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 (c) 1986, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright 2021 Oxide Computer Company 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 * PAGE_LLOCK_SIZE is 2 * NCPU, but no smaller than 128. 107 * PAGE_LLOCK_SHIFT is log2(PAGE_LLOCK_SIZE). 108 * 109 * We use ? : instead of #if because <vm/page.h> is included everywhere; 110 * NCPU_P2 is only a constant in the "unix" module. 111 * 112 */ 113 #define PAGE_LLOCK_SHIFT \ 114 ((unsigned)(((2*NCPU_P2) > 128) ? NCPU_LOG2 + 1 : 7)) 115 116 #define PAGE_LLOCK_SIZE (1ul << PAGE_LLOCK_SHIFT) 117 118 /* 119 * The number of low order 0 (or less variable) bits in the page_t address. 120 */ 121 #if defined(__sparc) 122 #define PP_SHIFT 7 123 #else 124 #define PP_SHIFT 6 125 #endif 126 127 /* 128 * pp may be the root of a large page, and many low order bits will be 0. 129 * Shift and XOR multiple times to capture the good bits across the range of 130 * possible page sizes. 131 */ 132 #define PAGE_LLOCK_HASH(pp) \ 133 (((((uintptr_t)(pp) >> PP_SHIFT) ^ \ 134 ((uintptr_t)(pp) >> (PAGE_LLOCK_SHIFT + PP_SHIFT))) ^ \ 135 ((uintptr_t)(pp) >> ((PAGE_LLOCK_SHIFT * 2) + PP_SHIFT)) ^ \ 136 ((uintptr_t)(pp) >> ((PAGE_LLOCK_SHIFT * 3) + PP_SHIFT))) & \ 137 (PAGE_LLOCK_SIZE - 1)) 138 139 #define page_struct_lock(pp) \ 140 mutex_enter(&page_llocks[PAGE_LLOCK_HASH(PP_PAGEROOT(pp))].pad_mutex) 141 #define page_struct_unlock(pp) \ 142 mutex_exit(&page_llocks[PAGE_LLOCK_HASH(PP_PAGEROOT(pp))].pad_mutex) 143 144 #endif /* _KERNEL */ 145 146 #include <sys/t_lock.h> 147 148 struct as; 149 150 /* 151 * Each physical page has a page structure, which is used to maintain 152 * these pages as a cache. A page can be found via a hashed lookup 153 * based on the [vp, offset]. If a page has an [vp, offset] identity, 154 * then it is entered on a doubly linked circular list off the 155 * vnode using the vpnext/vpprev pointers. If the p_free bit 156 * is on, then the page is also on a doubly linked circular free 157 * list using next/prev pointers. If the "p_selock" and "p_iolock" 158 * are held, then the page is currently being read in (exclusive p_selock) 159 * or written back (shared p_selock). In this case, the next/prev pointers 160 * are used to link the pages together for a consecutive i/o request. If 161 * the page is being brought in from its backing store, then other processes 162 * will wait for the i/o to complete before attaching to the page since it 163 * will have an "exclusive" lock. 164 * 165 * Each page structure has the locks described below along with 166 * the fields they protect: 167 * 168 * p_selock This is a per-page shared/exclusive lock that is 169 * used to implement the logical shared/exclusive 170 * lock for each page. The "shared" lock is normally 171 * used in most cases while the "exclusive" lock is 172 * required to destroy or retain exclusive access to 173 * a page (e.g., while reading in pages). The appropriate 174 * lock is always held whenever there is any reference 175 * to a page structure (e.g., during i/o). 176 * (Note that with the addition of the "writer-lock-wanted" 177 * semantics (via SE_EWANTED), threads must not acquire 178 * multiple reader locks or else a deadly embrace will 179 * occur in the following situation: thread 1 obtains a 180 * reader lock; next thread 2 fails to get a writer lock 181 * but specified SE_EWANTED so it will wait by either 182 * blocking (when using page_lock_es) or spinning while 183 * retrying (when using page_try_reclaim_lock) until the 184 * reader lock is released; then thread 1 attempts to 185 * get another reader lock but is denied due to 186 * SE_EWANTED being set, and now both threads are in a 187 * deadly embrace.) 188 * 189 * p_hash 190 * p_vnode 191 * p_offset 192 * 193 * p_free 194 * p_age 195 * 196 * p_iolock This is a binary semaphore lock that provides 197 * exclusive access to the i/o list links in each 198 * page structure. It is always held while the page 199 * is on an i/o list (i.e., involved in i/o). That is, 200 * even though a page may be only `shared' locked 201 * while it is doing a write, the following fields may 202 * change anyway. Normally, the page must be 203 * `exclusively' locked to change anything in it. 204 * 205 * p_next 206 * p_prev 207 * 208 * The following fields are protected by the global page_llocks[]: 209 * 210 * p_lckcnt 211 * p_cowcnt 212 * 213 * The following lists are protected by the global page_freelock: 214 * 215 * page_cachelist 216 * page_freelist 217 * 218 * The following, for our purposes, are protected by 219 * the global freemem_lock: 220 * 221 * freemem 222 * freemem_wait 223 * freemem_cv 224 * 225 * The following fields are protected by hat layer lock(s). When a page 226 * structure is not mapped and is not associated with a vnode (after a call 227 * to page_hashout() for example) the p_nrm field may be modified with out 228 * holding the hat layer lock: 229 * 230 * p_nrm 231 * p_mapping 232 * p_share 233 * 234 * The following field is file system dependent. How it is used and 235 * the locking strategies applied are up to the individual file system 236 * implementation. 237 * 238 * p_fsdata 239 * 240 * The page structure is used to represent and control the system's 241 * physical pages. There is one instance of the structure for each 242 * page that is not permenately allocated. For example, the pages that 243 * hold the page structures are permanently held by the kernel 244 * and hence do not need page structures to track them. The array 245 * of page structures is allocated early on in the kernel's life and 246 * is based on the amount of available physical memory. 247 * 248 * Each page structure may simultaneously appear on several linked lists. 