2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * The Mach Operating System project at Carnegie-Mellon University.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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
32 * from: @(#)vm_page.h 8.2 (Berkeley) 12/13/93
35 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
36 * All rights reserved.
38 * Authors: Avadis Tevanian, Jr., Michael Wayne Young
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.
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.
50 * Carnegie Mellon requests users of this software to return to
52 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
53 * School of Computer Science
54 * Carnegie Mellon University
55 * Pittsburgh PA 15213-3890
57 * any improvements or extensions that they make and grant Carnegie the
58 * rights to redistribute these changes.
64 * Resident memory system definitions.
73 * Management of resident (logical) pages.
75 * A small structure is kept for each resident
76 * page, indexed by page number. Each structure
77 * is an element of several lists:
79 * A hash table bucket used to quickly
80 * perform object/offset lookups
82 * A list of all pages for a given object,
83 * so they can be quickly deactivated at
84 * time of deallocation.
86 * An ordered list of pages due for pageout.
88 * In addition, the structure contains the object
89 * and offset to which this page belongs (for pageout),
90 * and sundry status bits.
92 * Fields in this structure are locked either by the lock on the
93 * object that the page belongs to (O), its corresponding page lock (P),
94 * or by the lock on the page queues (Q).
98 TAILQ_HEAD(pglist, vm_page);
101 TAILQ_ENTRY(vm_page) pageq; /* queue info for FIFO queue or free list (Q) */
102 TAILQ_ENTRY(vm_page) listq; /* pages in same object (O) */
103 struct vm_page *left; /* splay tree link (O) */
104 struct vm_page *right; /* splay tree link (O) */
106 vm_object_t object; /* which object am I in (O,P)*/
107 vm_pindex_t pindex; /* offset into object (O,Q) */
108 vm_paddr_t phys_addr; /* physical address of page */
109 struct md_page md; /* machine dependant stuff */
110 uint8_t queue; /* page queue index (P,Q) */
112 u_short flags; /* see below */
113 uint8_t order; /* index of the buddy queue */
115 u_short cow; /* page cow mapping count (P) */
116 u_int wire_count; /* wired down maps refs (P) */
117 short hold_count; /* page hold count (P) */
118 u_short oflags; /* page flags (O) */
119 u_char act_count; /* page usage count (P) */
120 u_char busy; /* page busy count (O) */
121 /* NOTE that these must support one bit per DEV_BSIZE in a page!!! */
122 /* so, on normal X86 kernels, they must be at least 8 bits wide */
123 #if PAGE_SIZE == 4096
124 u_char valid; /* map of valid DEV_BSIZE chunks (O) */
125 u_char dirty; /* map of dirty DEV_BSIZE chunks (O) */
126 #elif PAGE_SIZE == 8192
127 u_short valid; /* map of valid DEV_BSIZE chunks (O) */
128 u_short dirty; /* map of dirty DEV_BSIZE chunks (O) */
129 #elif PAGE_SIZE == 16384
130 u_int valid; /* map of valid DEV_BSIZE chunks (O) */
131 u_int dirty; /* map of dirty DEV_BSIZE chunks (O) */
132 #elif PAGE_SIZE == 32768
133 u_long valid; /* map of valid DEV_BSIZE chunks (O) */
134 u_long dirty; /* map of dirty DEV_BSIZE chunks (O) */
139 * Page flags stored in oflags:
141 * Access to these page flags is synchronized by the lock on the object
142 * containing the page (O).
144 #define VPO_BUSY 0x0001 /* page is in transit */
145 #define VPO_WANTED 0x0002 /* someone is waiting for page */
146 #define VPO_SWAPINPROG 0x0200 /* swap I/O in progress on page */
147 #define VPO_NOSYNC 0x0400 /* do not collect for syncer */
150 #define PQ_INACTIVE 1
160 extern struct vpgqueues vm_page_queues[PQ_COUNT];
164 char pad[CACHE_LINE_SIZE - sizeof(struct mtx)];
165 } __aligned(CACHE_LINE_SIZE);
167 extern struct vpglocks vm_page_queue_free_lock;
168 extern struct vpglocks pa_lock[];
171 #define PDRSHIFT PDR_SHIFT
172 #elif !defined(PDRSHIFT)
176 #define pa_index(pa) ((pa) >> PDRSHIFT)
177 #define PA_LOCKPTR(pa) &pa_lock[pa_index((pa)) % PA_LOCK_COUNT].data
178 #define PA_LOCKOBJPTR(pa) ((struct lock_object *)PA_LOCKPTR((pa)))
179 #define PA_LOCK(pa) mtx_lock(PA_LOCKPTR(pa))
180 #define PA_TRYLOCK(pa) mtx_trylock(PA_LOCKPTR(pa))
181 #define PA_UNLOCK(pa) mtx_unlock(PA_LOCKPTR(pa))
182 #define PA_UNLOCK_COND(pa) \
190 #define PA_LOCK_ASSERT(pa, a) mtx_assert(PA_LOCKPTR(pa), (a))
192 #define vm_page_lockptr(m) (PA_LOCKPTR(VM_PAGE_TO_PHYS((m))))
193 #define vm_page_lock(m) mtx_lock(vm_page_lockptr((m)))
194 #define vm_page_unlock(m) mtx_unlock(vm_page_lockptr((m)))
195 #define vm_page_trylock(m) mtx_trylock(vm_page_lockptr((m)))
196 #define vm_page_lock_assert(m, a) mtx_assert(vm_page_lockptr((m)), (a))
198 #define vm_page_queue_free_mtx vm_page_queue_free_lock.data
200 * These are the flags defined for vm_page.
