From 7559923b1ab447db0539e51e3f6efbb325ab6760 Mon Sep 17 00:00:00 2001
From: Masami Hiramatsu <mhiramat@kernel.org>
Date: Wed, 2 Jun 2021 17:18:58 +0900
Subject: [PATCH] FROMLIST: bootconfig: Change array value to use child node

It is not possible to put an array value with subkeys under
a key node, because both of subkeys and the array elements
are using "next" field of the xbc_node.

Thus this changes the array values to use "child" field in
the array case. The reason why split this change is to
test it easily.

Picking this up FROMLIST to get the fix ASAP. It is likely to be
accepted upstream.

Signed-off-by: Devin Moore <devinmoore@google.com>
Link: https://lore.kernel.org/lkml/162262192121.264090.6540508908529705156.stgit@devnote2/
Bug: 183237066
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Change-Id: Iabd54cda32f6bde12297942d6b03bd2555e6eb0c
---
 fs/proc/bootconfig.c       |  2 +-
 include/linux/bootconfig.h |  6 +++---
 lib/bootconfig.c           | 23 +++++++++++++++++++----
 tools/bootconfig/main.c    |  2 +-
 4 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/fs/proc/bootconfig.c b/fs/proc/bootconfig.c
index ad31ec4ad627..6d8d4bf20837 100644
--- a/fs/proc/bootconfig.c
+++ b/fs/proc/bootconfig.c
@@ -49,7 +49,7 @@ static int __init copy_xbc_key_value_list(char *dst, size_t size)
 				else
 					q = '"';
 				ret = snprintf(dst, rest(dst, end), "%c%s%c%s",
-					q, val, q, vnode->next ? ", " : "\n");
+					q, val, q, xbc_node_is_array(vnode) ? ", " : "\n");
 				if (ret < 0)
 					goto out;
 				dst += ret;
diff --git a/include/linux/bootconfig.h b/include/linux/bootconfig.h
index 2696eb0fc149..3178a31fdabc 100644
--- a/include/linux/bootconfig.h
+++ b/include/linux/bootconfig.h
@@ -71,7 +71,7 @@ static inline __init bool xbc_node_is_key(struct xbc_node *node)
  */
 static inline __init bool xbc_node_is_array(struct xbc_node *node)
 {
-	return xbc_node_is_value(node) && node->next != 0;
+	return xbc_node_is_value(node) && node->child != 0;
 }
 
 /**
@@ -140,7 +140,7 @@ static inline struct xbc_node * __init xbc_find_node(const char *key)
  */
 #define xbc_array_for_each_value(anode, value)				\
 	for (value = xbc_node_get_data(anode); anode != NULL ;		\
-	     anode = xbc_node_get_next(anode),				\
+	     anode = xbc_node_get_child(anode),				\
 	     value = anode ? xbc_node_get_data(anode) : NULL)
 
 /**
@@ -171,7 +171,7 @@ static inline struct xbc_node * __init xbc_find_node(const char *key)
  */
 #define xbc_node_for_each_array_value(node, key, anode, value)		\
 	for (value = xbc_node_find_value(node, key, &anode); value != NULL; \
-	     anode = xbc_node_get_next(anode),				\
+	     anode = xbc_node_get_child(anode),				\
 	     value = anode ? xbc_node_get_data(anode) : NULL)
 
 /**
diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index 649ed44f199c..2974e299cb7a 100644
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -367,6 +367,14 @@ static inline __init struct xbc_node *xbc_last_sibling(struct xbc_node *node)
 	return node;
 }
 
+static inline __init struct xbc_node *xbc_last_child(struct xbc_node *node)
+{
+	while (node->child)
+		node = xbc_node_get_child(node);
+
+	return node;
+}
+
 static struct xbc_node * __init xbc_add_sibling(char *data, u32 flag)
 {
 	struct xbc_node *sib, *node = xbc_add_node(data, flag);
@@ -517,17 +525,20 @@ static int __init xbc_parse_array(char **__v)
 	char *next;
 	int c = 0;
 
+	if (last_parent->child)
+		last_parent = xbc_node_get_child(last_parent);
+
 	do {
 		c = __xbc_parse_value(__v, &next);
 		if (c < 0)
 			return c;
 
-		node = xbc_add_sibling(*__v, XBC_VALUE);
+		node = xbc_add_child(*__v, XBC_VALUE);
 		if (!node)
 			return -ENOMEM;
 		*__v = next;
 	} while (c == ',');
-	node->next = 0;
+	node->child = 0;
 
 	return c;
 }
@@ -615,8 +626,12 @@ static int __init xbc_parse_kv(char **k, char *v, int op)
 
 	if (op == ':' && child) {
 		xbc_init_node(child, v, XBC_VALUE);
-	} else if (!xbc_add_sibling(v, XBC_VALUE))
-		return -ENOMEM;
+	} else {
+		if (op == '+' && child)
+			last_parent = xbc_last_child(child);
+		if (!xbc_add_sibling(v, XBC_VALUE))
+			return -ENOMEM;
+	}
 
 	if (c == ',') {	/* Array */
 		c = xbc_parse_array(&next);
diff --git a/tools/bootconfig/main.c b/tools/bootconfig/main.c
index 7362bef1a368..7a98756e594a 100644
--- a/tools/bootconfig/main.c
+++ b/tools/bootconfig/main.c
@@ -27,7 +27,7 @@ static int xbc_show_value(struct xbc_node *node, bool semicolon)
 			q = '\'';
 		else
 			q = '"';
-		printf("%c%s%c%s", q, val, q, node->next ? ", " : eol);
+		printf("%c%s%c%s", q, val, q, xbc_node_is_array(node) ? ", " : eol);
 		i++;
 	}
 	return i;