vnode_pager.c revision 32071
1/* 2 * Copyright (c) 1990 University of Utah. 3 * Copyright (c) 1991 The Regents of the University of California. 4 * All rights reserved. 5 * Copyright (c) 1993, 1994 John S. Dyson 6 * Copyright (c) 1995, David Greenman 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the Systems Programming Group of the University of Utah Computer 10 * Science Department. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * from: @(#)vnode_pager.c 7.5 (Berkeley) 4/20/91 41 * $Id: vnode_pager.c,v 1.77 1997/12/19 09:03:17 dyson Exp $ 42 */ 43 44/* 45 * Page to/from files (vnodes). 46 */ 47 48/* 49 * TODO: 50 * Implement VOP_GETPAGES/PUTPAGES interface for filesystems. Will 51 * greatly re-simplify the vnode_pager. 52 */ 53 54#include <sys/param.h> 55#include <sys/systm.h> 56#include <sys/proc.h> 57#include <sys/vnode.h> 58#include <sys/mount.h> 59#include <sys/buf.h> 60#include <sys/vmmeter.h> 61 62#include <vm/vm.h> 63#include <vm/vm_prot.h> 64#include <vm/vm_object.h> 65#include <vm/vm_page.h> 66#include <vm/vm_pager.h> 67#include <vm/vm_map.h> 68#include <vm/vnode_pager.h> 69#include <vm/vm_extern.h> 70 71static vm_offset_t vnode_pager_addr __P((struct vnode *vp, vm_ooffset_t address, 72 int *run)); 73static void vnode_pager_iodone __P((struct buf *bp)); 74static int vnode_pager_input_smlfs __P((vm_object_t object, vm_page_t m)); 75static int vnode_pager_input_old __P((vm_object_t object, vm_page_t m)); 76static void vnode_pager_dealloc __P((vm_object_t)); 77static int vnode_pager_getpages __P((vm_object_t, vm_page_t *, int, int)); 78static int vnode_pager_putpages __P((vm_object_t, vm_page_t *, int, boolean_t, int *)); 79static boolean_t vnode_pager_haspage __P((vm_object_t, vm_pindex_t, int *, int *)); 80 81struct pagerops vnodepagerops = { 82 NULL, 83 vnode_pager_alloc, 84 vnode_pager_dealloc, 85 vnode_pager_getpages, 86 vnode_pager_putpages, 87 vnode_pager_haspage, 88 NULL 89}; 90 91static int vnode_pager_leaf_getpages __P((vm_object_t object, vm_page_t *m, 92 int count, int reqpage)); 93static int vnode_pager_leaf_putpages __P((vm_object_t object, vm_page_t *m, 94 int count, boolean_t sync, 95 int *rtvals)); 96 97/* 98 * Allocate (or lookup) pager for a vnode. 99 * Handle is a vnode pointer. 100 */ 101vm_object_t 102vnode_pager_alloc(void *handle, vm_size_t size, vm_prot_t prot, 103 vm_ooffset_t offset) 104{ 105 vm_object_t object; 106 struct vnode *vp; 107 108 /* 109 * Pageout to vnode, no can do yet. 110 */ 111 if (handle == NULL) 112 return (NULL); 113 114 vp = (struct vnode *) handle; 115 116 /* 117 * Prevent race condition when allocating the object. This 118 * can happen with NFS vnodes since the nfsnode isn't locked. 