osfmk/vm/vm_page.h

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
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   6  * This file contains Original Code and/or Modifications of Original Code
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   8  * Version 2.0 (the 'License'). You may not use this file except in
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  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
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  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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  23  * Please see the License for the specific language governing rights and
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  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991,1990,1989,1988 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56 /*
  57  */
  58 /*
  59  *      File:   vm/vm_page.h
  60  *      Author: Avadis Tevanian, Jr., Michael Wayne Young
  61  *      Date:   1985
  62  *
  63  *      Resident memory system definitions.
  64  */
  65
  66 #ifndef _VM_VM_PAGE_H_
  67 #define _VM_VM_PAGE_H_
  68
  69 #include <debug.h>
  70
  71 #include <mach/boolean.h>
  72 #include <mach/vm_prot.h>
  73 #include <mach/vm_param.h>
  74 #include <vm/vm_object.h>
  75 #include <kern/queue.h>
  76 #include <kern/lock.h>
  77
  78 #include <kern/macro_help.h>
  79
  80 /*
  81  * Each page entered on the inactive queue obtains a ticket from a
  82  * particular ticket roll.  Pages granted tickets from a particular
  83  * roll  generally flow through the queue as a group.  In this way when a
  84  * page with a ticket from a particular roll is pulled from the top of the
  85  * queue it is extremely likely that the pages near the top will have tickets
  86  * from the same or adjacent rolls.  In this way the proximity to the top
  87  * of the queue can be loosely ascertained by determining the identity of
  88  * the roll the pages ticket came from.
  89  */
  90
  91
  92 extern unsigned int     vm_page_ticket_roll;
  93 extern unsigned int     vm_page_ticket;
  94
  95
  96 #define VM_PAGE_TICKETS_IN_ROLL  512
  97 #define VM_PAGE_TICKET_ROLL_IDS  16
  98
  99 /*
 100  *      Management of resident (logical) pages.
 101  *
 102  *      A small structure is kept for each resident
 103  *      page, indexed by page number.  Each structure
 104  *      is an element of several lists:
 105  *
 106  *              A hash table bucket used to quickly
 107  *              perform object/offset lookups
 108  *
 109  *              A list of all pages for a given object,
 110  *              so they can be quickly deactivated at
 111  *              time of deallocation.
 112  *
 113  *              An ordered list of pages due for pageout.
 114  *
 115  *      In addition, the structure contains the object
 116  *      and offset to which this page belongs (for pageout),
 117  *      and sundry status bits.
 118  *
 119  *      Fields in this structure are locked either by the lock on the
 120  *      object that the page belongs to (O) or by the lock on the page
 121  *      queues (P).  [Some fields require that both locks be held to
 122  *      change that field; holding either lock is sufficient to read.]
 123  */
 124
 125 struct vm_page {
 126         queue_chain_t   pageq;          /* queue info for FIFO
 127                                          * queue or free list (P) */
 128         queue_chain_t   listq;          /* all pages in same object (O) */
 129         struct vm_page  *next;          /* VP bucket link (O) */
 130
 131         vm_object_t     object;         /* which object am I in (O&P) */
 132         vm_object_offset_t offset;      /* offset into that object (O,P) */
 133
 134         /*
 135          * The following word of flags is protected
 136          * by the "page queues" lock.
 137          */
 138         unsigned int    wire_count:16,  /* how many wired down maps use me? (O&P) */
 139                         page_ticket:4,  /* age of the page on the       */
 140                                         /* inactive queue.                  */
 141         /* boolean_t */ inactive:1,     /* page is in inactive list (P) */
 142                         active:1,       /* page is in active list (P) */
 143                         pageout_queue:1,/* page is on queue for pageout (P) */
 144                         laundry:1,      /* page is being cleaned now (P)*/
 145                         free:1,         /* page is on free list (P) */
 146                         reference:1,    /* page has been used (P) */
 147                         pageout:1,      /* page wired & busy for pageout (P) */
 148                         gobbled:1,      /* page used internally (P) */
 149                         private:1,      /* Page should not be returned to
 150                                          *  the free list (P) */
 151                         zero_fill:1,
 152                         :0;
 153
 154         /*
 155          * The following word of flags is protected
 156          * by the "VM object" lock.
