1 /*- 2 * SPDX-License-Identifier: (BSD-3-Clause AND MIT-CMU) 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * The Mach Operating System project at Carnegie-Mellon University. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * from: @(#)vm_page.h 8.2 (Berkeley) 12/13/93 35 * 36 * 37 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 38 * All rights reserved. 39 * 40 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 41 * 42 * Permission to use, copy, modify and distribute this software and 43 * its documentation is hereby granted, provided that both the copyright 44 * notice and this permission notice appear in all copies of the 45 * software, derivative works or modified versions, and any portions 46 * thereof, and that both notices appear in supporting documentation. 47 * 48 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 49 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 50 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 51 * 52 * Carnegie Mellon requests users of this software to return to 53 * 54 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 55 * School of Computer Science 56 * Carnegie Mellon University 57 * Pittsburgh PA 15213-3890 58 * 59 * any improvements or extensions that they make and grant Carnegie the 60 * rights to redistribute these changes. 61 * 62 * $FreeBSD$ 63 */ 64 65 /* 66 * Resident memory system definitions. 67 */ 68 69 #ifndef _VM_PAGE_ 70 #define _VM_PAGE_ 71 72 #include <vm/pmap.h> 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 collections: 80 * 81 * A radix tree 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 * In general, operations on this structure's mutable fields are 95 * synchronized using either one of or a combination of the lock on the 96 * object that the page belongs to (O), the page lock (P), 97 * the per-domain lock for the free queues (F), or the page's queue 98 * lock (Q). The physical address of a page is used to select its page 99 * lock from a pool. The queue lock for a page depends on the value of 100 * its queue field and described in detail below. If a field is 101 * annotated below with two of these locks, then holding either lock is 102 * sufficient for read access, but both locks are required for write 103 * access. An annotation of (C) indicates that the field is immutable. 104 * 105 * In contrast, the synchronization of accesses to the page's 106 * dirty field is machine dependent (M). In the 107 * machine-independent layer, the lock on the object that the 108 * page belongs to must be held in order to operate on the field. 109 * However, the pmap layer is permitted to set all bits within 110 * the field without holding that lock. If the underlying 111 * architecture does not support atomic read-modify-write 112 * operations on the field's type, then the machine-independent 113 * layer uses a 32-bit atomic on the aligned 32-bit word that 114 * contains the dirty field. In the machine-independent layer, 115 * the implementation of read-modify-write operations on the 116 * field is encapsulated in vm_page_clear_dirty_mask(). 117 * 118 * The page structure contains two counters which prevent page reuse. 119 * Both counters are protected by the page lock (P). The hold 120 * counter counts transient references obtained via a pmap lookup, and 121 * is also used to prevent page reclamation in situations where it is 122 * undesirable to block other accesses to the page. The wire counter 123 * is used to implement mlock(2) and is non-zero for pages containing 124 * kernel memory. Pages that are wired or held will not be reclaimed 125 * or laundered by the page daemon, but are treated differently during 126 * a page queue scan: held pages remain at their position in the queue, 127 * while wired pages are removed from the queue and must later be 128 * re-enqueued appropriately by the unwiring thread. It is legal to 129 * call vm_page_free() on a held page; doing so causes it to be removed 130 * from its object and page queue, and the page is released to the 131 * allocator once the last hold reference is dropped. In contrast, 132 * wired pages may not be freed. 