249 * The lists are: hash list, free or in i/o list, and a vnode's page list. 250 * Each type of list is protected by a different group of mutexes as described 251 * below: 252 * 253 * The hash list is used to quickly find a page when the page's vnode and 254 * offset within the vnode are known. Each page that is hashed is 255 * connected via the `p_hash' field. The anchor for each hash is in the 256 * array `page_hash'. An array of mutexes, `ph_mutex', protects the 257 * lists anchored by page_hash[]. To either search or modify a given hash 258 * list, the appropriate mutex in the ph_mutex array must be held. 259 * 260 * The free list contains pages that are `free to be given away'. For 261 * efficiency reasons, pages on this list are placed in two catagories: 262 * pages that are still associated with a vnode, and pages that are not 263 * associated with a vnode. Free pages always have their `p_free' bit set, 264 * free pages that are still associated with a vnode also have their 265 * `p_age' bit set. Pages on the free list are connected via their 266 * `p_next' and `p_prev' fields. When a page is involved in some sort 267 * of i/o, it is not free and these fields may be used to link associated 268 * pages together. At the moment, the free list is protected by a 269 * single mutex `page_freelock'. The list of free pages still associated 270 * with a vnode is anchored by `page_cachelist' while other free pages 271 * are anchored in architecture dependent ways (to handle page coloring etc.). 272 * 273 * Pages associated with a given vnode appear on a list anchored in the 274 * vnode by the `v_pages' field. They are linked together with 275 * `p_vpnext' and `p_vpprev'. The field `p_offset' contains a page's 276 * offset within the vnode. The pages on this list are not kept in 277 * offset order. These lists, in a manner similar to the hash lists, 278 * are protected by an array of mutexes called `vph_hash'. Before 279 * searching or modifying this chain the appropriate mutex in the 280 * vph_hash[] array must be held. 281 * 282 * Again, each of the lists that a page can appear on is protected by a 283 * mutex. Before reading or writing any of the fields comprising the 284 * list, the appropriate lock must be held. These list locks should only 285 * be held for very short intervals. 286 * 287 * In addition to the list locks, each page structure contains a 288 * shared/exclusive lock that protects various fields within it. 289 * To modify one of these fields, the `p_selock' must be exclusively held. 290 * To read a field with a degree of certainty, the lock must be at least 291 * held shared. 292 * 293 * Removing a page structure from one of the lists requires holding 294 * the appropriate list lock and the page's p_selock. A page may be 295 * prevented from changing identity, being freed, or otherwise modified 296 * by acquiring p_selock shared. 297 * 298 * To avoid deadlocks, a strict locking protocol must be followed. Basically 299 * there are two cases: In the first case, the page structure in question 300 * is known ahead of time (e.g., when the page is to be added or removed 301 * from a list). In the second case, the page structure is not known and 302 * must be found by searching one of the lists. 303 * 304 * When adding or removing a known page to one of the lists, first the 305 * page must be exclusively locked (since at least one of its fields 306 * will be modified), second the lock protecting the list must be acquired, 307 * third the page inserted or deleted, and finally the list lock dropped. 308 * 309 * The more interesting case occures when the particular page structure 310 * is not known ahead of time. For example, when a call is made to 311 * page_lookup(), it is not known if a page with the desired (vnode and 312 * offset pair) identity exists. So the appropriate mutex in ph_mutex is 313 * acquired, the hash list searched, and if the desired page is found 314 * an attempt is made to lock it. The attempt to acquire p_selock must 315 * not block while the hash list lock is held. A deadlock could occure 316 * if some other process was trying to remove the page from the list. 317 * The removing process (following the above protocol) would have exclusively 318 * locked the page, and be spinning waiting to acquire the lock protecting 319 * the hash list. Since the searching process holds the hash list lock 320 * and is waiting to acquire the page lock, a deadlock occurs. 321 * 322 * The proper scheme to follow is: first, lock the appropriate list, 323 * search the list, and if the desired page is found either use 324 * page_trylock() (which will not block) or pass the address of the 325 * list lock to page_lock(). If page_lock() can not acquire the page's 326 * lock, it will drop the list lock before going to sleep. page_lock() 327 * returns a value to indicate if the list lock was dropped allowing the 328 * calling program to react appropriately (i.e., retry the operation). 329 * 330 * If the list lock was dropped before the attempt at locking the page 331 * was made, checks would have to be made to ensure that the page had 332 * not changed identity before its lock was obtained. This is because 333 * the interval between dropping the list lock and acquiring the page 334 * lock is indeterminate. 335 * 336 * In addition, when both a hash list lock (ph_mutex[]) and a vnode list 337 * lock (vph_mutex[]) are needed, the hash list lock must be acquired first. 338 * The routine page_hashin() is a good example of this sequence. 339 * This sequence is ASSERTed by checking that the vph_mutex[] is not held 340 * just before each acquisition of one of the mutexs in ph_mutex[]. 341 * 342 * So, as a quick summary: 343 * 344 * pse_mutex[]'s protect the p_selock and p_cv fields. 345 * 346 * p_selock protects the p_free, p_age, p_vnode, p_offset and p_hash, 347 * 348 * ph_mutex[]'s protect the page_hash[] array and its chains. 349 * 350 * vph_mutex[]'s protect the v_pages field and the vp page chains. 351 * 352 * First lock the page, then the hash chain, then the vnode chain. When 353 * this is not possible `trylocks' must be used. Sleeping while holding 354 * any of these mutexes (p_selock is not a mutex) is not allowed. 