The device tree data structure uses a custom linked list implemenation which is baroque and prone to bugs. Replace the child node lists with a list_head and the common list_head accessor functions.
Signed-off-by: Grant Likely <[email protected]> Cc: Rob Herring <[email protected]> --- drivers/of/base.c | 43 +++++++++++++++++++------------------------ drivers/of/fdt.c | 12 +++--------- include/linux/of.h | 8 +++++--- 3 files changed, 27 insertions(+), 36 deletions(-) diff --git a/drivers/of/base.c b/drivers/of/base.c index 6c0bd86b802f..69f5648babd8 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -47,6 +47,12 @@ static struct kset *of_kset; #define for_each_of_allnodes_continue(dn) \ list_for_each_entry_continue(dn, &of_allnodes, allnext) +#define of_children_prepare(parent, child) \ + list_prepare_entry(child, &parent->children, childnext) +#define for_each_of_children(parent, child) \ + list_for_each_entry(child, &parent->children, childnext) +#define for_each_of_children_continue(parent, child) \ + list_for_each_entry_continue(child, &parent->children, childnext) /* * Used to protect the of_aliases; but also overloaded to hold off addition of * nodes to sysfs @@ -711,11 +717,11 @@ static struct device_node *__of_get_next_child(const struct device_node *node, if (!node) return NULL; - next = prev ? prev->sibling : node->child; - for (; next; next = next->sibling) - if (of_node_get(next)) - break; of_node_put(prev); + next = list_next_entry(of_children_prepare(node, prev), childnext); + if (&next->childnext == &node->children) + next = NULL; + of_node_get(next); return next; } #define __for_each_child_of_node(parent, child) \ @@ -754,21 +760,21 @@ EXPORT_SYMBOL(of_get_next_child); struct device_node *of_get_next_available_child(const struct device_node *node, struct device_node *prev) { - struct device_node *next; + struct device_node *next = NULL; unsigned long flags; if (!node) return NULL; raw_spin_lock_irqsave(&devtree_lock, flags); - next = prev ? prev->sibling : node->child; - for (; next; next = next->sibling) { - if (!__of_device_is_available(next)) - continue; - if (of_node_get(next)) + of_node_put(prev); + prev = of_children_prepare(node, prev); + for_each_of_children_continue(node, prev) { + if (__of_device_is_available(prev)) { + next = of_node_get(prev); break; + } } - of_node_put(prev); raw_spin_unlock_irqrestore(&devtree_lock, flags); return next; } @@ -1976,8 +1982,7 @@ int of_attach_node(struct device_node *np) raw_spin_lock_irqsave(&devtree_lock, flags); list_add_tail(&np->allnext, &of_allnodes); - np->sibling = np->parent->child; - np->parent->child = np; + list_add_tail(&np->childnext, &np->parent->children); of_node_clear_flag(np, OF_DETACHED); raw_spin_unlock_irqrestore(&devtree_lock, flags); @@ -2016,17 +2021,7 @@ int of_detach_node(struct device_node *np) } list_del(&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; - } + list_del(&np->childnext); of_node_set_flag(np, OF_DETACHED); raw_spin_unlock_irqrestore(&devtree_lock, flags); diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 6876ac3d4b30..2ff96cac1496 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -155,6 +155,7 @@ static void * unflatten_dt_node(void *blob, char *fn; of_node_init(np); np->full_name = fn = ((char *)np) + sizeof(*np); + np->parent = dad; if (new_format) { /* rebuild full path for new format */ if (dad && dad->parent) { @@ -174,15 +175,8 @@ static void * unflatten_dt_node(void *blob, prev_pp = &np->properties; list_add_tail(&np->allnext, allnext); - if (dad != NULL) { - np->parent = dad; - /* we temporarily use the next field as `last_child'*/ - if (dad->next == NULL) - dad->child = np; - else - dad->next->sibling = np; - dad->next = np; - } + if (np->parent) + list_add_tail(&np->childnext, &np->parent->children); } /* process properties */ for (offset = fdt_first_property_offset(blob, *poffset); diff --git a/include/linux/of.h b/include/linux/of.h index e082db3c284f..11bef100bc43 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -52,10 +52,11 @@ struct device_node { struct property *properties; struct property *deadprops; /* removed properties */ + + struct list_head children; /* next device of same type */ struct device_node *parent; - struct device_node *child; - struct device_node *sibling; - struct device_node *next; /* next device of same type */ + + struct list_head childnext; struct list_head allnext; struct kobject kobj; unsigned long _flags; @@ -80,6 +81,7 @@ extern int of_node_add(struct device_node *node); extern struct kobj_type of_node_ktype; static inline void of_node_init(struct device_node *node) { + INIT_LIST_HEAD(&node->children); kobject_init(&node->kobj, &of_node_ktype); } -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