133 * 134 * In some pmap implementations, the wire count of a page table page is 135 * used to track the number of populated entries. 136 * 137 * The busy lock is an embedded reader-writer lock which protects the 138 * page's contents and identity (i.e., its <object, pindex> tuple) and 139 * interlocks with the object lock (O). In particular, a page may be 140 * busied or unbusied only with the object write lock held. To avoid 141 * bloating the page structure, the busy lock lacks some of the 142 * features available to the kernel's general-purpose synchronization 143 * primitives. As a result, busy lock ordering rules are not verified, 144 * lock recursion is not detected, and an attempt to xbusy a busy page 145 * or sbusy an xbusy page results will trigger a panic rather than 146 * causing the thread to block. vm_page_sleep_if_busy() can be used to 147 * sleep until the page's busy state changes, after which the caller 148 * must re-lookup the page and re-evaluate its state. 149 * 150 * The queue field is the index of the page queue containing the page, 151 * or PQ_NONE if the page is not enqueued. The queue lock of a page is 152 * the page queue lock corresponding to the page queue index, or the 153 * page lock (P) for the page if it is not enqueued. To modify the 154 * queue field, the queue lock for the old value of the field must be 155 * held. There is one exception to this rule: the page daemon may 156 * transition the queue field from PQ_INACTIVE to PQ_NONE immediately 157 * prior to freeing a page during an inactive queue scan. At that 158 * point the page has already been physically dequeued and no other 159 * references to that vm_page structure exist. 160 * 161 * To avoid contention on page queue locks, page queue operations 162 * (enqueue, dequeue, requeue) are batched using per-CPU queues. A 163 * deferred operation is requested by inserting an entry into a batch 164 * queue; the entry is simply a pointer to the page, and the request 165 * type is encoded in the page's aflags field using the values in 166 * PGA_QUEUE_STATE_MASK. The type-stability of struct vm_pages is 167 * crucial to this scheme since the processing of entries in a given 168 * batch queue may be deferred indefinitely. In particular, a page may 169 * be freed before its pending batch queue entries have been processed. 170 * The page lock (P) must be held to schedule a batched queue 171 * operation, and the page queue lock must be held in order to process 172 * batch queue entries for the page queue. There is one exception to 173 * this rule: the thread freeing a page may schedule a dequeue without 174 * holding the page lock. In this scenario the only other thread which 175 * may hold a reference to the page is the page daemon, which is 176 * careful to avoid modifying the page's queue state once the dequeue 177 * has been requested by setting PGA_DEQUEUE. 178 */ 179 180 #if PAGE_SIZE == 4096 181 #define VM_PAGE_BITS_ALL 0xffu 182 typedef uint8_t vm_page_bits_t; 183 #elif PAGE_SIZE == 8192 184 #define VM_PAGE_BITS_ALL 0xffffu 185 typedef uint16_t vm_page_bits_t; 186 #elif PAGE_SIZE == 16384 187 #define VM_PAGE_BITS_ALL 0xffffffffu 188 typedef uint32_t vm_page_bits_t; 189 #elif PAGE_SIZE == 32768 190 #define VM_PAGE_BITS_ALL 0xfffffffffffffffflu 191 typedef uint64_t vm_page_bits_t; 192 #endif 193 194 struct vm_page { 195 union { 196 TAILQ_ENTRY(vm_page) q; /* page queue or free list (Q) */ 197 struct { 198 SLIST_ENTRY(vm_page) ss; /* private slists */ 199 void *pv; 200 } s; 201 struct { 202 u_long p; 203 u_long v; 204 } memguard; 205 } plinks; 206 TAILQ_ENTRY(vm_page) listq; /* pages in same object (O) */ 207 vm_object_t object; /* which object am I in (O,P) */ 208 vm_pindex_t pindex; /* offset into object (O,P) */ 209 vm_paddr_t phys_addr; /* physical address of page (C) */ 210 struct md_page md; /* machine dependent stuff */ 211 u_int wire_count; /* wired down maps refs (P) */ 212 volatile u_int busy_lock; /* busy owners lock */ 213 uint16_t flags; /* page PG_* flags (P) */ 214 uint8_t order; /* index of the buddy queue (F) */ 215 uint8_t pool; /* vm_phys freepool index (F) */ 216 uint8_t aflags; /* access is atomic */ 217 uint8_t oflags; /* page VPO_* flags (O) */ 218 uint8_t queue; /* page queue index (Q) */ 219 int8_t psind; /* pagesizes[] index (O) */ 220 int8_t segind; /* vm_phys segment index (C) */ 221 u_char act_count; /* page usage count (P) */ 222 /* NOTE that these must support one bit per DEV_BSIZE in a page */ 223 /* so, on normal X86 kernels, they must be at least 8 bits wide */ 224 vm_page_bits_t valid; /* map of valid DEV_BSIZE chunks (O) */ 225 vm_page_bits_t dirty; /* map of dirty DEV_BSIZE chunks (M) */ 226 }; 227 228 /* 229 * Page flags stored in oflags: 230 * 231 * Access to these page flags is synchronized by the lock on the object 232 * containing the page (O). 233 * 234 * Note: VPO_UNMANAGED (used by OBJT_DEVICE, OBJT_PHYS and OBJT_SG) 235 * indicates that the page is not under PV management but 236 * otherwise should be treated as a normal page. Pages not 237 * under PV management cannot be paged out via the 238 * object/vm_page_t because there is no knowledge of their pte 239 * mappings, and such pages are also not on any PQ queue. 240 * 241 */ 242 #define VPO_KMEM_EXEC 0x01 /* kmem mapping allows execution */ 243 #define VPO_SWAPSLEEP 0x02 /* waiting for swap to finish */ 244 #define VPO_UNMANAGED 0x04 /* no PV management for page */ 245 #define VPO_SWAPINPROG 0x08 /* swap I/O in progress on page */ 246 #define VPO_NOSYNC 0x10 /* do not collect for syncer */ 247 248 /* 249 * Busy page implementation details. 250 * The algorithm is taken mostly by rwlock(9) and sx(9) locks implementation, 251 * even if the support for owner identity is removed because of size 252 * constraints. Checks on lock recursion are then not possible, while the 253 * lock assertions effectiveness is someway reduced. 254 */ 255 #define VPB_BIT_SHARED 0x01 256 #define VPB_BIT_EXCLUSIVE 0x02 257 #define VPB_BIT_WAITERS 0x04 258 #define VPB_BIT_FLAGMASK \ 259 (VPB_BIT_SHARED | VPB_BIT_EXCLUSIVE | VPB_BIT_WAITERS) 260 261 #define VPB_SHARERS_SHIFT 3 262 #define VPB_SHARERS(x) \ 263 (((x) & ~VPB_BIT_FLAGMASK) >> VPB_SHARERS_SHIFT) 264 #define VPB_SHARERS_WORD(x) ((x) << VPB_SHARERS_SHIFT | VPB_BIT_SHARED) 265 #define VPB_ONE_SHARER (1 << VPB_SHARERS_SHIFT) 266 267 #define VPB_SINGLE_EXCLUSIVER VPB_BIT_EXCLUSIVE 268 269 #define VPB_UNBUSIED VPB_SHARERS_WORD(0) 270 271 #define PQ_NONE 255 272 #define PQ_INACTIVE 0 273 #define PQ_ACTIVE 1 274 #define PQ_LAUNDRY 2 275 #define PQ_UNSWAPPABLE 3 276 #define PQ_COUNT 4 277 278 #ifndef VM_PAGE_HAVE_PGLIST 279 TAILQ_HEAD(pglist, vm_page); 280 #define VM_PAGE_HAVE_PGLIST 281 #endif 282 SLIST_HEAD(spglist, vm_page); 283 284 #ifdef _KERNEL 285 extern vm_page_t bogus_page; 286 #endif /* _KERNEL */ 287 288 extern struct mtx_padalign pa_lock[]; 289 290 #if defined(__arm__) 291 #define PDRSHIFT PDR_SHIFT 292 #elif !defined(PDRSHIFT) 293 #define PDRSHIFT 21 294 #endif 295 296 #define pa_index(pa) ((pa) >> PDRSHIFT) 297 #define PA_LOCKPTR(pa) ((struct mtx *)(&pa_lock[pa_index(pa) % PA_LOCK_COUNT])) 298 #define PA_LOCKOBJPTR(pa) ((struct lock_object *)PA_LOCKPTR((pa))) 299 #define PA_LOCK(pa) mtx_lock(PA_LOCKPTR(pa)) 300 #define PA_TRYLOCK(pa) mtx_trylock(PA_LOCKPTR(pa)) 301 #define PA_UNLOCK(pa) mtx_unlock(PA_LOCKPTR(pa)) 302 #define PA_UNLOCK_COND(pa) \ 303 do { \ 304 if ((pa) != 0) { \ 305 PA_UNLOCK((pa)); \ 306 (pa) = 0; \ 307 } \ 308 } while (0) 309 310 #define PA_LOCK_ASSERT(pa, a) mtx_assert(PA_LOCKPTR(pa), (a)) 311 312 #if defined(KLD_MODULE) && !defined(KLD_TIED) 313 #define vm_page_lock(m) vm_page_lock_KBI((m), LOCK_FILE, LOCK_LINE) 314 #define vm_page_unlock(m) vm_page_unlock_KBI((m), LOCK_FILE, LOCK_LINE) 315 #define vm_page_trylock(m) vm_page_trylock_KBI((m), LOCK_FILE, LOCK_LINE) 316 #else /* !KLD_MODULE */ 317 #define vm_page_lockptr(m) (PA_LOCKPTR(VM_PAGE_TO_PHYS((m)))) 318 #define vm_page_lock(m) mtx_lock(vm_page_lockptr((m))) 319 #define vm_page_unlock(m) mtx_unlock(vm_page_lockptr((m))) 320 #define vm_page_trylock(m) mtx_trylock(vm_page_lockptr((m))) 321 #endif 322 #if defined(INVARIANTS) 323 #define vm_page_assert_locked(m) \ 324 vm_page_assert_locked_KBI((m), __FILE__, __LINE__) 