355 * 356 * 357 * field reading writing ordering 358 * ====================================================================== 359 * p_vnode p_selock(E,S) p_selock(E) 360 * p_offset 361 * p_free 362 * p_age 363 * ===================================================================== 364 * p_hash p_selock(E,S) p_selock(E) && p_selock, ph_mutex 365 * ph_mutex[] 366 * ===================================================================== 367 * p_vpnext p_selock(E,S) p_selock(E) && p_selock, vph_mutex 368 * p_vpprev vph_mutex[] 369 * ===================================================================== 370 * When the p_free bit is set: 371 * 372 * p_next p_selock(E,S) p_selock(E) && p_selock, 373 * p_prev page_freelock page_freelock 374 * 375 * When the p_free bit is not set: 376 * 377 * p_next p_selock(E,S) p_selock(E) && p_selock, p_iolock 378 * p_prev p_iolock 379 * ===================================================================== 380 * p_selock pse_mutex[] pse_mutex[] can`t acquire any 381 * p_cv other mutexes or 382 * sleep while holding 383 * this lock. 384 * ===================================================================== 385 * p_lckcnt p_selock(E,S) p_selock(E) 386 * OR 387 * p_selock(S) && 388 * page_llocks[] 389 * p_cowcnt 390 * ===================================================================== 391 * p_nrm hat layer lock hat layer lock 392 * p_mapping 393 * p_pagenum 394 * ===================================================================== 395 * 396 * where: 397 * E----> exclusive version of p_selock. 398 * S----> shared version of p_selock. 399 * 400 * 401 * Global data structures and variable: 402 * 403 * field reading writing ordering 404 * ===================================================================== 405 * page_hash[] ph_mutex[] ph_mutex[] can hold this lock 406 * before acquiring 407 * a vph_mutex or 408 * pse_mutex. 409 * ===================================================================== 410 * vp->v_pages vph_mutex[] vph_mutex[] can only acquire 411 * a pse_mutex while 412 * holding this lock. 413 * ===================================================================== 414 * page_cachelist page_freelock page_freelock can't acquire any 415 * page_freelist page_freelock page_freelock 416 * ===================================================================== 417 * freemem freemem_lock freemem_lock can't acquire any 418 * freemem_wait other mutexes while 419 * freemem_cv holding this mutex. 420 * ===================================================================== 421 * 422 * Page relocation, PG_NORELOC and P_NORELOC. 423 * 424 * Pages may be relocated using the page_relocate() interface. Relocation 425 * involves moving the contents and identity of a page to another, free page. 426 * To relocate a page, the SE_EXCL lock must be obtained. The way to prevent 427 * a page from being relocated is to hold the SE_SHARED lock (the SE_EXCL 428 * lock must not be held indefinitely). If the page is going to be held 429 * SE_SHARED indefinitely, then the PG_NORELOC hint should be passed 430 * to page_create_va so that pages that are prevented from being relocated 431 * can be managed differently by the platform specific layer. 432 * 433 * Pages locked in memory using page_pp_lock (p_lckcnt/p_cowcnt != 0) 434 * are guaranteed to be held in memory, but can still be relocated 435 * providing the SE_EXCL lock can be obtained. 436 * 437 * The P_NORELOC bit in the page_t.p_state field is provided for use by 438 * the platform specific code in managing pages when the PG_NORELOC 439 * hint is used. 440 * 441 * Memory delete and page locking. 442 * 443 * The set of all usable pages is managed using the global page list as 444 * implemented by the memseg structure defined below. When memory is added 445 * or deleted this list changes. Additions to this list guarantee that the 446 * list is never corrupt. In order to avoid the necessity of an additional 447 * lock to protect against failed accesses to the memseg being deleted and, 448 * more importantly, the page_ts, the memseg structure is never freed and the 449 * page_t virtual address space is remapped to a page (or pages) of 450 * zeros. If a page_t is manipulated while it is p_selock'd, or if it is 451 * locked indirectly via a hash or freelist lock, it is not possible for 452 * memory delete to collect the page and so that part of the page list is 453 * prevented from being deleted. If the page is referenced outside of one 454 * of these locks, it is possible for the page_t being referenced to be 455 * deleted. Examples of this are page_t pointers returned by 456 * page_numtopp_nolock, page_first and page_next. Providing the page_t 457 * is re-checked after taking the p_selock (for p_vnode != NULL), the 458 * remapping to the zero pages will be detected. 459 * 460 * 461 * Page size (p_szc field) and page locking. 462 * 463 * p_szc field of free pages is changed by free list manager under freelist 464 * locks and is of no concern to the rest of VM subsystem. 465 * 466 * p_szc changes of allocated anonymous (swapfs) can only be done only after 467 * exclusively locking all constituent pages and calling hat_pageunload() on 468 * each of them. To prevent p_szc changes of non free anonymous (swapfs) large 469 * pages it's enough to either lock SHARED any of constituent pages or prevent 470 * hat_pageunload() by holding hat level lock that protects mapping lists (this 471 * method is for hat code only) 472 * 473 * To increase (promote) p_szc of allocated non anonymous file system pages 474 * one has to first lock exclusively all involved constituent pages and call 475 * hat_pageunload() on each of them. To prevent p_szc promote it's enough to 476 * either lock SHARED any of constituent pages that will be needed to make a 477 * large page or prevent hat_pageunload() by holding hat level lock that 478 * protects mapping lists (this method is for hat code only). 479 * 480 * To decrease (demote) p_szc of an allocated non anonymous file system large 481 * page one can either use the same method as used for changeing p_szc of 482 * anonymous large pages or if it's not possible to lock all constituent pages 483 * exclusively a different method can be used. In the second method one only 484 * has to exclusively lock one of constituent pages but then one has to 485 * acquire further locks by calling page_szc_lock() and 486 * hat_page_demote(). hat_page_demote() acquires hat level locks and then 487 * demotes the page. This mechanism relies on the fact that any code that 488 * needs to prevent p_szc of a file system large page from changeing either 489 * locks all constituent large pages at least SHARED or locks some pages at 490 * least SHARED and calls page_szc_lock() or uses hat level page locks. 