1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 27 /* All Rights Reserved */ 28 29 /* 30 * University Copyright- Copyright (c) 1982, 1986, 1988 31 * The Regents of the University of California 32 * All Rights Reserved 33 * 34 * University Acknowledgment- Portions of this document are derived from 35 * software developed by the University of California, Berkeley, and its 36 * contributors. 37 */ 38 39 #ifndef _VM_PAGE_H 40 #define _VM_PAGE_H 41 42 #include <vm/seg.h> 43 44 #ifdef __cplusplus 45 extern "C" { 46 #endif 47 48 #if defined(_KERNEL) || defined(_KMEMUSER) 49 50 /* 51 * Shared/Exclusive lock. 52 */ 53 54 /* 55 * Types of page locking supported by page_lock & friends. 56 */ 57 typedef enum { 58 SE_SHARED, 59 SE_EXCL /* exclusive lock (value == -1) */ 60 } se_t; 61 62 /* 63 * For requesting that page_lock reclaim the page from the free list. 64 */ 65 typedef enum { 66 P_RECLAIM, /* reclaim page from free list */ 67 P_NO_RECLAIM /* DON`T reclaim the page */ 68 } reclaim_t; 69 70 /* 71 * Callers of page_try_reclaim_lock and page_lock_es can use this flag 72 * to get SE_EXCL access before reader/writers are given access. 73 */ 74 #define SE_EXCL_WANTED 0x02 75 76 /* 77 * All page_*lock() requests will be denied unless this flag is set in 78 * the 'es' parameter. 79 */ 80 #define SE_RETIRED 0x04 81 82 #endif /* _KERNEL | _KMEMUSER */ 83 84 typedef int selock_t; 85 86 /* 87 * Define VM_STATS to turn on all sorts of statistic gathering about 88 * the VM layer. By default, it is only turned on when DEBUG is 89 * also defined. 90 */ 91 #ifdef DEBUG 92 #define VM_STATS 93 #endif /* DEBUG */ 94 95 #ifdef VM_STATS 96 #define VM_STAT_ADD(stat) (stat)++ 97 #define VM_STAT_COND_ADD(cond, stat) ((void) (!(cond) || (stat)++)) 98 #else 99 #define VM_STAT_ADD(stat) 100 #define VM_STAT_COND_ADD(cond, stat) 101 #endif /* VM_STATS */ 102 103 #ifdef _KERNEL 104 105 /* 106 * Macros to acquire and release the page logical lock. 107 */ 108 #define page_struct_lock(pp) mutex_enter(&page_llock) 109 #define page_struct_unlock(pp) mutex_exit(&page_llock) 110 111 #endif /* _KERNEL */ 112 113 #include <sys/t_lock.h> 114 115 struct as; 116 117 /* 118 * Each physical page has a page structure, which is used to maintain 119 * these pages as a cache. A page can be found via a hashed lookup 120 * based on the [vp, offset]. If a page has an [vp, offset] identity, 121 * then it is entered on a doubly linked circular list off the 122 * vnode using the vpnext/vpprev pointers. If the p_free bit 123 * is on, then the page is also on a doubly linked circular free 124 * list using next/prev pointers. If the "p_selock" and "p_iolock" 125 * are held, then the page is currently being read in (exclusive p_selock) 126 * or written back (shared p_selock). In this case, the next/prev pointers 127 * are used to link the pages together for a consecutive i/o request. If 128 * the page is being brought in from its backing store, then other processes 129 * will wait for the i/o to complete before attaching to the page since it 130 * will have an "exclusive" lock. 131 * 132 * Each page structure has the locks described below along with 133 * the fields they protect: 134 * 135 * p_selock This is a per-page shared/exclusive lock that is 136 * used to implement the logical shared/exclusive 137 * lock for each page. The "shared" lock is normally 138 * used in most cases while the "exclusive" lock is 139 * required to destroy or retain exclusive access to 140 * a page (e.g., while reading in pages). The appropriate 141 * lock is always held whenever there is any reference 142 * to a page structure (e.g., during i/o). 143 * (Note that with the addition of the "writer-lock-wanted" 144 * semantics (via SE_EWANTED), threads must not acquire 145 * multiple reader locks or else a deadly embrace will 146 * occur in the following situation: thread 1 obtains a 147 * reader lock; next thread 2 fails to get a writer lock 148 * but specified SE_EWANTED so it will wait by either 149 * blocking (when using page_lock_es) or spinning while 150 * retrying (when using page_try_reclaim_lock) until the 151 * reader lock is released; then thread 1 attempts to 152 * get another reader lock but is denied due to 153 * SE_EWANTED being set, and now both threads are in a 154 * deadly embrace.) 155 * 156 * p_hash 157 * p_vnode 158 * p_offset 159 * 160 * p_free 161 * p_age 162 * 163 * p_iolock This is a binary semaphore lock that provides 164 * exclusive access to the i/o list links in each 165 * page structure. It is always held while the page 166 * is on an i/o list (i.e., involved in i/o). That is, 167 * even though a page may be only `shared' locked 168 * while it is doing a write, the following fields may 169 * change anyway. Normally, the page must be 170 * `exclusively' locked to change anything in it. 171 * 172 * p_next 173 * p_prev 174 * 175 * The following fields are protected by the global page_llock: 176 * 177 * p_lckcnt 178 * p_cowcnt 179 * 180 * The following lists are protected by the global page_freelock: 181 * 182 * page_cachelist 183 * page_freelist 184 * 185 * The following, for our purposes, are protected by 186 * the global freemem_lock: 187 * 188 * freemem 189 * freemem_wait 190 * freemem_cv 191 * 192 * The following fields are protected by hat layer lock(s). When a page 193 * structure is not mapped and is not associated with a vnode (after a call 194 * to page_hashout() for example) the p_nrm field may be modified with out 195 * holding the hat layer lock: 196 * 197 * p_nrm 198 * p_mapping 199 * p_share 200 * 201 * The following field is file system dependent. How it is used and 202 * the locking strategies applied are up to the individual file system 203 * implementation. 204 * 205 * p_fsdata 206 * 207 * The page structure is used to represent and control the system's 208 * physical pages. There is one instance of the structure for each 209 * page that is not permenately allocated. For example, the pages that 210 * hold the page structures are permanently held by the kernel 211 * and hence do not need page structures to track them. The array 212 * of page structures is allocated early on in the kernel's life and 213 * is based on the amount of available physical memory. 