1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Rick Macklem at The University of Guelph. 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 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95 33 */ 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/bio.h> 41 #include <sys/buf.h> 42 #include <sys/kernel.h> 43 #include <sys/mount.h> 44 #include <sys/rwlock.h> 45 #include <sys/vmmeter.h> 46 #include <sys/vnode.h> 47 48 #include <vm/vm.h> 49 #include <vm/vm_param.h> 50 #include <vm/vm_extern.h> 51 #include <vm/vm_page.h> 52 #include <vm/vm_object.h> 53 #include <vm/vm_pager.h> 54 #include <vm/vnode_pager.h> 55 56 #include <fs/nfs/nfsport.h> 57 #include <fs/nfsclient/nfsmount.h> 58 #include <fs/nfsclient/nfs.h> 59 #include <fs/nfsclient/nfsnode.h> 60 #include <fs/nfsclient/nfs_kdtrace.h> 61 62 extern int newnfs_directio_allow_mmap; 63 extern struct nfsstats newnfsstats; 64 extern struct mtx ncl_iod_mutex; 65 extern int ncl_numasync; 66 extern enum nfsiod_state ncl_iodwant[NFS_MAXASYNCDAEMON]; 67 extern struct nfsmount *ncl_iodmount[NFS_MAXASYNCDAEMON]; 68 extern int newnfs_directio_enable; 69 extern int nfs_keep_dirty_on_error; 70 71 int ncl_pbuf_freecnt = -1; /* start out unlimited */ 72 73 static struct buf *nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, 74 struct thread *td); 75 static int nfs_directio_write(struct vnode *vp, struct uio *uiop, 76 struct ucred *cred, int ioflag); 77 78 /* 79 * Vnode op for VM getpages. 80 */ 81 int 82 ncl_getpages(struct vop_getpages_args *ap) 83 { 84 int i, error, nextoff, size, toff, count, npages; 85 struct uio uio; 86 struct iovec iov; 87 vm_offset_t kva; 88 struct buf *bp; 89 struct vnode *vp; 90 struct thread *td; 91 struct ucred *cred; 92 struct nfsmount *nmp; 93 vm_object_t object; 94 vm_page_t *pages; 95 struct nfsnode *np; 96 97 vp = ap->a_vp; 98 np = VTONFS(vp); 99 td = curthread; /* XXX */ 100 cred = curthread->td_ucred; /* XXX */ 101 nmp = VFSTONFS(vp->v_mount); 102 pages = ap->a_m; 103 count = ap->a_count; 104 105 if ((object = vp->v_object) == NULL) { 106 ncl_printf("nfs_getpages: called with non-merged cache vnode??\n"); 107 return (VM_PAGER_ERROR); 108 } 109 110 if (newnfs_directio_enable && !newnfs_directio_allow_mmap) { 111 mtx_lock(&np->n_mtx); 112 if ((np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 113 mtx_unlock(&np->n_mtx); 114 ncl_printf("nfs_getpages: called on non-cacheable vnode??\n"); 115 return (VM_PAGER_ERROR); 116 } else 117 mtx_unlock(&np->n_mtx); 118 } 119 120 mtx_lock(&nmp->nm_mtx); 121 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 122 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 123 mtx_unlock(&nmp->nm_mtx); 124 /* We'll never get here for v4, because we always have fsinfo */ 125 (void)ncl_fsinfo(nmp, vp, cred, td); 126 } else 127 mtx_unlock(&nmp->nm_mtx); 128 129 npages = btoc(count); 130 131 /* 132 * If the requested page is partially valid, just return it and 133 * allow the pager to zero-out the blanks. Partially valid pages 134 * can only occur at the file EOF. 135 */ 136 if (pages[ap->a_reqpage]->valid != 0) { 137 vm_pager_free_nonreq(object, pages, ap->a_reqpage, npages, 138 FALSE); 139 return (VM_PAGER_OK); 140 } 141 142 /* 143 * We use only the kva address for the buffer, but this is extremely 144 * convienient and fast. 145 */ 146 bp = getpbuf(&ncl_pbuf_freecnt); 147 148 kva = (vm_offset_t) bp->b_data; 149 pmap_qenter(kva, pages, npages); 150 PCPU_INC(cnt.v_vnodein); 151 PCPU_ADD(cnt.v_vnodepgsin, npages); 152 153 iov.iov_base = (caddr_t) kva; 154 iov.iov_len = count; 155 uio.uio_iov = &iov; 156 uio.uio_iovcnt = 1; 157 uio.uio_offset = IDX_TO_OFF(pages[0]->pindex); 158 uio.uio_resid = count; 159 