xv6

port of xv6 to x86-64
git clone http://frotz.net/git/xv6.git
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memlayout.h (1128B)


      1 // Memory layout
      2 
      3 #define EXTMEM  0x100000            // Start of extended memory
      4 #define PHYSTOP 0xE000000           // Top physical memory
      5 #define DEVSPACE 0xFE000000         // Other devices are at high addresses
      6 
      7 // Key addresses for address space layout (see kmap in vm.c for layout)
      8 #if X64
      9 #define KERNBASE 0xFFFFFFFF80000000 // First kernel virtual address
     10 #define DEVBASE  0xFFFFFFFF40000000 // First device virtual address
     11 #else
     12 #define KERNBASE 0x80000000         // First kernel virtual address
     13 #define DEVBASE  0xFE000000         // First device virtual address
     14 #endif
     15 #define KERNLINK (KERNBASE+EXTMEM)  // Address where kernel is linked
     16 
     17 #ifndef __ASSEMBLER__
     18 
     19 static inline uintp v2p(void *a) { return ((uintp) (a)) - ((uintp)KERNBASE); }
     20 static inline void *p2v(uintp a) { return (void *) ((a) + ((uintp)KERNBASE)); }
     21 
     22 #endif
     23 
     24 #define V2P(a) (((uintp) (a)) - KERNBASE)
     25 #define P2V(a) (((void *) (a)) + KERNBASE)
     26 #define IO2V(a) (((void *) (a)) + DEVBASE - DEVSPACE)
     27 
     28 #define V2P_WO(x) ((x) - KERNBASE)    // same as V2P, but without casts
     29 #define P2V_WO(x) ((x) + KERNBASE)    // same as V2P, but without casts