 157          */
 158         unsigned int
 159                         page_error:8,   /* error from I/O operations */
 160         /* boolean_t */ busy:1,         /* page is in transit (O) */
 161                         wanted:1,       /* someone is waiting for page (O) */
 162                         tabled:1,       /* page is in VP table (O) */
 163                         fictitious:1,   /* Physical page doesn't exist (O) */
 164                         no_isync:1,     /* page has not been instruction synced */
 165                         absent:1,       /* Data has been requested, but is
 166                                          *  not yet available (O) */
 167                         error:1,        /* Data manager was unable to provide
 168                                          *  data due to error (O) */
 169                         dirty:1,        /* Page must be cleaned (O) */
 170                         cleaning:1,     /* Page clean has begun (O) */
 171                         precious:1,     /* Page is precious; data must be
 172                                          *  returned even if clean (O) */
 173                         clustered:1,    /* page is not the faulted page (O) */
 174                         overwriting:1,  /* Request to unlock has been made
 175                                          * without having data. (O)
 176                                          * [See vm_fault_page_overwrite] */
 177                         restart:1,      /* Page was pushed higher in shadow
 178                                            chain by copy_call-related pagers;
 179                                            start again at top of chain */
 180                         lock_supplied:1,/* protection supplied by pager (O) */
 181         /* vm_prot_t */ page_lock:3,    /* Uses prohibited by pager (O) */
 182         /* vm_prot_t */ unlock_request:3,/* Outstanding unlock request (O) */
 183                         unusual:1,      /* Page is absent, error, restart or
 184                                            page locked */
 185                         encrypted:1,    /* encrypted for secure swap (O) */
 186                         list_req_pending:1, /* pagein/pageout alt mechanism */
 187                                             /* allows creation of list      */
 188                                             /* requests on pages that are   */
 189                                             /* actively being paged.        */
 190                         dump_cleaning:1;   /* set by the pageout daemon when */
 191                                            /* a page being cleaned is       */
 192                                            /* encountered and targeted as   */
 193                                            /* a pageout candidate           */
 194         /* we've used up all 32 bits */
 195
 196         ppnum_t         phys_page;      /* Physical address of page, passed
 197                                          *  to pmap_enter (read-only) */
 198 };
 199
 200 #define DEBUG_ENCRYPTED_SWAP    1
 201 #if DEBUG_ENCRYPTED_SWAP
 202 #define ASSERT_PAGE_DECRYPTED(page)                                     \
 203         MACRO_BEGIN                                                     \
 204         if ((page)->encrypted) {                                        \
 205                 panic("VM page %p should not be encrypted here\n",      \
 206                       (page));                                          \
 207         }                                                               \
 208         MACRO_END
 209 #else   /* DEBUG_ENCRYPTED_SWAP */
 210 #define ASSERT_PAGE_DECRYPTED(page) assert(!(page)->encrypted)
 211 #endif  /* DEBUG_ENCRYPTED_SWAP */
 212
 213 typedef struct vm_page  *vm_page_t;
 214
 215 #define VM_PAGE_NULL            ((vm_page_t) 0)
 216 #define NEXT_PAGE(m)            ((vm_page_t) (m)->pageq.next)
 217 #define NEXT_PAGE_PTR(m)        ((vm_page_t *) &(m)->pageq.next)
 218
 219 /*
 220  * XXX  The unusual bit should not be necessary.  Most of the bit
 221  * XXX  fields above really want to be masks.
 222  */
 223
 224 /*
 225  *      For debugging, this macro can be defined to perform
 226  *      some useful check on a page structure.
 227  */
 228
 229 #define VM_PAGE_CHECK(mem)
 230
 231 /*
 232  *      Each pageable resident page falls into one of three lists:
 233  *
 234  *      free
 235  *              Available for allocation now.
 236  *      inactive
 237  *              Not referenced in any map, but still has an
 238  *              object/offset-page mapping, and may be dirty.
 239  *              This is the list of pages that should be
 240  *              paged out next.
 241  *      active
 242  *              A list of pages which have been placed in
 243  *              at least one physical map.  This list is
 244  *              ordered, in LRU-like fashion.