uio.uio_segflg = UIO_SYSSPACE; 160 uio.uio_rw = UIO_READ; 161 uio.uio_td = td; 162 163 error = ncl_readrpc(vp, &uio, cred); 164 pmap_qremove(kva, npages); 165 166 relpbuf(bp, &ncl_pbuf_freecnt); 167 168 if (error && (uio.uio_resid == count)) { 169 ncl_printf("nfs_getpages: error %d\n", error); 170 vm_pager_free_nonreq(object, pages, ap->a_reqpage, npages, 171 FALSE); 172 return (VM_PAGER_ERROR); 173 } 174 175 /* 176 * Calculate the number of bytes read and validate only that number 177 * of bytes. Note that due to pending writes, size may be 0. This 178 * does not mean that the remaining data is invalid! 179 */ 180 181 size = count - uio.uio_resid; 182 VM_OBJECT_WLOCK(object); 183 for (i = 0, toff = 0; i < npages; i++, toff = nextoff) { 184 vm_page_t m; 185 nextoff = toff + PAGE_SIZE; 186 m = pages[i]; 187 188 if (nextoff <= size) { 189 /* 190 * Read operation filled an entire page 191 */ 192 m->valid = VM_PAGE_BITS_ALL; 193 KASSERT(m->dirty == 0, 194 ("nfs_getpages: page %p is dirty", m)); 195 } else if (size > toff) { 196 /* 197 * Read operation filled a partial page. 198 */ 199 m->valid = 0; 200 vm_page_set_valid_range(m, 0, size - toff); 201 KASSERT(m->dirty == 0, 202 ("nfs_getpages: page %p is dirty", m)); 203 } else { 204 /* 205 * Read operation was short. If no error 206 * occured we may have hit a zero-fill 207 * section. We leave valid set to 0, and page 208 * is freed by vm_page_readahead_finish() if 209 * its index is not equal to requested, or 210 * page is zeroed and set valid by 211 * vm_pager_get_pages() for requested page. 212 */ 213 ; 214 } 215 if (i != ap->a_reqpage) 216 vm_page_readahead_finish(m); 217 } 218 VM_OBJECT_WUNLOCK(object); 219 return (0); 220 } 221 222 /* 223 * Vnode op for VM putpages. 224 */ 225 int 226 ncl_putpages(struct vop_putpages_args *ap) 227 { 228 struct uio uio; 229 struct iovec iov; 230 vm_offset_t kva; 231 struct buf *bp; 232 int iomode, must_commit, i, error, npages, count; 233 off_t offset; 234 int *rtvals; 235 struct vnode *vp; 236 struct thread *td; 237 struct ucred *cred; 238 struct nfsmount *nmp; 239 struct nfsnode *np; 240 vm_page_t *pages; 241 242 vp = ap->a_vp; 243 np = VTONFS(vp); 244 td = curthread; /* XXX */ 245 /* Set the cred to n_writecred for the write rpcs. */ 246 if (np->n_writecred != NULL) 247 cred = crhold(np->n_writecred); 248 else 249 cred = crhold(curthread->td_ucred); /* XXX */ 250 nmp = VFSTONFS(vp->v_mount); 251 pages = ap->a_m; 252 count = ap->a_count; 253 rtvals = ap->a_rtvals; 254 npages = btoc(count); 255 offset = IDX_TO_OFF(pages[0]->pindex); 256 257 mtx_lock(&nmp->nm_mtx); 258 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 259 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 260 mtx_unlock(&nmp->nm_mtx); 261 (void)ncl_fsinfo(nmp, vp, cred, td); 262 } else 263 mtx_unlock(&nmp->nm_mtx); 264 265 mtx_lock(&np->n_mtx); 266 if (newnfs_directio_enable && !newnfs_directio_allow_mmap && 267 (np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 268 mtx_unlock(&np->n_mtx); 269 ncl_printf("ncl_putpages: called on noncache-able vnode??\n"); 270 mtx_lock(&np->n_mtx); 271 } 272 273 for (i = 0; i < npages; i++) 274 rtvals[i] = VM_PAGER_ERROR; 275 276 /* 277 * When putting pages, do not extend file past EOF. 278 */ 279 if (offset + count > np->n_size) { 280 count = np->n_size - offset; 281 if (count < 0) 282 count = 0; 283 } 284 mtx_unlock(&np->n_mtx); 285 286 /* 287 * We use only the kva address for the buffer, but this is extremely 288 * convienient and fast. 289 */ 290 bp = getpbuf(&ncl_pbuf_freecnt); 291 292 kva = (vm_offset_t) bp->b_data; 293 pmap_qenter(kva, pages, npages); 294 PCPU_INC(cnt.v_vnodeout); 295 PCPU_ADD(cnt.v_vnodepgsout, count); 296 