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 * Derived from hp300 version by Mike Hibler, this version by William 38 * Jolitz uses a recursive map [a pde points to the page directory] to 39 * map the page tables using the pagetables themselves. This is done to 40 * reduce the impact on kernel virtual memory for lots of sparse address 41 * space, and to reduce the cost of memory to each process. 42 * 43 * from: hp300: @(#)pmap.h 7.2 (Berkeley) 12/16/90 44 * from: @(#)pmap.h 7.4 (Berkeley) 5/12/91 45 * $Id: pmap.h,v 1.19 1994/12/18 03:11:46 davidg Exp $ 46 */ 47 48 #ifndef _MACHINE_PMAP_H_ 49 #define _MACHINE_PMAP_H_ 50 51 #include <machine/pte.h> 52 53 typedef unsigned int *pd_entry_t; 54 typedef unsigned int *pt_entry_t; 55 56 /* 57 * NKPDE controls the virtual space of the kernel, what ever is left, minus 58 * the alternate page table area is given to the user (NUPDE) 59 */ 60 /* 61 * NKPDE controls the virtual space of the kernel, what ever is left is 62 * given to the user (NUPDE) 63 */ 64 #ifndef NKPT 65 #if 0 66 #define NKPT 26 /* actual number of kernel page tables */ 67 #else 68 #define NKPT 9 /* actual number of kernel page tables */ 69 #endif 70 #endif 71 #ifndef NKPDE 72 #define NKPDE 63 /* addressable number of page tables/pde's */ 73 #endif 74 75 #define NUPDE (NPTEPG-NKPDE) /* number of user pde's */ 76 77 /* 78 * The *PTDI values control the layout of virtual memory 79 * 80 * XXX This works for now, but I am not real happy with it, I'll fix it 81 * right after I fix locore.s and the magic 28K hole 82 */ 83 #define APTDPTDI (NPTEPG-1) /* alt ptd entry that points to APTD */ 84 #define KPTDI (APTDPTDI-NKPDE)/* start of kernel virtual pde's */ 85 #define PTDPTDI (KPTDI-1) /* ptd entry that points to ptd! */ 86 #define KSTKPTDI (PTDPTDI-1) /* ptd entry for u./kernel&user stack */ 87 #define KSTKPTEOFF (NBPG/sizeof(pd_entry_t)-UPAGES) /* pte entry for kernel stack */ 88 89 #define PDESIZE sizeof(pd_entry_t) /* for assembly files */ 90 #define PTESIZE sizeof(pt_entry_t) /* for assembly files */ 91 92 /* 93 * Address of current and alternate address space page table maps 94 * and directories. 95 */ 96 #ifdef KERNEL 97 extern pt_entry_t PTmap[], APTmap[], Upte; 98 extern pd_entry_t PTD[], APTD[], PTDpde, APTDpde, Upde; 99 100 extern int IdlePTD; /* physical address of "Idle" state directory */ 101 #endif 102 103 /* 104 * virtual address to page table entry and 105 * to physical address. Likewise for alternate address space. 106 * Note: these work recursively, thus vtopte of a pte will give 107 * the corresponding pde that in turn maps it. 108 */ 109 #define vtopte(va) (PTmap + i386_btop(va)) 110 #define kvtopte(va) vtopte(va) 111 #define ptetov(pt) (i386_ptob(pt - PTmap)) 112 #define vtophys(va) (((int) (*vtopte(va))&PG_FRAME) | ((int)(va) & PGOFSET)) 113 #define ispt(va) ((va) >= UPT_MIN_ADDRESS && (va) <= KPT_MAX_ADDRESS) 114 115 #define avtopte(va) (APTmap + i386_btop(va)) 116 #define ptetoav(pt) (i386_ptob(pt - APTmap)) 117 #define avtophys(va) (((int) (*avtopte(va))&PG_FRAME) | ((int)(va) & PGOFSET)) 118 119 #ifdef KERNEL 120 /* 121 * Routine: pmap_kextract 122 * Function: 123 * Extract the physical page address associated 124 * kernel virtual address. 