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| author | Frans Kaashoek <kaashoek@mit.edu> | 2018-10-02 08:50:05 -0400 |
|---|---|---|
| committer | Frans Kaashoek <kaashoek@mit.edu> | 2018-10-02 08:50:05 -0400 |
| commit | ec110149ed7a9439e73724097ab78110c5661e08 (patch) | |
| tree | 2747de1b963bb9bdcc4d5e1d21f3ebdd6c05037c | |
| parent | a0389f707fd8f106c0c0527603e1f55ed21bfa4f (diff) | |
| download | xv6-labs-ec110149ed7a9439e73724097ab78110c5661e08.tar.gz xv6-labs-ec110149ed7a9439e73724097ab78110c5661e08.tar.bz2 xv6-labs-ec110149ed7a9439e73724097ab78110c5661e08.zip | |
simplify layout pic
| -rw-r--r-- | mmu.h | 6 |
1 files changed, 3 insertions, 3 deletions
@@ -89,15 +89,15 @@ struct segdesc { // | Sign | PML4 |Page Directory| Page Dir |Page Table | Offset Page | // |Extend| Index | Pointer Index| Index | Index | in Page | // +------+-------+--------------+----------+------------+-------------+ -// \-PMX(va)-/\-PDPX(va)--/ \-PDX(va)-/ \-PTX(va)-/ +// L3 pgtab L2 pgtab L1 pgtab L0 pgtab // Page directory and page table constants. -#define NPDENTRIES 512 // # directory entries per page directory +#define NPDENTRIES 512 // # directory entries per page directory #define PGSIZE 4096 // bytes mapped by a page #define PGSHIFT 12 // offset of PTX in a linear address #define PXMASK 0x1FF -#define PXSHIFT(n) (PGSHIFT+(9*(n))) +#define PXSHIFT(n) (PGSHIFT+(9*(n))) // shift for index into level n page table #define PX(n, va) ((((uint64) (va)) >> PXSHIFT(n)) & PXMASK) #define L_PML4 3 |