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 * $FreeBSD$ 65 */ 66 67 /* 68 * Resident memory system definitions. 69 */ 70 71 #ifndef _VM_PAGE_ 72 #define _VM_PAGE_ 73 74 #if !defined(KLD_MODULE) 75 #include "opt_vmpage.h" 76 #endif 77 78 #include <vm/pmap.h> 79 #include <machine/atomic.h> 80 81 /* 82 * Management of resident (logical) pages. 83 * 84 * A small structure is kept for each resident 85 * page, indexed by page number. Each structure 86 * is an element of several lists: 87 * 88 * A hash table bucket used to quickly 89 * perform object/offset lookups 90 * 91 * A list of all pages for a given object, 92 * so they can be quickly deactivated at 93 * time of deallocation. 94 * 95 * An ordered list of pages due for pageout. 96 * 97 * In addition, the structure contains the object 98 * and offset to which this page belongs (for pageout), 99 * and sundry status bits. 100 * 101 * Fields in this structure are locked either by the lock on the 102 * object that the page belongs to (O) or by the lock on the page 103 * queues (P). 104 * 105 * The 'valid' and 'dirty' fields are distinct. A page may have dirty 106 * bits set without having associated valid bits set. This is used by 107 * NFS to implement piecemeal writes. 108 */ 109 110 TAILQ_HEAD(pglist, vm_page); 111 112 struct vm_page { 113 TAILQ_ENTRY(vm_page) pageq; /* queue info for FIFO queue or free list (P) */ 114 struct vm_page *hnext; /* hash table link (O,P) */ 115 TAILQ_ENTRY(vm_page) listq; /* pages in same object (O) */ 116 117 vm_object_t object; /* which object am I in (O,P)*/ 118 vm_pindex_t pindex; /* offset into object (O,P) */ 119 vm_offset_t phys_addr; /* physical address of page */ 120 u_short queue; /* page queue index */ 121 u_short flags, /* see below */ 122 pc; /* page color */ 123 u_short wire_count; /* wired down maps refs (P) */ 124 short hold_count; /* page hold count */ 125 u_char act_count; /* page usage count */ 126 u_char busy; /* page busy count */ 127 /* NOTE that these must support one bit per DEV_BSIZE in a page!!! */ 128 /* so, on normal X86 kernels, they must be at least 8 bits wide */ 129 #if PAGE_SIZE == 4096 130 u_char valid; /* map of valid DEV_BSIZE chunks */ 131 u_char dirty; /* map of dirty DEV_BSIZE chunks */ 132 #elif PAGE_SIZE == 8192 133 u_short valid; /* map of valid DEV_BSIZE chunks */ 134 u_short dirty; /* map of dirty DEV_BSIZE chunks */ 135 #endif 136 }; 137 138 /* 139 * note: currently use SWAPBLK_NONE as an absolute value rather then 140 * a flag bit. 141 */ 142 143 #define SWAPBLK_MASK ((daddr_t)((u_daddr_t)-1 >> 1)) /* mask */ 144 #define SWAPBLK_NONE ((daddr_t)((u_daddr_t)SWAPBLK_MASK + 1))/* flag */ 145 146 #if !defined(KLD_MODULE) 147 148 /* 149 * Page coloring parameters 150 */ 151 /* Each of PQ_FREE, and PQ_CACHE have PQ_HASH_SIZE entries */ 152 153 /* Define one of the following */ 154 #if defined(PQ_HUGECACHE) 155 #define PQ_PRIME1 31 /* Prime number somewhat less than PQ_HASH_SIZE */ 156 #define PQ_PRIME2 23 /* Prime number somewhat less than PQ_HASH_SIZE */ 157 #define PQ_L2_SIZE 256 /* A number of colors opt for 1M cache */ 158 #endif 159 160 /* Define one of the following */ 161 #if defined(PQ_LARGECACHE) 162 #define PQ_PRIME1 31 /* Prime number somewhat less than PQ_HASH_SIZE */ 163 #define PQ_PRIME2 23 /* Prime number somewhat less than PQ_HASH_SIZE */ 164 #define PQ_L2_SIZE 128 /* A number of colors opt for 512K cache */ 165 #endif 166 167 168 /* 169 * Use 'options PQ_NOOPT' to disable page coloring 170 */ 171 #if defined(PQ_NOOPT) 172 #define PQ_PRIME1 1 173 #define PQ_PRIME2 1 174 #define PQ_L2_SIZE 1 175 #endif 176 177 #if defined(PQ_NORMALCACHE) 178 #define PQ_PRIME1 5 /* Prime number somewhat less than PQ_HASH_SIZE */ 179 #define PQ_PRIME2 3 /* Prime number somewhat less than PQ_HASH_SIZE */ 180 #define PQ_L2_SIZE 16 /* A reasonable number of colors (opt for 64K cache) */ 181 #endif 182 183 #if defined(PQ_MEDIUMCACHE) 184 #define PQ_PRIME1 13 /* Prime number somewhat less than PQ_HASH_SIZE */ 185 #define PQ_PRIME2 7 /* Prime number somewhat less than PQ_HASH_SIZE */ 186 #define PQ_L2_SIZE 64 /* A number of colors opt for 256K cache */ 187 #endif 188 189 #if !defined(PQ_L2_SIZE) 190 #define PQ_PRIME1 9 /* Produces a good PQ_L2_SIZE/3 + PQ_PRIME1 */ 191 #define PQ_PRIME2 5 /* Prime number somewhat less than PQ_HASH_SIZE */ 192 #define PQ_L2_SIZE 32 /* 512KB or smaller, 4-way set-associative cache */ 193 #endif 194 195 #define PQ_L2_MASK (PQ_L2_SIZE - 1) 196 197 #if 1 198 #define PQ_NONE 0 199 #define PQ_FREE 1 200 #define PQ_INACTIVE (1 + 1*PQ_L2_SIZE) 201 #define PQ_ACTIVE (2 + 1*PQ_L2_SIZE) 202 #define PQ_CACHE (3 + 1*PQ_L2_SIZE) 203 #define PQ_COUNT (3 + 2*PQ_L2_SIZE) 204 #else 205 #define PQ_NONE PQ_COUNT 206 #define PQ_FREE 0 207 #define PQ_INACTIVE PQ_L2_SIZE 208 #define PQ_ACTIVE (1 + PQ_L2_SIZE) 209 #define PQ_CACHE (2 + PQ_L2_SIZE) 210 #define PQ_COUNT (2 + 2*PQ_L2_SIZE) 211 #endif 212 213 extern struct vpgqueues { 214 struct pglist *pl; 215 int *cnt; 216 int lcnt; 217 } vm_page_queues[PQ_COUNT]; 218 219 #endif 220 221 /* 222 * These are the flags defined for vm_page. 223 * 224 * Note: PG_FILLED and PG_DIRTY are added for the filesystems. 225 */ 226 #define PG_BUSY 0x0001 /* page is in transit (O) */ 227 #define PG_WANTED 0x0002 /* someone is waiting for page (O) */ 228 #define PG_FICTITIOUS 0x0008 /* physical page doesn't exist (O) */ 229 #define PG_WRITEABLE 0x0010 /* page is mapped writeable */ 230 #define PG_MAPPED 0x0020 /* page is mapped */ 231 #define PG_ZERO 0x0040 /* page is zeroed */ 232 #define PG_REFERENCED 0x0080 /* page has been referenced */ 233 #define PG_CLEANCHK 0x0100 /* page will be checked for cleaning */ 234 #define PG_SWAPINPROG 0x0200 /* swap I/O in progress on page */ 235 236 /* 237 * Misc constants. 238 */ 239 240 #define ACT_DECLINE 1 241 #define ACT_ADVANCE 3 242 #define ACT_INIT 5 243 #define ACT_MAX 64 244 #define PFCLUSTER_BEHIND 3 245 #define PFCLUSTER_AHEAD 3 246 247 #ifdef KERNEL 248 /* 249 * Each pageable resident page falls into one of four lists: 250 * 251 * free 252 * Available for allocation now. 253 * 254 * The following are all LRU sorted: 255 * 256 * cache 257 * Almost available for allocation. Still in an 258 * object, but clean and immediately freeable at 259 * non-interrupt times. 