1 /* $OpenBSD: uvm_pager.c,v 1.72 2019/12/08 12:37:45 mpi Exp $ */ 2 /* $NetBSD: uvm_pager.c,v 1.36 2000/11/27 18:26:41 chs Exp $ */ 3 4 /* 5 * Copyright (c) 1997 Charles D. Cranor and Washington University. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * from: Id: uvm_pager.c,v 1.1.2.23 1998/02/02 20:38:06 chuck Exp 29 */ 30 31 /* 32 * uvm_pager.c: generic functions used to assist the pagers. 33 */ 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/malloc.h> 38 #include <sys/pool.h> 39 #include <sys/buf.h> 40 #include <sys/atomic.h> 41 42 #include <uvm/uvm.h> 43 44 struct pool *uvm_aiobuf_pool; 45 46 struct uvm_pagerops *uvmpagerops[] = { 47 &aobj_pager, 48 &uvm_deviceops, 49 &uvm_vnodeops, 50 }; 51 52 /* 53 * the pager map: provides KVA for I/O 54 * 55 * Each uvm_pseg has room for MAX_PAGERMAP_SEGS pager io space of 56 * MAXBSIZE bytes. 57 * 58 * The number of uvm_pseg instances is dynamic using an array segs. 59 * At most UVM_PSEG_COUNT instances can exist. 60 * 61 * psegs[0] always exists (so that the pager can always map in pages). 62 * psegs[0] element 0 is always reserved for the pagedaemon. 63 * 64 * Any other pseg is automatically created when no space is available 65 * and automatically destroyed when it is no longer in use. 66 */ 67 #define MAX_PAGER_SEGS 16 68 #define PSEG_NUMSEGS (PAGER_MAP_SIZE / MAX_PAGER_SEGS / MAXBSIZE) 69 struct uvm_pseg { 70 /* Start of virtual space; 0 if not inited. */ 71 vaddr_t start; 72 /* Bitmap of the segments in use in this pseg. */ 73 int use; 74 }; 75 struct mutex uvm_pseg_lck; 76 struct uvm_pseg psegs[PSEG_NUMSEGS]; 77 78 #define UVM_PSEG_FULL(pseg) ((pseg)->use == (1 << MAX_PAGER_SEGS) - 1) 79 #define UVM_PSEG_EMPTY(pseg) ((pseg)->use == 0) 80 #define UVM_PSEG_INUSE(pseg,id) (((pseg)->use & (1 << (id))) != 0) 81 82 void uvm_pseg_init(struct uvm_pseg *); 83 vaddr_t uvm_pseg_get(int); 84 void uvm_pseg_release(vaddr_t); 85 86 /* 87 * uvm_pager_init: init pagers (at boot time) 88 */ 89 void 90 uvm_pager_init(void) 91 { 92 int lcv; 93 94 /* init pager map */ 95 uvm_pseg_init(&psegs[0]); 96 mtx_init(&uvm_pseg_lck, IPL_VM); 97 98 /* init ASYNC I/O queue */ 99 TAILQ_INIT(&uvm.aio_done); 100 101 /* call pager init functions */ 102 for (lcv = 0 ; lcv < sizeof(uvmpagerops)/sizeof(struct uvm_pagerops *); 103 lcv++) { 104 if (uvmpagerops[lcv]->pgo_init) 105 uvmpagerops[lcv]->pgo_init(); 106 } 107 } 108 109 /* 110 * Initialize a uvm_pseg. 111 * 112 * May fail, in which case seg->start == 0. 113 * 114 * Caller locks uvm_pseg_lck. 115 */ 116 void 117 uvm_pseg_init(struct uvm_pseg *pseg) 118 { 119 KASSERT(pseg->start == 0); 120 KASSERT(pseg->use == 0); 121 pseg->start = uvm_km_valloc_try(kernel_map, MAX_PAGER_SEGS * MAXBSIZE); 122 } 123 124 /* 125 * Acquire a pager map segment. 126 * 127 * Returns a vaddr for paging. 0 on failure. 