325 #define vm_page_lock_assert(m, a) \ 326 vm_page_lock_assert_KBI((m), (a), __FILE__, __LINE__) 327 #else 328 #define vm_page_assert_locked(m) 329 #define vm_page_lock_assert(m, a) 330 #endif 331 332 /* 333 * The vm_page's aflags are updated using atomic operations. To set or clear 334 * these flags, the functions vm_page_aflag_set() and vm_page_aflag_clear() 335 * must be used. Neither these flags nor these functions are part of the KBI. 336 * 337 * PGA_REFERENCED may be cleared only if the page is locked. It is set by 338 * both the MI and MD VM layers. However, kernel loadable modules should not 339 * directly set this flag. They should call vm_page_reference() instead. 340 * 341 * PGA_WRITEABLE is set exclusively on managed pages by pmap_enter(). 342 * When it does so, the object must be locked, or the page must be 343 * exclusive busied. The MI VM layer must never access this flag 344 * directly. Instead, it should call pmap_page_is_write_mapped(). 345 * 346 * PGA_EXECUTABLE may be set by pmap routines, and indicates that a page has 347 * at least one executable mapping. It is not consumed by the MI VM layer. 348 * 349 * PGA_ENQUEUED is set and cleared when a page is inserted into or removed 350 * from a page queue, respectively. It determines whether the plinks.q field 351 * of the page is valid. To set or clear this flag, the queue lock for the 352 * page must be held: the page queue lock corresponding to the page's "queue" 353 * field if its value is not PQ_NONE, and the page lock otherwise. 354 * 355 * PGA_DEQUEUE is set when the page is scheduled to be dequeued from a page 356 * queue, and cleared when the dequeue request is processed. A page may 357 * have PGA_DEQUEUE set and PGA_ENQUEUED cleared, for instance if a dequeue 358 * is requested after the page is scheduled to be enqueued but before it is 359 * actually inserted into the page queue. For allocated pages, the page lock 360 * must be held to set this flag, but it may be set by vm_page_free_prep() 361 * without the page lock held. The page queue lock must be held to clear the 362 * PGA_DEQUEUE flag. 363 * 364 * PGA_REQUEUE is set when the page is scheduled to be enqueued or requeued 365 * in its page queue. The page lock must be held to set this flag, and the 366 * queue lock for the page must be held to clear it. 367 * 368 * PGA_REQUEUE_HEAD is a special flag for enqueuing pages near the head of 369 * the inactive queue, thus bypassing LRU. The page lock must be held to 370 * set this flag, and the queue lock for the page must be held to clear it. 371 */ 372 #define PGA_WRITEABLE 0x01 /* page may be mapped writeable */ 373 #define PGA_REFERENCED 0x02 /* page has been referenced */ 374 #define PGA_EXECUTABLE 0x04 /* page may be mapped executable */ 375 #define PGA_ENQUEUED 0x08 /* page is enqueued in a page queue */ 376 #define PGA_DEQUEUE 0x10 /* page is due to be dequeued */ 377 #define PGA_REQUEUE 0x20 /* page is due to be requeued */ 378 #define PGA_REQUEUE_HEAD 0x40 /* page requeue should bypass LRU */ 379 380 #define PGA_QUEUE_STATE_MASK (PGA_ENQUEUED | PGA_DEQUEUE | PGA_REQUEUE | \ 381 PGA_REQUEUE_HEAD) 382 383 /* 384 * Page flags. If changed at any other time than page allocation or 385 * freeing, the modification must be protected by the vm_page lock. 386 * 387 * The PG_PCPU_CACHE flag is set at allocation time if the page was 388 * allocated from a per-CPU cache. It is cleared the next time that the 389 * page is allocated from the physical memory allocator. 390 */ 391 #define PG_PCPU_CACHE 0x0001 /* was allocated from per-CPU caches */ 392 #define PG_FICTITIOUS 0x0004 /* physical page doesn't exist */ 393 #define PG_ZERO 0x0008 /* page is zeroed */ 394 #define PG_MARKER 0x0010 /* special queue marker page */ 395 #define PG_NODUMP 0x0080 /* don't include this page in a dump */ 396 397 /* 398 * Misc constants. 399 */ 400 #define ACT_DECLINE 1 401 #define ACT_ADVANCE 3 402 #define ACT_INIT 5 403 #define ACT_MAX 64 404 405 #ifdef _KERNEL 406 407 #include <sys/systm.h> 408 409 #include <machine/atomic.h> 410 411 /* 412 * Each pageable resident page falls into one of five lists: 413 * 414 * free 415 * Available for allocation now. 416 * 417 * inactive 418 * Low activity, candidates for reclamation. 