297 iov.iov_base = (caddr_t) kva; 298 iov.iov_len = count; 299 uio.uio_iov = &iov; 300 uio.uio_iovcnt = 1; 301 uio.uio_offset = offset; 302 uio.uio_resid = count; 303 uio.uio_segflg = UIO_SYSSPACE; 304 uio.uio_rw = UIO_WRITE; 305 uio.uio_td = td; 306 307 if ((ap->a_sync & VM_PAGER_PUT_SYNC) == 0) 308 iomode = NFSWRITE_UNSTABLE; 309 else 310 iomode = NFSWRITE_FILESYNC; 311 312 error = ncl_writerpc(vp, &uio, cred, &iomode, &must_commit, 0); 313 crfree(cred); 314 315 pmap_qremove(kva, npages); 316 relpbuf(bp, &ncl_pbuf_freecnt); 317 318 if (error == 0 || !nfs_keep_dirty_on_error) { 319 vnode_pager_undirty_pages(pages, rtvals, count - uio.uio_resid); 320 if (must_commit) 321 ncl_clearcommit(vp->v_mount); 322 } 323 return rtvals[0]; 324 } 325 326 /* 327 * For nfs, cache consistency can only be maintained approximately. 328 * Although RFC1094 does not specify the criteria, the following is 329 * believed to be compatible with the reference port. 330 * For nfs: 331 * If the file's modify time on the server has changed since the 332 * last read rpc or you have written to the file, 333 * you may have lost data cache consistency with the 334 * server, so flush all of the file's data out of the cache. 335 * Then force a getattr rpc to ensure that you have up to date 336 * attributes. 337 * NB: This implies that cache data can be read when up to 338 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 339 * attributes this could be forced by setting n_attrstamp to 0 before 340 * the VOP_GETATTR() call. 341 */ 342 static inline int 343 nfs_bioread_check_cons(struct vnode *vp, struct thread *td, struct ucred *cred) 344 { 345 int error = 0; 346 struct vattr vattr; 347 struct nfsnode *np = VTONFS(vp); 348 int old_lock; 349 350 /* 351 * Grab the exclusive lock before checking whether the cache is 352 * consistent. 353 * XXX - We can make this cheaper later (by acquiring cheaper locks). 354 * But for now, this suffices. 355 */ 356 old_lock = ncl_upgrade_vnlock(vp); 357 if (vp->v_iflag & VI_DOOMED) { 358 ncl_downgrade_vnlock(vp, old_lock); 359 return (EBADF); 360 } 361 362 mtx_lock(&np->n_mtx); 363 if (np->n_flag & NMODIFIED) { 364 mtx_unlock(&np->n_mtx); 365 if (vp->v_type != VREG) { 366 if (vp->v_type != VDIR) 367 panic("nfs: bioread, not dir"); 368 ncl_invaldir(vp); 369 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 370 if (error) 371 goto out; 372 } 373 np->n_attrstamp = 0; 374 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 375 error = VOP_GETATTR(vp, &vattr, cred); 376 if (error) 377 goto out; 378 mtx_lock(&np->n_mtx); 379 np->n_mtime = vattr.va_mtime; 380 mtx_unlock(&np->n_mtx); 381 } else { 382 mtx_unlock(&np->n_mtx); 383 error = VOP_GETATTR(vp, &vattr, cred); 384 if (error) 385 return (error); 386 mtx_lock(&np->n_mtx); 387 if ((np->n_flag & NSIZECHANGED) 388 || (NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime))) { 389 mtx_unlock(&np->n_mtx); 390 if (vp->v_type == VDIR) 391 ncl_invaldir(vp); 392 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 393 if (error) 394 goto out; 395 mtx_lock(&np->n_mtx); 396 np->n_mtime = vattr.va_mtime; 397 np->n_flag &= ~NSIZECHANGED; 398 } 399 mtx_unlock(&np->n_mtx); 400 } 401 out: 402 ncl_downgrade_vnlock(vp, old_lock); 403 return error; 404 } 405 406 /* 407 * Vnode op for read using bio 408 */ 409 int 410 ncl_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred) 411 { 412 struct nfsnode *np = VTONFS(vp); 413 int biosize, i; 414 struct buf *bp, *rabp; 415 struct thread *td; 416 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 417 daddr_t lbn, rabn; 418 int bcount; 419 int seqcount; 420 int nra, error = 0, n = 0, on = 0; 421 off_t tmp_off; 422 423 KASSERT(uio->uio_rw == UIO_READ, ("ncl_read mode")); 424 if (uio->uio_resid == 0) 425 return (0); 426 if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */ 427 return (EINVAL); 428 td = uio->uio_td; 429 430 mtx_lock(&nmp->nm_mtx); 431 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 432 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 433 mtx_unlock(&nmp->nm_mtx); 434 (void)ncl_fsinfo(nmp, vp, cred, td); 435 mtx_lock(&nmp->nm_mtx); 436 } 437 if (nmp->nm_rsize == 0 || nmp->nm_readdirsize == 0) 438 (void) newnfs_iosize(nmp); 439 440 tmp_off = uio->uio_offset + uio->uio_resid; 441 if (vp->v_type != VDIR && 442 (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset)) { 443 mtx_unlock(&nmp->nm_mtx); 444 return (EFBIG); 445 } 446 mtx_unlock(&nmp->nm_mtx); 447 448 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && (vp->v_type == VREG)) 449 /* No caching/ no readaheads. Just read data into the user buffer */ 450 return ncl_readrpc(vp, uio, cred); 451 452 biosize = vp->v_bufobj.bo_bsize; 453 seqcount = (int)((off_t)(ioflag >> IO_SEQSHIFT) * biosize / BKVASIZE); 454 455 error = nfs_bioread_check_cons(vp, td, cred); 456 if (error) 457 return error; 458 459 do { 460 u_quad_t nsize; 461 462 mtx_lock(&np->n_mtx); 463 nsize = np->n_size; 464 mtx_unlock(&np->n_mtx); 465 466 switch (vp->v_type) { 467 case VREG: 468 NFSINCRGLOBAL(newnfsstats.biocache_reads); 469 lbn = uio->uio_offset / biosize; 470 on = uio->uio_offset - (lbn * biosize); 471 472 /* 473 * Start the read ahead(s), as required. 474 */ 475 if (nmp->nm_readahead > 0) { 476 for (nra = 0; nra < nmp->nm_readahead && nra < seqcount && 477 (off_t)(lbn + 1 + nra) * biosize < nsize; nra++) { 478 rabn = lbn + 1 + nra; 479 if (incore(&vp->v_bufobj, rabn) == NULL) { 480 rabp = nfs_getcacheblk(vp, rabn, biosize, td); 481 if (!rabp) { 482 error = newnfs_sigintr(nmp, td); 483 return (error ? error : EINTR); 484 } 485 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 486 rabp->b_flags |= B_ASYNC; 487 rabp->b_iocmd = BIO_READ; 488 vfs_busy_pages(rabp, 0); 489 if (ncl_asyncio(nmp, rabp, cred, td)) { 490 rabp->b_flags |= B_INVAL; 491 rabp->b_ioflags |= BIO_ERROR; 492 vfs_unbusy_pages(rabp); 493 brelse(rabp); 494 break; 495 } 496 } else { 497 brelse(rabp); 498 } 499 } 500 } 501 } 502 503 /* Note that bcount is *not* DEV_BSIZE aligned. */ 504 bcount = biosize; 505 if ((off_t)lbn * biosize >= nsize) { 506 bcount = 0; 507 } else if ((off_t)(lbn + 1) * biosize > nsize) { 508 bcount = nsize - (off_t)lbn * biosize; 509 } 510 bp = nfs_getcacheblk(vp, lbn, bcount, td); 511 512 if (!bp) { 513 error = newnfs_sigintr(nmp, td); 514 return (error ? error : EINTR); 515 } 516 517 /* 518 * If B_CACHE is not set, we must issue the read. If this 519 * fails, we return an error. 520 */ 521 522 if ((bp->b_flags & B_CACHE) == 0) { 523 bp->b_iocmd = BIO_READ; 524 vfs_busy_pages(bp, 0); 525 error = ncl_doio(vp, bp, cred, td, 0); 526 if (error) { 527 brelse(bp); 528 return (error); 529 } 530 } 531 532 /* 533 * on is the offset into the current bp. Figure out how many 534 * bytes we can copy out of the bp. Note that bcount is 535 * NOT DEV_BSIZE aligned. 536 * 537 * Then figure out how many bytes we can copy into the uio. 538 */ 539 540 n = 0; 541 if (on < bcount) 542 n = MIN((unsigned)(bcount - on), uio->uio_resid); 543 break; 544 case VLNK: 545 NFSINCRGLOBAL(newnfsstats.biocache_readlinks); 546 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, td); 547 if (!bp) { 548 error = newnfs_sigintr(nmp, td); 549 return (error ? error : EINTR); 550 } 551 if ((bp->b_flags & B_CACHE) == 0) { 552 bp->b_iocmd = BIO_READ; 553 vfs_busy_pages(bp, 0); 554 error = ncl_doio(vp, bp, cred, td, 0); 555 if (error) { 556 bp->b_ioflags |= BIO_ERROR; 557 brelse(bp); 558 return (error); 559 } 560 } 561 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 562 on = 0; 563 break; 564 case VDIR: 565 NFSINCRGLOBAL(newnfsstats.biocache_readdirs); 566 if (np->n_direofoffset 567 && uio->uio_offset >= np->n_direofoffset) { 568 return (0); 569 } 570 lbn = (uoff_t)uio->uio_offset / NFS_DIRBLKSIZ; 571 on = uio->uio_offset & (NFS_DIRBLKSIZ - 1); 572 bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, td); 573 if (!bp) { 574 error = newnfs_sigintr(nmp, td); 575 return (error ? error : EINTR); 576 } 577 if ((bp->b_flags & B_CACHE) == 0) { 578 bp->b_iocmd = BIO_READ; 579 vfs_busy_pages(bp, 0); 580 error = ncl_doio(vp, bp, cred, td, 0); 581 if (error) { 582 brelse(bp); 583 } 584 while (error == NFSERR_BAD_COOKIE) { 585 ncl_invaldir(vp); 586 error = ncl_vinvalbuf(vp, 0, td, 1); 587 /* 588 * Yuck! The directory has been modified on the 589 * server. The only way to get the block is by 590 * reading from the beginning to get all the 591 * offset cookies. 592 * 593 * Leave the last bp intact unless there is an error. 594 * Loop back up to the while if the error is another 595 * NFSERR_BAD_COOKIE (double yuch!). 596 */ 597 for (i = 0; i <= lbn && !error; i++) { 598 if (np->n_direofoffset 599 && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset) 600 return (0); 601 bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, td); 602 if (!bp) { 603 error = newnfs_sigintr(nmp, td); 604 return (error ? error : EINTR); 605 } 606 if ((bp->b_flags & B_CACHE) == 0) { 607 bp->b_iocmd = BIO_READ; 608 vfs_busy_pages(bp, 0); 609 error = ncl_doio(vp, bp, cred, td, 0); 610 /* 611 * no error + B_INVAL == directory EOF, 612 * use the block. 613 */ 614 if (error == 0 && (bp->b_flags & B_INVAL)) 615 break; 616 } 617 /* 618 * An error will throw away the block and the 619 * for loop will break out. If no error and this 620 * is not the block we want, we throw away the 621 * block and go for the next one via the for loop. 622 */ 623 if (error || i < lbn) 624 brelse(bp); 625 } 626 } 627 /* 628 * The above while is repeated if we hit another cookie 629 * error. If we hit an error and it wasn't a cookie error, 630 * we give up. 631 */ 632 if (error) 633 return (error); 634 } 635 636 /* 637 * If not eof and read aheads are enabled, start one. 638 * (You need the current block first, so that you have the 639 * directory offset cookie of the next block.) 640 */ 641 if (nmp->nm_readahead > 0 && 642 (bp->b_flags & B_INVAL) == 0 && 643 (np->n_direofoffset == 0 || 644 (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) && 645 incore(&vp->v_bufobj, lbn + 1) == NULL) { 646 rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td); 647 if (rabp) { 648 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 649 rabp->b_flags |= B_ASYNC; 650 rabp->b_iocmd = BIO_READ; 651 vfs_busy_pages(rabp, 0); 652 if (ncl_asyncio(nmp, rabp, cred, td)) { 653 rabp->b_flags |= B_INVAL; 654 rabp->b_ioflags |= BIO_ERROR; 655 vfs_unbusy_pages(rabp); 656 brelse(rabp); 657 } 658 } else { 659 brelse(rabp); 660 } 661 } 662 } 663 /* 664 * Unlike VREG files, whos buffer size ( bp->b_bcount ) is 665 * chopped for the EOF condition, we cannot tell how large 666 * NFS directories are going to be until we hit EOF. So 667 * an NFS directory buffer is *not* chopped to its EOF. Now, 668 * it just so happens that b_resid will effectively chop it 669 * to EOF. *BUT* this information is lost if the buffer goes 670 * away and is reconstituted into a B_CACHE state ( due to 671 * being VMIO ) later. So we keep track of the directory eof 672 * in np->n_direofoffset and chop it off as an extra step 673 * right here. 674 */ 675 