260 * 261 * inactive 262 * Low activity, candidates for reclamation. 263 * This is the list of pages that should be 264 * paged out next. 265 * 266 * active 267 * Pages that are "active" i.e. they have been 268 * recently referenced. 269 * 270 * zero 271 * Pages that are really free and have been pre-zeroed 272 * 273 */ 274 275 #if !defined(KLD_MODULE) 276 277 extern struct pglist vm_page_queue_free[PQ_L2_SIZE];/* memory free queue */ 278 extern struct pglist vm_page_queue_active; /* active memory queue */ 279 extern struct pglist vm_page_queue_inactive; /* inactive memory queue */ 280 extern struct pglist vm_page_queue_cache[PQ_L2_SIZE];/* cache memory queue */ 281 282 #endif 283 284 extern int vm_page_zero_count; 285 286 extern vm_page_t vm_page_array; /* First resident page in table */ 287 extern long first_page; /* first physical page number */ 288 289 #define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr) 290 291 #define PHYS_TO_VM_PAGE(pa) \ 292 (&vm_page_array[atop(pa) - first_page ]) 293 294 /* 295 * Functions implemented as macros 296 */ 297 298 static __inline void 299 vm_page_flag_set(vm_page_t m, unsigned int bits) 300 { 301 atomic_set_short(&(m)->flags, bits); 302 } 303 304 static __inline void 305 vm_page_flag_clear(vm_page_t m, unsigned int bits) 306 { 307 atomic_clear_short(&(m)->flags, bits); 308 } 309 310 #if 0 311 static __inline void 312 vm_page_assert_wait(vm_page_t m, int interruptible) 313 { 314 vm_page_flag_set(m, PG_WANTED); 315 assert_wait((int) m, interruptible); 316 } 317 #endif 318 319 static __inline void 320 vm_page_busy(vm_page_t m) 321 { 322 KASSERT((m->flags & PG_BUSY) == 0, ("vm_page_busy: page already busy!!!")); 323 vm_page_flag_set(m, PG_BUSY); 324 } 325 326 /* 327 * vm_page_flash: 328 * 329 * wakeup anyone waiting for the page. 330 */ 331 332 static __inline void 333 vm_page_flash(vm_page_t m) 334 { 335 if (m->flags & PG_WANTED) { 336 vm_page_flag_clear(m, PG_WANTED); 337 wakeup(m); 338 } 339 } 340 341 /* 342 * vm_page_wakeup: 343 * 344 * clear the PG_BUSY flag and wakeup anyone waiting for the 345 * page. 346 * 347 */ 348 349 static __inline void 350 vm_page_wakeup(vm_page_t m) 351 { 352 KASSERT(m->flags & PG_BUSY, ("vm_page_wakeup: page not busy!!!")); 353 vm_page_flag_clear(m, PG_BUSY); 354 vm_page_flash(m); 355 } 356 357 /* 358 * 359 * 360 */ 361 362 static __inline void 363 vm_page_io_start(vm_page_t m) 364 { 365 atomic_add_char(&(m)->busy, 1); 366 } 367 368 static __inline void 369 vm_page_io_finish(vm_page_t m) 370 { 371 atomic_subtract_char(&m->busy, 1); 372 if (m->busy == 0) 373 vm_page_flash(m); 374 } 375 376 377 #if PAGE_SIZE == 4096 378 #define VM_PAGE_BITS_ALL 0xff 379 #endif 380 381 #if PAGE_SIZE == 8192 382 #define VM_PAGE_BITS_ALL 0xffff 383 #endif 384 385 #define VM_ALLOC_NORMAL 0 386 #define VM_ALLOC_INTERRUPT 1 387 #define VM_ALLOC_SYSTEM 2 388 #define VM_ALLOC_ZERO 3 389 #define VM_ALLOC_RETRY 0x80 390 391 void vm_page_activate __P((vm_page_t)); 392 vm_page_t vm_page_alloc __P((vm_object_t, vm_pindex_t, int)); 393 vm_page_t vm_page_grab __P((vm_object_t, vm_pindex_t, int)); 