1 /* $NetBSD: pmap.h,v 1.16 1994/10/31 06:30:52 andrew Exp $ */ 2 3 /* 4 * Copyright (c) 1991 Regents of the University of California. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * the Systems Programming Group of the University of Utah Computer 9 * Science Department and William Jolitz of UUNET Technologies Inc. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * @(#)pmap.h 7.4 (Berkeley) 5/12/91 40 */ 41 42 /* 43 * Derived from hp300 version by Mike Hibler, this version by William 44 * Jolitz uses a recursive map [a pde points to the page directory] to 45 * map the page tables using the pagetables themselves. This is done to 46 * reduce the impact on kernel virtual memory for lots of sparse address 47 * space, and to reduce the cost of memory to each process. 48 * 49 * from hp300: @(#)pmap.h 7.2 (Berkeley) 12/16/90 50 */ 51 52 #ifndef _I386_PMAP_H_ 53 #define _I386_PMAP_H_ 54 55 #include <machine/cpufunc.h> 56 #include <machine/pte.h> 57 58 /* 59 * 386 page table entry and page table directory 60 * W.Jolitz, 8/89 61 */ 62 63 /* 64 * One page directory, shared between 65 * kernel and user modes. 66 */ 67 #define UPTDI 0x3de /* ptd entry for u./kernel&user stack */ 68 #define PTDPTDI 0x3df /* ptd entry that points to ptd! */ 69 #define KPTDI 0x3e0 /* start of kernel virtual pde's */ 70 #define NKPDE 12 71 #define APTDPTDI 0x3ff /* start of alternate page directory */ 72 73 /* 74 * Address of current and alternate address space page table maps 75 * and directories. 76 */ 77 #ifdef KERNEL 78 extern pt_entry_t PTmap[], APTmap[], Upte; 79 extern pd_entry_t PTD[], APTD[], PTDpde, APTDpde, Upde; 80 extern pt_entry_t *Sysmap; 81 82 extern int IdlePTD; /* physical address of "Idle" state directory */ 83 84 void pmap_bootstrap __P((vm_offset_t start)); 85 boolean_t pmap_testbit __P((vm_offset_t, int)); 86 void pmap_changebit __P((vm_offset_t, int, int)); 87 __pure u_int pmap_page_index __P((vm_offset_t)); 88 #endif 89 90 /* 91 * virtual address to page table entry and 92 * to physical address. Likewise for alternate address space. 93 * Note: these work recursively, thus vtopte of a pte will give 94 * the corresponding pde that in turn maps it. 95 */ 96 #define vtopte(va) (PTmap + i386_btop(va)) 97 #define kvtopte(va) vtopte(va) 98 #define ptetov(pt) (i386_ptob(pt - PTmap)) 99 #define vtophys(va) \ 100 ((*vtopte(va) & PG_FRAME) | ((unsigned)(va) & ~PG_FRAME)) 101 102 #define avtopte(va) (APTmap + i386_btop(va)) 103 #define ptetoav(pt) (i386_ptob(pt - APTmap)) 104 #define avtophys(va) \ 105 ((*avtopte(va) & PG_FRAME) | ((unsigned)(va) & ~PG_FRAME)) 106 107 /* 108 * macros to generate page directory/table indicies 109 */ 110 #define pdei(va) (((va) & PD_MASK) >> PDSHIFT) 111 #define ptei(va) (((va) & PT_MASK) >> PGSHIFT) 112 113 /* 114 * Pmap stuff 115 */ 116 typedef struct pmap { 117 pd_entry_t *pm_pdir; /* KVA of page directory */ 118 boolean_t pm_pdchanged; /* pdir changed */ 119 short pm_dref; /* page directory ref count */ 120 short pm_count; /* pmap reference count */ 121 simple_lock_data_t pm_lock; /* lock on pmap */ 122 struct pmap_statistics pm_stats; /* pmap statistics */ 123 long pm_ptpages; /* more stats: PT pages */ 124 } *pmap_t; 125 126 /* 127 * For each vm_page_t, there is a list of all currently valid virtual 128 * mappings of that page. An entry is a pv_entry, the list is pv_table. 129 */ 130 struct pv_entry { 131 struct pv_entry *pv_next; /* next pv_entry */ 132 pmap_t pv_pmap; /* pmap where mapping lies */ 133 vm_offset_t pv_va; /* virtual address for mapping */ 134 }; 135 136 struct pv_page; 137 138 struct pv_page_info { 139 TAILQ_ENTRY(pv_page) pgi_list; 140 struct pv_entry *pgi_freelist; 141 int pgi_nfree; 142 }; 143 144 /* 145 * This is basically: 146 * ((NBPG - sizeof(struct pv_page_info)) / sizeof(struct pv_entry)) 147 */ 148 #define NPVPPG 340 149 150 struct pv_page { 151 struct pv_page_info pvp_pgi; 152 struct pv_entry pvp_pv[NPVPPG]; 153 }; 154 155 #ifdef KERNEL 156 extern struct pmap kernel_pmap_store; 157 struct pv_entry *pv_table; /* array of entries, one per page */ 158 159 #define kernel_pmap (&kernel_pmap_store) 160 #define pmap_resident_count(pmap) ((pmap)->pm_stats.resident_count) 161 #define pmap_update() tlbflush() 162 163 static __inline void 164 pmap_clear_modify(vm_offset_t pa) 165 { 166 pmap_changebit(pa, 0, ~PG_M); 167 } 168 169 static __inline void 170 pmap_clear_reference(vm_offset_t pa) 171 { 172 pmap_changebit(pa, 0, ~PG_U); 173 } 174 175 static __inline void 176 pmap_copy_on_write(vm_offset_t pa) 177 { 178 pmap_changebit(pa, PG_RO, ~PG_RW); 179 } 180 181 static __inline boolean_t 182 pmap_is_modified(vm_offset_t pa) 183 { 184 return pmap_testbit(pa, PG_M); 185 } 186 187 static __inline boolean_t 188 pmap_is_referenced(vm_offset_t pa) 189 { 190 return pmap_testbit(pa, PG_U); 191 } 192 193 static __inline vm_offset_t 194 pmap_phys_address(int ppn) 195 { 196 return i386_ptob(ppn); 197 } 198 199 #endif /* KERNEL */ 200 201 #endif /* _I386_PMAP_H_ */ 202