n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on); 676 if (np->n_direofoffset && n > np->n_direofoffset - uio->uio_offset) 677 n = np->n_direofoffset - uio->uio_offset; 678 break; 679 default: 680 ncl_printf(" ncl_bioread: type %x unexpected\n", vp->v_type); 681 bp = NULL; 682 break; 683 }; 684 685 if (n > 0) { 686 error = vn_io_fault_uiomove(bp->b_data + on, (int)n, uio); 687 } 688 if (vp->v_type == VLNK) 689 n = 0; 690 if (bp != NULL) 691 brelse(bp); 692 } while (error == 0 && uio->uio_resid > 0 && n > 0); 693 return (error); 694 } 695 696 /* 697 * The NFS write path cannot handle iovecs with len > 1. So we need to 698 * break up iovecs accordingly (restricting them to wsize). 699 * For the SYNC case, we can do this with 1 copy (user buffer -> mbuf). 700 * For the ASYNC case, 2 copies are needed. The first a copy from the 701 * user buffer to a staging buffer and then a second copy from the staging 702 * buffer to mbufs. This can be optimized by copying from the user buffer 703 * directly into mbufs and passing the chain down, but that requires a 704 * fair amount of re-working of the relevant codepaths (and can be done 705 * later). 706 */ 707 static int 708 nfs_directio_write(vp, uiop, cred, ioflag) 709 struct vnode *vp; 710 struct uio *uiop; 711 struct ucred *cred; 712 int ioflag; 713 { 714 int error; 715 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 716 struct thread *td = uiop->uio_td; 717 int size; 718 int wsize; 719 720 mtx_lock(&nmp->nm_mtx); 721 wsize = nmp->nm_wsize; 722 mtx_unlock(&nmp->nm_mtx); 723 if (ioflag & IO_SYNC) { 724 int iomode, must_commit; 725 struct uio uio; 726 struct iovec iov; 727 do_sync: 728 while (uiop->uio_resid > 0) { 729 size = MIN(uiop->uio_resid, wsize); 730 size = MIN(uiop->uio_iov->iov_len, size); 731 iov.iov_base = uiop->uio_iov->iov_base; 732 iov.iov_len = size; 733 uio.uio_iov = &iov; 734 uio.uio_iovcnt = 1; 735 uio.uio_offset = uiop->uio_offset; 736 uio.uio_resid = size; 737 uio.uio_segflg = UIO_USERSPACE; 738 uio.uio_rw = UIO_WRITE; 739 uio.uio_td = td; 740 iomode = NFSWRITE_FILESYNC; 741 error = ncl_writerpc(vp, &uio, cred, &iomode, 742 &must_commit, 0); 743 KASSERT((must_commit == 0), 744 ("ncl_directio_write: Did not commit write")); 745 if (error) 746 return (error); 747 uiop->uio_offset += size; 748 uiop->uio_resid -= size; 749 if (uiop->uio_iov->iov_len <= size) { 750 uiop->uio_iovcnt--; 751 uiop->uio_iov++; 752 } else { 753 uiop->uio_iov->iov_base = 754 (char *)uiop->uio_iov->iov_base + size; 755 uiop->uio_iov->iov_len -= size; 756 } 757 } 758 } else { 759 struct uio *t_uio; 760 struct iovec *t_iov; 761 struct buf *bp; 762 763 /* 764 * Break up the write into blocksize chunks and hand these 765 * over to nfsiod's for write back. 766 * Unfortunately, this incurs a copy of the data. Since 767 * the user could modify the buffer before the write is 768 * initiated. 769 * 770 * The obvious optimization here is that one of the 2 copies 771 * in the async write path can be eliminated by copying the 772 * data here directly into mbufs and passing the mbuf chain 773 * down. But that will require a fair amount of re-working 774 * of the code and can be done if there's enough interest 775 * in NFS directio access. 