linux/drivers/of/of_private.h
Frank Rowand 24789c5ce5 of: overlay: detect cases where device tree may become corrupt
When an attempt to apply an overlay changeset fails, an effort
is made to revert any partial application of the changeset.
When an attempt to remove an overlay changeset fails, an effort
is made to re-apply any partial reversion of the changeset.

The existing code does not check for failure to recover a failed
overlay changeset application or overlay changeset revert.

Add the missing checks and flag the devicetree as corrupt if the
state of the devicetree can not be determined.

Improve and expand the returned errors to more fully reflect the
result of the effort to undo the partial effects of a failed attempt
to apply or remove an overlay changeset.

If the device tree might be corrupt, do not allow further attempts
to apply or remove an overlay changeset.

When creating an overlay changeset from an overlay device tree,
add some additional warnings if the state of the overlay device
tree is not as expected.

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17 20:47:14 -05:00

134 lines
4.8 KiB
C

#ifndef _LINUX_OF_PRIVATE_H
#define _LINUX_OF_PRIVATE_H
/*
* Private symbols used by OF support code
*
* Paul Mackerras August 1996.
* Copyright (C) 1996-2005 Paul Mackerras.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
/**
* struct alias_prop - Alias property in 'aliases' node
* @link: List node to link the structure in aliases_lookup list
* @alias: Alias property name
* @np: Pointer to device_node that the alias stands for
* @id: Index value from end of alias name
* @stem: Alias string without the index
*
* The structure represents one alias property of 'aliases' node as
* an entry in aliases_lookup list.
*/
struct alias_prop {
struct list_head link;
const char *alias;
struct device_node *np;
int id;
char stem[0];
};
extern struct mutex of_mutex;
extern struct list_head aliases_lookup;
extern struct kset *of_kset;
#if defined(CONFIG_OF_DYNAMIC)
extern int of_property_notify(int action, struct device_node *np,
struct property *prop, struct property *old_prop);
extern void of_node_release(struct kobject *kobj);
extern int __of_changeset_apply_entries(struct of_changeset *ocs,
int *ret_revert);
extern int __of_changeset_apply_notify(struct of_changeset *ocs);
extern int __of_changeset_revert_entries(struct of_changeset *ocs,
int *ret_apply);
extern int __of_changeset_revert_notify(struct of_changeset *ocs);
#else /* CONFIG_OF_DYNAMIC */
static inline int of_property_notify(int action, struct device_node *np,
struct property *prop, struct property *old_prop)
{
return 0;
}
#endif /* CONFIG_OF_DYNAMIC */
#if defined(CONFIG_OF_KOBJ)
int of_node_is_attached(struct device_node *node);
int __of_add_property_sysfs(struct device_node *np, struct property *pp);
void __of_remove_property_sysfs(struct device_node *np, struct property *prop);
void __of_update_property_sysfs(struct device_node *np, struct property *newprop,
struct property *oldprop);
int __of_attach_node_sysfs(struct device_node *np);
void __of_detach_node_sysfs(struct device_node *np);
#else
static inline int __of_add_property_sysfs(struct device_node *np, struct property *pp)
{
return 0;
}
static inline void __of_remove_property_sysfs(struct device_node *np, struct property *prop) {}
static inline void __of_update_property_sysfs(struct device_node *np,
struct property *newprop, struct property *oldprop) {}
static inline int __of_attach_node_sysfs(struct device_node *np)
{
return 0;
}
static inline void __of_detach_node_sysfs(struct device_node *np) {}
#endif
#if defined(CONFIG_OF_UNITTEST) && defined(CONFIG_OF_OVERLAY)
extern void __init unittest_unflatten_overlay_base(void);
#else
static inline void unittest_unflatten_overlay_base(void) {};
#endif
extern void *__unflatten_device_tree(const void *blob,
struct device_node *dad,
struct device_node **mynodes,
void *(*dt_alloc)(u64 size, u64 align),
bool detached);
/**
* General utilities for working with live trees.
*
* All functions with two leading underscores operate
* without taking node references, so you either have to
* own the devtree lock or work on detached trees only.
*/
struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags);
__printf(2, 3) struct device_node *__of_node_dup(const struct device_node *np, const char *fmt, ...);
struct device_node *__of_find_node_by_full_path(struct device_node *node,
const char *path);
extern const void *__of_get_property(const struct device_node *np,
const char *name, int *lenp);
extern int __of_add_property(struct device_node *np, struct property *prop);
extern int __of_add_property_sysfs(struct device_node *np,
struct property *prop);
extern int __of_remove_property(struct device_node *np, struct property *prop);
extern void __of_remove_property_sysfs(struct device_node *np,
struct property *prop);
extern int __of_update_property(struct device_node *np,
struct property *newprop, struct property **oldprop);
extern void __of_update_property_sysfs(struct device_node *np,
struct property *newprop, struct property *oldprop);
extern int __of_attach_node_sysfs(struct device_node *np);
extern void __of_detach_node(struct device_node *np);
extern void __of_detach_node_sysfs(struct device_node *np);
extern void __of_sysfs_remove_bin_file(struct device_node *np,
struct property *prop);
/* iterators for transactions, used for overlays */
/* forward iterator */
#define for_each_transaction_entry(_oft, _te) \
list_for_each_entry(_te, &(_oft)->te_list, node)
/* reverse iterator */
#define for_each_transaction_entry_reverse(_oft, _te) \
list_for_each_entry_reverse(_te, &(_oft)->te_list, node)
#endif /* _LINUX_OF_PRIVATE_H */