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 1.19 1995/07/13 08:48:38 davidg Exp $ 65 */ 66 67 /* 68 * Resident memory system definitions. 69 */ 70 71 #ifndef _VM_PAGE_ 72 #define _VM_PAGE_ 73 74 #include <vm/pmap.h> 75 /* 76 * Management of resident (logical) pages. 77 * 78 * A small structure is kept for each resident 79 * page, indexed by page number. Each structure 80 * is an element of several lists: 81 * 82 * A hash table bucket used to quickly 83 * perform object/offset lookups 84 * 85 * A list of all pages for a given object, 86 * so they can be quickly deactivated at 87 * time of deallocation. 88 * 89 * An ordered list of pages due for pageout. 90 * 91 * In addition, the structure contains the object 92 * and offset to which this page belongs (for pageout), 93 * and sundry status bits. 94 * 95 * Fields in this structure are locked either by the lock on the 96 * object that the page belongs to (O) or by the lock on the page 97 * queues (P). 98 */ 99 100 TAILQ_HEAD(pglist, vm_page); 101 102 struct vm_page { 103 TAILQ_ENTRY(vm_page) pageq; /* queue info for FIFO 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 vm_offset_t phys_addr; /* physical address of page */ 110 111 u_short wire_count; /* wired down maps refs (P) */ 112 u_short flags; /* see below */ 113 short hold_count; /* page hold count */ 114 u_short act_count; /* page usage count */ 115 u_short bmapped; /* number of buffers mapped */ 116 u_short busy; /* page busy count */ 117 u_short valid; /* map of valid DEV_BSIZE chunks */ 118 u_short dirty; /* map of dirty DEV_BSIZE chunks */ 119 }; 120 121 /* 122 * These are the flags defined for vm_page. 123 * 124 * Note: PG_FILLED and PG_DIRTY are added for the filesystems. 125 */ 126 #define PG_INACTIVE 0x0001 /* page is in inactive list (P) */ 127 #define PG_ACTIVE 0x0002 /* page is in active list (P) */ 128 #define PG_BUSY 0x0010 /* page is in transit (O) */ 129 #define PG_WANTED 0x0020 /* someone is waiting for page (O) */ 130 #define PG_TABLED 0x0040 /* page is in VP table (O) */ 131 #define PG_COPYONWRITE 0x0080 /* must copy page before changing (O) */ 132 #define PG_FICTITIOUS 0x0100 /* physical page doesn't exist (O) */ 133 #define PG_WRITEABLE 0x0200 /* page is mapped writeable */ 134 #define PG_MAPPED 0x0400 /* page is mapped */ 135 #define PG_ZERO 0x0800 /* page is zeroed */ 136 #define PG_REFERENCED 0x1000 /* page has been referenced */ 137 #define PG_CACHE 0x4000 /* On VMIO cache */ 138 #define PG_FREE 0x8000 /* page is in free list */ 139 140 /* 141 * Misc constants. 142 */ 143 144 #define ACT_DECLINE 1 145 #define ACT_ADVANCE 3 146 #define ACT_MAX 100 147 #define PFCLUSTER_BEHIND 3 148 #define PFCLUSTER_AHEAD 3 149 150 #ifdef KERNEL 151 /* 152 * Each pageable resident page falls into one of four lists: 153 * 154 * free 155 * Available for allocation now. 156 * 157 * The following are all LRU sorted: 158 * 159 * cache 160 * Almost available for allocation. Still in an 161 * object, but clean and immediately freeable at 162 * non-interrupt times. 163 * 164 * inactive 165 * Low activity, candidates for reclaimation. 166 * This is the list of pages that should be 167 * paged out next. 168 * 169 * active 170 * Pages that are "active" i.e. they have been 171 * recently referenced. 