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@@ -348,6 +348,20 @@ static inline void list_splice_tail_init(struct list_head *list,
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#define list_last_entry(ptr, type, member) \
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list_entry((ptr)->prev, type, member)
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+/**
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+ * list_first_entry_or_null - get the first element from a list
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+ * @ptr: the list head to take the element from.
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+ * @type: the type of the struct this is embedded in.
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+ * @member: the name of the list_head within the struct.
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+ *
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+ * Note that if the list is empty, it returns NULL.
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+ */
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+#define list_first_entry_or_null(ptr, type, member) ({ \
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+ struct list_head *head__ = (ptr); \
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+ struct list_head *pos__ = READ_ONCE(head__->next); \
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+ pos__ != head__ ? list_entry(pos__, type, member) : NULL; \
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+})
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+
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/**
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* list_for_each - iterate over a list
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* @pos: the &struct list_head to use as a loop cursor.
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