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 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * from: @(#)vm_page.h 8.2 (Berkeley) 12/13/93 33 * 34 * 35 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 36 * All rights reserved. 37 * 38 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 39 * 40 * Permission to use, copy, modify and distribute this software and 41 * its documentation is hereby granted, provided that both the copyright 42 * notice and this permission notice appear in all copies of the 43 * software, derivative works or modified versions, and any portions 44 * thereof, and that both notices appear in supporting documentation. 45 * 46 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 47 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 48 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 49 * 50 * Carnegie Mellon requests users of this software to return to 51 * 52 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 53 * School of Computer Science 54 * Carnegie Mellon University 55 * Pittsburgh PA 15213-3890 56 * 57 * any improvements or extensions that they make and grant Carnegie the 58 * rights to redistribute these changes. 59 * 60 * $FreeBSD$ 61 */ 62 63 /* 64 * Resident memory system definitions. 65 */ 66 67 #ifndef _VM_PAGE_ 68 #define _VM_PAGE_ 69 70 #include <vm/pmap.h> 71 72 /* 73 * Management of resident (logical) pages. 74 * 75 * A small structure is kept for each resident 76 * page, indexed by page number. Each structure 77 * is an element of several lists: 78 * 79 * A hash table bucket used to quickly 80 * perform object/offset lookups 81 * 82 * A list of all pages for a given object, 83 * so they can be quickly deactivated at 84 * time of deallocation. 85 * 86 * An ordered list of pages due for pageout. 87 * 88 * In addition, the structure contains the object 89 * and offset to which this page belongs (for pageout), 90 * and sundry status bits. 91 * 92 * In general, operations on this structure's mutable fields are 93 * synchronized using either one of or a combination of the lock on the 94 * object that the page belongs to (O), the pool lock for the page (P), 95 * or the lock for either the free or paging queues (Q). If a field is 96 * annotated below with two of these locks, then holding either lock is 97 * sufficient for read access, but both locks are required for write 98 * access. 99 * 100 * In contrast, the synchronization of accesses to the page's 101 * dirty field is machine dependent (M). In the 102 * machine-independent layer, the lock on the object that the 103 * page belongs to must be held in order to operate on the field. 104 * However, the pmap layer is permitted to set all bits within 105 * the field without holding that lock. If the underlying 106 * architecture does not support atomic read-modify-write 107 * operations on the field's type, then the machine-independent 108 * layer uses a 32-bit atomic on the aligned 32-bit word that 109 * contains the dirty field. In the machine-independent layer, 110 * the implementation of read-modify-write operations on the 111 * field is encapsulated in vm_page_clear_dirty_mask(). 112 */ 113 114 TAILQ_HEAD(pglist, vm_page); 115 116 #if PAGE_SIZE == 4096 117 #define VM_PAGE_BITS_ALL 0xffu 118 typedef uint8_t vm_page_bits_t; 119 #elif PAGE_SIZE == 8192 120 #define VM_PAGE_BITS_ALL 0xffffu 121 typedef uint16_t vm_page_bits_t; 122 #elif PAGE_SIZE == 16384 123 #define VM_PAGE_BITS_ALL 0xffffffffu 124 typedef uint32_t vm_page_bits_t; 125 #elif PAGE_SIZE == 32768 126 #define VM_PAGE_BITS_ALL 0xfffffffffffffffflu 127 typedef uint64_t vm_page_bits_t; 128 #endif 129 130 struct vm_page { 131 TAILQ_ENTRY(vm_page) pageq; /* queue info for FIFO queue or free list (Q) */ 132 TAILQ_ENTRY(vm_page) listq; /* pages in same object (O) */ 133 struct vm_page *left; /* splay tree link (O) */ 134 struct vm_page *right; /* splay tree link (O) */ 135 136 vm_object_t object; /* which object am I in (O,P)*/ 137 vm_pindex_t pindex; /* offset into object (O,P) */ 138 vm_paddr_t phys_addr; /* physical address of page */ 139 struct md_page md; /* machine dependant stuff */ 140 uint8_t queue; /* page queue index (P,Q) */ 141 int8_t segind; 142 short hold_count; /* page hold count (P) */ 143 uint8_t order; /* index of the buddy queue */ 144 uint8_t pool; 145 u_short cow; /* page cow mapping count (P) */ 146 u_int wire_count; /* wired down maps refs (P) */ 147 uint8_t aflags; /* access is atomic */ 148 uint8_t flags; /* see below, often immutable after alloc */ 149 u_short oflags; /* page flags (O) */ 150 u_char act_count; /* page usage count (O) */ 151 u_char busy; /* page busy count (O) */ 152 /* NOTE that these must support one bit per DEV_BSIZE in a page!!! */ 153 /* so, on normal X86 kernels, they must be at least 8 bits wide */ 154 vm_page_bits_t valid; /* map of valid DEV_BSIZE chunks (O) */ 155 vm_page_bits_t dirty; /* map of dirty DEV_BSIZE chunks (M) */ 156 }; 157 158 /* 159 * Page flags stored in oflags: 160 * 161 * Access to these page flags is synchronized by the lock on the object 162 * containing the page (O). 163 * 164 * Note: VPO_UNMANAGED (used by OBJT_DEVICE, OBJT_PHYS and OBJT_SG) 165 * indicates that the page is not under PV management but 166 * otherwise should be treated as a normal page. Pages not 167 * under PV management cannot be paged out via the 168 * object/vm_page_t because there is no knowledge of their pte 169 * mappings, and such pages are also not on any PQ queue. 170 * 171 */ 172 #define VPO_BUSY 0x0001 /* page is in transit */ 173 #define VPO_WANTED 0x0002 /* someone is waiting for page */ 174 #define VPO_UNMANAGED 0x0004 /* No PV management for page */ 175 #define VPO_SWAPINPROG 0x0200 /* swap I/O in progress on page */ 176 #define VPO_NOSYNC 0x0400 /* do not collect for syncer */ 177 178 #define PQ_NONE 255 179 #define PQ_INACTIVE 0 180 #define PQ_ACTIVE 1 181 #define PQ_HOLD 2 182 #define PQ_COUNT 3 183 184 struct vpgqueues { 185 struct pglist pl; 186 int *cnt; 187 }; 188 189 extern struct vpgqueues vm_page_queues[PQ_COUNT]; 190 191 struct vpglocks { 192 struct mtx data; 193 char pad[CACHE_LINE_SIZE - sizeof(struct mtx)]; 194 } __aligned(CACHE_LINE_SIZE); 195 196 extern struct vpglocks vm_page_queue_free_lock; 197 extern struct vpglocks pa_lock[]; 198 199 #if defined(__arm__) 200 #define PDRSHIFT PDR_SHIFT 201 #elif !defined(PDRSHIFT) 202 #define PDRSHIFT 21 203 #endif 204 205 #define pa_index(pa) ((pa) >> PDRSHIFT) 206 #define PA_LOCKPTR(pa) &pa_lock[pa_index((pa)) % PA_LOCK_COUNT].data 207 #define PA_LOCKOBJPTR(pa) ((struct lock_object *)PA_LOCKPTR((pa))) 208 #define PA_LOCK(pa) mtx_lock(PA_LOCKPTR(pa)) 209 #define PA_TRYLOCK(pa) mtx_trylock(PA_LOCKPTR(pa)) 210 #define PA_UNLOCK(pa) mtx_unlock(PA_LOCKPTR(pa)) 211 #define PA_UNLOCK_COND(pa) \ 212 do { \ 213 if ((pa) != 0) { \ 214 PA_UNLOCK((pa)); \ 215 (pa) = 0; \ 216 } \ 217 } while (0) 218 219 #define PA_LOCK_ASSERT(pa, a) mtx_assert(PA_LOCKPTR(pa), (a)) 220 221 #ifdef KLD_MODULE 222 #define vm_page_lock(m) vm_page_lock_KBI((m), LOCK_FILE, LOCK_LINE) 223 #define vm_page_unlock(m) vm_page_unlock_KBI((m), LOCK_FILE, LOCK_LINE) 224 #define vm_page_trylock(m) vm_page_trylock_KBI((m), LOCK_FILE, LOCK_LINE) 225 #if defined(INVARIANTS) 226 #define vm_page_lock_assert(m, a) \ 227 vm_page_lock_assert_KBI((m), (a), __FILE__, __LINE__) 228 #else 229 #define vm_page_lock_assert(m, a) 230 #endif 231 #else /* !KLD_MODULE */ 232 #define vm_page_lockptr(m) (PA_LOCKPTR(VM_PAGE_TO_PHYS((m)))) 233 #define vm_page_lock(m) mtx_lock(vm_page_lockptr((m))) 234 #define vm_page_unlock(m) mtx_unlock(vm_page_lockptr((m))) 235 #define vm_page_trylock(m) mtx_trylock(vm_page_lockptr((m))) 236 #define