172 * 173 * zero 174 * Pages that are really free and have been pre-zeroed 175 * 176 */ 177 178 extern struct pglist vm_page_queue_free; /* memory free queue */ 179 extern struct pglist vm_page_queue_zero; /* zeroed memory free queue */ 180 extern struct pglist vm_page_queue_active; /* active memory queue */ 181 extern struct pglist vm_page_queue_inactive; /* inactive memory queue */ 182 extern struct pglist vm_page_queue_cache; /* cache memory queue */ 183 184 extern vm_page_t vm_page_array; /* First resident page in table */ 185 extern long first_page; /* first physical page number */ 186 187 /* ... represented in vm_page_array */ 188 extern long last_page; /* last physical page number */ 189 190 /* ... represented in vm_page_array */ 191 /* [INCLUSIVE] */ 192 extern vm_offset_t first_phys_addr; /* physical address for first_page */ 193 extern vm_offset_t last_phys_addr; /* physical address for last_page */ 194 195 #define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr) 196 197 #define IS_VM_PHYSADDR(pa) \ 198 ((pa) >= first_phys_addr && (pa) <= last_phys_addr) 199 200 #define PHYS_TO_VM_PAGE(pa) \ 201 (&vm_page_array[atop(pa) - first_page ]) 202 203 /* 204 * Functions implemented as macros 205 */ 206 207 #define PAGE_ASSERT_WAIT(m, interruptible) { \ 208 (m)->flags |= PG_WANTED; \ 209 assert_wait((int) (m), (interruptible)); \ 210 } 211 212 #define PAGE_WAKEUP(m) { \ 213 (m)->flags &= ~PG_BUSY; \ 214 if ((m)->flags & PG_WANTED) { \ 215 (m)->flags &= ~PG_WANTED; \ 216 wakeup((caddr_t) (m)); \ 217 } \ 218 } 219 220 #if PAGE_SIZE == 4096 221 #define VM_PAGE_BITS_ALL 0xff 222 #endif 223 224 #if PAGE_SIZE == 8192 225 #define VM_PAGE_BITS_ALL 0xffff 226 #endif 227 228 #define VM_ALLOC_NORMAL 0 229 #define VM_ALLOC_INTERRUPT 1 230 #define VM_ALLOC_SYSTEM 2 231 #define VM_ALLOC_ZERO 0x80 232 233 void vm_page_activate __P((vm_page_t)); 234 vm_page_t vm_page_alloc __P((vm_object_t, vm_offset_t, int)); 235 void vm_page_cache __P((register vm_page_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 void vm_page_set_dirty __P((vm_page_t, int, int)); 248 void vm_page_set_clean __P((vm_page_t, int, int)); 249 int vm_page_is_clean __P((vm_page_t, int, int)); 250 void vm_page_set_valid __P((vm_page_t, int, int)); 251 void vm_page_set_validclean __P((vm_page_t, int, int)); 252 void vm_page_set_invalid __P((vm_page_t, int, int)); 253 int vm_page_is_valid __P((vm_page_t, int, int)); 254 void vm_page_test_dirty __P((vm_page_t)); 255 void vm_page_unqueue __P((vm_page_t )); 256 int vm_page_bits __P((int, int)); 257 258 259 /* 260 * Keep page from being freed by the page daemon 261 * much of the same effect as wiring, except much lower 262 * overhead and should be used only for *very* temporary 263 * holding ("wiring"). 264 */ 265 static __inline void 266 vm_page_hold(vm_page_t mem) 267 { 268 mem->hold_count++; 269 } 270 271 #ifdef DIAGNOSTIC 272 #include <sys/systm.h> /* make GCC shut up */ 273 #endif 274 275 static __inline void 276 vm_page_unhold(vm_page_t mem) 277 { 278 #ifdef DIAGNOSTIC 279 if (--mem->hold_count < 0) 280 panic("vm_page_unhold: hold count < 0!!!"); 281 #else 282 --mem->hold_count; 283 #endif 284 } 285 286 static __inline void 287 vm_page_protect(vm_page_t mem, int prot) 288 { 289 if (prot == VM_PROT_NONE) { 290 if (mem->flags & (PG_WRITEABLE|PG_MAPPED)) { 291 pmap_page_protect(VM_PAGE_TO_PHYS(mem), prot); 292 mem->flags &= ~(PG_WRITEABLE|PG_MAPPED); 293 } 294 } else if ((prot == VM_PROT_READ) && (mem->flags & PG_WRITEABLE)) { 295 pmap_page_protect(VM_PAGE_TO_PHYS(mem), prot); 296 mem->flags &= ~PG_WRITEABLE; 297 } 298 } 299 300 301 #endif /* KERNEL */ 302 #endif /* !_VM_PAGE_ */ 303