394 void vm_page_cache __P((register vm_page_t)); 395 void vm_page_dontneed __P((register vm_page_t)); 396 static __inline void vm_page_copy __P((vm_page_t, vm_page_t)); 397 static __inline void vm_page_free __P((vm_page_t)); 398 static __inline void vm_page_free_zero __P((vm_page_t)); 399 void vm_page_deactivate __P((vm_page_t)); 400 void vm_page_insert __P((vm_page_t, vm_object_t, vm_pindex_t)); 401 vm_page_t vm_page_lookup __P((vm_object_t, vm_pindex_t)); 402 void vm_page_remove __P((vm_page_t)); 403 void vm_page_rename __P((vm_page_t, vm_object_t, vm_pindex_t)); 404 vm_offset_t vm_page_startup __P((vm_offset_t, vm_offset_t, vm_offset_t)); 405 void vm_page_unwire __P((vm_page_t, int)); 406 void vm_page_wire __P((vm_page_t)); 407 void vm_page_unqueue __P((vm_page_t)); 408 void vm_page_unqueue_nowakeup __P((vm_page_t)); 409 void vm_page_set_validclean __P((vm_page_t, int, int)); 410 void vm_page_set_dirty __P((vm_page_t, int, int)); 411 void vm_page_clear_dirty __P((vm_page_t, int, int)); 412 void vm_page_set_invalid __P((vm_page_t, int, int)); 413 static __inline boolean_t vm_page_zero_fill __P((vm_page_t)); 414 int vm_page_is_valid __P((vm_page_t, int, int)); 415 void vm_page_test_dirty __P((vm_page_t)); 416 int vm_page_bits __P((int, int)); 417 vm_page_t _vm_page_list_find __P((int, int)); 418 #if 0 419 int vm_page_sleep(vm_page_t m, char *msg, char *busy); 420 int vm_page_asleep(vm_page_t m, char *msg, char *busy); 421 #endif 422 void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid); 423 void vm_page_free_toq(vm_page_t m); 424 425 /* 426 * Keep page from being freed by the page daemon 427 * much of the same effect as wiring, except much lower 428 * overhead and should be used only for *very* temporary 429 * holding ("wiring"). 430 */ 431 static __inline void 432 vm_page_hold(vm_page_t mem) 433 { 434 mem->hold_count++; 435 } 436 437 static __inline void 438 vm_page_unhold(vm_page_t mem) 439 { 440 --mem->hold_count; 441 KASSERT(mem->hold_count >= 0, ("vm_page_unhold: hold count < 0!!!")); 442 } 443 444 /* 445 * vm_page_protect: 446 * 447 * Reduce the protection of a page. This routine never 448 * raises the protection and therefore can be safely 449 * called if the page is already at VM_PROT_NONE ( it 450 * will be a NOP effectively ). 451 */ 452 453 static __inline void 454 vm_page_protect(vm_page_t mem, int prot) 455 { 456 if (prot == VM_PROT_NONE) { 457 if (mem->flags & (PG_WRITEABLE|PG_MAPPED)) { 458 pmap_page_protect(VM_PAGE_TO_PHYS(mem), VM_PROT_NONE); 459 vm_page_flag_clear(mem, PG_WRITEABLE|PG_MAPPED); 460 } 461 } else if ((prot == VM_PROT_READ) && (mem->flags & PG_WRITEABLE)) { 462 pmap_page_protect(VM_PAGE_TO_PHYS(mem), VM_PROT_READ); 463 vm_page_flag_clear(mem, PG_WRITEABLE); 464 } 465 } 466 467 /* 468 * vm_page_zero_fill: 469 * 470 * Zero-fill the specified page. 471 * Written as a standard pagein routine, to 472 * be used by the zero-fill object. 