214 * 215 * Each page structure may simultaneously appear on several linked lists. 216 * The lists are: hash list, free or in i/o list, and a vnode's page list. 217 * Each type of list is protected by a different group of mutexes as described 218 * below: 219 * 220 * The hash list is used to quickly find a page when the page's vnode and 221 * offset within the vnode are known. Each page that is hashed is 222 * connected via the `p_hash' field. The anchor for each hash is in the 223 * array `page_hash'. An array of mutexes, `ph_mutex', protects the 224 * lists anchored by page_hash[]. To either search or modify a given hash 225 * list, the appropriate mutex in the ph_mutex array must be held. 226 * 227 * The free list contains pages that are `free to be given away'. For 228 * efficiency reasons, pages on this list are placed in two catagories: 229 * pages that are still associated with a vnode, and pages that are not 230 * associated with a vnode. Free pages always have their `p_free' bit set, 231 * free pages that are still associated with a vnode also have their 232 * `p_age' bit set. Pages on the free list are connected via their 233 * `p_next' and `p_prev' fields. When a page is involved in some sort 234 * of i/o, it is not free and these fields may be used to link associated 235 * pages together. At the moment, the free list is protected by a 236 * single mutex `page_freelock'. The list of free pages still associated 237 * with a vnode is anchored by `page_cachelist' while other free pages 238 * are anchored in architecture dependent ways (to handle page coloring etc.). 239 * 240 * Pages associated with a given vnode appear on a list anchored in the 241 * vnode by the `v_pages' field. They are linked together with 242 * `p_vpnext' and `p_vpprev'. The field `p_offset' contains a page's 243 * offset within the vnode. The pages on this list are not kept in 244 * offset order. These lists, in a manner similar to the hash lists, 245 * are protected by an array of mutexes called `vph_hash'. Before 246 * searching or modifying this chain the appropriate mutex in the 247 * vph_hash[] array must be held. 248 * 249 * Again, each of the lists that a page can appear on is protected by a 250 * mutex. Before reading or writing any of the fields comprising the 251 * list, the appropriate lock must be held. These list locks should only 252 * be held for very short intervals. 253 * 254 * In addition to the list locks, each page structure contains a 255 * shared/exclusive lock that protects various fields within it. 256 * To modify one of these fields, the `p_selock' must be exclusively held. 257 * To read a field with a degree of certainty, the lock must be at least 258 * held shared. 259 * 260 * Removing a page structure from one of the lists requires holding 261 * the appropriate list lock and the page's p_selock. A page may be 262 * prevented from changing identity, being freed, or otherwise modified 263 * by acquiring p_selock shared. 264 * 265 * To avoid deadlocks, a strict locking protocol must be followed. Basically 266 * there are two cases: In the first case, the page structure in question 267 * is known ahead of time (e.g., when the page is to be added or removed 268 * from a list). In the second case, the page structure is not known and 269 * must be found by searching one of the lists. 270 * 271 * When adding or removing a known page to one of the lists, first the 272 * page must be exclusively locked (since at least one of its fields 273 * will be modified), second the lock protecting the list must be acquired, 274 * third the page inserted or deleted, and finally the list lock dropped. 275 * 276 * The more interesting case occures when the particular page structure 277 * is not known ahead of time. For example, when a call is made to 278 * page_lookup(), it is not known if a page with the desired (vnode and 279 * offset pair) identity exists. So the appropriate mutex in ph_mutex is 280 * acquired, the hash list searched, and if the desired page is found 281 * an attempt is made to lock it. The attempt to acquire p_selock must 282 * not block while the hash list lock is held. A deadlock could occure 283 * if some other process was trying to remove the page from the list. 284 * The removing process (following the above protocol) would have exclusively 285 * locked the page, and be spinning waiting to acquire the lock protecting 286 * the hash list. Since the searching process holds the hash list lock 287 * and is waiting to acquire the page lock, a deadlock occurs. 288 * 289 * The proper scheme to follow is: first, lock the appropriate list, 290 * search the list, and if the desired page is found either use 291 * page_trylock() (which will not block) or pass the address of the 292 * list lock to page_lock(). If page_lock() can not acquire the page's 293 * lock, it will drop the list lock before going to sleep. page_lock() 294 * returns a value to indicate if the list lock was dropped allowing the 295 * calling program to react appropriately (i.e., retry the operation). 296 * 297 * If the list lock was dropped before the attempt at locking the page 298 * was made, checks would have to be made to ensure that the page had 299 * not changed identity before its lock was obtained. This is because 300 * the interval between dropping the list lock and acquiring the page 301 * lock is indeterminate. 302 * 303 * In addition, when both a hash list lock (ph_mutex[]) and a vnode list 304 * lock (vph_mutex[]) are needed, the hash list lock must be acquired first. 305 * The routine page_hashin() is a good example of this sequence. 306 * This sequence is ASSERTed by checking that the vph_mutex[] is not held 307 * just before each acquisition of one of the mutexs in ph_mutex[]. 308 * 309 * So, as a quick summary: 310 * 311 * pse_mutex[]'s protect the p_selock and p_cv fields. 312 * 313 * p_selock protects the p_free, p_age, p_vnode, p_offset and p_hash, 314 * 315 * ph_mutex[]'s protect the page_hash[] array and its chains. 