1 /*- 2 * Copyright (c) 1993 3 * The Regents of the University of California. All rights reserved. 4 * Modifications/enhancements: 5 * Copyright (c) 1995 John S. Dyson. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)vfs_cluster.c 8.7 (Berkeley) 2/13/94 36 * $Id: vfs_cluster.c,v 1.36 1996/06/03 04:40:35 dyson Exp $ 37 */ 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/proc.h> 42 #include <sys/buf.h> 43 #include <sys/vnode.h> 44 #include <sys/mount.h> 45 #include <sys/malloc.h> 46 #include <sys/resourcevar.h> 47 #include <sys/vmmeter.h> 48 #include <miscfs/specfs/specdev.h> 49 #include <vm/vm.h> 50 #include <vm/vm_param.h> 51 #include <vm/vm_prot.h> 52 #include <vm/vm_object.h> 53 #include <vm/vm_page.h> 54 55 #ifdef notyet_block_reallocation_enabled 56 #ifdef DEBUG 57 #include <sys/sysctl.h> 58 #include <sys/kernel.h> 59 60 static int doreallocblks = 0; 61 SYSCTL_INT(_debug, 13, doreallocblks, CTLFLAG_RW, &doreallocblks, 0, ""); 62 #else 63 #define doreallocblks 0 64 #endif 65 #endif /* notyet_block_reallocation_enabled */ 66 67 #ifdef notyet_block_reallocation_enabled 68 static struct cluster_save * 69 cluster_collectbufs __P((struct vnode *vp, struct buf *last_bp)); 70 #endif 71 static struct buf * 72 cluster_rbuild __P((struct vnode *vp, u_quad_t filesize, daddr_t lbn, 73 daddr_t blkno, long size, int run)); 74 75 static int totreads; 76 static int totreadblocks; 77 extern vm_page_t bogus_page; 78 79 #ifdef DIAGNOSTIC 80 /* 81 * Set to 1 if reads of block zero should cause readahead to be done. 82 * Set to 0 treats a read of block zero as a non-sequential read. 83 * 84 * Setting to one assumes that most reads of block zero of files are due to 85 * sequential passes over the files (e.g. cat, sum) where additional blocks 86 * will soon be needed. Setting to zero assumes that the majority are 87 * surgical strikes to get particular info (e.g. size, file) where readahead 88 * blocks will not be used and, in fact, push out other potentially useful 89 * blocks from the cache. The former seems intuitive, but some quick tests 90 * showed that the latter performed better from a system-wide point of view. 91 */ 92 int doclusterraz = 0; 93 94 #define ISSEQREAD(vp, blk) \ 95 (((blk) != 0 || doclusterraz) && \ 96 ((blk) == (vp)->v_lastr + 1 || (blk) == (vp)->v_lastr)) 97 #else 98 #define ISSEQREAD(vp, blk) \ 99 (/* (blk) != 0 && */ ((blk) == (vp)->v_lastr + 1 || (blk) == (vp)->v_lastr)) 100 #endif 101 102 /* 103 * allow for three entire read-aheads... The system will 104 * adjust downwards rapidly if needed... 105 */ 106 #define RA_MULTIPLE_FAST 2 107 #define RA_MULTIPLE_SLOW 3 108 #define RA_SHIFTDOWN 1 /* approx lg2(RA_MULTIPLE) */ 109 /* 110 * This replaces bread. If this is a bread at the beginning of a file and 111 * lastr is 0, we assume this is the first read and we'll read up to two 112 * blocks if they are sequential. After that, we'll do regular read ahead 113 * in clustered chunks. 114 * bp is the block requested. 115 * rbp is the read-ahead block. 