119 */ 120 while (vp->v_flag & VOLOCK) { 121 vp->v_flag |= VOWANT; 122 tsleep(vp, PVM, "vnpobj", 0); 123 } 124 vp->v_flag |= VOLOCK; 125 126 /* 127 * If the object is being terminated, wait for it to 128 * go away. 129 */ 130 while (((object = vp->v_object) != NULL) && 131 (object->flags & OBJ_DEAD)) { 132 tsleep(object, PVM, "vadead", 0); 133 } 134 135 if (vp->v_usecount == 0) 136 panic("vnode_pager_alloc: no vnode reference"); 137 138 if (object == NULL) { 139 /* 140 * And an object of the appropriate size 141 */ 142 object = vm_object_allocate(OBJT_VNODE, size); 143 if (vp->v_type == VREG) 144 object->flags = OBJ_CANPERSIST; 145 else 146 object->flags = 0; 147 148 object->un_pager.vnp.vnp_size = (vm_ooffset_t) size * PAGE_SIZE; 149 150 object->handle = handle; 151 vp->v_object = object; 152 } else { 153 /* 154 * vm_object_reference() will remove the object from the cache if 155 * found and gain a reference to the object. 156 */ 157 vm_object_reference(object); 158 } 159 160 if (vp->v_type == VREG) 161 vp->v_flag |= VVMIO; 162 163 vp->v_flag &= ~VOLOCK; 164 if (vp->v_flag & VOWANT) { 165 vp->v_flag &= ~VOWANT; 166 wakeup(vp); 167 } 168 return (object); 169} 170 171static void 172vnode_pager_dealloc(object) 173 vm_object_t object; 174{ 175 register struct vnode *vp = object->handle; 176 177 if (vp == NULL) 178 panic("vnode_pager_dealloc: pager already dealloced"); 179 180 if (object->paging_in_progress) { 181 int s = splbio(); 182 while (object->paging_in_progress) { 183 object->flags |= OBJ_PIPWNT; 184 tsleep(object, PVM, "vnpdea", 0); 185 } 186 splx(s); 187 } 188 189 object->handle = NULL; 190 191 vp->v_object = NULL; 192 vp->v_flag &= ~(VTEXT | VVMIO); 193} 194 195static boolean_t 196vnode_pager_haspage(object, pindex, before, after) 197 vm_object_t object; 198 vm_pindex_t pindex; 199 int *before; 200 int *after; 201{ 202 struct vnode *vp = object->handle; 203 daddr_t bn; 204 int err; 205 daddr_t reqblock; 206 int poff; 207 int bsize; 208 int pagesperblock, blocksperpage; 209 210 /* 211 * If filesystem no longer mounted or offset beyond end of file we do 212 * not have the page. 213 */ 214 if ((vp->v_mount == NULL) || 215 (IDX_TO_OFF(pindex) >= object->un_pager.vnp.vnp_size)) 216 return FALSE; 217 218 bsize = vp->v_mount->mnt_stat.f_iosize; 219 pagesperblock = bsize / PAGE_SIZE; 220 blocksperpage = 0; 221 if (pagesperblock > 0) { 222 reqblock = pindex / pagesperblock; 223 } else { 224 blocksperpage = (PAGE_SIZE / bsize); 225 reqblock = pindex * blocksperpage; 226 } 227 err = VOP_BMAP(vp, reqblock, (struct vnode **) 0, &bn, 228 after, before); 229 if (err) 230 return TRUE; 231 if ( bn == -1) 232 return FALSE; 233 if (pagesperblock > 0) { 234 poff = pindex - (reqblock * pagesperblock); 235 if (before) { 236 *before *= pagesperblock; 237 *before += poff; 238 } 239 if (after) { 240 int numafter; 241 *after *= pagesperblock; 242 numafter = pagesperblock - (poff + 1); 243 if (IDX_TO_OFF(pindex + numafter) > object->un_pager.vnp.vnp_size) { 244 numafter = OFF_TO_IDX((object->un_pager.vnp.vnp_size - IDX_TO_OFF(pindex))); 245 } 246 *after += numafter; 247 } 248 } else { 249 if (before) { 250 *before /= blocksperpage; 251 } 252 253 if (after) { 254 *after /= blocksperpage; 255 } 256 } 257 return TRUE; 258} 259 260/* 261 * Lets the VM system know about a change in size for a file. 262 * We adjust our own internal size and flush any cached pages in 263 * the associated object that are affected by the size change. 