419 * This list is approximately LRU ordered. 420 * 421 * laundry 422 * This is the list of pages that should be 423 * paged out next. 424 * 425 * unswappable 426 * Dirty anonymous pages that cannot be paged 427 * out because no swap device is configured. 428 * 429 * active 430 * Pages that are "active", i.e., they have been 431 * recently referenced. 432 * 433 */ 434 435 extern vm_page_t vm_page_array; /* First resident page in table */ 436 extern long vm_page_array_size; /* number of vm_page_t's */ 437 extern long first_page; /* first physical page number */ 438 439 #define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr) 440 441 /* 442 * PHYS_TO_VM_PAGE() returns the vm_page_t object that represents a memory 443 * page to which the given physical address belongs. The correct vm_page_t 444 * object is returned for addresses that are not page-aligned. 445 */ 446 vm_page_t PHYS_TO_VM_PAGE(vm_paddr_t pa); 447 448 /* 449 * Page allocation parameters for vm_page for the functions 450 * vm_page_alloc(), vm_page_grab(), vm_page_alloc_contig() and 451 * vm_page_alloc_freelist(). Some functions support only a subset 452 * of the flags, and ignore others, see the flags legend. 453 * 454 * The meaning of VM_ALLOC_ZERO differs slightly between the vm_page_alloc*() 455 * and the vm_page_grab*() functions. See these functions for details. 456 * 457 * Bits 0 - 1 define class. 458 * Bits 2 - 15 dedicated for flags. 459 * Legend: 460 * (a) - vm_page_alloc() supports the flag. 461 * (c) - vm_page_alloc_contig() supports the flag. 462 * (f) - vm_page_alloc_freelist() supports the flag. 463 * (g) - vm_page_grab() supports the flag. 464 * (p) - vm_page_grab_pages() supports the flag. 465 * Bits above 15 define the count of additional pages that the caller 466 * intends to allocate. 467 */ 468 #define VM_ALLOC_NORMAL 0 469 #define VM_ALLOC_INTERRUPT 1 470 #define VM_ALLOC_SYSTEM 2 471 #define VM_ALLOC_CLASS_MASK 3 472 #define VM_ALLOC_WAITOK 0x0008 /* (acf) Sleep and retry */ 473 #define VM_ALLOC_WAITFAIL 0x0010 /* (acf) Sleep and return error */ 474 #define VM_ALLOC_WIRED 0x0020 /* (acfgp) Allocate a wired page */ 475 #define VM_ALLOC_ZERO 0x0040 /* (acfgp) Allocate a prezeroed page */ 476 #define VM_ALLOC_NOOBJ 0x0100 /* (acg) No associated object */ 477 #define VM_ALLOC_NOBUSY 0x0200 /* (acgp) Do not excl busy the page */ 478 #define VM_ALLOC_IGN_SBUSY 0x1000 /* (gp) Ignore shared busy flag */ 479 #define VM_ALLOC_NODUMP 0x2000 /* (ag) don't include in dump */ 480 #define VM_ALLOC_SBUSY 0x4000 /* (acgp) Shared busy the page */ 481 #define VM_ALLOC_NOWAIT 0x8000 /* (acfgp) Do not sleep */ 482 #define VM_ALLOC_COUNT_SHIFT 16 483 #define VM_ALLOC_COUNT(count) ((count) << VM_ALLOC_COUNT_SHIFT) 484 485 #ifdef M_NOWAIT 486 static inline int 487 malloc2vm_flags(int malloc_flags) 488 { 489 int pflags; 490 491 KASSERT((malloc_flags & M_USE_RESERVE) == 0 || 492 (malloc_flags & M_NOWAIT) != 0, 493 ("M_USE_RESERVE requires M_NOWAIT")); 494 pflags = (malloc_flags & M_USE_RESERVE) != 0 ? VM_ALLOC_INTERRUPT : 495 VM_ALLOC_SYSTEM; 496 if ((malloc_flags & M_ZERO) != 0) 497 pflags |= VM_ALLOC_ZERO; 498 if ((malloc_flags & M_NODUMP) != 0) 499 pflags |= VM_ALLOC_NODUMP; 500 if ((malloc_flags & M_NOWAIT)) 501 pflags |= VM_ALLOC_NOWAIT; 502 if ((malloc_flags & M_WAITOK)) 503 pflags |= VM_ALLOC_WAITOK; 504 return (pflags); 505 } 506 #endif 507 508 /* 509 * Predicates supported by vm_page_ps_test(): 510 * 511 * PS_ALL_DIRTY is true only if the entire (super)page is dirty. 512 * However, it can be spuriously false when the (super)page has become 513 * dirty in the pmap but that information has not been propagated to the 514 * machine-independent layer. 