116 * If either is NULL, then you don't have to do the I/O. 117 */ 118 int 119 cluster_read(vp, filesize, lblkno, size, cred, bpp) 120 struct vnode *vp; 121 u_quad_t filesize; 122 daddr_t lblkno; 123 long size; 124 struct ucred *cred; 125 struct buf **bpp; 126 { 127 struct buf *bp, *rbp; 128 daddr_t blkno, rablkno, origlblkno; 129 int error, num_ra, alreadyincore; 130 int i; 131 int seq; 132 133 error = 0; 134 /* 135 * get the requested block 136 */ 137 origlblkno = lblkno; 138 *bpp = bp = getblk(vp, lblkno, size, 0, 0); 139 140 seq = ISSEQREAD(vp, lblkno); 141 /* 142 * if it is in the cache, then check to see if the reads have been 143 * sequential. If they have, then try some read-ahead, otherwise 144 * back-off on prospective read-aheads. 145 */ 146 if (bp->b_flags & B_CACHE) { 147 if (!seq) { 148 vp->v_maxra = bp->b_lblkno + bp->b_bcount / size; 149 vp->v_ralen >>= RA_SHIFTDOWN; 150 return 0; 151 } else if( vp->v_maxra > lblkno) { 152 if ((vp->v_ralen + 1) < RA_MULTIPLE_FAST * (MAXPHYS / size)) 153 ++vp->v_ralen; 154 if ( vp->v_maxra > lblkno + vp->v_ralen ) { 155 return 0; 156 } 157 lblkno = vp->v_maxra; 158 } else { 159 lblkno += 1; 160 } 161 bp = NULL; 162 } else { 163 /* 164 * if it isn't in the cache, then get a chunk from disk if 165 * sequential, otherwise just get the block. 166 */ 167 bp->b_flags |= B_READ; 168 lblkno += 1; 169 curproc->p_stats->p_ru.ru_inblock++; /* XXX */ 170 vp->v_ralen = 0; 171 } 172 /* 173 * assume no read-ahead 174 */ 175 alreadyincore = 1; 176 rablkno = lblkno; 177 178 /* 179 * if we have been doing sequential I/O, then do some read-ahead 180 */ 181 if (seq) { 182 alreadyincore = 0; 183 184 /* 185 * bump ralen a bit... 186 */ 187 if ((vp->v_ralen + 1) < RA_MULTIPLE_SLOW*(MAXPHYS / size)) 188 ++vp->v_ralen; 189 /* 190 * this code makes sure that the stuff that we have read-ahead 191 * is still in the cache. If it isn't, we have been reading 192 * ahead too much, and we need to back-off, otherwise we might 193 * try to read more. 194 */ 195 for (i = 0; i < vp->v_maxra - lblkno; i++) { 196 rablkno = lblkno + i; 197 alreadyincore = (int) incore(vp, rablkno); 198 if (!alreadyincore) { 199 vp->v_maxra = rablkno; 200 vp->v_ralen >>= RA_SHIFTDOWN; 201 alreadyincore = 1; 202 } 203 } 204 } 205 /* 206 * we now build the read-ahead buffer if it is desirable. 207 */ 208 rbp = NULL; 209 if (!alreadyincore && 210 ((u_quad_t)(rablkno + 1) * size) <= filesize && 211 !(error = VOP_BMAP(vp, rablkno, NULL, &blkno, &num_ra, NULL)) && 212 blkno != -1) { 213 if (num_ra > vp->v_ralen) 214 num_ra = vp->v_ralen; 215 216 if (num_ra) { 217 rbp = cluster_rbuild(vp, filesize, rablkno, blkno, size, 218 num_ra + 1); 219 } else { 220 rbp = getblk(vp, rablkno, size, 0, 0); 221 rbp->b_flags |= B_READ | B_ASYNC; 222 rbp->b_blkno = blkno; 223 } 224 } 225 226 /* 227 * handle the synchronous read 228 */ 229 if (bp) { 230 if (bp->b_flags & (B_DONE | B_DELWRI)) 231 panic("cluster_read: DONE bp"); 232 else { 233 vfs_busy_pages(bp, 0); 234 error = VOP_STRATEGY(bp); 235 vp->v_maxra = bp->b_lblkno + bp->b_bcount / size; 236 totreads++; 237 totreadblocks += bp->b_bcount / size; 238 curproc->p_stats->p_ru.ru_inblock++; 239 } 240 } 241 /* 242 * and if we have read-aheads, do them too 243 */ 244 if (rbp) { 245 vp->v_maxra = rbp->b_lblkno + rbp->b_bcount / size; 