264 * 265 * Note: this routine may be invoked as a result of a pager put 266 * operation (possibly at object termination time), so we must be careful. 267 */ 268void 269vnode_pager_setsize(vp, nsize) 270 struct vnode *vp; 271 vm_ooffset_t nsize; 272{ 273 vm_object_t object = vp->v_object; 274 275 if (object == NULL) 276 return; 277 278 /* 279 * Hasn't changed size 280 */ 281 if (nsize == object->un_pager.vnp.vnp_size) 282 return; 283 284 /* 285 * File has shrunk. Toss any cached pages beyond the new EOF. 286 */ 287 if (nsize < object->un_pager.vnp.vnp_size) { 288 vm_ooffset_t nsizerounded; 289 nsizerounded = IDX_TO_OFF(OFF_TO_IDX(nsize + PAGE_MASK)); 290 if (nsizerounded < object->un_pager.vnp.vnp_size) { 291 vm_pindex_t st, end; 292 st = OFF_TO_IDX(nsize + PAGE_MASK); 293 end = OFF_TO_IDX(object->un_pager.vnp.vnp_size); 294 295 vm_freeze_copyopts(object, OFF_TO_IDX(nsize), object->size); 296 vm_object_page_remove(object, st, end, FALSE); 297 } 298 /* 299 * this gets rid of garbage at the end of a page that is now 300 * only partially backed by the vnode... 301 */ 302 if (nsize & PAGE_MASK) { 303 vm_offset_t kva; 304 vm_page_t m; 305 306 m = vm_page_lookup(object, OFF_TO_IDX(nsize)); 307 if (m) { 308 kva = vm_pager_map_page(m); 309 bzero((caddr_t) kva + (nsize & PAGE_MASK), 310 (int) (round_page(nsize) - nsize)); 311 vm_pager_unmap_page(kva); 312 } 313 } 314 } 315 object->un_pager.vnp.vnp_size = nsize; 316 object->size = OFF_TO_IDX(nsize + PAGE_MASK); 317} 318 319void 320vnode_pager_freepage(m) 321 vm_page_t m; 322{ 323 PAGE_WAKEUP(m); 324 vm_page_free(m); 325} 326 327/* 328 * calculate the linear (byte) disk address of specified virtual 329 * file address 330 */ 331static vm_offset_t 332vnode_pager_addr(vp, address, run) 333 struct vnode *vp; 334 vm_ooffset_t address; 335 int *run; 336{ 337 int rtaddress; 338 int bsize; 339 daddr_t block; 340 struct vnode *rtvp; 341 int err; 342 daddr_t vblock; 343 int voffset; 344 345 if ((int) address < 0) 346 return -1; 347 348 if (vp->v_mount == NULL) 349 return -1; 350 351 bsize = vp->v_mount->mnt_stat.f_iosize; 352 vblock = address / bsize; 353 voffset = address % bsize; 354 355 err = VOP_BMAP(vp, vblock, &rtvp, &block, run, NULL); 356 357 if (err || (block == -1)) 358 rtaddress = -1; 359 else { 360 rtaddress = block + voffset / DEV_BSIZE; 361 if( run) { 362 *run += 1; 363 *run *= bsize/PAGE_SIZE; 364 *run -= voffset/PAGE_SIZE; 365 } 366 } 367 368 return rtaddress; 369} 370 371/* 372 * interrupt routine for I/O completion 373 */ 374static void 375vnode_pager_iodone(bp) 376 struct buf *bp; 377{ 378 bp->b_flags |= B_DONE; 379 wakeup(bp); 380} 381 382/* 383 * small block file system vnode pager input 384 */ 385static int 386vnode_pager_input_smlfs(object, m) 387 vm_object_t object; 388 vm_page_t m; 389{ 390 int i; 391 int s; 392 struct vnode *dp, *vp; 393 struct buf *bp; 394 vm_offset_t kva; 395 int fileaddr; 396 vm_offset_t bsize; 397 int error = 0; 398 399 vp = object->handle; 400 if (vp->v_mount == NULL) 401 return VM_PAGER_BAD; 402 403 bsize = vp->v_mount->mnt_stat.f_iosize; 404 405 406 VOP_BMAP(vp, 0, &dp, 0, NULL, NULL); 407 408 kva = vm_pager_map_page(m); 