vm_page_lock_assert(m, a) mtx_assert(vm_page_lockptr((m)), (a)) 237 #endif 238 239 #define vm_page_queue_free_mtx vm_page_queue_free_lock.data 240 241 /* 242 * The vm_page's aflags are updated using atomic operations. To set or clear 243 * these flags, the functions vm_page_aflag_set() and vm_page_aflag_clear() 244 * must be used. Neither these flags nor these functions are part of the KBI. 245 * 246 * PGA_REFERENCED may be cleared only if the object containing the page is 247 * locked. It is set by both the MI and MD VM layers. However, kernel 248 * loadable modules should not directly set this flag. They should call 249 * vm_page_reference() instead. 250 * 251 * PGA_WRITEABLE is set exclusively on managed pages by pmap_enter(). When it 252 * does so, the page must be VPO_BUSY. The MI VM layer must never access this 253 * flag directly. Instead, it should call pmap_page_is_write_mapped(). 254 * 255 * PGA_EXECUTABLE may be set by pmap routines, and indicates that a page has 256 * at least one executable mapping. It is not consumed by the MI VM layer. 257 */ 258 #define PGA_WRITEABLE 0x01 /* page may be mapped writeable */ 259 #define PGA_REFERENCED 0x02 /* page has been referenced */ 260 #define PGA_EXECUTABLE 0x04 /* page may be mapped executable */ 261 262 /* 263 * Page flags. If changed at any other time than page allocation or 264 * freeing, the modification must be protected by the vm_page lock. 265 */ 266 #define PG_CACHED 0x01 /* page is cached */ 267 #define PG_FREE 0x02 /* page is free */ 268 #define PG_FICTITIOUS 0x04 /* physical page doesn't exist */ 269 #define PG_ZERO 0x08 /* page is zeroed */ 270 #define PG_MARKER 0x10 /* special queue marker page */ 271 #define PG_SLAB 0x20 /* object pointer is actually a slab */ 272 #define PG_WINATCFLS 0x40 /* flush dirty page on inactive q */ 273 #define PG_NODUMP 0x80 /* don't include this page in a dump */ 274 275 /* 276 * Misc constants. 277 */ 278 #define ACT_DECLINE 1 279 #define ACT_ADVANCE 3 280 #define ACT_INIT 5 281 #define ACT_MAX 64 282 283 #ifdef _KERNEL 284 285 #include <sys/systm.h> 286 287 #include <machine/atomic.h> 288 289 /* 290 * Each pageable resident page falls into one of five lists: 291 * 292 * free 293 * Available for allocation now. 294 * 295 * cache 296 * Almost available for allocation. Still associated with 297 * an object, but clean and immediately freeable. 298 * 299 * hold 300 * Will become free after a pending I/O operation 301 * completes. 302 * 303 * The following lists are LRU sorted: 304 * 305 * inactive 306 * Low activity, candidates for reclamation. 307 * This is the list of pages that should be 308 * paged out next. 309 * 310 * active 311 * Pages that are "active" i.e. they have been 312 * recently referenced. 313 * 314 */ 315 316 extern int vm_page_zero_count; 317 318 extern vm_page_t vm_page_array; /* First resident page in table */ 319 extern long vm_page_array_size; /* number of vm_page_t's */ 320 extern long first_page; /* first physical page number */ 321 322 #define VM_PAGE_IS_FREE(m) (((m)->flags & PG_FREE) != 0) 323 324 #define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr) 325 326 vm_page_t vm_phys_paddr_to_vm_page(vm_paddr_t pa); 327 328 vm_page_t PHYS_TO_VM_PAGE(vm_paddr_t pa); 329 330 extern struct vpglocks vm_page_queue_lock; 331 332 #define vm_page_queue_mtx vm_page_queue_lock.data 333 #define vm_page_lock_queues() mtx_lock(&vm_page_queue_mtx) 334 #define vm_page_unlock_queues() mtx_unlock(&vm_page_queue_mtx) 335 336 /* page allocation classes: */ 337 #define VM_ALLOC_NORMAL 0 338 #define VM_ALLOC_INTERRUPT 1 339 #define VM_ALLOC_SYSTEM 2 340 #define VM_ALLOC_CLASS_MASK 3 341 /* page allocation flags: */ 342 #define VM_ALLOC_WIRED 0x0020 /* non pageable */ 343 #define VM_ALLOC_ZERO 0x0040 /* Try to obtain a zeroed page */ 344 #define VM_ALLOC_RETRY 0x0080 /* Mandatory