1 /* 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * The Mach Operating System project at Carnegie-Mellon University. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * from: @(#)vm_page.h 8.2 (Berkeley) 12/13/93 37 * 38 * 39 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 40 * All rights reserved. 41 * 42 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 43 * 44 * Permission to use, copy, modify and distribute this software and 45 * its documentation is hereby granted, provided that both the copyright 46 * notice and this permission notice appear in all copies of the 47 * software, derivative works or modified versions, and any portions 48 * thereof, and that both notices appear in supporting documentation. 49 * 50 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 51 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 52 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 53 * 54 * Carnegie Mellon requests users of this software to return to 55 * 56 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 57 * School of Computer Science 58 * Carnegie Mellon University 59 * Pittsburgh PA 15213-3890 60 * 61 * any improvements or extensions that they make and grant Carnegie the 62 * rights to redistribute these changes. 63 * 64 * $Id: vm_page.h,v 1.3 1994/08/02 07:55:32 davidg Exp $ 65 */ 66 67 /* 68 * Resident memory system definitions. 69 */ 70 71 #ifndef _VM_PAGE_ 72 #define _VM_PAGE_ 73 74 /* 75 * Management of resident (logical) pages. 76 * 77 * A small structure is kept for each resident 78 * page, indexed by page number. Each structure 79 * is an element of several lists: 80 * 81 * A hash table bucket used to quickly 82 * perform object/offset lookups 83 * 84 * A list of all pages for a given object, 85 * so they can be quickly deactivated at 86 * time of deallocation. 87 * 88 * An ordered list of pages due for pageout. 89 * 90 * In addition, the structure contains the object 91 * and offset to which this page belongs (for pageout), 92 * and sundry status bits. 93 * 94 * Fields in this structure are locked either by the lock on the 95 * object that the page belongs to (O) or by the lock on the page 96 * queues (P). 97 */ 98 99 TAILQ_HEAD(pglist, vm_page); 100 101 struct vm_page { 102 TAILQ_ENTRY(vm_page) pageq; /* queue info for FIFO 103 * queue or free list (P) */ 104 TAILQ_ENTRY(vm_page) hashq; /* hash table links (O)*/ 105 TAILQ_ENTRY(vm_page) listq; /* pages in same object (O)*/ 106 107 vm_object_t object; /* which object am I in (O,P)*/ 108 vm_offset_t offset; /* offset into object (O,P) */ 109 110 u_short wire_count; /* wired down maps refs (P) */ 111 u_short flags; /* see below */ 112 short hold_count; /* page hold count */ 113 u_short act_count; /* page usage count */ 114 115 vm_offset_t phys_addr; /* physical address of page */ 116 }; 117 118 /* 119 * These are the flags defined for vm_page. 120 * 121 * Note: PG_FILLED and PG_DIRTY are added for the filesystems. 122 */ 123 #define PG_INACTIVE 0x0001 /* page is in inactive list (P) */ 124 #define PG_ACTIVE 0x0002 /* page is in active list (P) */ 125 #define PG_LAUNDRY 0x0004 /* page is being cleaned now (P)*/ 126 #define PG_CLEAN 0x0008 /* page has not been modified */ 127 #define PG_BUSY 0x0010 /* page is in transit (O) */ 128 #define PG_WANTED 0x0020 /* someone is waiting for page (O) */ 129 #define PG_TABLED 0x0040 /* page is in VP table (O) */ 130 #define PG_COPYONWRITE 0x0080 /* must copy page before changing (O) */ 131 #define PG_FICTITIOUS 0x0100 /* physical page doesn't exist (O) */ 132 #define PG_FAKE 0x0200 /* page is placeholder for pagein (O) */ 133 #define PG_FILLED 0x0400 /* client flag to set when filled */ 134 #define PG_DIRTY 0x0800 /* client flag to set when dirty */ 135 #define PG_REFERENCED 0x1000 /* page has been referenced */ 136 #define PG_PAGEROWNED 0x4000 /* DEBUG: async paging op in progress */ 137 #define PG_PTPAGE 0x8000 /* DEBUG: is a user page table page */ 138 139 #if VM_PAGE_DEBUG 140 #define VM_PAGE_CHECK(mem) { \ 141 if ((((unsigned int) mem) < ((unsigned