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 2008 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_ANON_H 40 #define _VM_ANON_H 41 42 #pragma ident "%Z%%M% %I% %E% SMI" 43 44 #include <sys/cred.h> 45 #include <sys/zone.h> 46 #include <vm/seg.h> 47 #include <vm/vpage.h> 48 49 #ifdef __cplusplus 50 extern "C" { 51 #endif 52 53 /* 54 * VM - Anonymous pages. 55 */ 56 57 typedef unsigned long anoff_t; /* anon offsets */ 58 59 /* 60 * Each anonymous page, either in memory or in swap, has an anon structure. 61 * The structure (slot) provides a level of indirection between anonymous pages 62 * and their backing store. 63 * 64 * (an_vp, an_off) names the vnode of the anonymous page for this slot. 65 * 66 * (an_pvp, an_poff) names the location of the physical backing store 67 * for the page this slot represents. If the name is null there is no 68 * associated physical store. The physical backing store location can 69 * change while the slot is in use. 70 * 71 * an_hash is a hash list of anon slots. The list is hashed by 72 * (an_vp, an_off) of the associated anonymous page and provides a 73 * method of going from the name of an anonymous page to its 74 * associated anon slot. 75 * 76 * an_refcnt holds a reference count which is the number of separate 77 * copies that will need to be created in case of copy-on-write. 78 * A refcnt > 0 protects the existence of the slot. The refcnt is 79 * initialized to 1 when the anon slot is created in anon_alloc(). 80 * If a client obtains an anon slot and allows multiple threads to 81 * share it, then it is the client's responsibility to insure that 82 * it does not allow one thread to try to reference the slot at the 83 * same time as another is trying to decrement the last count and 84 * destroy the anon slot. E.g., the seg_vn segment type protects 85 * against this with higher level locks. 86 */ 87 88 struct anon { 89 struct vnode *an_vp; /* vnode of anon page */ 90 struct vnode *an_pvp; /* vnode of physical backing store */ 91 anoff_t an_off; /* offset of anon page */ 92 anoff_t an_poff; /* offset in vnode */ 93 struct anon *an_hash; /* hash table of anon slots */ 94 int an_refcnt; /* # of people sharing slot */ 95 }; 96 97 #ifdef _KERNEL 98 /* 99 * The swapinfo_lock protects: 100 * swapinfo list 101 * individual swapinfo structures 102 * 103 * The anoninfo_lock protects: 104 * anoninfo counters 105 * 106 * The anonhash_lock protects: 107 * anon hash lists 108 * anon slot fields 109 * 110 * Fields in the anon slot which are read-only for the life of the slot 111 * (an_vp, an_off) do not require the anonhash_lock be held to access them. 112 * If you access a field without the anonhash_lock held you must be holding 113 * the slot with an_refcnt to make sure it isn't destroyed. 114 * To write (an_pvp, an_poff) in a given slot you must also hold the 115 * p_iolock of the anonymous page for slot. 116 */ 117 extern kmutex_t anoninfo_lock; 118 extern kmutex_t swapinfo_lock; 119 extern kmutex_t anonhash_lock[]; 120 extern pad_mutex_t anon_array_lock[]; 121 extern kcondvar_t anon_array_cv[]; 122 123 /* 124 * Global hash table to provide a function from (vp, off) -> ap 125 */ 126 extern size_t anon_hash_size; 127 extern struct anon **anon_hash; 128 #define ANON_HASH_SIZE anon_hash_size 129 #define ANON_HASHAVELEN 4 130 #define ANON_HASH(VP, OFF) \ 131 ((((uintptr_t)(VP) >> 7) ^ ((OFF) >> PAGESHIFT)) & (ANON_HASH_SIZE - 1)) 132 133 #define AH_LOCK_SIZE 64 134 #define AH_LOCK(vp, off) (ANON_HASH((vp), (off)) & (AH_LOCK_SIZE -1)) 135 136 #endif /* _KERNEL */ 137 138 /* 139 * Declaration for the Global counters to accurately 140 * track the kernel foot print in memory. 