1 /* 2 * Copyright (c) 1987 Carnegie-Mellon University 3 * Copyright (c) 1991 Regents of the University of California. 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * The Mach Operating System project at Carnegie-Mellon University. 8 * 9 * The CMU software License Agreement specifies the terms and conditions 10 * for use and redistribution. 11 * 12 * This version by William Jolitz for UUNET Technologies, Inc. 13 * 14 * Derived from hp300 version by Mike Hibler, this version by William 15 * Jolitz uses a recursive map [a pde points to the page directory] to 16 * map the page tables using the pagetables themselves. This is done to 17 * reduce the impact on kernel virtual memory for lots of sparse address 18 * space, and to reduce the cost of memory to each process. 19 * 20 * from hp300: @(#)pmap.h 7.2 (Berkeley) 12/16/90 21 * 22 * @(#)pmap.h 1.4 (Berkeley) 04/17/91 23 */ 24 25 #ifndef _PMAP_MACHINE_ 26 #define _PMAP_MACHINE_ 1 27 28 #include "sys/lock.h" 29 #include "machine/vmparam.h" 30 #include "vm/vm_statistics.h" 31 32 /* 33 * 386 page table entry and page table directory 34 * W.Jolitz, 8/89 35 */ 36 37 struct pde 38 { 39 unsigned int 40 pd_v:1, /* valid bit */ 41 pd_prot:2, /* access control */ 42 pd_mbz1:2, /* reserved, must be zero */ 43 pd_u:1, /* hardware maintained 'used' bit */ 44 :1, /* not used */ 45 pd_mbz2:2, /* reserved, must be zero */ 46 :3, /* reserved for software */ 47 pd_pfnum:20; /* physical page frame number of pte's*/ 48 }; 49 50 #define PD_MASK 0xffc00000 /* page directory address bits */ 51 #define PT_MASK 0x003ff000 /* page table address bits */ 52 #define PD_SHIFT 22 /* page directory address shift */ 53 #define PG_SHIFT 12 /* page table address shift */ 54 55 struct pte 56 { 57 unsigned int 58 pg_v:1, /* valid bit */ 59 pg_prot:2, /* access control */ 60 pg_mbz1:2, /* reserved, must be zero */ 61 pg_u:1, /* hardware maintained 'used' bit */ 62 pg_m:1, /* hardware maintained modified bit */ 63 pg_mbz2:2, /* reserved, must be zero */ 64 pg_w:1, /* software, wired down page */ 65 :1, /* software (unused) */ 66 pg_nc:1, /* 'uncacheable page' bit */ 67 pg_pfnum:20; /* physical page frame number */ 68 }; 69 70 #define PG_V 0x00000001 71 #define PG_RO 0x00000000 72 #define PG_RW 0x00000002 73 #define PG_u 0x00000004 74 #define PG_PROT 0x00000006 /* all protection bits . */ 75 #define PG_W 0x00000200 76 #define PG_N 0x00000800 /* Non-cacheable */ 77 #define PG_M 0x00000040 78 #define PG_U 0x00000020 79 #define PG_FRAME 0xfffff000 80 81 #define PG_NOACC 0 82 #define PG_KR 0x00000000 83 #define PG_KW 0x00000002 84 #define PG_URKR 0x00000004 85 #define PG_URKW 0x00000004 86 #define PG_UW 0x00000006 87 88 /* Garbage for current bastardized pager that assumes a hp300 */ 89 #define PG_NV 0 90 #define PG_CI 0 91 /* 92 * Page Protection Exception bits 93 */ 94 95 #define PGEX_P 0x01 /* Protection violation vs. not present */ 96 #define PGEX_W 0x02 /* during a Write cycle */ 97 #define PGEX_U 0x04 /* access from User mode (UPL) */ 98 99 typedef struct pde pd_entry_t; /* page directory entry */ 100 typedef struct pte pt_entry_t; /* Mach page table entry */ 101 102 #define PD_ENTRY_NULL ((pd_entry_t *) 0) 103 #define PT_ENTRY_NULL ((pt_entry_t *) 0) 104 105 /* 106 * One page directory, shared between 107 * kernel and user modes. 