int) &vm_page_array[0])) || \ 142 (((unsigned int) mem) > \ 143 ((unsigned int) &vm_page_array[last_page-first_page])) || \ 144 ((mem->flags & (PG_ACTIVE | PG_INACTIVE)) == \ 145 (PG_ACTIVE | PG_INACTIVE))) \ 146 panic("vm_page_check: not valid!"); \ 147 } 148 #else /* VM_PAGE_DEBUG */ 149 #define VM_PAGE_CHECK(mem) 150 #endif /* VM_PAGE_DEBUG */ 151 152 #ifdef KERNEL 153 /* 154 * Each pageable resident page falls into one of three lists: 155 * 156 * free 157 * Available for allocation now. 158 * inactive 159 * Not referenced in any map, but still has an 160 * object/offset-page mapping, and may be dirty. 161 * This is the list of pages that should be 162 * paged out next. 163 * active 164 * A list of pages which have been placed in 165 * at least one physical map. This list is 166 * ordered, in LRU-like fashion. 167 */ 168 169 extern 170 struct pglist vm_page_queue_free; /* memory free queue */ 171 extern 172 struct pglist vm_page_queue_active; /* active memory queue */ 173 extern 174 struct pglist vm_page_queue_inactive; /* inactive memory queue */ 175 176 extern 177 vm_page_t vm_page_array; /* First resident page in table */ 178 extern 179 long first_page; /* first physical page number */ 180 /* ... represented in vm_page_array */ 181 extern 182 long last_page; /* last physical page number */ 183 /* ... represented in vm_page_array */ 184 /* [INCLUSIVE] */ 185 extern 186 vm_offset_t first_phys_addr; /* physical address for first_page */ 187 extern 188 vm_offset_t last_phys_addr; /* physical address for last_page */ 189 190 #define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr) 191 192 #define IS_VM_PHYSADDR(pa) \ 193 ((pa) >= first_phys_addr && (pa) <= last_phys_addr) 194 195 #define PHYS_TO_VM_PAGE(pa) \ 196 (&vm_page_array[atop(pa) - first_page ]) 197 198 extern 199 simple_lock_data_t vm_page_queue_lock; /* lock on active and inactive 200 page queues */ 201 extern /* lock on free page queue */ 202 simple_lock_data_t vm_page_queue_free_lock; 203 204 /* 205 * Functions implemented as macros 206 */ 207 208 #define PAGE_ASSERT_WAIT(m, interruptible) { \ 209 (m)->flags |= PG_WANTED; \ 210 assert_wait((int) (m), (interruptible)); \ 211 } 212 213 #define PAGE_WAKEUP(m) { \ 214 (m)->flags &= ~PG_BUSY; \ 215 if ((m)->flags & PG_WANTED) { \ 216 (m)->flags &= ~PG_WANTED; \ 217 wakeup((caddr_t) (m)); \ 218 } \ 219 } 220 221 #define vm_page_lock_queues() simple_lock(&vm_page_queue_lock) 222 #define vm_page_unlock_queues() simple_unlock(&vm_page_queue_lock) 223 224 #define vm_page_set_modified(m) { (m)->flags &= ~PG_CLEAN; } 225 226 #define VM_PAGE_INIT(mem, object, offset) { \ 227 (mem)->flags = PG_BUSY | PG_CLEAN | PG_FAKE; \ 228 vm_page_insert((mem), (object), (offset)); \ 229 (mem)->wire_count = 0; \ 230 (mem)->hold_count = 0; \ 231 (mem)->act_count = 0; \ 232 } 233 234 void vm_page_activate __P((vm_page_t)); 235 vm_page_t vm_page_alloc __P((vm_object_t, vm_offset_t)); 236 void vm_page_copy __P((vm_page_t, vm_page_t)); 237 void vm_page_deactivate __P((vm_page_t)); 238 void vm_page_free __P((vm_page_t)); 239 void vm_page_insert __P((vm_page_t, vm_object_t, vm_offset_t)); 240 vm_page_t vm_page_lookup __P((vm_object_t, vm_offset_t)); 241 void vm_page_remove __P((vm_page_t)); 242 void vm_page_rename __P((vm_page_t, vm_object_t, vm_offset_t)); 243 vm_offset_t vm_page_startup __P((vm_offset_t, vm_offset_t, vm_offset_t)); 244 void vm_page_unwire __P((vm_page_t)); 245 void vm_page_wire __P((vm_page_t)); 246 boolean_t vm_page_zero_fill __P((vm_page_t)); 247 248 249 /* 250 * Keep page from being freed by the page daemon 251 * much of the same effect as wiring, except much lower 252 * overhead and should be used only for *very* temporary 253 * holding ("wiring"). 254 */ 255 static inline void 256 vm_page_hold(mem) 257 vm_page_t mem; 258 { 259 mem->hold_count++; 260 } 261 262 static inline void 263 vm_page_unhold(mem) 264 vm_page_t mem; 265 { 266 if( --mem->hold_count < 0) 267 panic("vm_page_unhold: hold count < 0!!!"); 268 } 269 270 #endif /* KERNEL */ 271 #endif /* !_VM_PAGE_ */ 272