491 * Demotion using this method is implemented by page_demote_vp_pages(). 492 * Please see comments in front of page_demote_vp_pages(), hat_page_demote() 493 * and page_szc_lock() for more details. 494 * 495 * Lock order: p_selock, page_szc_lock, ph_mutex/vph_mutex/freelist, 496 * hat level locks. 497 */ 498 499 typedef struct page { 500 u_offset_t p_offset; /* offset into vnode for this page */ 501 struct vnode *p_vnode; /* vnode that this page is named by */ 502 selock_t p_selock; /* shared/exclusive lock on the page */ 503 #if defined(_LP64) 504 uint_t p_vpmref; /* vpm ref - index of the vpmap_t */ 505 #endif 506 struct page *p_hash; /* hash by [vnode, offset] */ 507 struct page *p_vpnext; /* next page in vnode list */ 508 struct page *p_vpprev; /* prev page in vnode list */ 509 struct page *p_next; /* next page in free/intrans lists */ 510 struct page *p_prev; /* prev page in free/intrans lists */ 511 ushort_t p_lckcnt; /* number of locks on page data */ 512 ushort_t p_cowcnt; /* number of copy on write lock */ 513 kcondvar_t p_cv; /* page struct's condition var */ 514 kcondvar_t p_io_cv; /* for iolock */ 515 uchar_t p_iolock_state; /* replaces p_iolock */ 516 volatile uchar_t p_szc; /* page size code */ 517 uchar_t p_fsdata; /* file system dependent byte */ 518 uchar_t p_state; /* p_free, p_noreloc */ 519 uchar_t p_nrm; /* non-cache, ref, mod readonly bits */ 520 #if defined(__sparc) 521 uchar_t p_vcolor; /* virtual color */ 522 #else 523 uchar_t p_embed; /* x86 - changes p_mapping & p_index */ 524 #endif 525 uchar_t p_index; /* MPSS mapping info. Not used on x86 */ 526 uchar_t p_toxic; /* page has an unrecoverable error */ 527 void *p_mapping; /* hat specific translation info */ 528 pfn_t p_pagenum; /* physical page number */ 529 530 uint_t p_share; /* number of translations */ 531 #if defined(_LP64) 532 uint_t p_sharepad; /* pad for growing p_share */ 533 #endif 534 uint_t p_slckcnt; /* number of softlocks */ 535 #if defined(__sparc) 536 uint_t p_kpmref; /* number of kpm mapping sharers */ 537 struct kpme *p_kpmelist; /* kpm specific mapping info */ 538 #else 539 /* index of entry in p_map when p_embed is set */ 540 uint_t p_mlentry; 541 #endif 542 #if defined(_LP64) 543 kmutex_t p_ilock; /* protects p_vpmref */ 544 #else 545 uint64_t p_msresv_2; /* page allocation debugging */ 546 #endif 547 } page_t; 548 549 550 typedef page_t devpage_t; 551 #define devpage page 552 553 #define PAGE_LOCK_MAXIMUM \ 554 ((1 << (sizeof (((page_t *)0)->p_lckcnt) * NBBY)) - 1) 555 556 #define PAGE_SLOCK_MAXIMUM UINT_MAX 557 558 /* 559 * Page hash table is a power-of-two in size, externally chained 560 * through the hash field. PAGE_HASHAVELEN is the average length 561 * desired for this chain, from which the size of the page_hash 562 * table is derived at boot time and stored in the kernel variable 563 * page_hashsz. In the hash function it is given by PAGE_HASHSZ. 564 * 565 * PAGE_HASH_FUNC returns an index into the page_hash[] array. This 566 * index is also used to derive the mutex that protects the chain. 567 * 568 * In constructing the hash function, first we dispose of unimportant bits 569 * (page offset from "off" and the low 3 bits of "vp" which are zero for 570 * struct alignment). Then shift and sum the remaining bits a couple times 571 * in order to get as many source bits from the two source values into the 572 * resulting hashed value. Note that this will perform quickly, since the 573 * shifting/summing are fast register to register operations with no additional 574 * memory references). 575 * 576 * PH_SHIFT_SIZE is the amount to use for the successive shifts in the hash 577 * function below. The actual value is LOG2(PH_TABLE_SIZE), so that as many 578 * bits as possible will filter thru PAGE_HASH_FUNC() and PAGE_HASH_MUTEX(). 579 * 580 * We use ? : instead of #if because <vm/page.h> is included everywhere; 581 * NCPU maps to a global variable outside of the "unix" module. 582 */ 583 #if defined(_LP64) 584 #define PH_SHIFT_SIZE ((NCPU < 4) ? 7 : (NCPU_LOG2 + 1)) 585 #else /* 32 bits */ 586 #define PH_SHIFT_SIZE ((NCPU < 4) ? 4 : 7) 587 #endif /* _LP64 */ 588 589 #define PH_TABLE_SIZE (1ul << PH_SHIFT_SIZE) 590 591 /* 592 * 593 * We take care to get as much randomness as possible from both the vp and 594 * the offset. Workloads can have few vnodes with many offsets, many vnodes 595 * with few offsets or a moderate mix of both. This hash should perform 596 * equally well for each of these possibilities and for all types of memory 597 * allocations. 598 * 599 * vnodes representing files are created over a long period of time and 600 * have good variation in the upper vp bits, and the right shifts below 601 * capture these bits. However, swap vnodes are created quickly in a 602 * narrow vp* range. Refer to comments at swap_alloc: vnum has exactly 603 * AN_VPSHIFT bits, so the kmem_alloc'd vnode addresses have approximately 604 * AN_VPSHIFT bits of variation above their VNODE_ALIGN low order 0 bits. 605 * Spread swap vnodes widely in the hash table by XOR'ing a term with the 606 * vp bits of variation left shifted to the top of the range. 607 */ 608 609 #define PAGE_HASHSZ page_hashsz 610 #define PAGE_HASHAVELEN 4 611 #define PAGE_HASH_FUNC(vp, off) \ 612 (((((uintptr_t)(off) >> PAGESHIFT) ^ \ 613 ((uintptr_t)(off) >> (PAGESHIFT + PH_SHIFT_SIZE))) ^ \ 614 (((uintptr_t)(vp) >> 3) ^ \ 615 ((uintptr_t)(vp) >> (3 + PH_SHIFT_SIZE)) ^ \ 616 ((uintptr_t)(vp) >> (3 + 2 * PH_SHIFT_SIZE)) ^ \ 617 ((uintptr_t)(vp) << \ 618 (page_hashsz_shift - AN_VPSHIFT - VNODE_ALIGN_LOG2)))) & \ 619 (PAGE_HASHSZ - 1)) 620 621 #ifdef _KERNEL 622 623 /* 624 * The page hash value is re-hashed to an index for the ph_mutex array. 625 * 626 * For 64 bit kernels, the mutex array is padded out to prevent false 627 * sharing of cache sub-blocks (64 bytes) of adjacent mutexes. 628 * 629 * For 32 bit kernels, we don't want to waste kernel address space with 630 * padding, so instead we rely on the hash function to introduce skew of 631 * adjacent vnode/offset indexes (the left shift part of the hash function). 632 * Since sizeof (kmutex_t) is 8, we shift an additional 3 to skew to a different 633 * 64 byte sub-block. 