Linux内核基础篇——container

/**
 * container_of - cast a member of a structure out to the containing structure
 * @ptr:    the pointer to the member.
 * @type:   the type of the container struct this is embedded in.
 * @member: the name of the member within the struct.
 *
 */
#define container_of(ptr, type, member) ({          \\
    const typeof( ((type *)0)->member ) *__mptr = (ptr); \\
    (type *)( (char *)__mptr - offsetof(type,member) );})