246 if (error) { 247 rbp->b_flags &= ~(B_ASYNC | B_READ); 248 brelse(rbp); 249 } else if (rbp->b_flags & B_CACHE) { 250 rbp->b_flags &= ~(B_ASYNC | B_READ); 251 bqrelse(rbp); 252 } else { 253 if ((rbp->b_flags & B_CLUSTER) == 0) 254 vfs_busy_pages(rbp, 0); 255 (void) VOP_STRATEGY(rbp); 256 totreads++; 257 totreadblocks += rbp->b_bcount / size; 258 curproc->p_stats->p_ru.ru_inblock++; 259 } 260 } 261 if (bp && ((bp->b_flags & B_ASYNC) == 0)) 262 return (biowait(bp)); 263 return (error); 264 } 265 266 /* 267 * If blocks are contiguous on disk, use this to provide clustered 268 * read ahead. We will read as many blocks as possible sequentially 269 * and then parcel them up into logical blocks in the buffer hash table. 270 */ 271 static struct buf * 272 cluster_rbuild(vp, filesize, lbn, blkno, size, run) 273 struct vnode *vp; 274 u_quad_t filesize; 275 daddr_t lbn; 276 daddr_t blkno; 277 long size; 278 int run; 279 { 280 struct buf *bp, *tbp; 281 daddr_t bn; 282 int i, inc, j; 283 284 #ifdef DIAGNOSTIC 285 if (size != vp->v_mount->mnt_stat.f_iosize) 286 panic("cluster_rbuild: size %d != filesize %d\n", 287 size, vp->v_mount->mnt_stat.f_iosize); 288 #endif 289 /* 290 * avoid a division 291 */ 292 while ((u_quad_t) size * (lbn + run) > filesize) { 293 --run; 294 } 295 296 tbp = getblk(vp, lbn, size, 0, 0); 297 if (tbp->b_flags & B_CACHE) 298 return tbp; 299 300 tbp->b_blkno = blkno; 301 tbp->b_flags |= B_ASYNC | B_READ; 302 if( (tbp->b_flags & B_MALLOC) || 303 ((tbp->b_flags & B_VMIO) == 0) || (run <= 1) ) 304 return tbp; 305 306 bp = trypbuf(); 307 if (bp == 0) 308 return tbp; 309 310 (vm_offset_t) bp->b_data |= ((vm_offset_t) tbp->b_data) & PAGE_MASK; 311 bp->b_flags = B_ASYNC | B_READ | B_CALL | B_BUSY | B_CLUSTER | B_VMIO; 312 bp->b_iodone = cluster_callback; 313 bp->b_blkno = blkno; 314 bp->b_lblkno = lbn; 315 pbgetvp(vp, bp); 316 317 TAILQ_INIT(&bp->b_cluster.cluster_head); 318 319 bp->b_bcount = 0; 320 bp->b_bufsize = 0; 321 bp->b_npages = 0; 322 323 inc = btodb(size); 324 for (bn = blkno, i = 0; i < run; ++i, bn += inc) { 325 if (i != 0) { 326 if ((bp->b_npages * PAGE_SIZE) + 327 round_page(size) > MAXPHYS) 328 break; 329 330 if (incore(vp, lbn + i)) 331 break; 332 333 tbp = getblk(vp, lbn + i, size, 0, 0); 334 335 if ((tbp->b_flags & B_CACHE) || 336 (tbp->b_flags & B_VMIO) == 0) { 337 bqrelse(tbp); 338 break; 339 } 340 341 for (j=0;j<tbp->b_npages;j++) { 342 if (tbp->b_pages[j]->valid) { 343 break; 344 } 345 } 346 347 if (j != tbp->b_npages) { 348 /* 349 * force buffer to be re-constituted later 350 */ 351 tbp->b_flags |= B_RELBUF; 352 brelse(tbp); 353 break; 354 } 355 356 tbp->b_flags |= B_READ | B_ASYNC; 357 if (tbp->b_blkno == tbp->b_lblkno) { 358 tbp->b_blkno = bn; 359 } else if (tbp->b_blkno != bn) { 360 brelse(tbp); 361 break; 362 } 363 } 364 TAILQ_INSERT_TAIL(&bp->b_cluster.cluster_head, 365 tbp, b_cluster.cluster_entry); 366 for (j = 0; j < tbp->b_npages; j += 1) { 367 vm_page_t m; 368 m = tbp->b_pages[j]; 369 ++m->busy; 370 ++m->object->paging_in_progress; 371 if ((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) { 372 m = bogus_page; 373 } 374 if ((bp->b_npages == 0) || 375 (bp->b_pages[bp->b_npages-1] != m)) { 376 bp->b_pages[bp->b_npages] = m; 377 bp->b_npages++; 378 } 379 } 380 bp->b_bcount += tbp->b_bcount; 381 bp->b_bufsize += tbp->b_bufsize; 382 } 383 pmap_qenter(trunc_page((vm_offset_t) bp->b_data), 384 (vm_page_t *)bp->b_pages, bp->b_npages); 385 return (bp); 386 } 387 388 /* 389 * Cleanup after a clustered read or write. 