409 410 for (i = 0; i < PAGE_SIZE / bsize; i++) { 411 412 if ((vm_page_bits(IDX_TO_OFF(m->pindex) + i * bsize, bsize) & m->valid)) 413 continue; 414 415 fileaddr = vnode_pager_addr(vp, 416 IDX_TO_OFF(m->pindex) + i * bsize, (int *)0); 417 if (fileaddr != -1) { 418 bp = getpbuf(); 419 420 /* build a minimal buffer header */ 421 bp->b_flags = B_BUSY | B_READ | B_CALL; 422 bp->b_iodone = vnode_pager_iodone; 423 bp->b_proc = curproc; 424 bp->b_rcred = bp->b_wcred = bp->b_proc->p_ucred; 425 if (bp->b_rcred != NOCRED) 426 crhold(bp->b_rcred); 427 if (bp->b_wcred != NOCRED) 428 crhold(bp->b_wcred); 429 bp->b_data = (caddr_t) kva + i * bsize; 430 bp->b_blkno = fileaddr; 431 pbgetvp(dp, bp); 432 bp->b_bcount = bsize; 433 bp->b_bufsize = bsize; 434 435 /* do the input */ 436 VOP_STRATEGY(bp); 437 438 /* we definitely need to be at splbio here */ 439 440 s = splbio(); 441 while ((bp->b_flags & B_DONE) == 0) { 442 tsleep(bp, PVM, "vnsrd", 0); 443 } 444 splx(s); 445 if ((bp->b_flags & B_ERROR) != 0) 446 error = EIO; 447 448 /* 449 * free the buffer header back to the swap buffer pool 450 */ 451 relpbuf(bp); 452 if (error) 453 break; 454 455 vm_page_set_validclean(m, (i * bsize) & PAGE_MASK, bsize); 456 } else { 457 vm_page_set_validclean(m, (i * bsize) & PAGE_MASK, bsize); 458 bzero((caddr_t) kva + i * bsize, bsize); 459 } 460 } 461 vm_pager_unmap_page(kva); 462 pmap_clear_modify(VM_PAGE_TO_PHYS(m)); 463 m->flags &= ~PG_ZERO; 464 if (error) { 465 return VM_PAGER_ERROR; 466 } 467 return VM_PAGER_OK; 468 469} 470 471 472/* 473 * old style vnode pager output routine 474 */ 475static int 476vnode_pager_input_old(object, m) 477 vm_object_t object; 478 vm_page_t m; 479{ 480 struct uio auio; 481 struct iovec aiov; 482 int error; 483 int size; 484 vm_offset_t kva; 485 486 error = 0; 487 488 /* 489 * Return failure if beyond current EOF 490 */ 491 if (IDX_TO_OFF(m->pindex) >= object->un_pager.vnp.vnp_size) { 492 return VM_PAGER_BAD; 493 } else { 494 size = PAGE_SIZE; 495 if (IDX_TO_OFF(m->pindex) + size > object->un_pager.vnp.vnp_size) 496 size = object->un_pager.vnp.vnp_size - IDX_TO_OFF(m->pindex); 497 498 /* 499 * Allocate a kernel virtual address and initialize so that 500 * we can use VOP_READ/WRITE routines. 501 */ 502 kva = vm_pager_map_page(m); 503 504 aiov.iov_base = (caddr_t) kva; 505 aiov.iov_len = size; 506 auio.uio_iov = &aiov; 507 auio.uio_iovcnt = 1; 508 auio.uio_offset = IDX_TO_OFF(m->pindex); 509 auio.uio_segflg = UIO_SYSSPACE; 510 auio.uio_rw = UIO_READ; 511 auio.uio_resid = size; 512 auio.uio_procp = (struct proc *) 0; 513 514 error = VOP_READ(object->handle, &auio, 0, curproc->p_ucred); 515 if (!error) { 516 register int count = size - auio.uio_resid; 517 518 if (count == 0) 519 error = EINVAL; 520 else if (count != PAGE_SIZE) 521 bzero((caddr_t) kva + count, PAGE_SIZE - count); 522 } 523 vm_pager_unmap_page(kva); 524 } 525 pmap_clear_modify(VM_PAGE_TO_PHYS(m)); 526 m->dirty = 0; 527 m->flags &= ~PG_ZERO; 528 return error ? VM_PAGER_ERROR : VM_PAGER_OK; 529} 530 531/* 532 * generic vnode pager input routine 533 */ 534 535static int 