316 * 317 * vph_mutex[]'s protect the v_pages field and the vp page chains. 318 * 319 * First lock the page, then the hash chain, then the vnode chain. When 320 * this is not possible `trylocks' must be used. Sleeping while holding 321 * any of these mutexes (p_selock is not a mutex) is not allowed. 322 * 323 * 324 * field reading writing ordering 325 * ====================================================================== 326 * p_vnode p_selock(E,S) p_selock(E) 327 * p_offset 328 * p_free 329 * p_age 330 * ===================================================================== 331 * p_hash p_selock(E,S) p_selock(E) && p_selock, ph_mutex 332 * ph_mutex[] 333 * ===================================================================== 334 * p_vpnext p_selock(E,S) p_selock(E) && p_selock, vph_mutex 335 * p_vpprev vph_mutex[] 336 * ===================================================================== 337 * When the p_free bit is set: 338 * 339 * p_next p_selock(E,S) p_selock(E) && p_selock, 340 * p_prev page_freelock page_freelock 341 * 342 * When the p_free bit is not set: 343 * 344 * p_next p_selock(E,S) p_selock(E) && p_selock, p_iolock 345 * p_prev p_iolock 346 * ===================================================================== 347 * p_selock pse_mutex[] pse_mutex[] can`t acquire any 348 * p_cv other mutexes or 349 * sleep while holding 350 * this lock. 351 * ===================================================================== 352 * p_lckcnt p_selock(E,S) p_selock(E) && 353 * p_cowcnt page_llock 354 * ===================================================================== 355 * p_nrm hat layer lock hat layer lock 356 * p_mapping 357 * p_pagenum 358 * ===================================================================== 359 * 360 * where: 361 * E----> exclusive version of p_selock. 362 * S----> shared version of p_selock. 363 * 364 * 365 * Global data structures and variable: 366 * 367 * field reading writing ordering 368 * ===================================================================== 369 * page_hash[] ph_mutex[] ph_mutex[] can hold this lock 370 * before acquiring 371 * a vph_mutex or 372 * pse_mutex. 373 * ===================================================================== 374 * vp->v_pages vph_mutex[] vph_mutex[] can only acquire 375 * a pse_mutex while 376 * holding this lock. 377 * ===================================================================== 378 * page_cachelist page_freelock page_freelock can't acquire any 379 * page_freelist page_freelock page_freelock 380 * ===================================================================== 381 * freemem freemem_lock freemem_lock can't acquire any 382 * freemem_wait other mutexes while 383 * freemem_cv holding this mutex. 384 * ===================================================================== 385 * 386 * Page relocation, PG_NORELOC and P_NORELOC. 387 * 388 * Pages may be relocated using the page_relocate() interface. Relocation 389 * involves moving the contents and identity of a page to another, free page. 390 * To relocate a page, the SE_EXCL lock must be obtained. The way to prevent 391 * a page from being relocated is to hold the SE_SHARED lock (the SE_EXCL 392 * lock must not be held indefinitely). If the page is going to be held 393 * SE_SHARED indefinitely, then the PG_NORELOC hint should be passed 394 * to page_create_va so that pages that are prevented from being relocated 395 * can be managed differently by the platform specific layer. 396 * 397 * Pages locked in memory using page_pp_lock (p_lckcnt/p_cowcnt != 0) 398 * are guaranteed to be held in memory, but can still be relocated 399 * providing the SE_EXCL lock can be obtained. 400 * 401 * The P_NORELOC bit in the page_t.p_state field is provided for use by 402 * the platform specific code in managing pages when the PG_NORELOC 403 * hint is used. 404 * 405 * Memory delete and page locking. 406 * 407 * The set of all usable pages is managed using the global page list as 408 * implemented by the memseg structure defined below. When memory is added 409 * or deleted this list changes. Additions to this list guarantee that the 410 * list is never corrupt. In order to avoid the necessity of an additional 411 * lock to protect against failed accesses to the memseg being deleted and, 412 * more importantly, the page_ts, the memseg structure is never freed and the 413 * page_t virtual address space is remapped to a page (or pages) of 414 * zeros. If a page_t is manipulated while it is p_selock'd, or if it is 415 * locked indirectly via a hash or freelist lock, it is not possible for 416 * memory delete to collect the page and so that part of the page list is 417 * prevented from being deleted. If the page is referenced outside of one 418 * of these locks, it is possible for the page_t being referenced to be 419 * deleted. Examples of this are page_t pointers returned by 420 * page_numtopp_nolock, page_first and page_next. Providing the page_t 421 * is re-checked after taking the p_selock (for p_vnode != NULL), the 422 * remapping to the zero pages will be detected. 423 * 424 * 425 * Page size (p_szc field) and page locking. 426 * 427 * p_szc field of free pages is changed by free list manager under freelist 428 * locks and is of no concern to the rest of VM subsystem. 429 * 430 * p_szc changes of allocated anonymous (swapfs) can only be done only after 431 * exclusively locking all constituent pages and calling hat_pageunload() on 432 * each of them. To prevent p_szc changes of non free anonymous (swapfs) large 433 * pages it's enough to either lock SHARED any of constituent pages or prevent 434 * hat_pageunload() by holding hat level lock that protects mapping lists (this 435 * method is for hat code only) 436 * 437 * To increase (promote) p_szc of allocated non anonymous file system pages 438 * one has to first lock exclusively all involved constituent pages and call 439 * hat_pageunload() on each of them. To prevent p_szc promote it's enough to 440 * either lock SHARED any of constituent pages that will be needed to make a 441 * large page or prevent hat_pageunload() by holding hat level lock that 442 * protects mapping lists (this method is for hat code only). 