515 */ 516 #define PS_ALL_DIRTY 0x1 517 #define PS_ALL_VALID 0x2 518 #define PS_NONE_BUSY 0x4 519 520 void vm_page_busy_downgrade(vm_page_t m); 521 void vm_page_busy_sleep(vm_page_t m, const char *msg, bool nonshared); 522 void vm_page_flash(vm_page_t m); 523 void vm_page_free(vm_page_t m); 524 void vm_page_free_zero(vm_page_t m); 525 526 void vm_page_activate (vm_page_t); 527 void vm_page_advise(vm_page_t m, int advice); 528 vm_page_t vm_page_alloc(vm_object_t, vm_pindex_t, int); 529 vm_page_t vm_page_alloc_domain(vm_object_t, vm_pindex_t, int, int); 530 vm_page_t vm_page_alloc_after(vm_object_t, vm_pindex_t, int, vm_page_t); 531 vm_page_t vm_page_alloc_domain_after(vm_object_t, vm_pindex_t, int, int, 532 vm_page_t); 533 vm_page_t vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, 534 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 535 vm_paddr_t boundary, vm_memattr_t memattr); 536 vm_page_t vm_page_alloc_contig_domain(vm_object_t object, 537 vm_pindex_t pindex, int domain, int req, u_long npages, vm_paddr_t low, 538 vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 539 vm_memattr_t memattr); 540 vm_page_t vm_page_alloc_freelist(int, int); 541 vm_page_t vm_page_alloc_freelist_domain(int, int, int); 542 bool vm_page_blacklist_add(vm_paddr_t pa, bool verbose); 543 void vm_page_change_lock(vm_page_t m, struct mtx **mtx); 544 vm_page_t vm_page_grab (vm_object_t, vm_pindex_t, int); 545 int vm_page_grab_pages(vm_object_t object, vm_pindex_t pindex, int allocflags, 546 vm_page_t *ma, int count); 547 void vm_page_deactivate(vm_page_t); 548 void vm_page_deactivate_noreuse(vm_page_t); 549 void vm_page_dequeue(vm_page_t m); 550 void vm_page_dequeue_deferred(vm_page_t m); 551 vm_page_t vm_page_find_least(vm_object_t, vm_pindex_t); 552 bool vm_page_free_prep(vm_page_t m); 553 vm_page_t vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr); 554 void vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr); 555 int vm_page_insert (vm_page_t, vm_object_t, vm_pindex_t); 556 void vm_page_launder(vm_page_t m); 557 vm_page_t vm_page_lookup (vm_object_t, vm_pindex_t); 558 vm_page_t vm_page_next(vm_page_t m); 559 int vm_page_pa_tryrelock(pmap_t, vm_paddr_t, vm_paddr_t *); 560 void vm_page_pqbatch_drain(void); 561 void vm_page_pqbatch_submit(vm_page_t m, uint8_t queue); 562 vm_page_t vm_page_prev(vm_page_t m); 563 bool vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m); 564 void vm_page_putfake(vm_page_t m); 565 void vm_page_readahead_finish(vm_page_t m); 566 bool vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, 567 vm_paddr_t high, u_long alignment, vm_paddr_t boundary); 568 bool vm_page_reclaim_contig_domain(int domain, int req, u_long npages, 569 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary); 570 void vm_page_reference(vm_page_t m); 571 #define VPR_TRYFREE 0x01 572 #define VPR_NOREUSE 0x02 573 void vm_page_release(vm_page_t m, int flags); 574 void vm_page_release_locked(vm_page_t m, int flags); 575 bool vm_page_remove(vm_page_t); 576 int vm_page_rename(vm_page_t, vm_object_t, vm_pindex_t); 577 vm_page_t vm_page_replace(vm_page_t mnew, vm_object_t object, 578 vm_pindex_t pindex); 579 void vm_page_requeue(vm_page_t m); 580 int vm_page_sbusied(vm_page_t m); 581 vm_page_t vm_page_scan_contig(u_long npages, vm_page_t m_start, 582 vm_page_t m_end, u_long alignment, vm_paddr_t boundary, int options); 583 void vm_page_set_valid_range(vm_page_t m, int base, int size); 584 int vm_page_sleep_if_busy(vm_page_t m, const char *msg); 585 vm_offset_t vm_page_startup(vm_offset_t vaddr); 586 void vm_page_sunbusy(vm_page_t m); 587 void vm_page_swapqueue(vm_page_t m, uint8_t oldq, uint8_t newq); 588 int vm_page_trysbusy(vm_page_t m); 589 void vm_page_unhold_pages(vm_page_t *ma, int count); 590 void vm_page_unswappable(vm_page_t m); 591 bool vm_page_unwire(vm_page_t m, uint8_t queue); 592 bool vm_page_unwire_noq(vm_page_t m); 593 void vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr); 594 void vm_page_wire (vm_page_t); 595 void vm_page_xunbusy_hard(vm_page_t m); 596 void vm_page_xunbusy_maybelocked(vm_page_t m); 597 void vm_page_set_validclean (vm_page_t, int, int); 598 void vm_page_clear_dirty (vm_page_t, int, int); 599 void vm_page_set_invalid (vm_page_t, int, int); 600 int vm_page_is_valid (vm_page_t, int, int); 601 void vm_page_test_dirty (vm_page_t); 602 vm_page_bits_t vm_page_bits(int base, int size); 603 void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid); 