list_private_prev_entry
pos = list_private_prev_entry(pos, member))
for (pos = list_private_prev_entry(pos, member); \
pos = list_private_prev_entry(pos, member))
pos = list_private_prev_entry(pos, member))
n = list_private_prev_entry(pos, member); \
pos = n, n = list_private_prev_entry(n, member))
list_private_prev_entry(pos, member))
pos = list_private_prev_entry(pos, list);