141 */ 142 extern pgcnt_t pages_locked; 143 extern pgcnt_t pages_claimed; 144 extern pgcnt_t pages_useclaim; 145 extern pgcnt_t obp_pages; 146 147 /* 148 * Anonymous backing store accounting structure for swapctl. 149 * 150 * ani_max = maximum amount of swap space 151 * (including potentially available physical memory) 152 * ani_free = amount of unallocated anonymous memory 153 * (some of which might be reserved and including 154 * potentially available physical memory) 155 * ani_resv = amount of claimed (reserved) anonymous memory 156 * 157 * The swap data can be aquired more efficiently through the 158 * kstats interface. 159 * Total slots currently available for reservation = 160 * MAX(ani_max - ani_resv, 0) + (availrmem - swapfs_minfree) 161 */ 162 struct anoninfo { 163 pgcnt_t ani_max; 164 pgcnt_t ani_free; 165 pgcnt_t ani_resv; 166 }; 167 168 #ifdef _SYSCALL32 169 struct anoninfo32 { 170 size32_t ani_max; 171 size32_t ani_free; 172 size32_t ani_resv; 173 }; 174 #endif /* _SYSCALL32 */ 175 176 /* 177 * Define the NCPU pool of the ani_free counters. Update the counter 178 * of the cpu on which the thread is running and in every clock intr 179 * sync anoninfo.ani_free with the current total off all the NCPU entries. 180 */ 181 182 typedef struct ani_free { 183 kmutex_t ani_lock; 184 pgcnt_t ani_count; 185 uchar_t pad[64 - sizeof (kmutex_t) - sizeof (pgcnt_t)]; 186 /* XXX 64 = cacheline size */ 187 } ani_free_t; 188 189 #define ANI_MAX_POOL 128 190 extern ani_free_t ani_free_pool[]; 191 192 #define ANI_ADD(inc) { \ 193 ani_free_t *anifp; \ 194 int index; \ 195 index = (CPU->cpu_id & (ANI_MAX_POOL - 1)); \ 196 anifp = &ani_free_pool[index]; \ 197 mutex_enter(&anifp->ani_lock); \ 198 anifp->ani_count += inc; \ 199 mutex_exit(&anifp->ani_lock); \ 200 } 201 202 /* 203 * Anon array pointers are allocated in chunks. Each chunk 204 * has PAGESIZE/sizeof(u_long *) of anon pointers. 205 * There are two levels of arrays for anon array pointers larger 206 * than a chunk. The first level points to anon array chunks. 207 * The second level consists of chunks of anon pointers. 208 * 209 * If anon array is smaller than a chunk then the whole anon array 210 * is created (memory is allocated for whole anon array). 211 * If anon array is larger than a chunk only first level array is 212 * allocated. Then other arrays (chunks) are allocated only when 213 * they are initialized with anon pointers. 214 */ 215 struct anon_hdr { 216 kmutex_t serial_lock; /* serialize array chunk allocation */ 217 pgcnt_t size; /* number of pointers to (anon) pages */ 218 void **array_chunk; /* pointers to anon pointers or chunks of */ 219 /* anon pointers */ 220 int flags; /* ANON_ALLOC_FORCE force preallocation of */ 221 /* whole anon array */ 222 }; 223 224 #ifdef _LP64 225 #define ANON_PTRSHIFT 3 226 #define ANON_PTRMASK ~7 227 #else 228 #define ANON_PTRSHIFT 2 229 #define ANON_PTRMASK ~3 230 #endif 231 232 #define ANON_CHUNK_SIZE (PAGESIZE >> ANON_PTRSHIFT) 233 #define ANON_CHUNK_SHIFT (PAGESHIFT - ANON_PTRSHIFT) 234 #define ANON_CHUNK_OFF (ANON_CHUNK_SIZE - 1) 235 236 /* 237 * Anon flags. 