TRB_MAX_BUFF_SIZE
#define TRB_BUFF_LEN_UP_TO_BOUNDARY(addr) (TRB_MAX_BUFF_SIZE - \
((addr) & (TRB_MAX_BUFF_SIZE - 1)))
num_trbs = DIV_ROUND_UP(len + (addr & (TRB_MAX_BUFF_SIZE - 1)),
TRB_MAX_BUFF_SIZE);
num_trbs = DIV_ROUND_UP(len + (addr & (TRB_MAX_BUFF_SIZE - 1)),
TRB_MAX_BUFF_SIZE);
#define TRB_BUFF_LEN_UP_TO_BOUNDARY(addr) (TRB_MAX_BUFF_SIZE - \
(addr & (TRB_MAX_BUFF_SIZE - 1)))