1 /* pte.h 1.3 86/01/17 */ 2 3 /* 4 * Tahoe page table entry 5 * 6 * There are two major kinds of pte's: those which have ever existed (and are 7 * thus either now in core or on the swap device), and those which have 8 * never existed, but which will be filled on demand at first reference. 9 * There is a structure describing each. There is also an ancillary 10 * structure used in page clustering. 11 */ 12 13 #ifndef LOCORE 14 struct pte 15 { 16 unsigned int 17 pg_v:1, /* valid bit */ 18 pg_prot:4, /* access control */ 19 pg_fod:1, /* is fill on demand (=0) */ 20 :1, /* must write back to swap (unused) */ 21 pg_nc:1, /* 'uncacheable page' bit */ 22 pg_m:1, /* hardware maintained modified bit */ 23 pg_u:1, /* hardware maintained 'used' bit */ 24 pg_pfnum:22; /* core page frame number or 0 */ 25 }; 26 struct hpte 27 { 28 unsigned int 29 pg_high:10, /* special for clustering */ 30 pg_pfnum:22; 31 }; 32 struct fpte 33 { 34 unsigned int 35 pg_v:1, 36 pg_prot:4, 37 pg_fod:1, /* is fill on demand (=1) */ 38 :1, 39 pg_fileno:1, /* file mapped from or TEXT or ZERO */ 40 pg_blkno:24; /* file system block number */ 41 }; 42 #endif 43 44 #define PG_V 0x80000000 45 #define PG_PROT 0x78000000 /* all protection bits (dorit). */ 46 #define PG_FOD 0x04000000 47 #define PG_SWAPM 0x02000000 48 #define PG_N 0x01000000 /* Non-cacheable */ 49 #define PG_M 0x00800000 50 #define PG_U 0x00400000 /* not currently used */ 51 #define PG_PFNUM 0x003fffff 52 53 #define PG_FZERO 0 54 #define PG_FTEXT 1 55 #define PG_FMAX (PG_FTEXT) 56 57 #define PG_NOACC 0 58 #define PG_KR 0x40000000 59 #define PG_KW 0x60000000 60 #define PG_URKR 0x50000000 61 #define PG_URKW 0x70000000 62 #define PG_UW 0x78000000 63 64 /* 65 * Pte related macros 66 */ 67 #define dirty(pte) ((pte)->pg_fod == 0 && (pte)->pg_pfnum && (pte)->pg_m) 68 69 #ifndef LOCORE 70 #ifdef KERNEL 71 /* utilities defined in locore.s */ 72 extern struct pte Sysmap[]; 73 extern struct pte Usrptmap[]; 74 extern struct pte usrpt[]; 75 extern struct pte Swapmap[]; 76 extern struct pte Forkmap[]; 77 extern struct pte Xswapmap[]; 78 extern struct pte Xswap2map[]; 79 extern struct pte Pushmap[]; 80 extern struct pte Vfmap[]; 81 extern struct pte mmap[]; 82 extern struct pte msgbufmap[]; 83 extern struct pte camap[]; 84 #endif 85 #endif 86