536vnode_pager_getpages(object, m, count, reqpage) 537 vm_object_t object; 538 vm_page_t *m; 539 int count; 540 int reqpage; 541{ 542 int rtval; 543 struct vnode *vp; 544 if (object->flags & OBJ_VNODE_GONE) 545 return VM_PAGER_ERROR; 546 vp = object->handle; 547 rtval = VOP_GETPAGES(vp, m, count*PAGE_SIZE, reqpage, 0); 548 if (rtval == EOPNOTSUPP) 549 return vnode_pager_leaf_getpages(object, m, count, reqpage); 550 else 551 return rtval; 552} 553 554static int 555vnode_pager_leaf_getpages(object, m, count, reqpage) 556 vm_object_t object; 557 vm_page_t *m; 558 int count; 559 int reqpage; 560{ 561 vm_offset_t kva; 562 off_t foff; 563 int i, size, bsize, first, firstaddr; 564 struct vnode *dp, *vp; 565 int runpg; 566 int runend; 567 struct buf *bp; 568 int s; 569 int error = 0; 570 571 vp = object->handle; 572 if (vp->v_mount == NULL) 573 return VM_PAGER_BAD; 574 575 bsize = vp->v_mount->mnt_stat.f_iosize; 576 577 /* get the UNDERLYING device for the file with VOP_BMAP() */ 578 579 /* 580 * originally, we did not check for an error return value -- assuming 581 * an fs always has a bmap entry point -- that assumption is wrong!!! 582 */ 583 foff = IDX_TO_OFF(m[reqpage]->pindex); 584 585 /* 586 * if we can't bmap, use old VOP code 587 */ 588 if (VOP_BMAP(vp, 0, &dp, 0, NULL, NULL)) { 589 for (i = 0; i < count; i++) { 590 if (i != reqpage) { 591 vnode_pager_freepage(m[i]); 592 } 593 } 594 cnt.v_vnodein++; 595 cnt.v_vnodepgsin++; 596 return vnode_pager_input_old(object, m[reqpage]); 597 598 /* 599 * if the blocksize is smaller than a page size, then use 600 * special small filesystem code. NFS sometimes has a small 601 * blocksize, but it can handle large reads itself. 602 */ 603 } else if ((PAGE_SIZE / bsize) > 1 && 604 (vp->v_mount->mnt_stat.f_type != MOUNT_NFS)) { 605 606 for (i = 0; i < count; i++) { 607 if (i != reqpage) { 608 vnode_pager_freepage(m[i]); 609 } 610 } 611 cnt.v_vnodein++; 612 cnt.v_vnodepgsin++; 613 return vnode_pager_input_smlfs(object, m[reqpage]); 614 } 615 /* 616 * if ANY DEV_BSIZE blocks are valid on a large filesystem block 617 * then, the entire page is valid -- 618 * XXX no it isn't 619 */ 620 621 if (m[reqpage]->valid != VM_PAGE_BITS_ALL) 622 m[reqpage]->valid = 0; 623 624 if (m[reqpage]->valid) { 625 m[reqpage]->valid = VM_PAGE_BITS_ALL; 626 for (i = 0; i < count; i++) { 627 if (i != reqpage) 628 vnode_pager_freepage(m[i]); 629 } 630 return VM_PAGER_OK; 631 } 632 633 /* 634 * here on direct device I/O 635 */ 636 637 firstaddr = -1; 638 /* 639 * calculate the run that includes the required page 640 */ 641 for(first = 0, i = 0; i < count; i = runend) { 642 firstaddr = vnode_pager_addr(vp, 643 IDX_TO_OFF(m[i]->pindex), &runpg); 644 if (firstaddr == -1) { 645 if (i == reqpage && foff < object->un_pager.vnp.vnp_size) { 646 panic("vnode_pager_putpages: unexpected missing page: firstaddr: %d, foff: %ld, vnp_size: %d", 647 firstaddr, foff, object->un_pager.vnp.vnp_size); 648 } 649 vnode_pager_freepage(m[i]); 650 runend = i + 1; 651 first = runend; 652 continue; 653 } 654 runend = i + runpg; 655 if (runend <= reqpage) { 656 int j; 657 for (j = i; j < runend; j++) { 658 vnode_pager_freepage(m[j]); 659 } 660 } else { 661 if (runpg < (count - first)) { 662 for (i = first + runpg; i < count; i++) 663 vnode_pager_freepage(m[i]); 664 count = first + runpg; 665 } 666 break; 667 } 668 first = runend; 669 } 670 671 /* 672 * the first and last page have been calculated now, move input pages 673 * to be zero based... 