128 * 129 * Caller does not lock. 130 */ 131 vaddr_t 132 uvm_pseg_get(int flags) 133 { 134 int i; 135 struct uvm_pseg *pseg; 136 137 mtx_enter(&uvm_pseg_lck); 138 139 pager_seg_restart: 140 /* Find first pseg that has room. */ 141 for (pseg = &psegs[0]; pseg != &psegs[PSEG_NUMSEGS]; pseg++) { 142 if (UVM_PSEG_FULL(pseg)) 143 continue; 144 145 if (pseg->start == 0) { 146 /* Need initialization. */ 147 uvm_pseg_init(pseg); 148 if (pseg->start == 0) 149 goto pager_seg_fail; 150 } 151 152 /* Keep index 0 reserved for pagedaemon. */ 153 if (pseg == &psegs[0] && curproc != uvm.pagedaemon_proc) 154 i = 1; 155 else 156 i = 0; 157 158 for (; i < MAX_PAGER_SEGS; i++) { 159 if (!UVM_PSEG_INUSE(pseg, i)) { 160 pseg->use |= 1 << i; 161 mtx_leave(&uvm_pseg_lck); 162 return pseg->start + i * MAXBSIZE; 163 } 164 } 165 } 166 167 pager_seg_fail: 168 if ((flags & UVMPAGER_MAPIN_WAITOK) != 0) { 169 msleep_nsec(&psegs, &uvm_pseg_lck, PVM, "pagerseg", INFSLP); 170 goto pager_seg_restart; 171 } 172 173 mtx_leave(&uvm_pseg_lck); 174 return 0; 175 } 176 177 /* 178 * Release a pager map segment. 179 * 180 * Caller does not lock. 181 * 182 * Deallocates pseg if it is no longer in use. 183 */ 184 void 185 uvm_pseg_release(vaddr_t segaddr) 186 { 187 int id; 188 struct uvm_pseg *pseg; 189 vaddr_t va = 0; 190 191 for (pseg = &psegs[0]; pseg != &psegs[PSEG_NUMSEGS]; pseg++) { 192 if (pseg->start <= segaddr && 193 segaddr < pseg->start + MAX_PAGER_SEGS * MAXBSIZE) 194 break; 195 } 196 KASSERT(pseg != &psegs[PSEG_NUMSEGS]); 197 198 id = (segaddr - pseg->start) / MAXBSIZE; 199 KASSERT(id >= 0 && id < MAX_PAGER_SEGS); 200 201 /* test for no remainder */ 202 KDASSERT(segaddr == pseg->start + id * MAXBSIZE); 203 204 mtx_enter(&uvm_pseg_lck); 205 206 KASSERT(UVM_PSEG_INUSE(pseg, id)); 207 208 pseg->use &= ~(1 << id); 209 wakeup(&psegs); 210 211 if (pseg != &psegs[0] && UVM_PSEG_EMPTY(pseg)) { 212 va = pseg->start; 213 pseg->start = 0; 214 } 215 216 mtx_leave(&uvm_pseg_lck); 217 218 if (va) 219 uvm_km_free(kernel_map, va, MAX_PAGER_SEGS * MAXBSIZE); 220 } 221 222 /* 223 * uvm_pagermapin: map pages into KVA for I/O that needs mappings 224 * 225 * We basically just km_valloc a blank map entry to reserve the space in the 226 * kernel map and then use pmap_enter() to put the mappings in by hand. 227 */ 228 vaddr_t 229 uvm_pagermapin(struct vm_page **pps, int npages, int flags) 230 { 231 vaddr_t kva, cva; 232 vm_prot_t prot; 233 vsize_t size; 234 struct vm_page *pp; 235 236 prot = PROT_READ; 237 if (flags & UVMPAGER_MAPIN_READ) 238 prot |= PROT_WRITE; 239 size = ptoa(npages); 240 241 KASSERT(size <= MAXBSIZE); 242 243 kva = uvm_pseg_get(flags); 244 if (kva == 0) 245 return 0; 246 247 for (cva = kva ; size != 0 ; size -= PAGE_SIZE, cva += PAGE_SIZE) { 248 pp = *pps++; 249 KASSERT(pp); 250 KASSERT(pp->pg_flags & PG_BUSY); 251 /* Allow pmap_enter to fail. */ 252 if (pmap_enter(pmap_kernel(), cva, VM_PAGE_TO_PHYS(pp), 253 prot, PMAP_WIRED | PMAP_CANFAIL | prot) != 0) { 254 pmap_remove(pmap_kernel(), kva, cva); 255 pmap_update(pmap_kernel()); 256 uvm_pseg_release(kva); 257 return 0; 258 } 259 } 260 pmap_update(pmap_kernel()); 261 return kva; 262 } 263 264 /* 265 * uvm_pagermapout: remove KVA mapping 266 * 267 * We remove our mappings by hand and then remove the mapping. 