
+ *
+ * Create a property of 32 bit integers and add it to a changeset.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_add_prop_u32_array(struct of_changeset *ocs,
+ struct device_node *np,
+ const char *prop_name,
+ const u32 *array, size_t sz)
+{
+ struct property prop;
+ __be32 *val __free(kfree) = kcalloc(sz, sizeof(__be32), GFP_KERNEL);
+ int i;
+
+ if (!val)
+ return -ENOMEM;
+
+ for (i = 0; i < sz; i++)
+ val[i] = cpu_to_be32(array[i]);
+ prop.name = (char *)prop_name;
+ prop.length = sizeof(u32) * sz;
+ prop.value = (void *)val;
+
+ return of_changeset_add_prop_helper(ocs, np, &prop);
+}
+EXPORT_SYMBOL_GPL(of_changeset_add_prop_u32_array);
+
+/**
+ * of_changeset_add_prop_bool - Add a boolean property (i.e. a property without
+ * any values) to a changeset.
+ *
+ * @ocs: changeset pointer
+ * @np: device node pointer
+ * @prop_name: name of the property to be added
+ *
+ * Create a boolean property and add it to a changeset.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_add_prop_bool(struct of_changeset *ocs, struct device_node *np,
+ const char *prop_name)
+{
+ struct property prop;
+
+ prop.name = (char *)prop_name;
+ prop.length = 0;
+ prop.value = NULL;
+
+ return of_changeset_add_prop_helper(ocs, np, &prop);
+}
+EXPORT_SYMBOL_GPL(of_changeset_add_prop_bool);
+
+static int of_changeset_update_prop_helper(struct of_changeset *ocs,
+ struct device_node *np,
+ const struct property *pp)
+{
+ struct property *new_pp;
+ int ret;
+
+ new_pp = __of_prop_dup(pp, GFP_KERNEL);
+ if (!new_pp)
+ return -ENOMEM;
+
+ ret = of_changeset_update_property(ocs, np, new_pp);
+ if (ret)
+ __of_prop_free(new_pp);
+
+ return ret;
+}
+
+/**
+ * of_changeset_update_prop_string - Add a string property update to a changeset
+ *
+ * @ocs: changeset pointer
+ * @np: device node pointer
+ * @prop_name: name of the property to be updated
+ * @str: pointer to null terminated string
+ *
+ * Create a string property to be updated and add it to a changeset.
+ *
+ * Return: 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_update_prop_string(struct of_changeset *ocs,
+ struct device_node *np,
+ const char *prop_name, const char *str)
+{
+ struct property prop = {
+ .name = (char *)prop_name,
+ .length = strlen(str) + 1,
+ .value = (void *)str,
+ };
+
+ return of_changeset_update_prop_helper(ocs, np, &prop);
+}
+EXPORT_SYMBOL_GPL(of_changeset_update_prop_string);