674 */ 675 if (first != 0) { 676 for (i = first; i < count; i++) { 677 m[i - first] = m[i]; 678 } 679 count -= first; 680 reqpage -= first; 681 } 682 683 /* 684 * calculate the file virtual address for the transfer 685 */ 686 foff = IDX_TO_OFF(m[0]->pindex); 687 688 /* 689 * calculate the size of the transfer 690 */ 691 size = count * PAGE_SIZE; 692 if ((foff + size) > object->un_pager.vnp.vnp_size) 693 size = object->un_pager.vnp.vnp_size - foff; 694 695 /* 696 * round up physical size for real devices 697 */ 698 if (dp->v_type == VBLK || dp->v_type == VCHR) 699 size = (size + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1); 700 701 bp = getpbuf(); 702 kva = (vm_offset_t) bp->b_data; 703 704 /* 705 * and map the pages to be read into the kva 706 */ 707 pmap_qenter(kva, m, count); 708 709 /* build a minimal buffer header */ 710 bp->b_flags = B_BUSY | B_READ | B_CALL; 711 bp->b_iodone = vnode_pager_iodone; 712 /* B_PHYS is not set, but it is nice to fill this in */ 713 bp->b_proc = curproc; 714 bp->b_rcred = bp->b_wcred = bp->b_proc->p_ucred; 715 if (bp->b_rcred != NOCRED) 716 crhold(bp->b_rcred); 717 if (bp->b_wcred != NOCRED) 718 crhold(bp->b_wcred); 719 bp->b_blkno = firstaddr; 720 pbgetvp(dp, bp); 721 bp->b_bcount = size; 722 bp->b_bufsize = size; 723 724 cnt.v_vnodein++; 725 cnt.v_vnodepgsin += count; 726 727 /* do the input */ 728 VOP_STRATEGY(bp); 729 730 s = splbio(); 731 /* we definitely need to be at splbio here */ 732 733 while ((bp->b_flags & B_DONE) == 0) { 734 tsleep(bp, PVM, "vnread", 0); 735 } 736 splx(s); 737 if ((bp->b_flags & B_ERROR) != 0) 738 error = EIO; 739 740 if (!error) { 741 if (size != count * PAGE_SIZE) 742 bzero((caddr_t) kva + size, PAGE_SIZE * count - size); 743 } 744 pmap_qremove(kva, count); 745 746 /* 747 * free the buffer header back to the swap buffer pool 748 */ 749 relpbuf(bp); 750 751 for (i = 0; i < count; i++) { 752 pmap_clear_modify(VM_PAGE_TO_PHYS(m[i])); 753 m[i]->dirty = 0; 754 m[i]->valid = VM_PAGE_BITS_ALL; 755 m[i]->flags &= ~PG_ZERO; 756 if (i != reqpage) { 757 758 /* 759 * whether or not to leave the page activated is up in 760 * the air, but we should put the page on a page queue 761 * somewhere. (it already is in the object). Result: 762 * It appears that emperical results show that 763 * deactivating pages is best. 764 */ 765 766 /* 767 * just in case someone was asking for this page we 768 * now tell them that it is ok to use 769 */ 770 if (!error) { 771 vm_page_deactivate(m[i]); 772 PAGE_WAKEUP(m[i]); 773 } else { 774 vnode_pager_freepage(m[i]); 775 } 776 } 777 } 778 if (error) { 779 printf("vnode_pager_getpages: I/O read error\n"); 780 } 781 return (error ? VM_PAGER_ERROR : VM_PAGER_OK); 782} 783 784static int 