604 void vm_page_free_toq(vm_page_t m); 605 void vm_page_free_pages_toq(struct spglist *free, bool update_wire_count); 606 607 void vm_page_dirty_KBI(vm_page_t m); 608 void vm_page_lock_KBI(vm_page_t m, const char *file, int line); 609 void vm_page_unlock_KBI(vm_page_t m, const char *file, int line); 610 int vm_page_trylock_KBI(vm_page_t m, const char *file, int line); 611 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 612 void vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line); 613 void vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line); 614 #endif 615 616 #define vm_page_assert_sbusied(m) \ 617 KASSERT(vm_page_sbusied(m), \ 618 ("vm_page_assert_sbusied: page %p not shared busy @ %s:%d", \ 619 (m), __FILE__, __LINE__)) 620 621 #define vm_page_assert_unbusied(m) \ 622 KASSERT(!vm_page_busied(m), \ 623 ("vm_page_assert_unbusied: page %p busy @ %s:%d", \ 624 (m), __FILE__, __LINE__)) 625 626 #define vm_page_assert_xbusied(m) \ 627 KASSERT(vm_page_xbusied(m), \ 628 ("vm_page_assert_xbusied: page %p not exclusive busy @ %s:%d", \ 629 (m), __FILE__, __LINE__)) 630 631 #define vm_page_busied(m) \ 632 ((m)->busy_lock != VPB_UNBUSIED) 633 634 #define vm_page_sbusy(m) do { \ 635 if (!vm_page_trysbusy(m)) \ 636 panic("%s: page %p failed shared busying", __func__, \ 637 (m)); \ 638 } while (0) 639 640 #define vm_page_tryxbusy(m) \ 641 (atomic_cmpset_acq_int(&(m)->busy_lock, VPB_UNBUSIED, \ 642 VPB_SINGLE_EXCLUSIVER)) 643 644 #define vm_page_xbusied(m) \ 645 (((m)->busy_lock & VPB_SINGLE_EXCLUSIVER) != 0) 646 647 #define vm_page_xbusy(m) do { \ 648 if (!vm_page_tryxbusy(m)) \ 649 panic("%s: page %p failed exclusive busying", __func__, \ 650 (m)); \ 651 } while (0) 652 653 /* Note: page m's lock must not be owned by the caller. */ 654 #define vm_page_xunbusy(m) do { \ 655 if (!atomic_cmpset_rel_int(&(m)->busy_lock, \ 656 VPB_SINGLE_EXCLUSIVER, VPB_UNBUSIED)) \ 657 vm_page_xunbusy_hard(m); \ 658 } while (0) 659 660 #ifdef INVARIANTS 661 void vm_page_object_lock_assert(vm_page_t m); 662 #define VM_PAGE_OBJECT_LOCK_ASSERT(m) vm_page_object_lock_assert(m) 663 void vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits); 664 #define VM_PAGE_ASSERT_PGA_WRITEABLE(m, bits) \ 665 vm_page_assert_pga_writeable(m, bits) 666 #else 667 #define VM_PAGE_OBJECT_LOCK_ASSERT(m) (void)0 668 #define VM_PAGE_ASSERT_PGA_WRITEABLE(m, bits) (void)0 669 #endif 670 671 /* 672 * We want to use atomic updates for the aflags field, which is 8 bits wide. 673 * However, not all architectures support atomic operations on 8-bit 674 * destinations. In order that we can easily use a 32-bit operation, we 675 * require that the aflags field be 32-bit aligned. 676 */ 677 _Static_assert(offsetof(struct vm_page, aflags) % sizeof(uint32_t) == 0, 678 "aflags field is not 32-bit aligned"); 679 680 /* 681 * We want to be able to update the aflags and queue fields atomically in 682 * the same operation. 683 */ 684 _Static_assert(offsetof(struct vm_page, aflags) / sizeof(uint32_t) == 685 offsetof(struct vm_page, queue) / sizeof(uint32_t), 686 "aflags and queue fields do not belong to the same 32-bit word"); 687 _Static_assert(offsetof(struct vm_page, queue) % sizeof(uint32_t) == 2, 688 "queue field is at an unexpected offset"); 689 _Static_assert(sizeof(((struct vm_page *)NULL)->queue) == 1, 690 "queue field has an unexpected size"); 691 692 #if BYTE_ORDER == LITTLE_ENDIAN 693 #define VM_PAGE_AFLAG_SHIFT 0 694 #define VM_PAGE_QUEUE_SHIFT 16 695 #else 696 #define VM_PAGE_AFLAG_SHIFT 24 697 #define VM_PAGE_QUEUE_SHIFT 8 698 #endif 699 #define VM_PAGE_QUEUE_MASK (0xff << VM_PAGE_QUEUE_SHIFT) 700 701 /* 702 * Clear the given bits in the specified page. 703 */ 704 static inline void 705 vm_page_aflag_clear(vm_page_t m, uint8_t bits) 706 { 707 uint32_t *addr, val; 708 709 /* 710 * The PGA_REFERENCED flag can only be cleared if the page is locked. 711 */ 712 if ((bits & PGA_REFERENCED) != 0) 713 vm_page_assert_locked(m); 714 715 /* 716 * Access the whole 32-bit word containing the aflags field with an 717 * atomic update. Parallel non-atomic updates to the other fields 718 * within this word are handled properly by the atomic update. 