scripts: import more hash table macros

Add more macros used for removing hash table entries.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

1 files changed, 50 insertions, 0 deletions

diff --git a/scripts/include/hashtable.h b/scripts/include/hashtable.h
index a0a2c8f5f639..45abcb12bfce 100644
--- a/scripts/include/hashtable.h
+++ b/scripts/include/hashtable.h
@@ -15,6 +15,23 @@
 
 #define hash_head(table, key)		(&(table)[(key) % HASH_SIZE(table)])
 
+static inline void __hash_init(struct hlist_head *ht, unsigned int sz)
+{
+	unsigned int i;
+
+	for (i = 0; i < sz; i++)
+		INIT_HLIST_HEAD(&ht[i]);
+}
+
+/**
+ * hash_init - initialize a hash table
+ * @table: hashtable to be initialized
+ *
+ * This has to be a macro since HASH_SIZE() will not work on pointers since
+ * it calculates the size during preprocessing.
+ */
+#define hash_init(table) __hash_init(table, HASH_SIZE(table))
+
 /**
  * hash_add - add an object to a hashtable
  * @table: hashtable to add to
@@ -25,6 +42,15 @@
 	hlist_add_head(node, hash_head(table, key))
 
 /**
+ * hash_del - remove an object from a hashtable
+ * @node: &struct hlist_node of the object to remove
+ */
+static inline void hash_del(struct hlist_node *node)
+{
+	hlist_del_init(node);
+}
+
+/**
  * hash_for_each - iterate over a hashtable
  * @table: hashtable to iterate
  * @obj: the type * to use as a loop cursor for each entry
@@ -35,6 +61,18 @@
 		hlist_for_each_entry(obj, &table[_bkt], member)
 
 /**
+ * hash_for_each_safe - iterate over a hashtable safe against removal of
+ * hash entry
+ * @table: hashtable to iterate
+ * @obj: the type * to use as a loop cursor for each entry
+ * @tmp: a &struct hlist_node used for temporary storage
+ * @member: the name of the hlist_node within the struct
+ */
+#define hash_for_each_safe(table, obj, tmp, member)			\
+	for (int _bkt = 0; _bkt < HASH_SIZE(table); _bkt++)		\
+		hlist_for_each_entry_safe(obj, tmp, &table[_bkt], member)
+
+/**
  * hash_for_each_possible - iterate over all possible objects hashing to the
  * same bucket
  * @table: hashtable to iterate
@@ -45,4 +83,16 @@
 #define hash_for_each_possible(table, obj, member, key)			\
 	hlist_for_each_entry(obj, hash_head(table, key), member)
 
+/**
+ * hash_for_each_possible_safe - iterate over all possible objects hashing to the
+ * same bucket safe against removals
+ * @table: hashtable to iterate
+ * @obj: the type * to use as a loop cursor for each entry
+ * @tmp: a &struct hlist_node used for temporary storage
+ * @member: the name of the hlist_node within the struct
+ * @key: the key of the objects to iterate over
+ */
+#define hash_for_each_possible_safe(table, obj, tmp, member, key)	\
+	hlist_for_each_entry_safe(obj, tmp, hash_head(table, key), member)
+
 #endif /* HASHTABLE_H */