785vnode_pager_putpages(object, m, count, sync, rtvals) 786 vm_object_t object; 787 vm_page_t *m; 788 int count; 789 boolean_t sync; 790 int *rtvals; 791{ 792 int rtval; 793 struct vnode *vp; 794 795 if (object->flags & OBJ_VNODE_GONE) 796 return VM_PAGER_ERROR; 797 798 vp = object->handle; 799 rtval = VOP_PUTPAGES(vp, m, count*PAGE_SIZE, sync, rtvals, 0); 800 if (rtval == EOPNOTSUPP) 801 return vnode_pager_leaf_putpages(object, m, count, sync, rtvals); 802 else 803 return rtval; 804} 805 806/* 807 * generic vnode pager output routine 808 */ 809static int 810vnode_pager_leaf_putpages(object, m, count, sync, rtvals) 811 vm_object_t object; 812 vm_page_t *m; 813 int count; 814 boolean_t sync; 815 int *rtvals; 816{ 817 int i; 818 819 struct vnode *vp; 820 int maxsize, ncount; 821 vm_ooffset_t poffset; 822 struct uio auio; 823 struct iovec aiov; 824 int error; 825 826 vp = object->handle;; 827 for (i = 0; i < count; i++) 828 rtvals[i] = VM_PAGER_AGAIN; 829 830 if ((int) m[0]->pindex < 0) { 831 printf("vnode_pager_putpages: attempt to write meta-data!!! -- 0x%x(%x)\n", m[0]->pindex, m[0]->dirty); 832 rtvals[0] = VM_PAGER_BAD; 833 return VM_PAGER_BAD; 834 } 835 836 maxsize = count * PAGE_SIZE; 837 ncount = count; 838 839 poffset = IDX_TO_OFF(m[0]->pindex); 840 if (maxsize + poffset > object->un_pager.vnp.vnp_size) { 841 if (object->un_pager.vnp.vnp_size > poffset) 842 maxsize = object->un_pager.vnp.vnp_size - poffset; 843 else 844 maxsize = 0; 845 ncount = btoc(maxsize); 846 if (ncount < count) { 847 for (i = ncount; i < count; i++) { 848 rtvals[i] = VM_PAGER_BAD; 849 } 850#ifdef BOGUS 851 if (ncount == 0) { 852 printf("vnode_pager_putpages: write past end of file: %d, %lu\n", 853 poffset, 854 (unsigned long) object->un_pager.vnp.vnp_size); 855 return rtvals[0]; 856 } 857#endif 858 } 859 } 860 861 for (i = 0; i < count; i++) { 862 m[i]->busy++; 863 m[i]->flags &= ~PG_BUSY; 864 } 865 866 aiov.iov_base = (caddr_t) 0; 867 aiov.iov_len = maxsize; 868 auio.uio_iov = &aiov; 869 auio.uio_iovcnt = 1; 870 auio.uio_offset = poffset; 871 auio.uio_segflg = UIO_NOCOPY; 872 auio.uio_rw = UIO_WRITE; 873 auio.uio_resid = maxsize; 874 auio.uio_procp = (struct proc *) 0; 875 error = VOP_WRITE(vp, &auio, IO_VMIO|(sync?IO_SYNC:0), curproc->p_ucred); 876 cnt.v_vnodeout++; 877 cnt.v_vnodepgsout += ncount; 878 879 if (error) { 880 printf("vnode_pager_putpages: I/O error %d\n", error); 881 } 882 if (auio.uio_resid) { 883 printf("vnode_pager_putpages: residual I/O %d at %ld\n", 884 auio.uio_resid, m[0]->pindex); 885 } 886 for (i = 0; i < count; i++) { 887 m[i]->busy--; 888 if (i < ncount) { 889 rtvals[i] = VM_PAGER_OK; 890 } 891 if ((m[i]->busy == 0) && (m[i]->flags & PG_WANTED)) 892 wakeup(m[i]); 893 } 894 return rtvals[0]; 895} 896 897struct vnode * 898vnode_pager_lock(object) 899 vm_object_t object; 900{ 901 struct proc *p = curproc; /* XXX */ 902 903 for (; object != NULL; object = object->backing_object) { 904 if (object->type != OBJT_VNODE) 905 continue; 906 907 vn_lock(object->handle, 908 LK_NOPAUSE | LK_SHARED | LK_RETRY | LK_CANRECURSE, p); 909 return object->handle; 910 } 911 return NULL; 912} 913