390 * This is complicated by the fact that any of the buffers might have 391 * extra memory (if there were no empty buffer headers at allocbuf time) 392 * that we will need to shift around. 393 */ 394 void 395 cluster_callback(bp) 396 struct buf *bp; 397 { 398 struct buf *nbp, *tbp; 399 int error = 0; 400 401 /* 402 * Must propogate errors to all the components. 403 */ 404 if (bp->b_flags & B_ERROR) 405 error = bp->b_error; 406 407 pmap_qremove(trunc_page((vm_offset_t) bp->b_data), bp->b_npages); 408 /* 409 * Move memory from the large cluster buffer into the component 410 * buffers and mark IO as done on these. 411 */ 412 for (tbp = bp->b_cluster.cluster_head.tqh_first; 413 tbp; tbp = nbp) { 414 nbp = tbp->b_cluster.cluster_entry.tqe_next; 415 if (error) { 416 tbp->b_flags |= B_ERROR; 417 tbp->b_error = error; 418 } 419 biodone(tbp); 420 } 421 relpbuf(bp); 422 } 423 424 /* 425 * Do clustered write for FFS. 426 * 427 * Three cases: 428 * 1. Write is not sequential (write asynchronously) 429 * Write is sequential: 430 * 2. beginning of cluster - begin cluster 431 * 3. middle of a cluster - add to cluster 432 * 4. end of a cluster - asynchronously write cluster 433 */ 434 void 435 cluster_write(bp, filesize) 436 struct buf *bp; 437 u_quad_t filesize; 438 { 439 struct vnode *vp; 440 daddr_t lbn; 441 int maxclen, cursize; 442 int lblocksize; 443 int async; 444 445 vp = bp->b_vp; 446 async = (vp->v_mount && (vp->v_mount->mnt_flag & MNT_ASYNC)); 447 lblocksize = vp->v_mount->mnt_stat.f_iosize; 448 lbn = bp->b_lblkno; 449 450 /* Initialize vnode to beginning of file. */ 451 if (lbn == 0) 452 vp->v_lasta = vp->v_clen = vp->v_cstart = vp->v_lastw = 0; 453 454 if (vp->v_clen == 0 || lbn != vp->v_lastw + 1 || 455 (bp->b_blkno != vp->v_lasta + btodb(lblocksize))) { 456 maxclen = MAXPHYS / lblocksize - 1; 457 if (vp->v_clen != 0) { 458 /* 459 * Next block is not sequential. 460 * 461 * If we are not writing at end of file, the process 462 * seeked to another point in the file since its last 463 * write, or we have reached our maximum cluster size, 464 * then push the previous cluster. Otherwise try 465 * reallocating to make it sequential. 466 */ 467 cursize = vp->v_lastw - vp->v_cstart + 1; 468 #ifndef notyet_block_reallocation_enabled 469 if (((u_quad_t)(lbn + 1) * lblocksize) != filesize || 470 lbn != vp->v_lastw + 1 || 471 vp->v_clen <= cursize) { 472 if (!async) 473 cluster_wbuild(vp, lblocksize, 474 vp->v_cstart, cursize); 475 } 476 #else 477 if (!doreallocblks || 478 (lbn + 1) * lblocksize != filesize || 479 lbn != vp->v_lastw + 1 || vp->v_clen <= cursize) { 480 if (!async) 481 cluster_wbuild(vp, lblocksize, 482 vp->v_cstart, cursize); 483 } else { 484 struct buf **bpp, **endbp; 485 struct cluster_save *buflist; 486 487 buflist = cluster_collectbufs(vp, bp); 488 endbp = &buflist->bs_children 489 [buflist->bs_nchildren - 1]; 490 if (VOP_REALLOCBLKS(vp, buflist)) { 491 /* 492 * Failed, push the previous cluster. 