 245  */
 246
 247 extern
 248 vm_page_t       vm_page_queue_free;     /* memory free queue */
 249 extern
 250 vm_page_t       vm_page_queue_fictitious;       /* fictitious free queue */
 251 extern
 252 queue_head_t    vm_page_queue_active;   /* active memory queue */
 253 extern
 254 queue_head_t    vm_page_queue_inactive; /* inactive memory queue */
 255 queue_head_t    vm_page_queue_zf;       /* inactive memory queue for zero fill */
 256
 257 extern
 258 vm_offset_t     first_phys_addr;        /* physical address for first_page */
 259 extern
 260 vm_offset_t     last_phys_addr;         /* physical address for last_page */
 261
 262 extern
 263 unsigned int    vm_page_free_count;     /* How many pages are free? */
 264 extern
 265 unsigned int    vm_page_fictitious_count;/* How many fictitious pages are free? */
 266 extern
 267 unsigned int    vm_page_active_count;   /* How many pages are active? */
 268 extern
 269 unsigned int    vm_page_inactive_count; /* How many pages are inactive? */
 270 extern
 271 unsigned int    vm_page_wire_count;     /* How many pages are wired? */
 272 extern
 273 unsigned int    vm_page_free_target;    /* How many do we want free? */
 274 extern
 275 unsigned int    vm_page_free_min;       /* When to wakeup pageout */
 276 extern
 277 unsigned int    vm_page_inactive_target;/* How many do we want inactive? */
 278 extern
 279 unsigned int    vm_page_free_reserved;  /* How many pages reserved to do pageout */
 280 extern
 281 unsigned int    vm_page_throttled_count;/* Count of zero-fill allocations throttled */
 282 extern
 283 unsigned int    vm_page_gobble_count;
 284
 285 extern
 286 unsigned int    vm_page_purgeable_count;/* How many pages are purgeable now ? */
 287 extern
 288 uint64_t        vm_page_purged_count;   /* How many pages got purged so far ? */
 289
 290 decl_mutex_data(,vm_page_queue_lock)
 291                                 /* lock on active and inactive page queues */
 292 decl_mutex_data(,vm_page_queue_free_lock)
 293                                 /* lock on free page queue */
 294
 295 extern unsigned int     vm_page_free_wanted;
 296                                 /* how many threads are waiting for memory */
 297
 298 extern vm_offset_t      vm_page_fictitious_addr;
 299                                 /* (fake) phys_addr of fictitious pages */
 300
 301 extern boolean_t        vm_page_deactivate_hint;
 302
 303 // 0 = all pages avail, 1 = disable high mem, 2 = prefer himem
 304 extern int              vm_himemory_mode;
 305
 306 extern ppnum_t          vm_lopage_poolend;
 307 extern int              vm_lopage_poolsize;
 308 extern uint64_t         max_valid_dma_address;
 309
 310
 311 /*
 312  * Prototypes for functions exported by this module.
 313  */
 314 extern void             vm_page_bootstrap(
 315                                         vm_offset_t     *startp,
 316                                         vm_offset_t     *endp);
 317
 318 extern void             vm_page_module_init(void);
 319
 320 extern void             vm_page_create(
 321                                         ppnum_t         start,
 322                                         ppnum_t         end);
 323
 324 extern vm_page_t        vm_page_lookup(
 325                                         vm_object_t             object,
 326                                         vm_object_offset_t      offset);
 327
 328 extern vm_page_t        vm_page_grab_fictitious(void);
 329
 330 extern void             vm_page_release_fictitious(
 331                                         vm_page_t page);
 332
 333 extern boolean_t        vm_page_convert(
 334                                         vm_page_t       page);
 335
 336 extern void             vm_page_more_fictitious(void);
 337
 338 extern int              vm_pool_low(void);
 339
 340 extern vm_page_t        vm_page_grab(void);
 341
 342 extern vm_page_t        vm_page_grablo(void);
 343
 344 extern void             vm_page_release(
 345                                         vm_page_t       page);
 346
 347 extern boolean_t        vm_page_wait(
 348                                         int             interruptible );
 349
 350 extern vm_page_t        vm_page_alloc(
 351                                         vm_object_t             object,
 352                                         vm_object_offset_t      offset);
 353
 354 extern vm_page_t        vm_page_alloclo(
 355                                         vm_object_t             object,
 356                                         vm_object_offset_t      offset);
 357
 358 extern void             vm_page_init(
 359                                         vm_page_t       page,
 360                                         ppnum_t         phys_page);
 361
 362 extern void             vm_page_free(
 363                                         vm_page_t       page);
 364
 365 extern void             vm_page_activate(
 366                                         vm_page_t       page);
 367
 368 extern void             vm_page_deactivate(
 369                                         vm_page_t       page);
 370
 371 extern void             vm_page_rename(
 372                                         vm_page_t               page,
 373                                         vm_object_t             new_object,
 374                                         vm_object_offset_t      new_offset);
 375
 376 extern void             vm_page_insert(
 377                                         vm_page_t               page,
 378                                         vm_object_t             object,
 379                                         vm_object_offset_t      offset);
 380
 381 extern void             vm_page_replace(
 382                                         vm_page_t               mem,
 383                                         vm_object_t             object,
 384                                         vm_object_offset_t      offset);
 385
 386 extern void             vm_page_remove(
 387                                         vm_page_t       page);
 388
 389 extern void             vm_page_zero_fill(
 390                                         vm_page_t       page);
 391
 392 extern void             vm_page_part_zero_fill(
 393                                         vm_page_t       m,
 394                                         vm_offset_t     m_pa,
 395                                         vm_size_t       len);
 396
 397 extern void             vm_page_copy(
 398                                         vm_page_t       src_page,
 399                                         vm_page_t       dest_page);
 400
 401 extern void             vm_page_part_copy(
 402                                         vm_page_t       src_m,
 403                                         vm_offset_t     src_pa,
 404                                         vm_page_t       dst_m,
 405                                         vm_offset_t     dst_pa,
 406                                         vm_size_t       len);
 407
 408 extern void             vm_page_wire(
 409                                         vm_page_t       page);
 410
 411 extern void             vm_page_unwire(
 412                                         vm_page_t       page);
 413
 414 extern void             vm_set_page_size(void);
 415
 416 extern void             vm_page_gobble(
 417                                         vm_page_t      page);
 418
 419 /*
 420  *      Functions implemented as macros. m->wanted and m->busy are
 421  *      protected by the object lock.
