1 /* 2 * Copyright (c) 1991 Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * the Systems Programming Group of the University of Utah Computer 7 * Science Department and William Jolitz of UUNET Technologies Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * from: @(#)pmap.h 7.4 (Berkeley) 5/12/91 38 * $Id: pmap.h,v 1.3 1993/07/29 21:42:21 jtc Exp $ 39 */ 40 41 /* 42 * Derived from hp300 version by Mike Hibler, this version by William 43 * Jolitz uses a recursive map [a pde points to the page directory] to 44 * map the page tables using the pagetables themselves. This is done to 45 * reduce the impact on kernel virtual memory for lots of sparse address 46 * space, and to reduce the cost of memory to each process. 47 * 48 * from hp300: @(#)pmap.h 7.2 (Berkeley) 12/16/90 49 */ 50 51 #ifndef _PMAP_MACHINE_ 52 #define _PMAP_MACHINE_ 1 53 54 /* 55 * 386 page table entry and page table directory 56 * W.Jolitz, 8/89 57 */ 58 59 struct pde 60 { 61 unsigned int 62 pd_v:1, /* valid bit */ 63 pd_prot:2, /* access control */ 64 pd_mbz1:2, /* reserved, must be zero */ 65 pd_u:1, /* hardware maintained 'used' bit */ 66 :1, /* not used */ 67 pd_mbz2:2, /* reserved, must be zero */ 68 :3, /* reserved for software */ 69 pd_pfnum:20; /* physical page frame number of pte's*/ 70 }; 71 72 #define PD_MASK 0xffc00000 /* page directory address bits */ 73 #define PT_MASK 0x003ff000 /* page table address bits */ 74 #define PD_SHIFT 22 /* page directory address shift */ 75 #define PG_SHIFT 12 /* page table address shift */ 76 77 struct pte 78 { 79 unsigned int 80 pg_v:1, /* valid bit */ 81 pg_prot:2, /* access control */ 82 pg_mbz1:2, /* reserved, must be zero */ 83 pg_u:1, /* hardware maintained 'used' bit */ 84 pg_m:1, /* hardware maintained modified bit */ 85 pg_mbz2:2, /* reserved, must be zero */ 86 pg_w:1, /* software, wired down page */ 87 :1, /* software (unused) */ 88 pg_nc:1, /* 'uncacheable page' bit */ 89 pg_pfnum:20; /* physical page frame number */ 90 }; 91 92 #define PG_V 0x00000001 93 #define PG_RO 0x00000000 94 #define PG_RW 0x00000002 95 #define PG_u 0x00000004 96 #define PG_PROT 0x00000006 /* all protection bits . */ 97 #define PG_W 0x00000200 98 #define PG_N 0x00000800 /* Non-cacheable */ 99 #define PG_M 0x00000040 100 #define PG_U 0x00000020 101 #define PG_FRAME 0xfffff000 102 103 #define PG_NOACC 0 104 #define PG_KR 0x00000000 105 #define PG_KW 0x00000002 106 #define PG_URKR 0x00000004 107 #define PG_URKW 0x00000004 108 #define PG_UW 0x00000006 109 110 /* Garbage for current bastardized pager that assumes a hp300 */ 111 #define PG_NV 0 112 #define PG_CI 0 113 /* 114 * Page Protection Exception bits 115 */ 116 117 #define PGEX_P 0x01 /* Protection violation vs. not present */ 118 #define PGEX_W 0x02 /* during a Write cycle */ 119 #define PGEX_U 0x04 /* access from User mode (UPL) */ 120 121 typedef struct pde pd_entry_t; /* page directory entry */ 122 typedef struct pte pt_entry_t; /* Mach page table entry */ 123 124 /* 125 * One page directory, shared between 126 * kernel and user modes. 