493 */ 494 for (bpp = buflist->bs_children; 495 bpp < endbp; bpp++) 496 brelse(*bpp); 497 free(buflist, M_SEGMENT); 498 cluster_wbuild(vp, lblocksize, 499 vp->v_cstart, cursize); 500 } else { 501 /* 502 * Succeeded, keep building cluster. 503 */ 504 for (bpp = buflist->bs_children; 505 bpp <= endbp; bpp++) 506 bdwrite(*bpp); 507 free(buflist, M_SEGMENT); 508 vp->v_lastw = lbn; 509 vp->v_lasta = bp->b_blkno; 510 return; 511 } 512 } 513 #endif /* notyet_block_reallocation_enabled */ 514 } 515 /* 516 * Consider beginning a cluster. If at end of file, make 517 * cluster as large as possible, otherwise find size of 518 * existing cluster. 519 */ 520 if (((u_quad_t) (lbn + 1) * lblocksize) != filesize && 521 (bp->b_blkno == bp->b_lblkno) && 522 (VOP_BMAP(vp, lbn, NULL, &bp->b_blkno, &maxclen, NULL) || 523 bp->b_blkno == -1)) { 524 bawrite(bp); 525 vp->v_clen = 0; 526 vp->v_lasta = bp->b_blkno; 527 vp->v_cstart = lbn + 1; 528 vp->v_lastw = lbn; 529 return; 530 } 531 vp->v_clen = maxclen; 532 if (!async && maxclen == 0) { /* I/O not contiguous */ 533 vp->v_cstart = lbn + 1; 534 bawrite(bp); 535 } else { /* Wait for rest of cluster */ 536 vp->v_cstart = lbn; 537 bdwrite(bp); 538 } 539 } else if (lbn == vp->v_cstart + vp->v_clen) { 540 /* 541 * At end of cluster, write it out. 542 */ 543 bdwrite(bp); 544 cluster_wbuild(vp, lblocksize, vp->v_cstart, vp->v_clen + 1); 545 vp->v_clen = 0; 546 vp->v_cstart = lbn + 1; 547 } else 548 /* 549 * In the middle of a cluster, so just delay the I/O for now. 550 */ 551 bdwrite(bp); 552 vp->v_lastw = lbn; 553 vp->v_lasta = bp->b_blkno; 554 } 555 556 557 /* 558 * This is an awful lot like cluster_rbuild...wish they could be combined. 559 * The last lbn argument is the current block on which I/O is being 560 * performed. Check to see that it doesn't fall in the middle of 561 * the current block (if last_bp == NULL). 562 */ 563 int 564 cluster_wbuild(vp, size, start_lbn, len) 565 struct vnode *vp; 566 long size; 567 daddr_t start_lbn; 568 int len; 569 { 570 struct buf *bp, *tbp; 571 int i, j, s; 572 int totalwritten = 0; 573 int dbsize = btodb(size); 574 while (len > 0) { 575 s = splbio(); 576 if ( ((tbp = gbincore(vp, start_lbn)) == NULL) || 577 ((tbp->b_flags & (B_INVAL|B_BUSY|B_DELWRI)) != B_DELWRI)) { 578 ++start_lbn; 579 --len; 580 splx(s); 581 continue; 582 } 583 bremfree(tbp); 584 tbp->b_flags |= B_BUSY; 585 tbp->b_flags &= ~B_DONE; 586 splx(s); 587 588 /* 589 * Extra memory in the buffer, punt on this buffer. XXX we could 590 * handle this in most cases, but we would have to push the extra 591 * memory down to after our max possible cluster size and then 592 * potentially pull it back up if the cluster was terminated 593 * prematurely--too much hassle. 