with vm_page_grab() */ 345 #define VM_ALLOC_NOOBJ 0x0100 /* No associated object */ 346 #define VM_ALLOC_NOBUSY 0x0200 /* Do not busy the page */ 347 #define VM_ALLOC_IFCACHED 0x0400 /* Fail if the page is not cached */ 348 #define VM_ALLOC_IFNOTCACHED 0x0800 /* Fail if the page is cached */ 349 #define VM_ALLOC_IGN_SBUSY 0x1000 /* vm_page_grab() only */ 350 #define VM_ALLOC_NODUMP 0x2000 /* don't include in dump */ 351 352 #define VM_ALLOC_COUNT_SHIFT 16 353 #define VM_ALLOC_COUNT(count) ((count) << VM_ALLOC_COUNT_SHIFT) 354 355 void vm_page_busy(vm_page_t m); 356 void vm_page_flash(vm_page_t m); 357 void vm_page_io_start(vm_page_t m); 358 void vm_page_io_finish(vm_page_t m); 359 void vm_page_hold(vm_page_t mem); 360 void vm_page_unhold(vm_page_t mem); 361 void vm_page_free(vm_page_t m); 362 void vm_page_free_zero(vm_page_t m); 363 void vm_page_wakeup(vm_page_t m); 364 365 void vm_pageq_remove(vm_page_t m); 366 367 void vm_page_activate (vm_page_t); 368 vm_page_t vm_page_alloc (vm_object_t, vm_pindex_t, int); 369 vm_page_t vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, 370 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 371 vm_paddr_t boundary, vm_memattr_t memattr); 372 vm_page_t vm_page_alloc_freelist(int, int); 373 vm_page_t vm_page_grab (vm_object_t, vm_pindex_t, int); 374 void vm_page_cache(vm_page_t); 375 void vm_page_cache_free(vm_object_t, vm_pindex_t, vm_pindex_t); 376 void vm_page_cache_transfer(vm_object_t, vm_pindex_t, vm_object_t); 377 int vm_page_try_to_cache (vm_page_t); 378 int vm_page_try_to_free (vm_page_t); 379 void vm_page_dontneed(vm_page_t); 380 void vm_page_deactivate (vm_page_t); 381 vm_page_t vm_page_find_least(vm_object_t, vm_pindex_t); 382 vm_page_t vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr); 383 void vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr); 384 void vm_page_insert (vm_page_t, vm_object_t, vm_pindex_t); 385 boolean_t vm_page_is_cached(vm_object_t object, vm_pindex_t pindex); 386 vm_page_t vm_page_lookup (vm_object_t, vm_pindex_t); 387 vm_page_t vm_page_next(vm_page_t m); 388 int vm_page_pa_tryrelock(pmap_t, vm_paddr_t, vm_paddr_t *); 389 vm_page_t vm_page_prev(vm_page_t m); 390 void vm_page_putfake(vm_page_t m); 391 void vm_page_readahead_finish(vm_page_t m); 392 void vm_page_reference(vm_page_t m); 393 void vm_page_remove (vm_page_t); 394 void vm_page_rename (vm_page_t, vm_object_t, vm_pindex_t); 395 void vm_page_requeue(vm_page_t m); 396 void vm_page_set_valid_range(vm_page_t m, int base, int size); 397 void vm_page_sleep(vm_page_t m, const char *msg); 398 vm_page_t vm_page_splay(vm_pindex_t, vm_page_t); 399 vm_offset_t vm_page_startup(vm_offset_t vaddr); 400 void vm_page_unhold_pages(vm_page_t *ma, int count); 401 void vm_page_unwire (vm_page_t, int); 402 void vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr); 403 void vm_page_wire (vm_page_t); 404 void vm_page_set_validclean (vm_page_t, int, int); 405 void vm_page_clear_dirty (vm_page_t, int, int); 406 void vm_page_set_invalid (vm_page_t, int, int); 407 int vm_page_is_valid (vm_page_t, int, int); 408 void vm_page_test_dirty (vm_page_t); 409 vm_page_bits_t vm_page_bits(int base, int size); 410 void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid); 411 void vm_page_free_toq(vm_page_t m); 412 void vm_page_zero_idle_wakeup(void); 413 void vm_page_cowfault (vm_page_t); 414 int vm_page_cowsetup(vm_page_t); 415 void vm_page_cowclear (vm_page_t); 416 417 void vm_page_dirty_KBI(vm_page_t m); 418 void vm_page_lock_KBI(vm_page_t m, const char *file, int line); 419 void vm_page_unlock_KBI(vm_page_t m, const char *file, int line); 420 int vm_page_trylock_KBI(vm_page_t m, const char *file, int line); 421 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 422 void vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line); 423 #endif 424 425 #ifdef INVARIANTS 426 void vm_page_object_lock_assert(vm_page_t m); 427 #define VM_PAGE_OBJECT_LOCK_ASSERT(m) vm_page_object_lock_assert(m) 428 #else 429 #define VM_PAGE_OBJECT_LOCK_ASSERT(m) (void)0 430 #endif 431 432 /* 433 * We want to use atomic updates for the aflags field, which is 8 bits wide. 434 * However, not all architectures support atomic operations on 8-bit 435 * destinations. In order that we can easily use a 32-bit operation, we 436 * require that the aflags field be 32-bit aligned. 