268 */ 269 void 270 uvm_pagermapout(vaddr_t kva, int npages) 271 { 272 273 pmap_remove(pmap_kernel(), kva, kva + ((vsize_t)npages << PAGE_SHIFT)); 274 pmap_update(pmap_kernel()); 275 uvm_pseg_release(kva); 276 277 } 278 279 /* 280 * uvm_mk_pcluster 281 * 282 * generic "make 'pager put' cluster" function. a pager can either 283 * [1] set pgo_mk_pcluster to NULL (never cluster), [2] set it to this 284 * generic function, or [3] set it to a pager specific function. 285 * 286 * => caller must lock object _and_ pagequeues (since we need to look 287 * at active vs. inactive bits, etc.) 288 * => caller must make center page busy and write-protect it 289 * => we mark all cluster pages busy for the caller 290 * => the caller must unbusy all pages (and check wanted/released 291 * status if it drops the object lock) 292 * => flags: 293 * PGO_ALLPAGES: all pages in object are valid targets 294 * !PGO_ALLPAGES: use "lo" and "hi" to limit range of cluster 295 * PGO_DOACTCLUST: include active pages in cluster. 296 * PGO_FREE: set the PG_RELEASED bits on the cluster so they'll be freed 297 * in async io (caller must clean on error). 298 * NOTE: the caller should clear PG_CLEANCHK bits if PGO_DOACTCLUST. 299 * PG_CLEANCHK is only a hint, but clearing will help reduce 300 * the number of calls we make to the pmap layer. 301 */ 302 303 struct vm_page ** 304 uvm_mk_pcluster(struct uvm_object *uobj, struct vm_page **pps, int *npages, 305 struct vm_page *center, int flags, voff_t mlo, voff_t mhi) 306 { 307 struct vm_page **ppsp, *pclust; 308 voff_t lo, hi, curoff; 309 int center_idx, forward, incr; 310 311 /* 312 * center page should already be busy and write protected. XXX: 313 * suppose page is wired? if we lock, then a process could 314 * fault/block on it. if we don't lock, a process could write the 315 * pages in the middle of an I/O. (consider an msync()). let's 316 * lock it for now (better to delay than corrupt data?). 317 */ 318 /* get cluster boundaries, check sanity, and apply our limits as well.*/ 319 uobj->pgops->pgo_cluster(uobj, center->offset, &lo, &hi); 320 if ((flags & PGO_ALLPAGES) == 0) { 321 if (lo < mlo) 322 lo = mlo; 323 if (hi > mhi) 324 hi = mhi; 325 } 326 if ((hi - lo) >> PAGE_SHIFT > *npages) { /* pps too small, bail out! */ 327 pps[0] = center; 328 *npages = 1; 329 return(pps); 330 } 331 332 /* now determine the center and attempt to cluster around the edges */ 333 center_idx = (center->offset - lo) >> PAGE_SHIFT; 334 pps[center_idx] = center; /* plug in the center page */ 335 ppsp = &pps[center_idx]; 336 *npages = 1; 337 338 /* 339 * attempt to cluster around the left [backward], and then 340 * the right side [forward]. 341 * 342 * note that for inactive pages (pages that have been deactivated) 343 * there are no valid mappings and PG_CLEAN should be up to date. 344 * [i.e. there is no need to query the pmap with pmap_is_modified 345 * since there are no mappings]. 