#define NBPG 512 #define PGOFSET (NBPG-1) /* byte offset into page */ #define PGSHIFT 9 /* LOG2(NBPG) */ #define CLSIZE 2 #define CLOFSET (CLSIZE*NBPG-1) /* for clusters, like PGOFSET */ #define BITFS(dev) ((dev) & 64) #define BSIZE(dev) (BITFS(dev)? 4096: 1024) #define BMASK(dev) (BITFS(dev)? 07777: 01777) #define BSHIFT(dev) (BITFS(dev)? 12: 10) #define PAGSIZ (NBPG*CLSIZE) #define PAGRND ((PAGSIZ)-1)