634 */ 635 extern pad_mutex_t ph_mutex[]; 636 637 #define PAGE_HASH_MUTEX(x) \ 638 &(ph_mutex[((x) ^ ((x) >> PH_SHIFT_SIZE) + ((x) << 3)) & \ 639 (PH_TABLE_SIZE - 1)].pad_mutex) 640 641 /* 642 * Flags used while creating pages. 643 */ 644 #define PG_EXCL 0x0001 645 #define PG_WAIT 0x0002 /* Blocking memory allocations */ 646 #define PG_PHYSCONTIG 0x0004 /* NOT SUPPORTED */ 647 #define PG_MATCH_COLOR 0x0008 /* SUPPORTED by free list routines */ 648 #define PG_NORELOC 0x0010 /* Non-relocatable alloc hint. */ 649 /* Page must be PP_ISNORELOC */ 650 #define PG_PANIC 0x0020 /* system will panic if alloc fails */ 651 #define PG_PUSHPAGE 0x0040 /* alloc may use reserve */ 652 #define PG_LOCAL 0x0080 /* alloc from given lgrp only */ 653 #define PG_NORMALPRI 0x0100 /* PG_WAIT like priority, but */ 654 /* non-blocking */ 655 /* 656 * When p_selock has the SE_EWANTED bit set, threads waiting for SE_EXCL 657 * access are given priority over all other waiting threads. 658 */ 659 #define SE_EWANTED 0x40000000 660 #define PAGE_LOCKED(pp) (((pp)->p_selock & ~SE_EWANTED) != 0) 661 #define PAGE_SHARED(pp) (((pp)->p_selock & ~SE_EWANTED) > 0) 662 #define PAGE_EXCL(pp) ((pp)->p_selock < 0) 663 #define PAGE_LOCKED_SE(pp, se) \ 664 ((se) == SE_EXCL ? PAGE_EXCL(pp) : PAGE_SHARED(pp)) 665 666 extern long page_hashsz; 667 extern unsigned int page_hashsz_shift; 668 extern page_t **page_hash; 669 670 extern pad_mutex_t page_llocks[]; /* page logical lock mutex */ 671 extern kmutex_t freemem_lock; /* freemem lock */ 672 673 extern pgcnt_t total_pages; /* total pages in the system */ 674 675 /* 676 * Variables controlling locking of physical memory. 677 */ 678 extern pgcnt_t pages_pp_maximum; /* tuning: lock + claim <= max */ 679 extern void init_pages_pp_maximum(void); 680 681 struct lgrp; 682 683 /* page_list_{add,sub} flags */ 684 685 /* which list */ 686 #define PG_FREE_LIST 0x0001 687 #define PG_CACHE_LIST 0x0002 688 689 /* where on list */ 690 #define PG_LIST_TAIL 0x0010 691 #define PG_LIST_HEAD 0x0020 692 693 /* called from */ 694 #define PG_LIST_ISINIT 0x1000 695 696 /* 697 * Page frame operations. 698 */ 699 page_t *page_lookup(struct vnode *, u_offset_t, se_t); 700 page_t *page_lookup_create(struct vnode *, u_offset_t, se_t, page_t *, 701 spgcnt_t *, int); 702 page_t *page_lookup_nowait(struct vnode *, u_offset_t, se_t); 703 page_t *page_find(struct vnode *, u_offset_t); 704 page_t *page_exists(struct vnode *, u_offset_t); 705 int page_exists_physcontig(vnode_t *, u_offset_t, uint_t, page_t *[]); 706 int page_exists_forreal(struct vnode *, u_offset_t, uint_t *); 707 void page_needfree(spgcnt_t); 708 page_t *page_create(struct vnode *, u_offset_t, size_t, uint_t); 709 int page_alloc_pages(struct vnode *, struct seg *, caddr_t, page_t **, 710 page_t **, uint_t, int, int); 711 page_t *page_create_va_large(vnode_t *vp, u_offset_t off, size_t bytes, 712 uint_t flags, struct seg *seg, caddr_t vaddr, void *arg); 713 page_t *page_create_va(struct vnode *, u_offset_t, size_t, uint_t, 714 struct seg *, caddr_t); 715 int page_create_wait(pgcnt_t npages, uint_t flags); 716 void page_create_putback(spgcnt_t npages); 717 void page_free(page_t *, int); 718 void page_free_at_startup(page_t *); 719 void page_free_pages(page_t *); 720 void free_vp_pages(struct vnode *, u_offset_t, size_t); 721 int page_reclaim(page_t *, kmutex_t *); 722 int page_reclaim_pages(page_t *, kmutex_t *, uint_t); 723 void page_destroy(page_t *, int); 724 void page_destroy_pages(page_t *); 725 void page_destroy_free(page_t *); 726 void page_rename(page_t *, struct vnode *, u_offset_t); 727 int page_hashin(page_t *, struct vnode *, u_offset_t, kmutex_t *); 728 void page_hashout(page_t *, kmutex_t *); 729 int page_num_hashin(pfn_t, struct vnode *, u_offset_t); 730 void page_add(page_t **, page_t *); 731 void page_add_common(page_t **, page_t *); 732 void page_sub(page_t **, page_t *); 733 void page_sub_common(page_t **, page_t *); 734 page_t *page_get_freelist(struct vnode *, u_offset_t, struct seg *, 735 caddr_t, size_t, uint_t, struct lgrp *); 736 737 page_t *page_get_cachelist(struct vnode *, u_offset_t, struct seg *, 738 caddr_t, uint_t, struct lgrp *); 739 #if defined(__i386) || defined(__amd64) 740 int page_chk_freelist(uint_t); 741 #endif 742 void page_list_add(page_t *, int); 743 void page_boot_demote(page_t *); 744 void page_promote_size(page_t *, uint_t); 745 void page_list_add_pages(page_t *, int); 746 void page_list_sub(page_t *, int); 747 void page_list_sub_pages(page_t *, uint_t); 748 void page_list_xfer(page_t *, int, int); 749 void page_list_break(page_t **, page_t **, size_t); 750 void page_list_concat(page_t **, page_t **); 751 void page_vpadd(page_t **, page_t *); 752 void page_vpsub(page_t **, page_t *); 753 int page_lock(page_t *, se_t, kmutex_t *, reclaim_t); 754 int page_lock_es(page_t *, se_t, kmutex_t *, reclaim_t, int); 755 void page_lock_clr_exclwanted(page_t *); 756 int page_trylock(page_t *, se_t); 757 int page_try_reclaim_lock(page_t *, se_t, int); 758 int page_tryupgrade(page_t *); 759 void page_downgrade(page_t *); 760 void page_unlock(page_t *); 761 void page_unlock_nocapture(page_t *); 762 void page_lock_delete(page_t *); 763 int page_deleted(page_t *); 764 int page_pp_lock(page_t *, int, int); 765 void page_pp_unlock(page_t *, int, int); 766 int page_xresv(pgcnt_t, uint_t, int (*)(void)); 767 int page_resv(pgcnt_t, uint_t); 768 void page_unresv(pgcnt_t); 769 void page_pp_useclaim(page_t *, page_t *, uint_t); 770 int page_addclaim(page_t *); 771 int page_subclaim(page_t *); 772 int page_addclaim_pages(page_t **); 773 int page_subclaim_pages(page_t **); 774 pfn_t page_pptonum(page_t *); 775 page_t *page_numtopp(pfn_t, se_t); 776 page_t *page_numtopp_noreclaim(pfn_t, se_t); 777 page_t *page_numtopp_nolock(pfn_t); 778 page_t *page_numtopp_nowait(pfn_t, se_t); 779 page_t *page_first(); 780 page_t *page_next(page_t *); 781 page_t *page_list_next(page_t *); 782 page_t *page_nextn(page_t *, ulong_t); 783 page_t *page_next_scan_init(void **); 784 page_t *page_next_scan_large(page_t *, ulong_t *, void **); 785 void prefetch_page_r(void *); 786 int ppcopy(page_t *, page_t *); 787 void page_relocate_hash(page_t *, page_t *); 788 void pagezero(page_t *, uint_t, uint_t); 789 void pagescrub(page_t *, uint_t, uint_t); 