346 */ 347 for (forward = 0 ; forward <= 1 ; forward++) { 348 incr = forward ? PAGE_SIZE : -PAGE_SIZE; 349 curoff = center->offset + incr; 350 for ( ;(forward == 0 && curoff >= lo) || 351 (forward && curoff < hi); 352 curoff += incr) { 353 354 pclust = uvm_pagelookup(uobj, curoff); /* lookup page */ 355 if (pclust == NULL) { 356 break; /* no page */ 357 } 358 /* handle active pages */ 359 /* NOTE: inactive pages don't have pmap mappings */ 360 if ((pclust->pg_flags & PQ_INACTIVE) == 0) { 361 if ((flags & PGO_DOACTCLUST) == 0) { 362 /* dont want mapped pages at all */ 363 break; 364 } 365 366 /* make sure "clean" bit is sync'd */ 367 if ((pclust->pg_flags & PG_CLEANCHK) == 0) { 368 if ((pclust->pg_flags & (PG_CLEAN|PG_BUSY)) 369 == PG_CLEAN && 370 pmap_is_modified(pclust)) 371 atomic_clearbits_int( 372 &pclust->pg_flags, 373 PG_CLEAN); 374 /* now checked */ 375 atomic_setbits_int(&pclust->pg_flags, 376 PG_CLEANCHK); 377 } 378 } 379 380 /* is page available for cleaning and does it need it */ 381 if ((pclust->pg_flags & (PG_CLEAN|PG_BUSY)) != 0) { 382 break; /* page is already clean or is busy */ 383 } 384 385 /* yes! enroll the page in our array */ 386 atomic_setbits_int(&pclust->pg_flags, PG_BUSY); 387 UVM_PAGE_OWN(pclust, "uvm_mk_pcluster"); 388 389 /* 390 * If we want to free after io is done, and we're 391 * async, set the released flag 392 */ 393 if ((flags & (PGO_FREE|PGO_SYNCIO)) == PGO_FREE) 394 atomic_setbits_int(&pclust->pg_flags, 395 PG_RELEASED); 396 397 /* XXX: protect wired page? see above comment. */ 398 pmap_page_protect(pclust, PROT_READ); 399 if (!forward) { 400 ppsp--; /* back up one page */ 401 *ppsp = pclust; 402 } else { 403 /* move forward one page */ 404 ppsp[*npages] = pclust; 405 } 406 (*npages)++; 407 } 408 } 409 410 /* 411 * done! return the cluster array to the caller!!! 412 */ 413 return(ppsp); 414 } 415 416 /* 417 * uvm_pager_put: high level pageout routine 418 * 419 * we want to pageout page "pg" to backing store, clustering if 420 * possible. 421 * 422 * => page queues must be locked by caller 423 * => if page is not swap-backed, then "uobj" points to the object 424 * backing it. 425 * => if page is swap-backed, then "uobj" should be NULL. 426 * => "pg" should be PG_BUSY (by caller), and !PG_CLEAN 427 * for swap-backed memory, "pg" can be NULL if there is no page 428 * of interest [sometimes the case for the pagedaemon] 429 * => "ppsp_ptr" should point to an array of npages vm_page pointers 430 * for possible cluster building 431 * => flags (first two for non-swap-backed pages) 432 * PGO_ALLPAGES: all pages in uobj are valid targets 433 * PGO_DOACTCLUST: include "PQ_ACTIVE" pages as valid targets 434 * PGO_SYNCIO: do SYNC I/O (no async) 435 * PGO_PDFREECLUST: pagedaemon: drop cluster on successful I/O 436 * PGO_FREE: tell the aio daemon to free pages in the async case. 437 * => start/stop: if (uobj && !PGO_ALLPAGES) limit targets to this range 438 * if (!uobj) start is the (daddr_t) of the starting swapblk 439 * => return state: 440 * 1. we return the VM_PAGER status code of the pageout 441 * 2. we return with the page queues unlocked 442 * 3. on errors we always drop the cluster. thus, if we return 443 * !PEND, !OK, then the caller only has to worry about 444 * un-busying the main page (not the cluster pages). 445 * 4. on success, if !PGO_PDFREECLUST, we return the cluster 446 * with all pages busy (caller must un-busy and check 447 * wanted/released flags). 