776 */ 777 while (uiop->uio_resid > 0) { 778 size = MIN(uiop->uio_resid, wsize); 779 size = MIN(uiop->uio_iov->iov_len, size); 780 bp = getpbuf(&ncl_pbuf_freecnt); 781 t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK); 782 t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK); 783 t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK); 784 t_iov->iov_len = size; 785 t_uio->uio_iov = t_iov; 786 t_uio->uio_iovcnt = 1; 787 t_uio->uio_offset = uiop->uio_offset; 788 t_uio->uio_resid = size; 789 t_uio->uio_segflg = UIO_SYSSPACE; 790 t_uio->uio_rw = UIO_WRITE; 791 t_uio->uio_td = td; 792 KASSERT(uiop->uio_segflg == UIO_USERSPACE || 793 uiop->uio_segflg == UIO_SYSSPACE, 794 ("nfs_directio_write: Bad uio_segflg")); 795 if (uiop->uio_segflg == UIO_USERSPACE) { 796 error = copyin(uiop->uio_iov->iov_base, 797 t_iov->iov_base, size); 798 if (error != 0) 799 goto err_free; 800 } else 801 /* 802 * UIO_SYSSPACE may never happen, but handle 803 * it just in case it does. 804 */ 805 bcopy(uiop->uio_iov->iov_base, t_iov->iov_base, 806 size); 807 bp->b_flags |= B_DIRECT; 808 bp->b_iocmd = BIO_WRITE; 809 if (cred != NOCRED) { 810 crhold(cred); 811 bp->b_wcred = cred; 812 } else 813 bp->b_wcred = NOCRED; 814 bp->b_caller1 = (void *)t_uio; 815 bp->b_vp = vp; 816 error = ncl_asyncio(nmp, bp, NOCRED, td); 817 err_free: 818 if (error) { 819 free(t_iov->iov_base, M_NFSDIRECTIO); 820 free(t_iov, M_NFSDIRECTIO); 821 free(t_uio, M_NFSDIRECTIO); 822 bp->b_vp = NULL; 823 relpbuf(bp, &ncl_pbuf_freecnt); 824 if (error == EINTR) 825 return (error); 826 goto do_sync; 827 } 828 uiop->uio_offset += size; 829 uiop->uio_resid -= size; 830 if (uiop->uio_iov->iov_len <= size) { 831 uiop->uio_iovcnt--; 832 uiop->uio_iov++; 833 } else { 834 uiop->uio_iov->iov_base = 835 (char *)uiop->uio_iov->iov_base + size; 836 uiop->uio_iov->iov_len -= size; 837 } 838 } 839 } 840 return (0); 841 } 842 843 /* 844 * Vnode op for write using bio 845 */ 846 int 847 ncl_write(struct vop_write_args *ap) 848 { 849 int biosize; 850 struct uio *uio = ap->a_uio; 851 struct thread *td = uio->uio_td; 852 struct vnode *vp = ap->a_vp; 853 struct nfsnode *np = VTONFS(vp); 854 struct ucred *cred = ap->a_cred; 855 int ioflag = ap->a_ioflag; 856 struct buf *bp; 857 struct vattr vattr; 858 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 859 daddr_t lbn; 860 int bcount, noncontig_write, obcount; 861 int bp_cached, n, on, error = 0, error1, wouldcommit; 862 size_t orig_resid, local_resid; 863 off_t orig_size, tmp_off; 864 865 KASSERT(uio->uio_rw == UIO_WRITE, ("ncl_write mode")); 866 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 867 ("ncl_write proc")); 868 if (vp->v_type != VREG) 869 return (EIO); 870 mtx_lock(&np->n_mtx); 871 if (np->n_flag & NWRITEERR) { 872 np->n_flag &= ~NWRITEERR; 873 mtx_unlock(&np->n_mtx); 874 return (np->n_error); 875 } else 876 mtx_unlock(&np->n_mtx); 877 mtx_lock(&nmp->nm_mtx); 878 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 879 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 880 mtx_unlock(&nmp->nm_mtx); 881 (void)ncl_fsinfo(nmp, vp, cred, td); 882 mtx_lock(&nmp->nm_mtx); 883 } 884 if (nmp->nm_wsize == 0) 885 (void) newnfs_iosize(nmp); 886 mtx_unlock(&nmp->nm_mtx); 887 888 /* 889 * Synchronously flush pending buffers if we are in synchronous 890 * mode or if we are appending. 891 */ 892 if (ioflag & (IO_APPEND | IO_SYNC)) { 893 mtx_lock(&np->n_mtx); 894 if (np->n_flag & NMODIFIED) { 895 mtx_unlock(&np->n_mtx); 896 #ifdef notyet /* Needs matching nonblock semantics elsewhere, too. */ 897 /* 898 * Require non-blocking, synchronous writes to 899 * dirty files to inform the program it needs 900 * to fsync(2) explicitly. 