719 */ 720 addr = (void *)&m->aflags; 721 val = bits << VM_PAGE_AFLAG_SHIFT; 722 atomic_clear_32(addr, val); 723 } 724 725 /* 726 * Set the given bits in the specified page. 727 */ 728 static inline void 729 vm_page_aflag_set(vm_page_t m, uint8_t bits) 730 { 731 uint32_t *addr, val; 732 733 VM_PAGE_ASSERT_PGA_WRITEABLE(m, bits); 734 735 /* 736 * Access the whole 32-bit word containing the aflags field with an 737 * atomic update. Parallel non-atomic updates to the other fields 738 * within this word are handled properly by the atomic update. 739 */ 740 addr = (void *)&m->aflags; 741 val = bits << VM_PAGE_AFLAG_SHIFT; 742 atomic_set_32(addr, val); 743 } 744 745 /* 746 * Atomically update the queue state of the page. The operation fails if 747 * any of the queue flags in "fflags" are set or if the "queue" field of 748 * the page does not match the expected value; if the operation is 749 * successful, the flags in "nflags" are set and all other queue state 750 * flags are cleared. 751 */ 752 static inline bool 753 vm_page_pqstate_cmpset(vm_page_t m, uint32_t oldq, uint32_t newq, 754 uint32_t fflags, uint32_t nflags) 755 { 756 uint32_t *addr, nval, oval, qsmask; 757 758 vm_page_assert_locked(m); 759 760 fflags <<= VM_PAGE_AFLAG_SHIFT; 761 nflags <<= VM_PAGE_AFLAG_SHIFT; 762 newq <<= VM_PAGE_QUEUE_SHIFT; 763 oldq <<= VM_PAGE_QUEUE_SHIFT; 764 qsmask = ((PGA_DEQUEUE | PGA_REQUEUE | PGA_REQUEUE_HEAD) << 765 VM_PAGE_AFLAG_SHIFT) | VM_PAGE_QUEUE_MASK; 766 767 addr = (void *)&m->aflags; 768 oval = atomic_load_32(addr); 769 do { 770 if ((oval & fflags) != 0) 771 return (false); 772 if ((oval & VM_PAGE_QUEUE_MASK) != oldq) 773 return (false); 774 nval = (oval & ~qsmask) | nflags | newq; 775 } while (!atomic_fcmpset_32(addr, &oval, nval)); 776 777 return (true); 778 } 779 780 /* 781 * vm_page_dirty: 782 * 783 * Set all bits in the page's dirty field. 784 * 785 * The object containing the specified page must be locked if the 786 * call is made from the machine-independent layer. 787 * 788 * See vm_page_clear_dirty_mask(). 789 */ 790 static __inline void 791 vm_page_dirty(vm_page_t m) 792 { 793 794 /* Use vm_page_dirty_KBI() under INVARIANTS to save memory. */ 795 #if (defined(KLD_MODULE) && !defined(KLD_TIED)) || defined(INVARIANTS) 796 vm_page_dirty_KBI(m); 797 #else 798 m->dirty = VM_PAGE_BITS_ALL; 799 #endif 800 } 801 802 /* 803 * vm_page_undirty: 804 * 805 * Set page to not be dirty. Note: does not clear pmap modify bits 806 */ 807 static __inline void 808 vm_page_undirty(vm_page_t m) 809 { 810 811 VM_PAGE_OBJECT_LOCK_ASSERT(m); 812 m->dirty = 0; 813 } 814 815 static inline void 816 vm_page_replace_checked(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex, 817 vm_page_t mold) 818 { 819 vm_page_t mret; 820 821 mret = vm_page_replace(mnew, object, pindex); 822 KASSERT(mret == mold, 823 ("invalid page replacement, mold=%p, mret=%p", mold, mret)); 824 825 /* Unused if !INVARIANTS. */ 826 (void)mold; 827 (void)mret; 828 } 829 830 /* 831 * vm_page_queue: 832 * 833 * Return the index of the queue containing m. This index is guaranteed 834 * not to change while the page lock is held. 835 */ 836 static inline uint8_t 837 vm_page_queue(vm_page_t m) 838 { 839 840 vm_page_assert_locked(m); 841 842 if ((m->aflags & PGA_DEQUEUE) != 0) 843 return (PQ_NONE); 844 atomic_thread_fence_acq(); 845 return (m->queue); 846 } 847 848 static inline bool 849 vm_page_active(vm_page_t m) 850 { 851 852 return (vm_page_queue(m) == PQ_ACTIVE); 853 } 854 855 static inline bool 856 vm_page_inactive(vm_page_t m) 857 { 858 859 return (vm_page_queue(m) == PQ_INACTIVE); 860 } 861 862 static inline bool 863 vm_page_in_laundry(vm_page_t m) 864 { 865 uint8_t queue; 866 867 queue = vm_page_queue(m); 868 return (queue == PQ_LAUNDRY || queue == PQ_UNSWAPPABLE); 869 } 870 871 /* 872 * vm_page_wired: 873 * 874 * Return true if a reference prevents the page from being reclaimable. 875 */ 876 static inline bool 877 vm_page_wired(vm_page_t m) 878 { 879 880 return (m->wire_count > 0); 881 } 882 883 #endif /* _KERNEL */ 884 #endif /* !_VM_PAGE_ */ 885