594 */ 595 if (((tbp->b_flags & (B_CLUSTEROK|B_MALLOC)) != B_CLUSTEROK) || 596 (tbp->b_bcount != tbp->b_bufsize) || 597 (tbp->b_bcount != size) || 598 len == 1) { 599 totalwritten += tbp->b_bufsize; 600 bawrite(tbp); 601 ++start_lbn; 602 --len; 603 continue; 604 } 605 606 bp = trypbuf(); 607 if (bp == NULL) { 608 totalwritten += tbp->b_bufsize; 609 bawrite(tbp); 610 ++start_lbn; 611 --len; 612 continue; 613 } 614 615 TAILQ_INIT(&bp->b_cluster.cluster_head); 616 bp->b_bcount = 0; 617 bp->b_bufsize = 0; 618 bp->b_npages = 0; 619 if (tbp->b_wcred != NOCRED) { 620 bp->b_wcred = tbp->b_wcred; 621 crhold(bp->b_wcred); 622 } 623 624 bp->b_blkno = tbp->b_blkno; 625 bp->b_lblkno = tbp->b_lblkno; 626 (vm_offset_t) bp->b_data |= ((vm_offset_t) tbp->b_data) & PAGE_MASK; 627 bp->b_flags |= B_CALL | B_BUSY | B_CLUSTER | (tbp->b_flags & (B_VMIO|B_NEEDCOMMIT)); 628 bp->b_iodone = cluster_callback; 629 pbgetvp(vp, bp); 630 631 for (i = 0; i < len; ++i, ++start_lbn) { 632 if (i != 0) { 633 s = splbio(); 634 if ((tbp = gbincore(vp, start_lbn)) == NULL) { 635 splx(s); 636 break; 637 } 638 639 if ((tbp->b_flags & (B_VMIO|B_CLUSTEROK|B_INVAL|B_BUSY|B_DELWRI|B_NEEDCOMMIT)) != (B_DELWRI|B_CLUSTEROK|(bp->b_flags & (B_VMIO|B_NEEDCOMMIT)))) { 640 splx(s); 641 break; 642 } 643 644 if (tbp->b_wcred != bp->b_wcred) { 645 splx(s); 646 break; 647 } 648 649 if ((tbp->b_bcount != size) || 650 ((bp->b_blkno + dbsize * i) != tbp->b_blkno) || 651 ((tbp->b_npages + bp->b_npages) > (MAXPHYS / PAGE_SIZE))) { 652 splx(s); 653 break; 654 } 655 bremfree(tbp); 656 tbp->b_flags |= B_BUSY; 657 tbp->b_flags &= ~B_DONE; 658 splx(s); 659 } 660 if (tbp->b_flags & B_VMIO) { 661 for (j = 0; j < tbp->b_npages; j += 1) { 662 vm_page_t m; 663 m = tbp->b_pages[j]; 664 ++m->busy; 665 ++m->object->paging_in_progress; 666 if ((bp->b_npages == 0) || 667 (bp->b_pages[bp->b_npages - 1] != m)) { 668 bp->b_pages[bp->b_npages] = m; 669 bp->b_npages++; 670 } 671 } 672 } 673 bp->b_bcount += size; 674 bp->b_bufsize += size; 675 676 tbp->b_flags &= ~(B_READ | B_DONE | B_ERROR | B_DELWRI); 677 tbp->b_flags |= B_ASYNC; 678 s = splbio(); 679 reassignbuf(tbp, tbp->b_vp); /* put on clean list */ 680 ++tbp->b_vp->v_numoutput; 681 splx(s); 682 TAILQ_INSERT_TAIL(&bp->b_cluster.cluster_head, 683 tbp, b_cluster.cluster_entry); 684 } 685 pmap_qenter(trunc_page((vm_offset_t) bp->b_data), 686 (vm_page_t *) bp->b_pages, bp->b_npages); 687 totalwritten += bp->b_bufsize; 688 bp->b_dirtyoff = 0; 689 bp->b_dirtyend = bp->b_bufsize; 690 bawrite(bp); 691 692 len -= i; 693 } 694 return totalwritten; 695 } 696 697 #ifdef notyet_block_reallocation_enabled 698 /* 699 * Collect together all the buffers in a cluster. 700 * Plus add one additional buffer. 701 */ 702 static struct cluster_save * 703 cluster_collectbufs(vp, last_bp) 704 struct vnode *vp; 705 struct buf *last_bp; 706 { 707 struct cluster_save *buflist; 708 daddr_t lbn; 709 int i, len; 710 711 len = vp->v_lastw - vp->v_cstart + 1; 712 buflist = malloc(sizeof(struct buf *) * (len + 1) + sizeof(*buflist), 713 M_SEGMENT, M_WAITOK); 714 buflist->bs_nchildren = 0; 715 buflist->bs_children = (struct buf **) (buflist + 1); 716 for (lbn = vp->v_cstart, i = 0; i < len; lbn++, i++) 717 (void) bread(vp, lbn, last_bp->b_bcount, NOCRED, 718 &buflist->bs_children[i]); 719 buflist->bs_children[i] = last_bp; 720 buflist->bs_nchildren = i + 1; 721 return (buflist); 722 } 723 #endif /* notyet_block_reallocation_enabled */ 724