xv6/memlayout.h
2011-08-24 10:24:40 -04:00

22 lines
844 B
C

// Memory layout
#define EXTMEM 0x100000 // Start of extended memory
#define PHYSTOP 0xE000000 // Top physical memory (too hard to get from E820)
#define DEVSPACE 0xFE000000 // Other devices are at high addresses
// Key addresses for address space layout (see kmap in vm.c for the layout)
#define KERNBASE 0xF0000000 // First kernel virtual address
#define KERNLINK (KERNBASE+EXTMEM) // Address where kernel is linked
#ifndef __ASSEMBLER__
static inline uint v2p(void *a) { return (uint) a - KERNBASE; }
static inline void *p2v(uint a) { return (void *) a + KERNBASE; }
#endif
#define V2P(a) ((uint) a - KERNBASE)
#define P2V(a) ((void *) a + KERNBASE)
#define V2P_WO(x) ((x) - KERNBASE) // same as V2P, but without casts
#define P2V_WO(x) ((x) + KERNBASE) // same as V2P, but without casts