443 * 444 * To decrease (demote) p_szc of an allocated non anonymous file system large 445 * page one can either use the same method as used for changeing p_szc of 446 * anonymous large pages or if it's not possible to lock all constituent pages 447 * exclusively a different method can be used. In the second method one only 448 * has to exclusively lock one of constituent pages but then one has to 449 * acquire further locks by calling page_szc_lock() and 450 * hat_page_demote(). hat_page_demote() acquires hat level locks and then 451 * demotes the page. This mechanism relies on the fact that any code that 452 * needs to prevent p_szc of a file system large page from changeing either 453 * locks all constituent large pages at least SHARED or locks some pages at 454 * least SHARED and calls page_szc_lock() or uses hat level page locks. 455 * Demotion using this method is implemented by page_demote_vp_pages(). 456 * Please see comments in front of page_demote_vp_pages(), hat_page_demote() 457 * and page_szc_lock() for more details. 458 * 459 * Lock order: p_selock, page_szc_lock, ph_mutex/vph_mutex/freelist, 460 * hat level locks. 461 */ 462 463 typedef struct page { 464 u_offset_t p_offset; /* offset into vnode for this page */ 465 struct vnode *p_vnode; /* vnode that this page is named by */ 466 selock_t p_selock; /* shared/exclusive lock on the page */ 467 #if defined(_LP64) 468 uint_t p_vpmref; /* vpm ref - index of the vpmap_t */ 469 #endif 470 struct page *p_hash; /* hash by [vnode, offset] */ 471 struct page *p_vpnext; /* next page in vnode list */ 472 struct page *p_vpprev; /* prev page in vnode list */ 473 struct page *p_next; /* next page in free/intrans lists */ 474 struct page *p_prev; /* prev page in free/intrans lists */ 475 ushort_t p_lckcnt; /* number of locks on page data */ 476 ushort_t p_cowcnt; /* number of copy on write lock */ 477 kcondvar_t p_cv; /* page struct's condition var */ 478 kcondvar_t p_io_cv; /* for iolock */ 479 uchar_t p_iolock_state; /* replaces p_iolock */ 480 volatile uchar_t p_szc; /* page size code */ 481 uchar_t p_fsdata; /* file system dependent byte */ 482 uchar_t p_state; /* p_free, p_noreloc */ 483 uchar_t p_nrm; /* non-cache, ref, mod readonly bits */ 484 #if defined(__sparc) 485 uchar_t p_vcolor; /* virtual color */ 486 #else 487 uchar_t p_embed; /* x86 - changes p_mapping & p_index */ 488 #endif 489 uchar_t p_index; /* MPSS mapping info. Not used on x86 */ 490 uchar_t p_toxic; /* page has an unrecoverable error */ 491 void *p_mapping; /* hat specific translation info */ 492 pfn_t p_pagenum; /* physical page number */ 493 494 uint_t p_share; /* number of translations */ 495 #if defined(_LP64) 496 uint_t p_sharepad; /* pad for growing p_share */ 497 #endif 498 uint_t p_slckcnt; /* number of softlocks */ 499 #if defined(__sparc) 500 uint_t p_kpmref; /* number of kpm mapping sharers */ 501 struct kpme *p_kpmelist; /* kpm specific mapping info */ 502 #else 503 /* index of entry in p_map when p_embed is set */ 504 uint_t p_mlentry; 505 #endif 506 #if defined(_LP64) 507 kmutex_t p_ilock; /* protects p_vpmref */ 508 #else 509 uint64_t p_msresv_2; /* page allocation debugging */ 510 #endif 511 } page_t; 512 513 514 typedef page_t devpage_t; 515 #define devpage page 516 517 #define PAGE_LOCK_MAXIMUM \ 518 ((1 << (sizeof (((page_t *)0)->p_lckcnt) * NBBY)) - 1) 519 520 #define PAGE_SLOCK_MAXIMUM UINT_MAX 521 522 /* 523 * Page hash table is a power-of-two in size, externally chained 524 * through the hash field. PAGE_HASHAVELEN is the average length 525 * desired for this chain, from which the size of the page_hash 526 * table is derived at boot time and stored in the kernel variable 527 * page_hashsz. In the hash function it is given by PAGE_HASHSZ. 528 * 529 * PAGE_HASH_FUNC returns an index into the page_hash[] array. This 530 * index is also used to derive the mutex that protects the chain. 531 * 532 * In constructing the hash function, first we dispose of unimportant bits 533 * (page offset from "off" and the low 3 bits of "vp" which are zero for 534 * struct alignment). Then shift and sum the remaining bits a couple times 535 * in order to get as many source bits from the two source values into the 536 * resulting hashed value. Note that this will perform quickly, since the 537 * shifting/summing are fast register to register operations with no additional 538 * memory references). 539 */ 540 #if defined(_LP64) 541 542 #if NCPU < 4 543 #define PH_TABLE_SIZE 128 544 #define VP_SHIFT 7 545 #else 546 #define PH_TABLE_SIZE 1024 547 #define VP_SHIFT 9 548 #endif 549 550 #else /* 32 bits */ 551 552 #if NCPU < 4 553 #define PH_TABLE_SIZE 16 554 #define VP_SHIFT 7 555 #else 556 #define PH_TABLE_SIZE 128 557 #define VP_SHIFT 9 558 #endif 559 560 #endif /* _LP64 */ 561 562 /* 563 * The amount to use for the successive shifts in the hash function below. 564 * The actual value is LOG2(PH_TABLE_SIZE), so that as many bits as 565 * possible will filter thru PAGE_HASH_FUNC() and PAGE_HASH_MUTEX(). 566 */ 567 #define PH_SHIFT_SIZE (7) 568 569 #define PAGE_HASHSZ page_hashsz 570 #define PAGE_HASHAVELEN 4 571 #define PAGE_HASH_FUNC(vp, off) \ 572 ((((uintptr_t)(off) >> PAGESHIFT) + \ 573 ((uintptr_t)(off) >> (PAGESHIFT + PH_SHIFT_SIZE)) + \ 574 ((uintptr_t)(vp) >> 3) + \ 575 ((uintptr_t)(vp) >> (3 + PH_SHIFT_SIZE)) + \ 576 ((uintptr_t)(vp) >> (3 + 2 * PH_SHIFT_SIZE))) & \ 577 (PAGE_HASHSZ - 1)) 578 #ifdef _KERNEL 579 580 /* 581 * The page hash value is re-hashed to an index for the ph_mutex array. 582 * 583 * For 64 bit kernels, the mutex array is padded out to prevent false 584 * sharing of cache sub-blocks (64 bytes) of adjacent mutexes. 585 * 586 * For 32 bit kernels, we don't want to waste kernel address space with 587 * padding, so instead we rely on the hash function to introduce skew of 588 * adjacent vnode/offset indexes (the left shift part of the hash function). 589 * Since sizeof (kmutex_t) is 8, we shift an additional 3 to skew to a different 590 * 64 byte sub-block. 