 422  */
 423
 424 #define PAGE_ASSERT_WAIT(m, interruptible)                      \
 425                 (((m)->wanted = TRUE),                          \
 426                  assert_wait((event_t) (m), (interruptible)))
 427
 428 #define PAGE_SLEEP(o, m, interruptible)                         \
 429                 (((m)->wanted = TRUE),                          \
 430                  thread_sleep_vm_object((o), (m), (interruptible)))
 431
 432 #define PAGE_WAKEUP_DONE(m)                                     \
 433                 MACRO_BEGIN                                     \
 434                 (m)->busy = FALSE;                              \
 435                 if ((m)->wanted) {                              \
 436                         (m)->wanted = FALSE;                    \
 437                         thread_wakeup((event_t) (m));           \
 438                 }                                               \
 439                 MACRO_END
 440
 441 #define PAGE_WAKEUP(m)                                          \
 442                 MACRO_BEGIN                                     \
 443                 if ((m)->wanted) {                              \
 444                         (m)->wanted = FALSE;                    \
 445                         thread_wakeup((event_t) (m));           \
 446                 }                                               \
 447                 MACRO_END
 448
 449 #define VM_PAGE_FREE(p)                         \
 450                 MACRO_BEGIN                     \
 451                 vm_page_lock_queues();          \
 452                 vm_page_free(p);                \
 453                 vm_page_unlock_queues();        \
 454                 MACRO_END
 455
 456 #define VM_PAGE_GRAB_FICTITIOUS(M)                                      \
 457                 MACRO_BEGIN                                             \
 458                 while ((M = vm_page_grab_fictitious()) == VM_PAGE_NULL) \
 459                         vm_page_more_fictitious();                      \
 460                 MACRO_END
 461
 462 #define VM_PAGE_THROTTLED()                                             \
 463                 (vm_page_free_count < vm_page_free_min &&               \
 464                  !(current_thread()->options & TH_OPT_VMPRIV) &&                        \
 465                  ++vm_page_throttled_count)
 466
 467 #define VM_PAGE_WAIT()          ((void)vm_page_wait(THREAD_UNINT))
 468
 469 #define vm_page_lock_queues()   mutex_lock(&vm_page_queue_lock)
 470 #define vm_page_unlock_queues() mutex_unlock(&vm_page_queue_lock)
 471
 472 #define VM_PAGE_QUEUES_REMOVE(mem)                              \
 473         MACRO_BEGIN                                             \
 474         assert(!mem->laundry);                                  \
 475         if (mem->active) {                                      \
 476                 assert(mem->object != kernel_object);           \
 477                 assert(!mem->inactive);                         \
 478                 queue_remove(&vm_page_queue_active,             \
 479                         mem, vm_page_t, pageq);                 \
 480                 mem->pageq.next = NULL;                         \
 481                 mem->pageq.prev = NULL;                         \
 482                 mem->active = FALSE;                            \
 483                 if (!mem->fictitious)                           \
 484                         vm_page_active_count--;                 \
 485         }                                                       \
 486                                                                 \
 487         if (mem->inactive) {                                    \
 488                 assert(mem->object != kernel_object);           \
 489                 assert(!mem->active);                           \
 490                 if (mem->zero_fill) {                           \
 491                         queue_remove(&vm_page_queue_zf,         \
 492                         mem, vm_page_t, pageq);                 \
 493                 } else {                                        \
 494                         queue_remove(&vm_page_queue_inactive,   \
 495                         mem, vm_page_t, pageq);                 \
 496                 }                                               \
 497                 mem->pageq.next = NULL;                         \
 498                 mem->pageq.prev = NULL;                         \
 499                 mem->inactive = FALSE;                          \
 500                 if (!mem->fictitious)                           \
 501                         vm_page_inactive_count--;               \
 502         }                                                       \
 503         MACRO_END
 504
 505 #endif  /* _VM_VM_PAGE_H_ */