448 */ 449 int 450 uvm_pager_put(struct uvm_object *uobj, struct vm_page *pg, 451 struct vm_page ***ppsp_ptr, int *npages, int flags, 452 voff_t start, voff_t stop) 453 { 454 int result; 455 daddr_t swblk; 456 struct vm_page **ppsp = *ppsp_ptr; 457 458 /* 459 * note that uobj is null if we are doing a swap-backed pageout. 460 * note that uobj is !null if we are doing normal object pageout. 461 * note that the page queues must be locked to cluster. 462 */ 463 if (uobj) { /* if !swap-backed */ 464 /* 465 * attempt to build a cluster for pageout using its 466 * make-put-cluster function (if it has one). 467 */ 468 if (uobj->pgops->pgo_mk_pcluster) { 469 ppsp = uobj->pgops->pgo_mk_pcluster(uobj, ppsp, 470 npages, pg, flags, start, stop); 471 *ppsp_ptr = ppsp; /* update caller's pointer */ 472 } else { 473 ppsp[0] = pg; 474 *npages = 1; 475 } 476 477 swblk = 0; /* XXX: keep gcc happy */ 478 } else { 479 /* 480 * for swap-backed pageout, the caller (the pagedaemon) has 481 * already built the cluster for us. the starting swap 482 * block we are writing to has been passed in as "start." 483 * "pg" could be NULL if there is no page we are especially 484 * interested in (in which case the whole cluster gets dropped 485 * in the event of an error or a sync "done"). 486 */ 487 swblk = start; 488 /* ppsp and npages should be ok */ 489 } 490 491 /* now that we've clustered we can unlock the page queues */ 492 uvm_unlock_pageq(); 493 494 /* 495 * now attempt the I/O. if we have a failure and we are 496 * clustered, we will drop the cluster and try again. 497 */ 498 ReTry: 499 if (uobj) { 500 result = uobj->pgops->pgo_put(uobj, ppsp, *npages, flags); 501 } else { 502 /* XXX daddr_t -> int */ 503 result = uvm_swap_put(swblk, ppsp, *npages, flags); 504 } 505 506 /* 507 * we have attempted the I/O. 508 * 509 * if the I/O was a success then: 510 * if !PGO_PDFREECLUST, we return the cluster to the 511 * caller (who must un-busy all pages) 512 * else we un-busy cluster pages for the pagedaemon 513 * 514 * if I/O is pending (async i/o) then we return the pending code. 515 * [in this case the async i/o done function must clean up when 516 * i/o is done...] 517 */ 518 if (result == VM_PAGER_PEND || result == VM_PAGER_OK) { 519 if (result == VM_PAGER_OK && (flags & PGO_PDFREECLUST)) { 520 /* drop cluster */ 521 if (*npages > 1 || pg == NULL) 522 uvm_pager_dropcluster(uobj, pg, ppsp, npages, 523 PGO_PDFREECLUST); 524 } 525 return (result); 526 } 527 528 /* 529 * a pager error occured (even after dropping the cluster, if there 530 * was one). give up! the caller only has one page ("pg") 531 * to worry about. 532 */ 533 if (*npages > 1 || pg == NULL) { 534 uvm_pager_dropcluster(uobj, pg, ppsp, npages, PGO_REALLOCSWAP); 535 536 /* 537 * for failed swap-backed pageouts with a "pg", 538 * we need to reset pg's swslot to either: 539 * "swblk" (for transient errors, so we can retry), 540 * or 0 (for hard errors). 