202 * Note: PG_UNMANAGED (used by OBJT_PHYS) indicates that the page is
203 * not under PV management but otherwise should be treated as a
204 * normal page. Pages not under PV management cannot be paged out
205 * via the object/vm_page_t because there is no knowledge of their
206 * pte mappings, nor can they be removed from their objects via
207 * the object, and such pages are also not on any PQ queue.
209 * PG_REFERENCED may be cleared only if the object containing the page is
212 * PG_WRITEABLE is set exclusively on managed pages by pmap_enter(). When it
213 * does so, the page must be VPO_BUSY.
215 #define PG_CACHED 0x0001 /* page is cached */
216 #define PG_FREE 0x0002 /* page is free */
217 #define PG_WINATCFLS 0x0004 /* flush dirty page on inactive q */
218 #define PG_FICTITIOUS 0x0008 /* physical page doesn't exist (O) */
219 #define PG_WRITEABLE 0x0010 /* page is mapped writeable */
220 #define PG_ZERO 0x0040 /* page is zeroed */
221 #define PG_REFERENCED 0x0080 /* page has been referenced */
222 #define PG_UNMANAGED 0x0800 /* No PV management for page */
223 #define PG_MARKER 0x1000 /* special queue marker page */
224 #define PG_SLAB 0x2000 /* object pointer is actually a slab */
229 #define ACT_DECLINE 1
230 #define ACT_ADVANCE 3
236 #include <vm/vm_param.h>
239 * Each pageable resident page falls into one of five lists:
242 * Available for allocation now.
245 * Almost available for allocation. Still associated with
246 * an object, but clean and immediately freeable.
249 * Will become free after a pending I/O operation
252 * The following lists are LRU sorted:
255 * Low activity, candidates for reclamation.
256 * This is the list of pages that should be
260 * Pages that are "active" i.e. they have been
261 * recently referenced.
266 extern int vm_page_zero_count;
268 extern vm_page_t vm_page_array; /* First resident page in table */
269 extern int vm_page_array_size; /* number of vm_page_t's */
270 extern long first_page; /* first physical page number */
272 #define VM_PAGE_IS_FREE(m) (((m)->flags & PG_FREE) != 0)
274 #define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr)
276 vm_page_t vm_phys_paddr_to_vm_page(vm_paddr_t pa);
278 static __inline vm_page_t PHYS_TO_VM_PAGE(vm_paddr_t pa);
280 static __inline vm_page_t
281 PHYS_TO_VM_PAGE(vm_paddr_t pa)
283 #ifdef VM_PHYSSEG_SPARSE
284 return (vm_phys_paddr_to_vm_page(pa));
285 #elif defined(VM_PHYSSEG_DENSE)
286 return (&vm_page_array[atop(pa) - first_page]);
288 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined."