238 */ 239 #define ANON_SLEEP 0x0 /* ok to block */ 240 #define ANON_NOSLEEP 0x1 /* non-blocking call */ 241 #define ANON_ALLOC_FORCE 0x2 /* force single level anon array */ 242 #define ANON_GROWDOWN 0x4 /* anon array should grow downward */ 243 244 struct kshmid; 245 246 /* 247 * The anon_map structure is used by various clients of the anon layer to 248 * manage anonymous memory. When anonymous memory is shared, 249 * then the different clients sharing it will point to the 250 * same anon_map structure. Also, if a segment is unmapped 251 * in the middle where an anon_map structure exists, the 252 * newly created segment will also share the anon_map structure, 253 * although the two segments will use different ranges of the 254 * anon array. When mappings are private (or shared with 255 * a reference count of 1), an unmap operation will free up 256 * a range of anon slots in the array given by the anon_map 257 * structure. Because of fragmentation due to this unmapping, 258 * we have to store the size of the anon array in the anon_map 259 * structure so that we can free everything when the referernce 260 * count goes to zero. 261 * 262 * A new rangelock scheme is introduced to make the anon layer scale. 263 * A reader/writer lock per anon_amp and an array of system-wide hash 264 * locks, anon_array_lock[] are introduced to replace serial_lock and 265 * anonmap lock. The writer lock is held when we want to singlethreaD 266 * the reference to the anon array pointers or when references to 267 * anon_map's members, whereas reader lock and anon_array_lock are 268 * held to allows multiple threads to reference different part of 269 * anon array. A global set of condition variables, anon_array_cv, 270 * are used with anon_array_lock[] to make the hold time of the locks 271 * short. 272 * 273 * szc is used to calculate the index of hash locks and cv's. We 274 * could've just used seg->s_szc if not for the possible sharing of 275 * anon_amp between SYSV shared memory and ISM, so now we introduce 276 * szc in the anon_map structure. For MAP_SHARED, the amp->szc is either 277 * 0 (base page size) or page_num_pagesizes() - 1, while MAP_PRIVATE 278 * the amp->szc could be anything in [0, page_num_pagesizes() - 1]. 279 */ 280 typedef struct anon_map { 281 krwlock_t a_rwlock; /* protect anon_map and anon array */ 282 size_t size; /* size in bytes mapped by the anon array */ 283 struct anon_hdr *ahp; /* anon array header pointer, containing */ 284 /* anon pointer array(s) */ 285 size_t swresv; /* swap space reserved for this anon_map */ 286 ulong_t refcnt; /* reference count on this structure */ 287 ushort_t a_szc; /* max szc among shared processes */ 288 void *locality; /* lgroup locality info */ 289 struct kshmid *a_sp; /* kshmid if amp backs sysV, or NULL */ 290 int a_purgewait; /* somebody waits for slocks to go away */ 291 kcondvar_t a_purgecv; /* cv for waiting for slocks to go away */ 292 kmutex_t a_purgemtx; /* mutex for anonmap_purge() */ 293 spgcnt_t a_softlockcnt; /* number of pages locked in pcache */ 294 kmutex_t a_pmtx; /* protects amp's pcache list */ 295 pcache_link_t a_phead; /* head of amp's pcache list */ 296 } amp_t; 297 298 #ifdef _KERNEL 299 300 #define ANON_BUSY 0x1 301 #define ANON_ISBUSY(slot) (*(slot) & ANON_BUSY) 302 #define ANON_SETBUSY(slot) (*(slot) |= ANON_BUSY) 303 #define ANON_CLRBUSY(slot) (*(slot) &= ~ANON_BUSY) 304 305 #define ANON_MAP_SHIFT 6 /* log2(sizeof (struct anon_map)) */ 306 #define ANON_ARRAY_SHIFT 7 /* log2(ANON_LOCKSIZE) */ 307 #define ANON_LOCKSIZE 128 308 309 #define ANON_LOCK_ENTER(lock, type) rw_enter((lock), (type)) 310 #define ANON_LOCK_EXIT(lock) rw_exit((lock)) 311 #define ANON_LOCK_HELD(lock) RW_LOCK_HELD((lock)) 312 #define ANON_READ_HELD(lock) RW_READ_HELD((lock)) 313 #define ANON_WRITE_HELD(lock) RW_WRITE_HELD((lock)) 314 315 #define ANON_ARRAY_HASH(amp, idx)\ 316 ((((idx) + ((idx) >> ANON_ARRAY_SHIFT) +\ 317 ((idx) >> (ANON_ARRAY_SHIFT << 1)) +\ 318 ((idx) >> (ANON_ARRAY_SHIFT + (ANON_ARRAY_SHIFT << 1)))) ^\ 319 ((uintptr_t)(amp) >> ANON_MAP_SHIFT)) & (ANON_LOCKSIZE - 1)) 320 321 typedef struct anon_sync_obj { 322 kmutex_t *sync_mutex; 323 kcondvar_t *sync_cv; 324 ulong_t *sync_data; 325 } anon_sync_obj_t; 326 327 /* 328 * Anonymous backing store accounting structure for kernel. 329 * ani_max = total reservable slots on physical (disk-backed) swap 330 * ani_phys_resv = total phys slots reserved for use by clients 331 * ani_mem_resv = total mem slots reserved for use by clients 332 * ani_free = # unallocated physical slots + # of reserved unallocated 333 * memory slots 334 */ 335 336 /* 337 * Initial total swap slots available for reservation 338 */ 339 #define TOTAL_AVAILABLE_SWAP \ 340 (k_anoninfo.ani_max + MAX((spgcnt_t)(availrmem - swapfs_minfree), 0)) 341 342 /* 343 * Swap slots currently available for reservation 344 */ 345 #define CURRENT_TOTAL_AVAILABLE_SWAP \ 346 ((k_anoninfo.ani_max - k_anoninfo.ani_phys_resv) + \ 347 MAX((spgcnt_t)(availrmem - swapfs_minfree), 0)) 348 349 struct k_anoninfo { 350 pgcnt_t ani_max; /* total reservable slots on phys */ 351 /* (disk) swap */ 352 pgcnt_t ani_free; /* # of unallocated phys and mem slots */ 353 pgcnt_t ani_phys_resv; /* # of reserved phys (disk) slots */ 354 pgcnt_t ani_mem_resv; /* # of reserved mem slots */ 355 pgcnt_t ani_locked_swap; /* # of swap slots locked in reserved */ 356 /* mem swap */ 357 }; 358 359 extern struct k_anoninfo k_anoninfo; 360 361 extern void anon_init(void); 362 extern struct anon *anon_alloc(struct vnode *, anoff_t); 363 extern void anon_dup(struct anon_hdr *, ulong_t, 364 struct anon_hdr *, ulong_t, size_t); 365 extern void anon_dup_fill_holes(struct anon_hdr *, ulong_t, 366 struct anon_hdr *, ulong_t, size_t, uint_t, int); 367 extern int anon_fill_cow_holes(struct seg *, caddr_t, struct anon_hdr *, 368 ulong_t, struct vnode *, u_offset_t, size_t, uint_t, 369 uint_t, struct vpage [], struct cred *); 370 extern void anon_free(struct anon_hdr *, ulong_t, size_t); 371 extern void anon_free_pages(struct anon_hdr *, ulong_t, size_t, uint_t); 372 extern void anon_disclaim(struct anon_map *, ulong_t, size_t); 373 extern int anon_getpage(struct anon **, uint_t *, struct page **, 374 size_t, struct seg *, caddr_t, enum seg_rw, struct cred *); 375 extern int swap_getconpage(struct vnode *, u_offset_t, size_t, 376 uint_t *, page_t *[], size_t, page_t *, uint_t *, 377 spgcnt_t *, struct seg *, caddr_t, 378 enum seg_rw, struct cred *); 379 extern int anon_map_getpages(struct anon_map *, ulong_t, 380 uint_t, struct seg *, caddr_t, uint_t, 381 uint_t *, page_t *[], uint_t *, 382 struct vpage [], enum seg_rw, int, int, int, struct cred *); 383 extern int anon_map_privatepages(struct anon_map *, ulong_t, 384 uint_t, struct seg *, caddr_t, uint_t, 385 page_t *[], struct vpage [], int, int, struct cred *); 386 extern struct page *anon_private(struct anon **, struct seg *, 387 caddr_t, uint_t, struct page *, 388 int, struct cred *); 389 extern struct page *anon_zero(struct seg *, caddr_t, 390 struct anon **, struct cred *); 391 extern int anon_map_createpages(struct anon_map *, ulong_t, 392 size_t, struct page **, 393 struct seg *, caddr_t, 394 enum seg_rw, struct cred *); 395 extern int