541 */ 542 if (uobj == NULL && pg != NULL) { 543 /* XXX daddr_t -> int */ 544 int nswblk = (result == VM_PAGER_AGAIN) ? swblk : 0; 545 if (pg->pg_flags & PQ_ANON) { 546 pg->uanon->an_swslot = nswblk; 547 } else { 548 uao_set_swslot(pg->uobject, 549 pg->offset >> PAGE_SHIFT, 550 nswblk); 551 } 552 } 553 if (result == VM_PAGER_AGAIN) { 554 /* 555 * for transient failures, free all the swslots that 556 * we're not going to retry with. 557 */ 558 if (uobj == NULL) { 559 if (pg) { 560 /* XXX daddr_t -> int */ 561 uvm_swap_free(swblk + 1, *npages - 1); 562 } else { 563 /* XXX daddr_t -> int */ 564 uvm_swap_free(swblk, *npages); 565 } 566 } 567 if (pg) { 568 ppsp[0] = pg; 569 *npages = 1; 570 goto ReTry; 571 } 572 } else if (uobj == NULL) { 573 /* 574 * for hard errors on swap-backed pageouts, 575 * mark the swslots as bad. note that we do not 576 * free swslots that we mark bad. 577 */ 578 /* XXX daddr_t -> int */ 579 uvm_swap_markbad(swblk, *npages); 580 } 581 } 582 583 /* 584 * a pager error occurred (even after dropping the cluster, if there 585 * was one). give up! the caller only has one page ("pg") 586 * to worry about. 587 */ 588 589 return(result); 590 } 591 592 /* 593 * uvm_pager_dropcluster: drop a cluster we have built (because we 594 * got an error, or, if PGO_PDFREECLUST we are un-busying the 595 * cluster pages on behalf of the pagedaemon). 596 * 597 * => uobj, if non-null, is a non-swap-backed object 598 * => page queues are not locked 599 * => pg is our page of interest (the one we clustered around, can be null) 600 * => ppsp/npages is our current cluster 601 * => flags: PGO_PDFREECLUST: pageout was a success: un-busy cluster 602 * pages on behalf of the pagedaemon. 603 * PGO_REALLOCSWAP: drop previously allocated swap slots for 604 * clustered swap-backed pages (except for "pg" if !NULL) 605 * "swblk" is the start of swap alloc (e.g. for ppsp[0]) 606 * [only meaningful if swap-backed (uobj == NULL)] 607 */ 608 609 void 610 uvm_pager_dropcluster(struct uvm_object *uobj, struct vm_page *pg, 611 struct vm_page **ppsp, int *npages, int flags) 612 { 613 int lcv; 614 615 /* drop all pages but "pg" */ 616 for (lcv = 0 ; lcv < *npages ; lcv++) { 617 /* skip "pg" or empty slot */ 618 if (ppsp[lcv] == pg || ppsp[lcv] == NULL) 619 continue; 620 621 /* 622 * Note that PQ_ANON bit can't change as long as we are holding 623 * the PG_BUSY bit (so there is no need to lock the page 624 * queues to test it). 625 */ 626 if (!uobj) { 627 if (ppsp[lcv]->pg_flags & PQ_ANON) { 628 if (flags & PGO_REALLOCSWAP) 629 /* zap swap block */ 630 ppsp[lcv]->uanon->an_swslot = 0; 631 } else { 632 if (flags & PGO_REALLOCSWAP) 633 uao_set_swslot(ppsp[lcv]->uobject, 634 ppsp[lcv]->offset >> PAGE_SHIFT, 0); 635 } 636 } 637 638 /* did someone want the page while we had it busy-locked? */ 639 if (ppsp[lcv]->pg_flags & PG_WANTED) { 640 wakeup(ppsp[lcv]); 641 } 642 643 /* if page was released, release it. otherwise un-busy it */ 644 if (ppsp[lcv]->pg_flags & PG_RELEASED && 645 ppsp[lcv]->pg_flags & PQ_ANON) { 646 /* so that anfree will free */ 647 atomic_clearbits_int(&ppsp[lcv]->pg_flags, 648 PG_BUSY); 649 UVM_PAGE_OWN(ppsp[lcv], NULL); 650 651 /* kills anon and frees pg */ 652 uvm_anfree(ppsp[lcv]->uanon); 653 654 continue; 655 } else { 656 /* 657 * if we were planning on async io then we would 658 * have PG_RELEASED set, clear that with the others. 