591 */ 592 typedef struct pad_mutex { 593 kmutex_t pad_mutex; 594 #ifdef _LP64 595 char pad_pad[64 - sizeof (kmutex_t)]; 596 #endif 597 } pad_mutex_t; 598 extern pad_mutex_t ph_mutex[]; 599 600 #define PAGE_HASH_MUTEX(x) \ 601 &(ph_mutex[((x) + ((x) >> VP_SHIFT) + ((x) << 3)) & \ 602 (PH_TABLE_SIZE - 1)].pad_mutex) 603 604 /* 605 * Flags used while creating pages. 606 */ 607 #define PG_EXCL 0x0001 608 #define PG_WAIT 0x0002 609 #define PG_PHYSCONTIG 0x0004 /* NOT SUPPORTED */ 610 #define PG_MATCH_COLOR 0x0008 /* SUPPORTED by free list routines */ 611 #define PG_NORELOC 0x0010 /* Non-relocatable alloc hint. */ 612 /* Page must be PP_ISNORELOC */ 613 #define PG_PANIC 0x0020 /* system will panic if alloc fails */ 614 #define PG_PUSHPAGE 0x0040 /* alloc may use reserve */ 615 #define PG_LOCAL 0x0080 /* alloc from given lgrp only */ 616 617 /* 618 * When p_selock has the SE_EWANTED bit set, threads waiting for SE_EXCL 619 * access are given priority over all other waiting threads. 620 */ 621 #define SE_EWANTED 0x40000000 622 #define PAGE_LOCKED(pp) (((pp)->p_selock & ~SE_EWANTED) != 0) 623 #define PAGE_SHARED(pp) (((pp)->p_selock & ~SE_EWANTED) > 0) 624 #define PAGE_EXCL(pp) ((pp)->p_selock < 0) 625 #define PAGE_LOCKED_SE(pp, se) \ 626 ((se) == SE_EXCL ? PAGE_EXCL(pp) : PAGE_SHARED(pp)) 627 628 extern long page_hashsz; 629 extern page_t **page_hash; 630 631 extern kmutex_t page_llock; /* page logical lock mutex */ 632 extern kmutex_t freemem_lock; /* freemem lock */ 633 634 extern pgcnt_t total_pages; /* total pages in the system */ 635 636 /* 637 * Variables controlling locking of physical memory. 638 */ 639 extern pgcnt_t pages_pp_maximum; /* tuning: lock + claim <= max */ 640 extern void init_pages_pp_maximum(void); 641 642 struct lgrp; 643 644 /* page_list_{add,sub} flags */ 645 646 /* which list */ 647 #define PG_FREE_LIST 0x0001 648 #define PG_CACHE_LIST 0x0002 649 650 /* where on list */ 651 #define PG_LIST_TAIL 0x0010 652 #define PG_LIST_HEAD 0x0020 653 654 /* called from */ 655 #define PG_LIST_ISINIT 0x1000 656 657 /* 658 * Page frame operations. 659 */ 660 page_t *page_lookup(struct vnode *, u_offset_t, se_t); 661 page_t *page_lookup_create(struct vnode *, u_offset_t, se_t, page_t *, 662 spgcnt_t *, int); 663 page_t *page_lookup_nowait(struct vnode *, u_offset_t, se_t); 664 page_t *page_find(struct vnode *, u_offset_t); 665 page_t *page_exists(struct vnode *, u_offset_t); 666 int page_exists_physcontig(vnode_t *, u_offset_t, uint_t, page_t *[]); 667 int page_exists_forreal(struct vnode *, u_offset_t, uint_t *); 668 void page_needfree(spgcnt_t); 669 page_t *page_create(struct vnode *, u_offset_t, size_t, uint_t); 670 int page_alloc_pages(struct vnode *, struct seg *, caddr_t, page_t **, 671 page_t **, uint_t, int, int); 672 page_t *page_create_va_large(vnode_t *vp, u_offset_t off, size_t bytes, 673 uint_t flags, struct seg *seg, caddr_t vaddr, void *arg); 674 page_t *page_create_va(struct vnode *, u_offset_t, size_t, uint_t, 675 struct seg *, caddr_t); 676 int page_create_wait(pgcnt_t npages, uint_t flags); 677 void page_create_putback(spgcnt_t npages); 678 void page_free(page_t *, int); 679 void page_free_at_startup(page_t *); 680 void page_free_pages(page_t *); 681 void free_vp_pages(struct vnode *, u_offset_t, size_t); 682 int page_reclaim(page_t *, kmutex_t *); 683 int page_reclaim_pages(page_t *, kmutex_t *, uint_t); 684 void page_destroy(page_t *, int); 685 void page_destroy_pages(page_t *); 686 void page_destroy_free(page_t *); 687 void page_rename(page_t *, struct vnode *, u_offset_t); 688 int page_hashin(page_t *, struct vnode *, u_offset_t, kmutex_t *); 689 void page_hashout(page_t *, kmutex_t *); 690 int page_num_hashin(pfn_t, struct vnode *, u_offset_t); 691 void page_add(page_t **, page_t *); 692 void page_add_common(page_t **, page_t *); 693 void page_sub(page_t **, page_t *); 694 void page_sub_common(page_t **, page_t *); 695 page_t *page_get_freelist(struct vnode *, u_offset_t, struct seg *, 696 caddr_t, size_t, uint_t, struct lgrp *); 697 698 page_t *page_get_cachelist(struct vnode *, u_offset_t, struct seg *, 699 caddr_t, uint_t, struct lgrp *); 700 #if defined(__i386) || defined(__amd64) 701 int page_chk_freelist(uint_t); 702 #endif 703 void page_list_add(page_t *, int); 704 void page_boot_demote(page_t *); 705 void page_promote_size(page_t *, uint_t); 706 void page_list_add_pages(page_t *, int); 707 void page_list_sub(page_t *, int); 708 void page_list_sub_pages(page_t *, uint_t); 709 void page_list_xfer(page_t *, int, int); 710 void page_list_break(page_t **, page_t **, size_t); 711 void page_list_concat(page_t **, page_t **); 712 void page_vpadd(page_t **, page_t *); 713 void page_vpsub(page_t **, page_t *); 714 int page_lock(page_t *, se_t, kmutex_t *, reclaim_t); 715 int page_lock_es(page_t *, se_t, kmutex_t *, reclaim_t, int); 716 void page_lock_clr_exclwanted(page_t *); 717 int page_trylock(page_t *, se_t); 718 int page_try_reclaim_lock(page_t *, se_t, int); 719 int page_tryupgrade(page_t *); 720 void page_downgrade(page_t *); 721 void page_unlock(page_t *); 722 void page_unlock_nocapture(page_t *); 723 void page_lock_delete(page_t *); 724 int page_deleted(page_t *); 725 int page_pp_lock(page_t *, int, int); 726 void page_pp_unlock(page_t *, int, int); 727 int page_resv(pgcnt_t, uint_t); 728 void page_unresv(pgcnt_t); 729 void page_pp_useclaim(page_t *, page_t *, uint_t); 730 int page_addclaim(page_t *); 731 int page_subclaim(page_t *); 732 int page_addclaim_pages(page_t **); 733 int page_subclaim_pages(page_t **); 734 pfn_t page_pptonum(page_t *); 735 page_t *page_numtopp(pfn_t, se_t); 736 page_t *page_numtopp_noreclaim(pfn_t, se_t); 737 page_t *page_numtopp_nolock(pfn_t); 738 page_t *page_numtopp_nowait(pfn_t, se_t); 739 page_t *page_first(); 740 page_t *page_next(page_t *); 741 page_t *page_list_next(page_t *); 742 page_t *page_nextn(page_t *, ulong_t); 743 page_t *page_next_scan_init(void **); 744 page_t *page_next_scan_large(page_t *, ulong_t *, void **); 745 void prefetch_page_r(void *); 746 int ppcopy(page_t *, page_t *); 747 void page_relocate_hash(page_t *, page_t *); 748 void pagezero(page_t *, uint_t, uint_t); 749 void pagescrub(page_t *, uint_t, uint_t); 750 void page_io_lock(page_t *); 751 void page_io_unlock(page_t *); 752 int page_io_trylock(page_t *); 753 int page_iolock_assert(page_t *); 754 void page_iolock_init(page_t *); 755 void page_io_wait(page_t *); 756 int page_io_locked(page_t *); 757 pgcnt_t page_busy(int); 758 void page_lock_init(void); 759 ulong_t page_share_cnt(page_t *); 760 int page_isshared(page_t *); 761 int page_isfree(page_t *); 762 int page_isref(page_t *); 763 int page_ismod(page_t *); 764 int page_release(page_t *, int); 765 void page_retire_init(void); 766 int page_retire(uint64_t, uchar_t); 767 int page_retire_check(uint64_t, uint64_t *); 768 int page_unretire(uint64_t); 769 int page_unretire_pp(page_t *, int); 770 void page_tryretire(page_t *); 771 void page_retire_mdboot(); 772 uint64_t page_retire_pend_count(void); 773 uint64_t page_retire_pend_kas_count(void); 774 void page_retire_incr_pend_count(void *); 775 void page_retire_decr_pend_count(void *); 776 void page_clrtoxic(page_t *, uchar_t); 777 void page_settoxic(page_t *, uchar_t); 778 779 int page_mem_avail(pgcnt_t); 780 int page_reclaim_mem(pgcnt_t, pgcnt_t, int); 781 782 void page_set_props(page_t *, uint_t); 783 void page_clr_all_props(page_t *, int); 784 int page_clear_lck_cow(page_t *, int); 785 786 kmutex_t *page_vnode_mutex(struct vnode *); 787 kmutex_t *page_se_mutex(struct page *); 788 kmutex_t *page_szc_lock(struct page *); 789 int page_szc_lock_assert(struct page *pp); 790 791 /* 792 * Page relocation interfaces. page_relocate() is generic. 793 * page_get_replacement_page() is provided by the PSM. 794 * page_free_replacement_page() is generic. 795 */ 796 int group_page_trylock(page_t *, se_t); 797 void group_page_unlock(page_t *); 798 int page_relocate(page_t **, page_t **, int, int, spgcnt_t *, struct lgrp *); 799 int do_page_relocate(page_t **, page_t **, int, spgcnt_t *, struct lgrp *); 800 page_t *page_get_replacement_page(page_t *, struct lgrp *, uint_t); 801 void page_free_replacement_page(page_t *); 802 int page_relocate_cage(page_t **, page_t **); 803 804 int page_try_demote_pages(page_t *); 805 int page_try_demote_free_pages(page_t *); 806 void page_demote_free_pages(page_t *); 807 808 struct anon_map; 809 810 void page_mark_migrate(struct seg *, caddr_t, size_t, struct anon_map *, 811 ulong_t, vnode_t *, u_offset_t, int); 812 void page_migrate(struct seg *, caddr_t, page_t **, pgcnt_t); 813 814 /* 815 * Tell the PIM we are adding physical memory 816 */ 817 void add_physmem(page_t *, size_t, pfn_t); 818 void add_physmem_cb(page_t *, pfn_t); /* callback for page_t part */ 819 820 /* 821 * hw_page_array[] is configured with hardware supported page sizes by 822 * platform specific code. 823 */ 824 typedef struct { 825 size_t hp_size; 826 uint_t hp_shift; 827 uint_t hp_colors; 828 pgcnt_t hp_pgcnt; /* base pagesize cnt */ 829 } hw_pagesize_t; 830 831 extern hw_pagesize_t hw_page_array[]; 832 extern uint_t page_coloring_shift; 833 extern uint_t page_colors_mask; 834 extern int cpu_page_colors; 835 extern uint_t colorequiv; 836 extern uchar_t colorequivszc[]; 837 838 uint_t page_num_pagesizes(void); 839 uint_t page_num_user_pagesizes(int); 840 size_t page_get_pagesize(uint_t); 841 size_t page_get_user_pagesize(uint_t n); 842 pgcnt_t page_get_pagecnt(uint_t); 843 uint_t page_get_shift(uint_t); 844 int page_szc(size_t); 845 int page_szc_user_filtered(size_t); 846 847 /* page_get_replacement page flags */ 848 #define PGR_SAMESZC 0x1 /* only look for page size same as orig */ 849 #define PGR_NORELOC 0x2 /* allocate a P_NORELOC page */ 850 851 /* 852 * macros for "masked arithmetic" 853 * The purpose is to step through all combinations of a set of bits while 854 * keeping some other bits fixed. Fixed bits need not be contiguous. The 855 * variable bits need not be contiguous either, or even right aligned. The 856 * trick is to set all fixed bits to 1, then increment, then restore the 857 * fixed bits. If incrementing causes a carry from a low bit position, the 858 * carry propagates thru the fixed bits, because they are temporarily set to 1. 859 * v is the value 860 * i is the increment 861 * eq_mask defines the fixed bits 862 * mask limits the size of the result 863 */ 864 #define ADD_MASKED(v, i, eq_mask, mask) \ 865 (((((v) | (eq_mask)) + (i)) & (mask) & ~(eq_mask)) | ((v) & (eq_mask))) 866 867 /* 868 * convenience macro which increments by 1 869 */ 870 #define INC_MASKED(v, eq_mask, mask) ADD_MASKED(v, 1, eq_mask, mask) 871 872 #endif /* _KERNEL */ 873 874 /* 875 * Constants used for the p_iolock_state 876 */ 877 #define PAGE_IO_INUSE 0x1 878 #define PAGE_IO_WANTED 0x2 879 880 /* 881 * Constants used for page_release status 882 */ 883 #define PGREL_NOTREL 0x1 884 #define PGREL_CLEAN 0x2 885 #define PGREL_MOD 0x3 886 887 /* 888 * The p_state field holds what used to be the p_age and p_free 889 * bits. These fields are protected by p_selock (see above). 890 */ 891 #define P_FREE 0x80 /* Page on free list */ 892 #define P_NORELOC 0x40 /* Page is non-relocatable */ 893 #define P_MIGRATE 0x20 /* Migrate page on next touch */ 894 #define P_SWAP 0x10 /* belongs to vnode that is V_ISSWAP */ 895 #define P_BOOTPAGES 0x08 /* member of bootpages list */ 896 897 #define PP_ISFREE(pp) ((pp)->p_state & P_FREE) 898 #define PP_ISAGED(pp) (((pp)->p_state & P_FREE) && \ 899 ((pp)->p_vnode == NULL)) 900 #define PP_ISNORELOC(pp) ((pp)->p_state & P_NORELOC) 901 #define PP_ISKAS(pp) (((pp)->p_vnode == &kvp) || \ 902 ((pp)->p_vnode == &zvp)) 903 #define PP_ISNORELOCKERNEL(pp) (PP_ISNORELOC(pp) && PP_ISKAS(pp)) 904 #define PP_ISMIGRATE(pp) ((pp)->p_state & P_MIGRATE) 905 #define PP_ISSWAP(pp) ((pp)->p_state & P_SWAP) 906 #define PP_ISBOOTPAGES(pp) ((pp)->p_state & P_BOOTPAGES) 907 908 #define PP_SETFREE(pp) ((pp)->p_state = ((pp)->p_state & ~P_MIGRATE) \ 909 | P_FREE) 910 #define PP_SETAGED(pp) ASSERT(PP_ISAGED(pp)) 911 #define PP_SETNORELOC(pp) ((pp)->p_state |= P_NORELOC) 912 #define PP_SETMIGRATE(pp) ((pp)->p_state |= P_MIGRATE) 913 #define PP_SETSWAP(pp) ((pp)->p_state |= P_SWAP) 914 #define PP_SETBOOTPAGES(pp) ((pp)->p_state |= P_BOOTPAGES) 915 916 #define PP_CLRFREE(pp) ((pp)->p_state &= ~P_FREE) 917 #define PP_CLRAGED(pp) ASSERT(!PP_ISAGED(pp)) 918 #define PP_CLRNORELOC(pp) ((pp)->p_state &= ~P_NORELOC) 919 #define PP_CLRMIGRATE(pp) ((pp)->p_state &= ~P_MIGRATE) 920 #define PP_CLRSWAP(pp) ((pp)->p_state &= ~P_SWAP) 921 #define PP_CLRBOOTPAGES(pp) ((pp)->p_state &= ~P_BOOTPAGES) 922 923 /* 924 * Flags for page_t p_toxic, for tracking memory hardware errors. 