790 void page_io_lock(page_t *); 791 void page_io_unlock(page_t *); 792 int page_io_trylock(page_t *); 793 int page_iolock_assert(page_t *); 794 void page_iolock_init(page_t *); 795 void page_io_wait(page_t *); 796 int page_io_locked(page_t *); 797 pgcnt_t page_busy(int); 798 void page_lock_init(void); 799 ulong_t page_share_cnt(page_t *); 800 int page_isshared(page_t *); 801 int page_isfree(page_t *); 802 int page_isref(page_t *); 803 int page_ismod(page_t *); 804 int page_release(page_t *, int); 805 void page_retire_init(void); 806 int page_retire(uint64_t, uchar_t); 807 int page_retire_check(uint64_t, uint64_t *); 808 int page_unretire(uint64_t); 809 int page_unretire_pp(page_t *, int); 810 void page_tryretire(page_t *); 811 void page_retire_mdboot(); 812 uint64_t page_retire_pend_count(void); 813 uint64_t page_retire_pend_kas_count(void); 814 void page_retire_incr_pend_count(void *); 815 void page_retire_decr_pend_count(void *); 816 void page_clrtoxic(page_t *, uchar_t); 817 void page_settoxic(page_t *, uchar_t); 818 819 int page_reclaim_mem(pgcnt_t, pgcnt_t, int); 820 821 void page_set_props(page_t *, uint_t); 822 void page_clr_all_props(page_t *); 823 int page_clear_lck_cow(page_t *, int); 824 825 kmutex_t *page_vnode_mutex(struct vnode *); 826 kmutex_t *page_se_mutex(struct page *); 827 kmutex_t *page_szc_lock(struct page *); 828 int page_szc_lock_assert(struct page *pp); 829 830 /* 831 * Page relocation interfaces. page_relocate() is generic. 832 * page_get_replacement_page() is provided by the PSM. 833 * page_free_replacement_page() is generic. 834 */ 835 int group_page_trylock(page_t *, se_t); 836 void group_page_unlock(page_t *); 837 int page_relocate(page_t **, page_t **, int, int, spgcnt_t *, struct lgrp *); 838 int do_page_relocate(page_t **, page_t **, int, spgcnt_t *, struct lgrp *); 839 page_t *page_get_replacement_page(page_t *, struct lgrp *, uint_t); 840 void page_free_replacement_page(page_t *); 841 int page_relocate_cage(page_t **, page_t **); 842 843 int page_try_demote_pages(page_t *); 844 int page_try_demote_free_pages(page_t *); 845 void page_demote_free_pages(page_t *); 846 847 struct anon_map; 848 849 void page_mark_migrate(struct seg *, caddr_t, size_t, struct anon_map *, 850 ulong_t, vnode_t *, u_offset_t, int); 851 void page_migrate(struct seg *, caddr_t, page_t **, pgcnt_t); 852 853 /* 854 * Tell the PIM we are adding physical memory 855 */ 856 void add_physmem(page_t *, size_t, pfn_t); 857 void add_physmem_cb(page_t *, pfn_t); /* callback for page_t part */ 858 859 /* 860 * hw_page_array[] is configured with hardware supported page sizes by 861 * platform specific code. 862 */ 863 typedef struct { 864 size_t hp_size; 865 uint_t hp_shift; 866 uint_t hp_colors; 867 pgcnt_t hp_pgcnt; /* base pagesize cnt */ 868 } hw_pagesize_t; 869 870 extern hw_pagesize_t hw_page_array[]; 871 extern uint_t page_coloring_shift; 872 extern uint_t page_colors_mask; 873 extern int cpu_page_colors; 874 extern uint_t colorequiv; 875 extern uchar_t colorequivszc[]; 876 877 uint_t page_num_pagesizes(void); 878 uint_t page_num_user_pagesizes(int); 879 size_t page_get_pagesize(uint_t); 880 size_t page_get_user_pagesize(uint_t n); 881 pgcnt_t page_get_pagecnt(uint_t); 882 uint_t page_get_shift(uint_t); 883 int page_szc(size_t); 884 int page_szc_user_filtered(size_t); 885 886 /* page_get_replacement page flags */ 887 #define PGR_SAMESZC 0x1 /* only look for page size same as orig */ 888 #define PGR_NORELOC 0x2 /* allocate a P_NORELOC page */ 889 890 /* 891 * macros for "masked arithmetic" 892 * The purpose is to step through all combinations of a set of bits while 893 * keeping some other bits fixed. Fixed bits need not be contiguous. The 894 * variable bits need not be contiguous either, or even right aligned. The 895 * trick is to set all fixed bits to 1, then increment, then restore the 896 * fixed bits. If incrementing causes a carry from a low bit position, the 897 * carry propagates thru the fixed bits, because they are temporarily set to 1. 898 * v is the value 899 * i is the increment 900 * eq_mask defines the fixed bits 901 * mask limits the size of the result 902 */ 903 #define ADD_MASKED(v, i, eq_mask, mask) \ 904 (((((v) | (eq_mask)) + (i)) & (mask) & ~(eq_mask)) | ((v) & (eq_mask))) 905 906 /* 907 * convenience macro which increments by 1 908 */ 909 #define INC_MASKED(v, eq_mask, mask) ADD_MASKED(v, 1, eq_mask, mask) 910 911 #endif /* _KERNEL */ 912 913 /* 914 * Constants used for the p_iolock_state 915 */ 916 #define PAGE_IO_INUSE 0x1 917 #define PAGE_IO_WANTED 0x2 918 919 /* 920 * Constants used for page_release status 921 */ 922 #define PGREL_NOTREL 0x1 923 #define PGREL_CLEAN 0x2 924 #define PGREL_MOD 0x3 925 926 /* 927 * The p_state field holds what used to be the p_age and p_free 928 * bits. These fields are protected by p_selock (see above). 929 */ 930 #define P_FREE 0x80 /* Page on free list */ 931 #define P_NORELOC 0x40 /* Page is non-relocatable */ 932 #define P_MIGRATE 0x20 /* Migrate page on next touch */ 933 #define P_SWAP 0x10 /* belongs to vnode that is V_ISSWAP */ 934 #define P_BOOTPAGES 0x08 /* member of bootpages list */ 935 #define P_RAF 0x04 /* page retired at free */ 936 937 #define PP_ISFREE(pp) ((pp)->p_state & P_FREE) 938 #define PP_ISAGED(pp) (((pp)->p_state & P_FREE) && \ 939 ((pp)->p_vnode == NULL)) 940 #define PP_ISNORELOC(pp) ((pp)->p_state & P_NORELOC) 941 #define PP_ISKAS(pp) (VN_ISKAS((pp)->p_vnode)) 942 #define PP_ISNORELOCKERNEL(pp) (PP_ISNORELOC(pp) && PP_ISKAS(pp)) 943 #define PP_ISMIGRATE(pp) ((pp)->p_state & P_MIGRATE) 944 #define PP_ISSWAP(pp) ((pp)->p_state & P_SWAP) 945 #define PP_ISBOOTPAGES(pp) ((pp)->p_state & P_BOOTPAGES) 946 #define PP_ISRAF(pp) ((pp)->p_state & P_RAF) 947 948 #define PP_SETFREE(pp) ((pp)->p_state = ((pp)->p_state & ~P_MIGRATE) \ 949 | P_FREE) 950 #define PP_SETAGED(pp) ASSERT(PP_ISAGED(pp)) 951 #define PP_SETNORELOC(pp) ((pp)->p_state |= P_NORELOC) 952 #define PP_SETMIGRATE(pp) ((pp)->p_state |= P_MIGRATE) 953 #define PP_SETSWAP(pp) ((pp)->p_state |= P_SWAP) 954 #define PP_SETBOOTPAGES(pp) ((pp)->p_state |= P_BOOTPAGES) 955 #define PP_SETRAF(pp) ((pp)->p_state |= P_RAF) 956 957 #define PP_CLRFREE(pp) ((pp)->p_state &= ~P_FREE) 958 #define PP_CLRAGED(pp) ASSERT(!PP_ISAGED(pp)) 959 #define PP_CLRNORELOC(pp) ((pp)->p_state &= ~P_NORELOC) 960 #define PP_CLRMIGRATE(pp) ((pp)->p_state &= ~P_MIGRATE) 961 #define PP_CLRSWAP(pp) ((pp)->p_state &= ~P_SWAP) 962 #define PP_CLRBOOTPAGES(pp) ((pp)->p_state &= ~P_BOOTPAGES) 963 #define PP_CLRRAF(pp) ((pp)->p_state &= ~P_RAF) 964 965 /* 966 * Flags for page_t p_toxic, for tracking memory hardware errors. 