473 */ 474 static __inline boolean_t 475 vm_page_zero_fill(m) 476 vm_page_t m; 477 { 478 pmap_zero_page(VM_PAGE_TO_PHYS(m)); 479 return (TRUE); 480 } 481 482 /* 483 * vm_page_copy: 484 * 485 * Copy one page to another 486 */ 487 static __inline void 488 vm_page_copy(src_m, dest_m) 489 vm_page_t src_m; 490 vm_page_t dest_m; 491 { 492 pmap_copy_page(VM_PAGE_TO_PHYS(src_m), VM_PAGE_TO_PHYS(dest_m)); 493 dest_m->valid = VM_PAGE_BITS_ALL; 494 } 495 496 /* 497 * vm_page_free: 498 * 499 * Free a page 500 * 501 * The clearing of PG_ZERO is a temporary safety until the code can be 502 * reviewed to determine that PG_ZERO is being properly cleared on 503 * write faults or maps. PG_ZERO was previously cleared in 504 * vm_page_alloc(). 505 */ 506 static __inline void 507 vm_page_free(m) 508 vm_page_t m; 509 { 510 vm_page_flag_clear(m, PG_ZERO); 511 vm_page_free_toq(m); 512 } 513 514 /* 515 * vm_page_free_zero: 516 * 517 * Free a page to the zerod-pages queue 518 */ 519 static __inline void 520 vm_page_free_zero(m) 521 vm_page_t m; 522 { 523 vm_page_flag_set(m, PG_ZERO); 524 vm_page_free_toq(m); 525 } 526 527 /* 528 * vm_page_sleep_busy: 529 * 530 * Wait until page is no longer PG_BUSY or (if also_m_busy is TRUE) 531 * m->busy is zero. Returns TRUE if it had to sleep ( including if 532 * it almost had to sleep and made temporary spl*() mods), FALSE 533 * otherwise. 534 * 535 * This routine assumes that interrupts can only remove the busy 536 * status from a page, not set the busy status or change it from 537 * PG_BUSY to m->busy or vise versa (which would create a timing 538 * window). 539 * 540 * Note that being an inline, this code will be well optimized. 541 */ 542 543 static __inline int 544 vm_page_sleep_busy(vm_page_t m, int also_m_busy, const char *msg) 545 { 546 if ((m->flags & PG_BUSY) || (also_m_busy && m->busy)) { 547 int s = splvm(); 548 if ((m->flags & PG_BUSY) || (also_m_busy && m->busy)) { 549 /* 550 * Page is busy. Wait and retry. 551 */ 552 vm_page_flag_set(m, PG_WANTED | PG_REFERENCED); 553 tsleep(m, PVM, msg, 0); 554 } 555 splx(s); 556 return(TRUE); 557 /* not reached */ 558 } 559 return(FALSE); 560 } 561 562 /* 563 * vm_page_dirty: 564 * 565 * make page all dirty 566 */ 567 568 static __inline void 569 vm_page_dirty(vm_page_t m) 570 { 571 #if !defined(KLD_MODULE) 572 KASSERT(m->queue - m->pc != PQ_CACHE, ("vm_page_dirty: page in cache!")); 573 #endif 574 m->dirty = VM_PAGE_BITS_ALL; 575 } 576 577 /* 578 * vm_page_undirty: 579 * 580 * Set page to not be dirty. Note: does not clear pmap modify bits 581 */ 582 583 static __inline void 584 vm_page_undirty(vm_page_t m) 585 { 586 m->dirty = 0; 587 } 588 589 #if !defined(KLD_MODULE) 590 591 static __inline vm_page_t 592 vm_page_list_find(int basequeue, int index, boolean_t prefer_zero) 593 { 594 vm_page_t m; 595 596 #if PQ_L2_SIZE > 1 597 if (prefer_zero) { 598 m = TAILQ_LAST(vm_page_queues[basequeue+index].pl, pglist); 599 } else { 600 m = TAILQ_FIRST(vm_page_queues[basequeue+index].pl); 601 } 602 if (m == NULL) 603 m = _vm_page_list_find(basequeue, index); 604 #else 605 if (prefer_zero) { 606 m = TAILQ_LAST(vm_page_queues[basequeue].pl, pglist); 607 } else { 608 m = TAILQ_FIRST(vm_page_queues[basequeue].pl); 609 } 610 #endif 611 return(m); 612 } 613 614 #endif 615 616 #endif /* KERNEL */ 617 #endif /* !_VM_PAGE_ */ 618