ref: 6ff5c10ffb06d10eee06f1d432f9cc4738496c07
dir: /sys/src/cmd/cfs/lru.h/
typedef struct Lruhead Lruhead; typedef struct Lru Lru; struct Lru { Lru *lprev; Lru *lnext; }; void lruinit(Lru*); void lruadd(Lru*, Lru*); void lruref(Lru*, Lru*); void lruderef(Lru*, Lru*);