967 * 968 * These flags are OR'ed into p_toxic with page_settoxic() to track which 969 * error(s) have occurred on a given page. The flags are cleared with 970 * page_clrtoxic(). Both page_settoxic() and page_cleartoxic use atomic 971 * primitives to manipulate the p_toxic field so no other locking is needed. 972 * 973 * When an error occurs on a page, p_toxic is set to record the error. The 974 * error could be a memory error or something else (i.e. a datapath). The Page 975 * Retire mechanism does not try to determine the exact cause of the error; 976 * Page Retire rightly leaves that sort of determination to FMA's Diagnostic 977 * Engine (DE). 978 * 979 * Note that, while p_toxic bits can be set without holding any locks, they 980 * should only be cleared while holding the page exclusively locked. 981 * There is one exception to this, the PR_CAPTURE bit is protected by a mutex 982 * within the page capture logic and thus to set or clear the bit, that mutex 983 * needs to be held. The page does not need to be locked but the page_clrtoxic 984 * function must be used as we need an atomic operation. 985 * Also note that there is what amounts to a hack to prevent recursion with 986 * large pages such that if we are unlocking a page and the PR_CAPTURE bit is 987 * set, we will only try to capture the page if the current threads T_CAPTURING 988 * flag is not set. If the flag is set, the unlock will not try to capture 989 * the page even though the PR_CAPTURE bit is set. 990 * 991 * Pages with PR_UE or PR_FMA flags are retired unconditionally, while pages 992 * with PR_MCE are retired if the system has not retired too many of them. 993 * 994 * A page must be exclusively locked to be retired. Pages can be retired if 995 * they are mapped, modified, or both, as long as they are not marked PR_UE, 996 * since pages with uncorrectable errors cannot be relocated in memory. 997 * Once a page has been successfully retired it is zeroed, attached to the 998 * retired_pages vnode and, finally, PR_RETIRED is set in p_toxic. The other 999 * p_toxic bits are NOT cleared. Pages are not left locked after retiring them 1000 * to avoid special case code throughout the kernel; rather, page_*lock() will 1001 * fail to lock the page, unless SE_RETIRED is passed as an argument. 1002 * 1003 * While we have your attention, go take a look at the comments at the 1004 * beginning of page_retire.c too. 1005 */ 1006 #define PR_OK 0x00 /* no problem */ 1007 #define PR_MCE 0x01 /* page has seen two or more CEs */ 1008 #define PR_UE 0x02 /* page has an unhandled UE */ 1009 #define PR_UE_SCRUBBED 0x04 /* page has seen a UE but was cleaned */ 1010 #define PR_FMA 0x08 /* A DE wants this page retired */ 1011 #define PR_CAPTURE 0x10 /* page is hashed on page_capture_hash[] */ 1012 #define PR_RESV 0x20 /* Reserved for future use */ 1013 #define PR_MSG 0x40 /* message(s) already printed for this page */ 1014 #define PR_RETIRED 0x80 /* This page has been retired */ 1015 1016 #define PR_REASONS (PR_UE | PR_MCE | PR_FMA) 1017 #define PR_TOXIC (PR_UE) 1018 #define PR_ERRMASK (PR_UE | PR_UE_SCRUBBED | PR_MCE | PR_FMA) 1019 #define PR_TOXICFLAGS (0xCF) 1020 1021 #define PP_RETIRED(pp) ((pp)->p_toxic & PR_RETIRED) 1022 #define PP_TOXIC(pp) ((pp)->p_toxic & PR_TOXIC) 1023 #define PP_PR_REQ(pp) (((pp)->p_toxic & PR_REASONS) && !PP_RETIRED(pp)) 1024 #define PP_PR_NOSHARE(pp) \ 1025 ((((pp)->p_toxic & (PR_RETIRED | PR_FMA | PR_UE)) == PR_FMA) && \ 1026 !PP_ISKAS(pp)) 1027 1028 /* 1029 * Flags for page_unretire_pp 1030 */ 1031 #define PR_UNR_FREE 0x1 1032 #define PR_UNR_CLEAN 0x2 1033 #define PR_UNR_TEMP 0x4 1034 1035 /* 1036 * kpm large page description. 1037 * The virtual address range of segkpm is divided into chunks of 1038 * kpm_pgsz. Each chunk is controlled by a kpm_page_t. The ushort 1039 * is sufficient for 2^^15 * PAGESIZE, so e.g. the maximum kpm_pgsz 1040 * for 8K is 256M and 2G for 64K pages. It it kept as small as 1041 * possible to save physical memory space. 1042 * 1043 * There are 2 segkpm mapping windows within in the virtual address 1044 * space when we have to prevent VAC alias conflicts. The so called 1045 * Alias window (mappings are always by PAGESIZE) is controlled by 1046 * kp_refcnta. The regular window is controlled by kp_refcnt for the 1047 * normal operation, which is to use the largest available pagesize. 1048 * When VAC alias conflicts are present within a chunk in the regular 1049 * window the large page mapping is broken up into smaller PAGESIZE 1050 * mappings. kp_refcntc is used to control the pages that are invoked 1051 * in the conflict and kp_refcnts holds the active mappings done 1052 * with the small page size. In non vac conflict mode kp_refcntc is 1053 * also used as "go" indication (-1) for the trap level tsbmiss 1054 * handler. 1055 */ 1056 typedef struct kpm_page { 1057 short kp_refcnt; /* pages mapped large */ 1058 short kp_refcnta; /* pages mapped in Alias window */ 1059 short kp_refcntc; /* TL-tsbmiss flag; #vac alias conflict pages */ 1060 short kp_refcnts; /* vac alias: pages mapped small */ 1061 } kpm_page_t; 1062 1063 /* 1064 * Note: khl_lock offset changes must be reflected in sfmmu_asm.s 1065 */ 1066 typedef struct kpm_hlk { 1067 kmutex_t khl_mutex; /* kpm_page mutex */ 1068 uint_t khl_lock; /* trap level tsbmiss handling */ 1069 } kpm_hlk_t; 1070 1071 /* 1072 * kpm small page description. 1073 * When kpm_pgsz is equal to PAGESIZE a smaller representation is used 1074 * to save memory space. Alias range mappings and regular segkpm 1075 * mappings are done in units of PAGESIZE and can share the mapping 1076 * information and the mappings are always distinguishable by their 1077 * virtual address. Other information needed for VAC conflict prevention 1078 * is already available on a per page basis. 