125 */ 126 static __inline vm_offset_t 127 pmap_kextract(vm_offset_t va) 128 { 129 vm_offset_t pa = *(int *)vtopte(va); 130 pa = (pa & PG_FRAME) | (va & ~PG_FRAME); 131 return pa; 132 } 133 134 /* 135 * pmap_is_referenced: 136 * 137 * Return whether or not the specified physical page was referenced 138 * by any physical maps. 139 */ 140 #define pmap_is_referenced(pa) pmap_testbit((pa), PG_U) 141 142 /* 143 * pmap_is_modified: 144 * 145 * Return whether or not the specified physical page was modified 146 * in any physical maps. 147 */ 148 #define pmap_is_modified(pa) pmap_testbit((pa), PG_M) 149 150 /* 151 * Clear the modify bits on the specified physical page. 152 */ 153 #define pmap_clear_modify(pa) pmap_changebit((pa), PG_M, FALSE) 154 155 /* 156 * pmap_clear_reference: 157 * 158 * Clear the reference bit on the specified physical page. 159 */ 160 #define pmap_clear_reference(pa) pmap_changebit((pa), PG_U, FALSE) 161 162 /* 163 * Routine: pmap_copy_on_write 164 * Function: 165 * Remove write privileges from all 166 * physical maps for this physical page. 167 */ 168 #define pmap_copy_on_write(pa) pmap_changebit((pa), PG_RW, FALSE) 169 170 #endif 171 172 /* 173 * macros to generate page directory/table indicies 174 */ 175 176 #define pdei(va) (((va)&PD_MASK)>>PD_SHIFT) 177 #define ptei(va) (((va)&PT_MASK)>>PG_SHIFT) 178 179 /* 180 * Pmap stuff 181 */ 182 183 struct pmap { 184 pd_entry_t *pm_pdir; /* KVA of page directory */ 185 boolean_t pm_pdchanged; /* pdir changed */ 186 short pm_dref; /* page directory ref count */ 187 short pm_count; /* pmap reference count */ 188 simple_lock_data_t pm_lock; /* lock on pmap */ 189 struct pmap_statistics pm_stats; /* pmap statistics */ 190 long pm_ptpages; /* more stats: PT pages */ 191 }; 192 193 typedef struct pmap *pmap_t; 194 195 #ifdef KERNEL 196 extern pmap_t kernel_pmap; 197 #endif 198 199 /* 200 * Macros for speed 201 */ 202 #define PMAP_ACTIVATE(pmapp, pcbp) \ 203 if ((pmapp) != NULL /*&& (pmapp)->pm_pdchanged */) { \ 204 (pcbp)->pcb_cr3 = \ 205 pmap_extract(kernel_pmap, (vm_offset_t)(pmapp)->pm_pdir); \ 206 if ((pmapp) == &curproc->p_vmspace->vm_pmap) \ 207 load_cr3((pcbp)->pcb_cr3); \ 208 (pmapp)->pm_pdchanged = FALSE; \ 209 } 210 211 #define PMAP_DEACTIVATE(pmapp, pcbp) 212 213 /* 214 * For each vm_page_t, there is a list of all currently valid virtual 215 * mappings of that page. An entry is a pv_entry_t, the list is pv_table. 216 */ 217 typedef struct pv_entry { 218 struct pv_entry *pv_next; /* next pv_entry */ 219 pmap_t pv_pmap; /* pmap where mapping lies */ 220 vm_offset_t pv_va; /* virtual address for mapping */ 221 } *pv_entry_t; 222 223 #define PV_ENTRY_NULL ((pv_entry_t) 0) 224 225 #define PV_CI 0x01 /* all entries must be cache inhibited */ 226 #define PV_PTPAGE 0x02 /* entry maps a page table page */ 227 228 #ifdef KERNEL 229 230 pv_entry_t pv_table; /* array of entries, one per page */ 231 232 #define pa_index(pa) atop(pa - vm_first_phys) 233 #define pa_to_pvh(pa) (&pv_table[pa_index(pa)]) 234 235 #define pmap_resident_count(pmap) ((pmap)->pm_stats.resident_count) 236 237 struct pcb; 238 239 void pmap_activate __P((pmap_t, struct pcb *)); 240 void pmap_changebit __P((vm_offset_t, int, boolean_t)); 241 pmap_t pmap_kernel __P((void)); 242 boolean_t pmap_page_exists __P((pmap_t, vm_offset_t)); 243 pt_entry_t *pmap_pte(pmap_t, vm_offset_t); 244 vm_page_t pmap_pte_vm_page __P((pmap_t, vm_offset_t)); 245 246 #endif /* KERNEL */ 247 248 #endif /* !_MACHINE_PMAP_H_ */ 249