2 * lru lists are circular with a list head
3 * pointing to the start and end of the list
9 * Create an lru chain of buffers
14 h->lprev = h->lnext = h;
18 * Add a member to an lru chain
21 lruadd(Lru *h, Lru *m)
30 * Move to end of lru list
33 lruref(Lru *h, Lru *m)
36 return; /* alread at end of list */
41 m->lprev->lnext = m->lnext;
42 m->lnext->lprev = m->lprev;
54 * Move to head of lru list
57 lruderef(Lru *h, Lru *m)
60 return; /* alread at head of list */
65 m->lprev->lnext = m->lnext;
66 m->lnext->lprev = m->lprev;