1079 * 1080 * The state about how a kpm page is mapped and whether it is ready to go 1081 * is indicated by the following 1 byte kpm_spage structure. This byte is 1082 * split into two 4-bit parts - kp_mapped and kp_mapped_go. 1083 * - kp_mapped == 1 the page is mapped cacheable 1084 * - kp_mapped == 2 the page is mapped non-cacheable 1085 * - kp_mapped_go == 1 the mapping is ready to be dropped in 1086 * - kp_mapped_go == 0 the mapping is not ready to be dropped in. 1087 * When kp_mapped_go == 0, we will have C handler resolve the VAC conflict. 1088 * Otherwise, the assembly tsb miss handler can simply drop in the mapping 1089 * when a tsb miss occurs. 1090 */ 1091 typedef union kpm_spage { 1092 struct { 1093 #ifdef _BIG_ENDIAN 1094 uchar_t mapped_go: 4; /* go or nogo flag */ 1095 uchar_t mapped: 4; /* page mapped small */ 1096 #else 1097 uchar_t mapped: 4; /* page mapped small */ 1098 uchar_t mapped_go: 4; /* go or nogo flag */ 1099 #endif 1100 } kpm_spage_un; 1101 uchar_t kp_mapped_flag; 1102 } kpm_spage_t; 1103 1104 #define kp_mapped kpm_spage_un.mapped 1105 #define kp_mapped_go kpm_spage_un.mapped_go 1106 1107 /* 1108 * Note: kshl_lock offset changes must be reflected in sfmmu_asm.s 1109 */ 1110 typedef struct kpm_shlk { 1111 uint_t kshl_lock; /* trap level tsbmiss handling */ 1112 } kpm_shlk_t; 1113 1114 /* 1115 * Each segment of physical memory is described by a memseg struct. 1116 * Within a segment, memory is considered contiguous. The members 1117 * can be categorized as follows: 1118 * . Platform independent: 1119 * pages, epages, pages_base, pages_end, next, lnext. 1120 * . 64bit only but platform independent: 1121 * kpm_pbase, kpm_nkpmpgs, kpm_pages, kpm_spages. 1122 * . Really platform or mmu specific: 1123 * pagespa, epagespa, nextpa, kpm_pagespa. 1124 * . Mixed: 1125 * msegflags. 1126 */ 1127 struct memseg { 1128 page_t *pages, *epages; /* [from, to] in page array */ 1129 pfn_t pages_base, pages_end; /* [from, to] in page numbers */ 1130 struct memseg *next; /* next segment in list */ 1131 struct memseg *lnext; /* next segment in deleted list */ 1132 #if defined(__sparc) 1133 uint64_t pagespa, epagespa; /* [from, to] page array physical */ 1134 uint64_t nextpa; /* physical next pointer */ 1135 pfn_t kpm_pbase; /* start of kpm range */ 1136 pgcnt_t kpm_nkpmpgs; /* # of kpm_pgsz pages */ 1137 union _mseg_un { 1138 kpm_page_t *kpm_lpgs; /* ptr to kpm_page array */ 1139 kpm_spage_t *kpm_spgs; /* ptr to kpm_spage array */ 1140 } mseg_un; 1141 uint64_t kpm_pagespa; /* physical ptr to kpm (s)pages array */ 1142 #endif /* __sparc */ 1143 uint_t msegflags; /* memseg flags */ 1144 }; 1145 1146 /* memseg union aliases */ 1147 #define kpm_pages mseg_un.kpm_lpgs 1148 #define kpm_spages mseg_un.kpm_spgs 1149 1150 /* msegflags */ 1151 #define MEMSEG_DYNAMIC 0x1 /* DR: memory was added dynamically */ 1152 #define MEMSEG_META_INCL 0x2 /* DR: memseg includes it's metadata */ 1153 #define MEMSEG_META_ALLOC 0x4 /* DR: memseg allocated it's metadata */ 1154 1155 /* memseg support macros */ 1156 #define MSEG_NPAGES(SEG) ((SEG)->pages_end - (SEG)->pages_base) 1157 1158 /* memseg hash */ 1159 #define MEM_HASH_SHIFT 0x9 1160 #define N_MEM_SLOTS 0x200 /* must be a power of 2 */ 1161 #define MEMSEG_PFN_HASH(pfn) (((pfn)/mhash_per_slot) & (N_MEM_SLOTS - 1)) 1162 1163 /* memseg externals */ 1164 extern struct memseg *memsegs; /* list of memory segments */ 1165 extern ulong_t mhash_per_slot; 1166 extern uint64_t memsegspa; /* memsegs as physical address */ 1167 1168 void build_pfn_hash(); 1169 extern struct memseg *page_numtomemseg_nolock(pfn_t pfnum); 1170 1171 /* 1172 * page capture related info: 1173 * The page capture routines allow us to asynchronously capture given pages 1174 * for the explicit use of the requestor. New requestors can be added by 1175 * explicitly adding themselves to the PC_* flags below and incrementing 1176 * PC_NUM_CALLBACKS as necessary. 1177 * 1178 * Subsystems using page capture must register a callback before attempting 1179 * to capture a page. A duration of -1 will indicate that we will never give 1180 * up while trying to capture a page and will only stop trying to capture the 1181 * given page once we have successfully captured it. Thus the user needs to be 1182 * aware of the behavior of all callers who have a duration of -1. 1183 * 1184 * For now, only /dev/physmem and page retire use the page capture interface 1185 * and only a single request can be outstanding for a given page. Thus, if 1186 * /dev/phsymem wants a page and page retire also wants the same page, only 1187 * the page retire request will be honored until the point in time that the 1188 * page is actually retired, at which point in time, subsequent requests by 1189 * /dev/physmem will succeed if the CAPTURE_GET_RETIRED flag was set. 1190 */ 1191 1192 #define PC_RETIRE (0) 1193 #define PC_PHYSMEM (1) 1194 #define PC_NUM_CALLBACKS (2) 1195 #define PC_MASK ((1 << PC_NUM_CALLBACKS) - 1) 1196 1197 #define CAPTURE_RETIRE (1 << PC_RETIRE) 1198 #define CAPTURE_PHYSMEM (1 << PC_PHYSMEM) 1199 1200 #define CAPTURE_ASYNC (0x0200) 1201 1202 #define CAPTURE_GET_RETIRED (0x1000) 1203 #define CAPTURE_GET_CAGE (0x2000) 1204 1205 struct page_capture_callback { 1206 int cb_active; /* 1 means active, 0 means inactive */ 1207 clock_t duration; /* the length in time that we'll attempt to */ 1208 /* capture this page asynchronously. (in HZ) */ 1209 krwlock_t cb_rwlock; 1210 int (*cb_func)(page_t *, void *, uint_t); /* callback function */ 1211 }; 1212 1213 extern kcondvar_t pc_cv; 1214 1215 void page_capture_register_callback(uint_t index, clock_t duration, 1216 int (*cb_func)(page_t *, void *, uint_t)); 1217 void page_capture_unregister_callback(uint_t index); 1218 int page_trycapture(page_t *pp, uint_t szc, uint_t flags, void *datap); 1219 void page_unlock_capture(page_t *pp); 1220 int page_capture_unretire_pp(page_t *); 1221 1222 extern int memsegs_trylock(int); 1223 extern void memsegs_lock(int); 1224 extern void memsegs_unlock(int); 1225 extern int memsegs_lock_held(void); 1226 extern void memlist_read_lock(void); 1227 extern void memlist_read_unlock(void); 1228 extern void memlist_write_lock(void); 1229 extern void memlist_write_unlock(void); 1230 1231 #ifdef __cplusplus 1232 } 1233 #endif 1234 1235 #endif /* _VM_PAGE_H */ 1236