292 extern struct vpglocks vm_page_queue_lock;
294 #define vm_page_queue_mtx vm_page_queue_lock.data
295 #define vm_page_lock_queues() mtx_lock(&vm_page_queue_mtx)
296 #define vm_page_unlock_queues() mtx_unlock(&vm_page_queue_mtx)
298 #if PAGE_SIZE == 4096
299 #define VM_PAGE_BITS_ALL 0xffu
300 #elif PAGE_SIZE == 8192
301 #define VM_PAGE_BITS_ALL 0xffffu
302 #elif PAGE_SIZE == 16384
303 #define VM_PAGE_BITS_ALL 0xffffffffu
304 #elif PAGE_SIZE == 32768
305 #define VM_PAGE_BITS_ALL 0xfffffffffffffffflu
308 /* page allocation classes: */
309 #define VM_ALLOC_NORMAL 0
310 #define VM_ALLOC_INTERRUPT 1
311 #define VM_ALLOC_SYSTEM 2
312 #define VM_ALLOC_CLASS_MASK 3
313 /* page allocation flags: */
314 #define VM_ALLOC_WIRED 0x0020 /* non pageable */
315 #define VM_ALLOC_ZERO 0x0040 /* Try to obtain a zeroed page */
316 #define VM_ALLOC_RETRY 0x0080 /* Mandatory with vm_page_grab() */
317 #define VM_ALLOC_NOOBJ 0x0100 /* No associated object */
318 #define VM_ALLOC_NOBUSY 0x0200 /* Do not busy the page */
319 #define VM_ALLOC_IFCACHED 0x0400 /* Fail if the page is not cached */
320 #define VM_ALLOC_IFNOTCACHED 0x0800 /* Fail if the page is cached */
321 #define VM_ALLOC_IGN_SBUSY 0x1000 /* vm_page_grab() only */
323 #define VM_ALLOC_COUNT_SHIFT 16
324 #define VM_ALLOC_COUNT(count) ((count) << VM_ALLOC_COUNT_SHIFT)
326 void vm_page_flag_set(vm_page_t m, unsigned short bits);
327 void vm_page_flag_clear(vm_page_t m, unsigned short bits);
328 void vm_page_busy(vm_page_t m);
329 void vm_page_flash(vm_page_t m);
330 void vm_page_io_start(vm_page_t m);
331 void vm_page_io_finish(vm_page_t m);
332 void vm_page_hold(vm_page_t mem);
333 void vm_page_unhold(vm_page_t mem);
334 void vm_page_free(vm_page_t m);
335 void vm_page_free_zero(vm_page_t m);
336 void vm_page_dirty(vm_page_t m);
337 void vm_page_wakeup(vm_page_t m);
339 void vm_pageq_remove(vm_page_t m);
341 void vm_page_activate (vm_page_t);
342 vm_page_t vm_page_alloc (vm_object_t, vm_pindex_t, int);
343 vm_page_t vm_page_alloc_freelist(int, int, int);
344 struct vnode *vm_page_alloc_init(vm_page_t);
345 vm_page_t vm_page_grab (vm_object_t, vm_pindex_t, int);
346 void vm_page_cache(vm_page_t);
347 void vm_page_cache_free(vm_object_t, vm_pindex_t, vm_pindex_t);
348 void vm_page_cache_remove(vm_page_t);
349 void vm_page_cache_transfer(vm_object_t, vm_pindex_t, vm_object_t);
350 int vm_page_try_to_cache (vm_page_t);
351 int vm_page_try_to_free (vm_page_t);
352 void vm_page_dontneed(vm_page_t);
353 void vm_page_deactivate (vm_page_t);
354 vm_page_t vm_page_find_least(vm_object_t, vm_pindex_t);
355 void vm_page_insert (vm_page_t, vm_object_t, vm_pindex_t);
356 vm_page_t vm_page_lookup (vm_object_t, vm_pindex_t);
357 vm_page_t vm_page_next(vm_page_t m);
358 int vm_page_pa_tryrelock(pmap_t, vm_paddr_t, vm_paddr_t *);
359 vm_page_t vm_page_prev(vm_page_t m);
360 void vm_page_remove (vm_page_t);
361 void vm_page_rename (vm_page_t, vm_object_t, vm_pindex_t);
362 void vm_page_requeue(vm_page_t m);
363 void vm_page_set_valid(vm_page_t m, int base, int size);
364 void vm_page_sleep(vm_page_t m, const char *msg);
365 vm_page_t vm_page_splay(vm_pindex_t, vm_page_t);
366 vm_offset_t vm_page_startup(vm_offset_t vaddr);
367 void vm_page_unwire (vm_page_t, int);
368 void vm_page_wire (vm_page_t);
369 void vm_page_set_validclean (vm_page_t, int, int);
370 void vm_page_clear_dirty (vm_page_t, int, int);
371 void vm_page_set_invalid (vm_page_t, int, int);
372 int vm_page_is_valid (vm_page_t, int, int);
373 void vm_page_test_dirty (vm_page_t);
374 int vm_page_bits (int, int);
375 void vm_page_zero_invalid(vm_page_t m, boolean_t setvalid);
376 void vm_page_free_toq(vm_page_t m);
377 void vm_page_zero_idle_wakeup(void);
378 void vm_page_cowfault (vm_page_t);
379 int vm_page_cowsetup(vm_page_t);
380 void vm_page_cowclear (vm_page_t);
383 * vm_page_sleep_if_busy:
385 * Sleep and release the page queues lock if VPO_BUSY is set or,
386 * if also_m_busy is TRUE, busy is non-zero. Returns TRUE if the
387 * thread slept and the page queues lock was released.
388 * Otherwise, retains the page queues lock and returns FALSE.
390 * The object containing the given page must be locked.
393 vm_page_sleep_if_busy(vm_page_t m, int also_m_busy, const char *msg)
396 if ((m->oflags & VPO_BUSY) || (also_m_busy && m->busy)) {
397 vm_page_sleep(m, msg);
406 * Set page to not be dirty. Note: does not clear pmap modify bits
409 vm_page_undirty(vm_page_t m)
415 #endif /* !_VM_PAGE_ */