From e5efaeb8a8f527d6e91289ff1f67fbcae452b2ca Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Wed, 2 Jun 2021 17:19:07 +0900 Subject: bootconfig: Support mixing a value and subkeys under a key Support mixing a value and subkeys under a key. Since kernel cmdline options will support "aaa.bbb=value1 aaa.bbb.ccc=value2", it is better that the bootconfig supports such configuration too. Note that this does not change syntax itself but just accepts mixed value and subkeys e.g. key = value1 key.subkey = value2 But this is not accepted; key { value1 subkey = value2 } That will make value1 as a subkey. Also, the order of the value node under a key is fixed. If there are a value and subkeys, the value is always the first child node of the key. Thus if user specifies subkeys first, e.g. key.subkey = value1 key = value2 In the program (and /proc/bootconfig), it will be shown as below key = value2 key.subkey = value1 Link: https://lkml.kernel.org/r/162262194685.264090.7738574774030567419.stgit@devnote2 Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- include/linux/bootconfig.h | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) (limited to 'include/linux') diff --git a/include/linux/bootconfig.h b/include/linux/bootconfig.h index 3178a31fdabc..e49043ac77c9 100644 --- a/include/linux/bootconfig.h +++ b/include/linux/bootconfig.h @@ -80,6 +80,8 @@ static inline __init bool xbc_node_is_array(struct xbc_node *node) * * Test the @node is a leaf key node which is a key node and has a value node * or no child. Returns true if it is a leaf node, or false if not. + * Note that the leaf node can have subkey nodes in addition to the + * value node. */ static inline __init bool xbc_node_is_leaf(struct xbc_node *node) { @@ -129,6 +131,23 @@ static inline struct xbc_node * __init xbc_find_node(const char *key) return xbc_node_find_child(NULL, key); } +/** + * xbc_node_get_subkey() - Return the first subkey node if exists + * @node: Parent node + * + * Return the first subkey node of the @node. If the @node has no child + * or only value node, this will return NULL. + */ +static inline struct xbc_node * __init xbc_node_get_subkey(struct xbc_node *node) +{ + struct xbc_node *child = xbc_node_get_child(node); + + if (child && xbc_node_is_value(child)) + return xbc_node_get_next(child); + else + return child; +} + /** * xbc_array_for_each_value() - Iterate value nodes on an array * @anode: An XBC arraied value node @@ -149,11 +168,24 @@ static inline struct xbc_node * __init xbc_find_node(const char *key) * @child: Iterated XBC node. * * Iterate child nodes of @parent. Each child nodes are stored to @child. + * The @child can be mixture of a value node and subkey nodes. */ #define xbc_node_for_each_child(parent, child) \ for (child = xbc_node_get_child(parent); child != NULL ; \ child = xbc_node_get_next(child)) +/** + * xbc_node_for_each_subkey() - Iterate child subkey nodes + * @parent: An XBC node. + * @child: Iterated XBC node. + * + * Iterate subkey nodes of @parent. Each child nodes are stored to @child. + * The @child is only the subkey node. + */ +#define xbc_node_for_each_subkey(parent, child) \ + for (child = xbc_node_get_subkey(parent); child != NULL ; \ + child = xbc_node_get_next(child)) + /** * xbc_node_for_each_array_value() - Iterate array entries of geven key * @node: An XBC node. -- cgit v1.2.3-71-gd317