127 */ 128 #define I386_PAGE_SIZE NBPG 129 #define I386_PDR_SIZE NBPDR 130 131 #define I386_KPDES 8 /* KPT page directory size */ 132 #define I386_UPDES NBPDR/sizeof(struct pde)-8 /* UPT page directory size */ 133 134 #define UPTDI 0x3f6 /* ptd entry for u./kernel&user stack */ 135 #define PTDPTDI 0x3f7 /* ptd entry that points to ptd! */ 136 #define KPTDI_FIRST 0x3f8 /* start of kernel virtual pde's */ 137 #define KPTDI_LAST 0x3fA /* last of kernel virtual pde's */ 138 139 /* 140 * Address of current and alternate address space page table maps 141 * and directories. 142 */ 143 #ifdef KERNEL 144 extern struct pte PTmap[], APTmap[], Upte; 145 extern struct pde PTD[], APTD[], PTDpde, APTDpde, Upde; 146 extern pt_entry_t *Sysmap; 147 148 extern int IdlePTD; /* physical address of "Idle" state directory */ 149 #endif 150 151 /* 152 * virtual address to page table entry and 153 * to physical address. Likewise for alternate address space. 154 * Note: these work recursively, thus vtopte of a pte will give 155 * the corresponding pde that in turn maps it. 156 */ 157 #define vtopte(va) (PTmap + i386_btop(va)) 158 #define kvtopte(va) vtopte(va) 159 #define ptetov(pt) (i386_ptob(pt - PTmap)) 160 #define vtophys(va) (i386_ptob(vtopte(va)->pg_pfnum) | ((int)(va) & PGOFSET)) 161 #define ispt(va) ((va) >= UPT_MIN_ADDRESS && (va) <= KPT_MAX_ADDRESS) 162 163 #define avtopte(va) (APTmap + i386_btop(va)) 164 #define ptetoav(pt) (i386_ptob(pt - APTmap)) 165 #define avtophys(va) (i386_ptob(avtopte(va)->pg_pfnum) | ((int)(va) & PGOFSET)) 166 167 /* 168 * macros to generate page directory/table indicies 169 */ 170 171 #define pdei(va) (((va)&PD_MASK)>>PD_SHIFT) 172 #define ptei(va) (((va)&PT_MASK)>>PG_SHIFT) 173 174 /* 175 * Pmap stuff 176 */ 177 178 struct pmap { 179 pd_entry_t *pm_pdir; /* KVA of page directory */ 180 boolean_t pm_pdchanged; /* pdir changed */ 181 short pm_dref; /* page directory ref count */ 182 short pm_count; /* pmap reference count */ 183 simple_lock_data_t pm_lock; /* lock on pmap */ 184 struct pmap_statistics pm_stats; /* pmap statistics */ 185 long pm_ptpages; /* more stats: PT pages */ 186 }; 187 188 typedef struct pmap *pmap_t; 189 190 #ifdef KERNEL 191 extern pmap_t kernel_pmap; 192 #endif 193 194 /* 195 * Macros for speed 196 */ 197 #define PMAP_ACTIVATE(pmapp, pcbp) \ 198 if ((pmapp) != NULL /*&& (pmapp)->pm_pdchanged */) { \ 199 (pcbp)->pcb_cr3 = \ 200 pmap_extract(kernel_pmap, (pmapp)->pm_pdir); \ 201 if ((pmapp) == &curproc->p_vmspace->vm_pmap) \ 202 load_cr3((pcbp)->pcb_cr3); \ 203 (pmapp)->pm_pdchanged = FALSE; \ 204 } 205 206 #define PMAP_DEACTIVATE(pmapp, pcbp) 207 208 /* 209 * For each vm_page_t, there is a list of all currently valid virtual 210 * mappings of that page. An entry is a pv_entry_t, the list is pv_table. 211 */ 212 typedef struct pv_entry { 213 struct pv_entry *pv_next; /* next pv_entry */ 214 pmap_t pv_pmap; /* pmap where mapping lies */ 215 vm_offset_t pv_va; /* virtual address for mapping */ 216 int pv_flags; /* flags */ 217 } *pv_entry_t; 218 219 #define PV_ENTRY_NULL ((pv_entry_t) 0) 220 221 #define PV_CI 0x01 /* all entries must be cache inhibited */ 222 #define PV_PTPAGE 0x02 /* entry maps a page table page */ 223 224 #ifdef KERNEL 225 226 pv_entry_t pv_table; /* array of entries, one per page */ 227 228 #define pa_index(pa) atop(pa - vm_first_phys) 229 #define pa_to_pvh(pa) (&pv_table[pa_index(pa)]) 230 231 #define pmap_resident_count(pmap) ((pmap)->pm_stats.resident_count) 232 233 #endif /* KERNEL */ 234 235 #endif /* _PMAP_MACHINE_ */ 236