108 */ 109 #define I386_PAGE_SIZE NBPG 110 #define I386_PDR_SIZE NBPDR 111 112 #define I386_KPDES 8 /* KPT page directory size */ 113 #define I386_UPDES NBPDR/sizeof(struct pde)-8 /* UPT page directory size */ 114 115 #define UPTDI 0x3f6 /* ptd entry for u./kernel&user stack */ 116 #define PTDPTDI 0x3f7 /* ptd entry that points to ptd! */ 117 #define KPTDI_FIRST 0x3f8 /* start of kernel virtual pde's */ 118 #define KPTDI_LAST 0x3fA /* last of kernel virtual pde's */ 119 120 extern pt_entry_t *Sysmap; 121 122 /* 123 * Address of current and alternate address space page table maps 124 * and directories. 125 */ 126 extern struct pte PTmap[], APTmap[], Upte; 127 extern struct pde PTD[], APTD[], PTDpde, APTDpde, Upde; 128 129 extern int IdlePTD; 130 131 /* 132 * virtual address to page table entry and 133 * to physical address. Likewise for alternate address space. 134 * Note: these work recursively, thus vtopte of a pte will give 135 * the corresponding pde that in turn maps it. 136 */ 137 #define vtopte(va) (PTmap + i386_btop(va)) 138 #define kvtopte(va) vtopte(va) 139 #define ptetov(pt) (i386_ptob(pt - PTmap)) 140 #define vtophys(va) (i386_ptob(vtopte(va)->pg_pfnum) | ((int)(va) & PGOFSET)) 141 #define ispt(va) ((va) >= UPT_MIN_ADDRESS && (va) <= KPT_MAX_ADDRESS) 142 143 #define avtopte(va) (APTmap + i386_btop(va)) 144 #define ptetoav(pt) (i386_ptob(pt - APTmap)) 145 #define avtophys(va) (i386_ptob(avtopte(va)->pg_pfnum) | ((int)(va) & PGOFSET)) 146 147 /* 148 * macros to generate page directory/table indicies 149 */ 150 151 #define pdei(va) (((va)&PD_MASK)>>PD_SHIFT) 152 #define ptei(va) (((va)&PT_MASK)>>PT_SHIFT) 153 154 /* 155 * Pmap stuff 156 */ 157 #define PMAP_NULL ((pmap_t) 0) 158 159 struct pmap { 160 pd_entry_t *pm_pdir; /* KVA of page directory */ 161 /* caddr_t *pm_ptobj; /* page table object */ 162 boolean_t pm_pdchanged; /* pdir changed */ 163 short pm_dref; /* page directory ref count */ 164 short pm_count; /* pmap reference count */ 165 simple_lock_data_t pm_lock; /* lock on pmap */ 166 struct pmap_statistics pm_stats; /* pmap statistics */ 167 long pm_ptpages; /* more stats: PT pages */ 168 }; 169 170 typedef struct pmap *pmap_t; 171 172 extern pmap_t kernel_pmap; 173 174 /* 175 * Macros for speed 176 */ 177 #define PMAP_ACTIVATE(pmapp, pcbp) \ 178 if ((pmapp) != PMAP_NULL /*&& (pmapp)->pm_pdchanged */) { \ 179 (pcbp)->pcb_cr3 = \ 180 pmap_extract(kernel_pmap, (pmapp)->pm_pdir); \ 181 if ((pmapp) == u.u_procp->p_map->pmap) \ 182 load_cr3((pcbp)->pcb_cr3); \ 183 (pmapp)->pm_pdchanged = FALSE; \ 184 } 185 186 #define PMAP_DEACTIVATE(pmapp, pcbp) 187 188 /* 189 * For each vm_page_t, there is a list of all currently valid virtual 190 * mappings of that page. An entry is a pv_entry_t, the list is pv_table. 191 */ 192 typedef struct pv_entry { 193 struct pv_entry *pv_next; /* next pv_entry */ 194 pmap_t pv_pmap; /* pmap where mapping lies */ 195 vm_offset_t pv_va; /* virtual address for mapping */ 196 int pv_flags; /* flags */ 197 } *pv_entry_t; 198 199 #define PV_ENTRY_NULL ((pv_entry_t) 0) 200 201 #define PV_CI 0x01 /* all entries must be cache inhibited */ 202 #define PV_PTPAGE 0x02 /* entry maps a page table page */ 203 204 #ifdef KERNEL 205 206 pv_entry_t pv_table; /* array of entries, one per page */ 207 208 #define pa_index(pa) atop(pa - vm_first_phys) 209 #define pa_to_pvh(pa) (&pv_table[pa_index(pa)]) 210 211 #define pmap_resident_count(pmap) ((pmap)->pm_stats.resident_count) 212 213 #endif KERNEL 214 215 #endif _PMAP_MACHINE_ 216