TW_CPU_TO_SGL
#define TW_CPU_TO_SGL(x) cpu_to_le64(x)
#define TW_CPU_TO_SGL(x) cpu_to_le32(x)
#define TW_CPU_TO_SGL(x) (sizeof(dma_addr_t) > 4 ? cpu_to_le64(x) : cpu_to_le32(x))