659 */ 660 atomic_clearbits_int(&ppsp[lcv]->pg_flags, 661 PG_BUSY|PG_WANTED|PG_FAKE|PG_RELEASED); 662 UVM_PAGE_OWN(ppsp[lcv], NULL); 663 } 664 665 /* 666 * if we are operating on behalf of the pagedaemon and we 667 * had a successful pageout update the page! 668 */ 669 if (flags & PGO_PDFREECLUST) { 670 pmap_clear_reference(ppsp[lcv]); 671 pmap_clear_modify(ppsp[lcv]); 672 atomic_setbits_int(&ppsp[lcv]->pg_flags, PG_CLEAN); 673 } 674 } 675 } 676 677 /* 678 * interrupt-context iodone handler for single-buf i/os 679 * or the top-level buf of a nested-buf i/o. 680 * 681 * => must be at splbio(). 682 */ 683 684 void 685 uvm_aio_biodone(struct buf *bp) 686 { 687 splassert(IPL_BIO); 688 689 /* reset b_iodone for when this is a single-buf i/o. */ 690 bp->b_iodone = uvm_aio_aiodone; 691 692 mtx_enter(&uvm.aiodoned_lock); 693 TAILQ_INSERT_TAIL(&uvm.aio_done, bp, b_freelist); 694 wakeup(&uvm.aiodoned); 695 mtx_leave(&uvm.aiodoned_lock); 696 } 697 698 /* 699 * uvm_aio_aiodone: do iodone processing for async i/os. 700 * this should be called in thread context, not interrupt context. 701 */ 702 void 703 uvm_aio_aiodone(struct buf *bp) 704 { 705 int npages = bp->b_bufsize >> PAGE_SHIFT; 706 struct vm_page *pg, *pgs[MAXPHYS >> PAGE_SHIFT]; 707 struct uvm_object *uobj; 708 int i, error; 709 boolean_t write, swap; 710 711 KASSERT(npages <= MAXPHYS >> PAGE_SHIFT); 712 splassert(IPL_BIO); 713 714 error = (bp->b_flags & B_ERROR) ? (bp->b_error ? bp->b_error : EIO) : 0; 715 write = (bp->b_flags & B_READ) == 0; 716 717 uobj = NULL; 718 for (i = 0; i < npages; i++) 719 pgs[i] = uvm_atopg((vaddr_t)bp->b_data + 720 ((vsize_t)i << PAGE_SHIFT)); 721 uvm_pagermapout((vaddr_t)bp->b_data, npages); 722 #ifdef UVM_SWAP_ENCRYPT 723 /* 724 * XXX - assumes that we only get ASYNC writes. used to be above. 725 */ 726 if (pgs[0]->pg_flags & PQ_ENCRYPT) { 727 uvm_swap_freepages(pgs, npages); 728 goto freed; 729 } 730 #endif /* UVM_SWAP_ENCRYPT */ 731 for (i = 0; i < npages; i++) { 732 pg = pgs[i]; 733 734 if (i == 0) { 735 swap = (pg->pg_flags & PQ_SWAPBACKED) != 0; 736 if (!swap) { 737 uobj = pg->uobject; 738 } 739 } 740 KASSERT(swap || pg->uobject == uobj); 741 742 /* 743 * if this is a read and we got an error, mark the pages 744 * PG_RELEASED so that uvm_page_unbusy() will free them. 745 */ 746 if (!write && error) { 747 atomic_setbits_int(&pg->pg_flags, PG_RELEASED); 748 continue; 749 } 750 KASSERT(!write || (pgs[i]->pg_flags & PG_FAKE) == 0); 751 752 /* 753 * if this is a read and the page is PG_FAKE, 754 * or this was a successful write, 755 * mark the page PG_CLEAN and not PG_FAKE. 756 */ 757 if ((pgs[i]->pg_flags & PG_FAKE) || (write && error != ENOMEM)) { 758 pmap_clear_reference(pgs[i]); 759 pmap_clear_modify(pgs[i]); 760 atomic_setbits_int(&pgs[i]->pg_flags, PG_CLEAN); 761 atomic_clearbits_int(&pgs[i]->pg_flags, PG_FAKE); 762 } 763 } 764 uvm_page_unbusy(pgs, npages); 765 766 #ifdef UVM_SWAP_ENCRYPT 767 freed: 768 #endif 769 pool_put(&bufpool, bp); 770 } 771