925 * 926 * These flags are OR'ed into p_toxic with page_settoxic() to track which 927 * error(s) have occurred on a given page. The flags are cleared with 928 * page_clrtoxic(). Both page_settoxic() and page_cleartoxic use atomic 929 * primitives to manipulate the p_toxic field so no other locking is needed. 930 * 931 * When an error occurs on a page, p_toxic is set to record the error. The 932 * error could be a memory error or something else (i.e. a datapath). The Page 933 * Retire mechanism does not try to determine the exact cause of the error; 934 * Page Retire rightly leaves that sort of determination to FMA's Diagnostic 935 * Engine (DE). 936 * 937 * Note that, while p_toxic bits can be set without holding any locks, they 938 * should only be cleared while holding the page exclusively locked. 939 * There is one exception to this, the PR_CAPTURE bit is protected by a mutex 940 * within the page capture logic and thus to set or clear the bit, that mutex 941 * needs to be held. The page does not need to be locked but the page_clrtoxic 942 * function must be used as we need an atomic operation. 943 * Also note that there is what amounts to a hack to prevent recursion with 944 * large pages such that if we are unlocking a page and the PR_CAPTURE bit is 945 * set, we will only try to capture the page if the current threads T_CAPTURING 946 * flag is not set. If the flag is set, the unlock will not try to capture 947 * the page even though the PR_CAPTURE bit is set. 948 * 949 * Pages with PR_UE or PR_FMA flags are retired unconditionally, while pages 950 * with PR_MCE are retired if the system has not retired too many of them. 951 * 952 * A page must be exclusively locked to be retired. Pages can be retired if 953 * they are mapped, modified, or both, as long as they are not marked PR_UE, 954 * since pages with uncorrectable errors cannot be relocated in memory. 955 * Once a page has been successfully retired it is zeroed, attached to the 956 * retired_pages vnode and, finally, PR_RETIRED is set in p_toxic. The other 957 * p_toxic bits are NOT cleared. Pages are not left locked after retiring them 958 * to avoid special case code throughout the kernel; rather, page_*lock() will 959 * fail to lock the page, unless SE_RETIRED is passed as an argument. 960 * 961 * While we have your attention, go take a look at the comments at the 962 * beginning of page_retire.c too. 963 */ 964 #define PR_OK 0x00 /* no problem */ 965 #define PR_MCE 0x01 /* page has seen two or more CEs */ 966 #define PR_UE 0x02 /* page has an unhandled UE */ 967 #define PR_UE_SCRUBBED 0x04 /* page has seen a UE but was cleaned */ 968 #define PR_FMA 0x08 /* A DE wants this page retired */ 969 #define PR_CAPTURE 0x10 /* Generic page capture flag */ 970 #define PR_RESV 0x20 /* Reserved for future use */ 971 #define PR_MSG 0x40 /* message(s) already printed for this page */ 972 #define PR_RETIRED 0x80 /* This page has been retired */ 973 974 #define PR_REASONS (PR_UE | PR_MCE | PR_FMA) 975 #define PR_TOXIC (PR_UE) 976 #define PR_ERRMASK (PR_UE | PR_UE_SCRUBBED | PR_MCE | PR_FMA) 977 #define PR_TOXICFLAGS (0xCF) 978 979 #define PP_RETIRED(pp) ((pp)->p_toxic & PR_RETIRED) 980 #define PP_TOXIC(pp) ((pp)->p_toxic & PR_TOXIC) 981 #define PP_PR_REQ(pp) (((pp)->p_toxic & PR_REASONS) && !PP_RETIRED(pp)) 982 #define PP_PR_NOSHARE(pp) \ 983 ((((pp)->p_toxic & (PR_RETIRED | PR_FMA | PR_UE)) == PR_FMA) && \ 984 !PP_ISKAS(pp)) 985 986 /* 987 * Flags for page_unretire_pp 988 */ 989 #define PR_UNR_FREE 0x1 990 #define PR_UNR_CLEAN 0x2 991 #define PR_UNR_TEMP 0x4 992 993 /* 994 * kpm large page description. 995 * The virtual address range of segkpm is divided into chunks of 996 * kpm_pgsz. Each chunk is controlled by a kpm_page_t. The ushort 997 * is sufficient for 2^^15 * PAGESIZE, so e.g. the maximum kpm_pgsz 998 * for 8K is 256M and 2G for 64K pages. It it kept as small as 999 * possible to save physical memory space. 1000 * 1001 * There are 2 segkpm mapping windows within in the virtual address 1002 * space when we have to prevent VAC alias conflicts. The so called 1003 * Alias window (mappings are always by PAGESIZE) is controlled by 1004 * kp_refcnta. The regular window is controlled by kp_refcnt for the 1005 * normal operation, which is to use the largest available pagesize. 1006 * When VAC alias conflicts are present within a chunk in the regular 1007 * window the large page mapping is broken up into smaller PAGESIZE 1008 * mappings. kp_refcntc is used to control the pages that are invoked 1009 * in the conflict and kp_refcnts holds the active mappings done 1010 * with the small page size. In non vac conflict mode kp_refcntc is 1011 * also used as "go" indication (-1) for the trap level tsbmiss 1012 * handler. 1013 */ 1014 typedef struct kpm_page { 1015 short kp_refcnt; /* pages mapped large */ 1016 short kp_refcnta; /* pages mapped in Alias window */ 1017 short kp_refcntc; /* TL-tsbmiss flag; #vac alias conflict pages */ 1018 short kp_refcnts; /* vac alias: pages mapped small */ 1019 } kpm_page_t; 1020 1021 /* 1022 * Note: khl_lock offset changes must be reflected in sfmmu_asm.s 1023 */ 1024 typedef struct kpm_hlk { 1025 kmutex_t khl_mutex; /* kpm_page mutex */ 1026 uint_t khl_lock; /* trap level tsbmiss handling */ 1027 } kpm_hlk_t; 1028 1029 /* 1030 * kpm small page description. 1031 * When kpm_pgsz is equal to PAGESIZE a smaller representation is used 1032 * to save memory space. Alias range mappings and regular segkpm 1033 * mappings are done in units of PAGESIZE and can share the mapping 1034 * information and the mappings are always distinguishable by their 1035 * virtual address. Other information needed for VAC conflict prevention 1036 * is already available on a per page basis. 