437 */ 438 CTASSERT(offsetof(struct vm_page, aflags) % sizeof(uint32_t) == 0); 439 440 /* 441 * Clear the given bits in the specified page. 442 */ 443 static inline void 444 vm_page_aflag_clear(vm_page_t m, uint8_t bits) 445 { 446 uint32_t *addr, val; 447 448 /* 449 * The PGA_REFERENCED flag can only be cleared if the object 450 * containing the page is locked. 451 */ 452 if ((bits & PGA_REFERENCED) != 0) 453 VM_PAGE_OBJECT_LOCK_ASSERT(m); 454 455 /* 456 * Access the whole 32-bit word containing the aflags field with an 457 * atomic update. Parallel non-atomic updates to the other fields 458 * within this word are handled properly by the atomic update. 459 */ 460 addr = (void *)&m->aflags; 461 KASSERT(((uintptr_t)addr & (sizeof(uint32_t) - 1)) == 0, 462 ("vm_page_aflag_clear: aflags is misaligned")); 463 val = bits; 464 #if BYTE_ORDER == BIG_ENDIAN 465 val <<= 24; 466 #endif 467 atomic_clear_32(addr, val); 468 } 469 470 /* 471 * Set the given bits in the specified page. 472 */ 473 static inline void 474 vm_page_aflag_set(vm_page_t m, uint8_t bits) 475 { 476 uint32_t *addr, val; 477 478 /* 479 * The PGA_WRITEABLE flag can only be set if the page is managed and 480 * VPO_BUSY. Currently, this flag is only set by pmap_enter(). 481 */ 482 KASSERT((bits & PGA_WRITEABLE) == 0 || 483 (m->oflags & (VPO_UNMANAGED | VPO_BUSY)) == VPO_BUSY, 484 ("vm_page_aflag_set: PGA_WRITEABLE and !VPO_BUSY")); 485 486 /* 487 * Access the whole 32-bit word containing the aflags field with an 488 * atomic update. Parallel non-atomic updates to the other fields 489 * within this word are handled properly by the atomic update. 490 */ 491 addr = (void *)&m->aflags; 492 KASSERT(((uintptr_t)addr & (sizeof(uint32_t) - 1)) == 0, 493 ("vm_page_aflag_set: aflags is misaligned")); 494 val = bits; 495 #if BYTE_ORDER == BIG_ENDIAN 496 val <<= 24; 497 #endif 498 atomic_set_32(addr, val); 499 } 500 501 /* 502 * vm_page_dirty: 503 * 504 * Set all bits in the page's dirty field. 505 * 506 * The object containing the specified page must be locked if the 507 * call is made from the machine-independent layer. 508 * 509 * See vm_page_clear_dirty_mask(). 510 */ 511 static __inline void 512 vm_page_dirty(vm_page_t m) 513 { 514 515 /* Use vm_page_dirty_KBI() under INVARIANTS to save memory. */ 516 #if defined(KLD_MODULE) || defined(INVARIANTS) 517 vm_page_dirty_KBI(m); 518 #else 519 m->dirty = VM_PAGE_BITS_ALL; 520 #endif 521 } 522 523 /* 524 * vm_page_sleep_if_busy: 525 * 526 * Sleep and release the page queues lock if VPO_BUSY is set or, 527 * if also_m_busy is TRUE, busy is non-zero. Returns TRUE if the 528 * thread slept and the page queues lock was released. 529 * Otherwise, retains the page queues lock and returns FALSE. 530 * 531 * The object containing the given page must be locked. 532 */ 533 static __inline int 534 vm_page_sleep_if_busy(vm_page_t m, int also_m_busy, const char *msg) 535 { 536 537 if ((m->oflags & VPO_BUSY) || (also_m_busy && m->busy)) { 538 vm_page_sleep(m, msg); 539 return (TRUE); 540 } 541 return (FALSE); 542 } 543 544 /* 545 * vm_page_undirty: 546 * 547 * Set page to not be dirty. Note: does not clear pmap modify bits 548 */ 549 static __inline void 550 vm_page_undirty(vm_page_t m) 551 { 552 553 VM_PAGE_OBJECT_LOCK_ASSERT(m); 554 m->dirty = 0; 555 } 556 557 #endif /* _KERNEL */ 558 #endif /* !_VM_PAGE_ */ 559