anon_map_demotepages(struct anon_map *, ulong_t, 396 struct seg *, caddr_t, uint_t, 397 struct vpage [], struct cred *); 398 extern void anon_shmap_free_pages(struct anon_map *, ulong_t, size_t); 399 extern int anon_resvmem(size_t, boolean_t, zone_t *, int); 400 extern void anon_unresvmem(size_t, zone_t *); 401 extern struct anon_map *anonmap_alloc(size_t, size_t, int); 402 extern void anonmap_free(struct anon_map *); 403 extern void anonmap_purge(struct anon_map *); 404 extern void anon_swap_free(struct anon *, struct page *); 405 extern void anon_decref(struct anon *); 406 extern int non_anon(struct anon_hdr *, ulong_t, u_offset_t *, size_t *); 407 extern pgcnt_t anon_pages(struct anon_hdr *, ulong_t, pgcnt_t); 408 extern int anon_swap_adjust(pgcnt_t); 409 extern void anon_swap_restore(pgcnt_t); 410 extern struct anon_hdr *anon_create(pgcnt_t, int); 411 extern void anon_release(struct anon_hdr *, pgcnt_t); 412 extern struct anon *anon_get_ptr(struct anon_hdr *, ulong_t); 413 extern ulong_t *anon_get_slot(struct anon_hdr *, ulong_t); 414 extern struct anon *anon_get_next_ptr(struct anon_hdr *, ulong_t *); 415 extern int anon_set_ptr(struct anon_hdr *, ulong_t, struct anon *, int); 416 extern int anon_copy_ptr(struct anon_hdr *, ulong_t, 417 struct anon_hdr *, ulong_t, pgcnt_t, int); 418 extern pgcnt_t anon_grow(struct anon_hdr *, ulong_t *, pgcnt_t, pgcnt_t, int); 419 extern void anon_array_enter(struct anon_map *, ulong_t, 420 anon_sync_obj_t *); 421 extern int anon_array_try_enter(struct anon_map *, ulong_t, 422 anon_sync_obj_t *); 423 extern void anon_array_exit(anon_sync_obj_t *); 424 425 /* 426 * anon_resv checks to see if there is enough swap space to fulfill a 427 * request and if so, reserves the appropriate anonymous memory resources. 428 * anon_checkspace just checks to see if there is space to fulfill the request, 429 * without taking any resources. Both return 1 if successful and 0 if not. 430 * 431 * Macros are provided as anon reservation is usually charged to the zone of 432 * the current process. In some cases (such as anon reserved by tmpfs), a 433 * zone pointer is needed to charge the appropriate zone. 434 */ 435 #define anon_unresv(size) anon_unresvmem(size, curproc->p_zone) 436 #define anon_unresv_zone(size, zone) anon_unresvmem(size, zone) 437 #define anon_resv(size) \ 438 anon_resvmem((size), 1, curproc->p_zone, 1) 439 #define anon_resv_zone(size, zone) anon_resvmem((size), 1, zone, 1) 440 #define anon_checkspace(size, zone) anon_resvmem((size), 0, zone, 0) 441 #define anon_try_resv_zone(size, zone) anon_resvmem((size), 1, zone, 0) 442 443 /* 444 * Flags to anon_private 445 */ 446 #define STEAL_PAGE 0x1 /* page can be stolen */ 447 #define LOCK_PAGE 0x2 /* page must be ``logically'' locked */ 448 449 /* 450 * SEGKP ANON pages that are locked are assumed to be LWP stack pages 451 * and thus count towards the user pages locked count. 452 * This value is protected by the same lock as availrmem. 453 */ 454 extern pgcnt_t anon_segkp_pages_locked; 455 456 extern int anon_debug; 457 458 #ifdef ANON_DEBUG 459 460 #define A_ANON 0x01 461 #define A_RESV 0x02 462 #define A_MRESV 0x04 463 464 /* vararg-like debugging macro. */ 465 #define ANON_PRINT(f, printf_args) \ 466 if (anon_debug & f) \ 467 printf printf_args 468 469 #else /* ANON_DEBUG */ 470 471 #define ANON_PRINT(f, printf_args) 472 473 #endif /* ANON_DEBUG */ 474 475 #endif /* _KERNEL */ 476 477 #ifdef __cplusplus 478 } 479 #endif 480 481 #endif /* _VM_ANON_H */ 482