1037 * 1038 * The state about how a kpm page is mapped and whether it is ready to go 1039 * is indicated by the following 1 byte kpm_spage structure. This byte is 1040 * split into two 4-bit parts - kp_mapped and kp_mapped_go. 1041 * - kp_mapped == 1 the page is mapped cacheable 1042 * - kp_mapped == 2 the page is mapped non-cacheable 1043 * - kp_mapped_go == 1 the mapping is ready to be dropped in 1044 * - kp_mapped_go == 0 the mapping is not ready to be dropped in. 1045 * When kp_mapped_go == 0, we will have C handler resolve the VAC conflict. 1046 * Otherwise, the assembly tsb miss handler can simply drop in the mapping 1047 * when a tsb miss occurs. 1048 */ 1049 typedef union kpm_spage { 1050 struct { 1051 #ifdef _BIG_ENDIAN 1052 uchar_t mapped_go: 4; /* go or nogo flag */ 1053 uchar_t mapped: 4; /* page mapped small */ 1054 #else 1055 uchar_t mapped: 4; /* page mapped small */ 1056 uchar_t mapped_go: 4; /* go or nogo flag */ 1057 #endif 1058 } kpm_spage_un; 1059 uchar_t kp_mapped_flag; 1060 } kpm_spage_t; 1061 1062 #define kp_mapped kpm_spage_un.mapped 1063 #define kp_mapped_go kpm_spage_un.mapped_go 1064 1065 /* 1066 * Note: kshl_lock offset changes must be reflected in sfmmu_asm.s 1067 */ 1068 typedef struct kpm_shlk { 1069 uint_t kshl_lock; /* trap level tsbmiss handling */ 1070 } kpm_shlk_t; 1071 1072 /* 1073 * Each segment of physical memory is described by a memseg struct. 1074 * Within a segment, memory is considered contiguous. The members 1075 * can be categorized as follows: 1076 * . Platform independent: 1077 * pages, epages, pages_base, pages_end, next, lnext. 1078 * . 64bit only but platform independent: 1079 * kpm_pbase, kpm_nkpmpgs, kpm_pages, kpm_spages. 1080 * . Really platform or mmu specific: 1081 * pagespa, epagespa, nextpa, kpm_pagespa. 1082 * . Mixed: 1083 * msegflags. 1084 */ 1085 struct memseg { 1086 page_t *pages, *epages; /* [from, to] in page array */ 1087 pfn_t pages_base, pages_end; /* [from, to] in page numbers */ 1088 struct memseg *next; /* next segment in list */ 1089 #if defined(__sparc) 1090 struct memseg *lnext; /* next segment in deleted list */ 1091 uint64_t pagespa, epagespa; /* [from, to] page array physical */ 1092 uint64_t nextpa; /* physical next pointer */ 1093 pfn_t kpm_pbase; /* start of kpm range */ 1094 pgcnt_t kpm_nkpmpgs; /* # of kpm_pgsz pages */ 1095 union _mseg_un { 1096 kpm_page_t *kpm_lpgs; /* ptr to kpm_page array */ 1097 kpm_spage_t *kpm_spgs; /* ptr to kpm_spage array */ 1098 } mseg_un; 1099 uint64_t kpm_pagespa; /* physical ptr to kpm (s)pages array */ 1100 uint_t msegflags; /* memseg flags */ 1101 #endif /* __sparc */ 1102 }; 1103 1104 /* memseg union aliases */ 1105 #define kpm_pages mseg_un.kpm_lpgs 1106 #define kpm_spages mseg_un.kpm_spgs 1107 1108 /* msegflags */ 1109 #define MEMSEG_DYNAMIC 0x1 /* DR: memory was added dynamically */ 1110 1111 /* memseg support macros */ 1112 #define MSEG_NPAGES(SEG) ((SEG)->pages_end - (SEG)->pages_base) 1113 1114 /* memseg hash */ 1115 #define MEM_HASH_SHIFT 0x9 1116 #define N_MEM_SLOTS 0x200 /* must be a power of 2 */ 1117 #define MEMSEG_PFN_HASH(pfn) (((pfn)/mhash_per_slot) & (N_MEM_SLOTS - 1)) 1118 1119 /* memseg externals */ 1120 extern struct memseg *memsegs; /* list of memory segments */ 1121 extern ulong_t mhash_per_slot; 1122 extern uint64_t memsegspa; /* memsegs as physical address */ 1123 1124 void build_pfn_hash(); 1125 extern struct memseg *page_numtomemseg_nolock(pfn_t pfnum); 1126 1127 /* 1128 * page capture related info: 1129 * The page capture routines allow us to asynchronously capture given pages 1130 * for the explicit use of the requestor. New requestors can be added by 1131 * explicitly adding themselves to the PC_* flags below and incrementing 1132 * PC_NUM_CALLBACKS as necessary. 1133 * 1134 * Subsystems using page capture must register a callback before attempting 1135 * to capture a page. A duration of -1 will indicate that we will never give 1136 * up while trying to capture a page and will only stop trying to capture the 1137 * given page once we have successfully captured it. Thus the user needs to be 1138 * aware of the behavior of all callers who have a duration of -1. 1139 * 1140 * For now, only /dev/physmem and page retire use the page capture interface 1141 * and only a single request can be outstanding for a given page. Thus, if 1142 * /dev/phsymem wants a page and page retire also wants the same page, only 1143 * the page retire request will be honored until the point in time that the 1144 * page is actually retired, at which point in time, subsequent requests by 1145 * /dev/physmem will succeed if the CAPTURE_GET_RETIRED flag was set. 1146 */ 1147 1148 #define PC_RETIRE (0) 1149 #define PC_PHYSMEM (1) 1150 #define PC_NUM_CALLBACKS (2) 1151 #define PC_MASK ((1 << PC_NUM_CALLBACKS) - 1) 1152 1153 #define CAPTURE_RETIRE (1 << PC_RETIRE) 1154 #define CAPTURE_PHYSMEM (1 << PC_PHYSMEM) 1155 1156 #define CAPTURE_ASYNC (0x0200) 1157 1158 #define CAPTURE_GET_RETIRED (0x1000) 1159 #define CAPTURE_GET_CAGE (0x2000) 1160 1161 struct page_capture_callback { 1162 int cb_active; /* 1 means active, 0 means inactive */ 1163 clock_t duration; /* the length in time that we'll attempt to */ 1164 /* capture this page asynchronously. (in HZ) */ 1165 krwlock_t cb_rwlock; 1166 int (*cb_func)(page_t *, void *, uint_t); /* callback function */ 1167 }; 1168 1169 extern kcondvar_t pc_cv; 1170 1171 void page_capture_register_callback(uint_t index, clock_t duration, 1172 int (*cb_func)(page_t *, void *, uint_t)); 1173 void page_capture_unregister_callback(uint_t index); 1174 int page_trycapture(page_t *pp, uint_t szc, uint_t flags, void *datap); 1175 void page_unlock_capture(page_t *pp); 1176 int page_capture_unretire_pp(page_t *); 1177 1178 extern void memsegs_lock(int); 1179 extern void memsegs_unlock(int); 1180 extern int memsegs_lock_held(void); 1181 extern void memlist_read_lock(void); 1182 extern void memlist_read_unlock(void); 1183 extern void memlist_write_lock(void); 1184 extern void memlist_write_unlock(void); 1185 1186 #ifdef __cplusplus 1187 } 1188 #endif 1189 1190 #endif /* _VM_PAGE_H */ 1191