901 */ 902 if (ioflag & IO_NDELAY) 903 return (EAGAIN); 904 #endif 905 np->n_attrstamp = 0; 906 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 907 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 908 if (error) 909 return (error); 910 } else 911 mtx_unlock(&np->n_mtx); 912 } 913 914 orig_resid = uio->uio_resid; 915 mtx_lock(&np->n_mtx); 916 orig_size = np->n_size; 917 mtx_unlock(&np->n_mtx); 918 919 /* 920 * If IO_APPEND then load uio_offset. We restart here if we cannot 921 * get the append lock. 922 */ 923 if (ioflag & IO_APPEND) { 924 np->n_attrstamp = 0; 925 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 926 error = VOP_GETATTR(vp, &vattr, cred); 927 if (error) 928 return (error); 929 mtx_lock(&np->n_mtx); 930 uio->uio_offset = np->n_size; 931 mtx_unlock(&np->n_mtx); 932 } 933 934 if (uio->uio_offset < 0) 935 return (EINVAL); 936 tmp_off = uio->uio_offset + uio->uio_resid; 937 if (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset) 938 return (EFBIG); 939 if (uio->uio_resid == 0) 940 return (0); 941 942 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && vp->v_type == VREG) 943 return nfs_directio_write(vp, uio, cred, ioflag); 944 945 /* 946 * Maybe this should be above the vnode op call, but so long as 947 * file servers have no limits, i don't think it matters 948 */ 949 if (vn_rlimit_fsize(vp, uio, td)) 950 return (EFBIG); 951 952 biosize = vp->v_bufobj.bo_bsize; 953 /* 954 * Find all of this file's B_NEEDCOMMIT buffers. If our writes 955 * would exceed the local maximum per-file write commit size when 956 * combined with those, we must decide whether to flush, 957 * go synchronous, or return error. We don't bother checking 958 * IO_UNIT -- we just make all writes atomic anyway, as there's 959 * no point optimizing for something that really won't ever happen. 960 */ 961 wouldcommit = 0; 962 if (!(ioflag & IO_SYNC)) { 963 int nflag; 964 965 mtx_lock(&np->n_mtx); 966 nflag = np->n_flag; 967 mtx_unlock(&np->n_mtx); 968 if (nflag & NMODIFIED) { 969 BO_LOCK(&vp->v_bufobj); 970 if (vp->v_bufobj.bo_dirty.bv_cnt != 0) { 971 TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd, 972 b_bobufs) { 973 if (bp->b_flags & B_NEEDCOMMIT) 974 wouldcommit += bp->b_bcount; 975 } 976 } 977 BO_UNLOCK(&vp->v_bufobj); 978 } 979 } 980 981 do { 982 if (!(ioflag & IO_SYNC)) { 983 wouldcommit += biosize; 984 if (wouldcommit > nmp->nm_wcommitsize) { 985 np->n_attrstamp = 0; 986 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 987 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 988 if (error) 989 return (error); 990 wouldcommit = biosize; 991 } 992 } 993 994 NFSINCRGLOBAL(newnfsstats.biocache_writes); 995 lbn = uio->uio_offset / biosize; 996 on = uio->uio_offset - (lbn * biosize); 997 n = MIN((unsigned)(biosize - on), uio->uio_resid); 998 again: 999 /* 1000 * Handle direct append and file extension cases, calculate 1001 * unaligned buffer size. 1002 */ 1003 mtx_lock(&np->n_mtx); 1004 if ((np->n_flag & NHASBEENLOCKED) == 0 && 1005 (nmp->nm_flag & NFSMNT_NONCONTIGWR) != 0) 1006 noncontig_write = 1; 1007 else 1008 noncontig_write = 0; 1009 if ((uio->uio_offset == np->n_size || 1010 (noncontig_write != 0 && 1011 lbn == (np->n_size / biosize) && 1012 uio->uio_offset + n > np->n_size)) && n) { 1013 mtx_unlock(&np->n_mtx); 1014 /* 1015 * Get the buffer (in its pre-append state to maintain 1016 * B_CACHE if it was previously set). Resize the 1017 * nfsnode after we have locked the buffer to prevent 1018 * readers from reading garbage. 1019 */ 1020 obcount = np->n_size - (lbn * biosize); 1021 bp = nfs_getcacheblk(vp, lbn, obcount, td); 1022 1023 if (bp != NULL) { 1024 long save; 1025 1026 mtx_lock(&np->n_mtx); 1027 np->n_size = uio->uio_offset + n; 1028 np->n_flag |= NMODIFIED; 1029 vnode_pager_setsize(vp, np->n_size); 1030 mtx_unlock(&np->n_mtx); 1031 1032 save = bp->b_flags & B_CACHE; 1033 bcount = on + n; 1034 allocbuf(bp, bcount); 1035 bp->b_flags |= save; 1036 if (noncontig_write != 0 && on > obcount) 1037 vfs_bio_bzero_buf(bp, obcount, on - 1038 obcount); 1039 } 1040 } else { 1041 /* 1042 * Obtain the locked cache block first, and then 1043 * adjust the file's size as appropriate. 1044 */ 1045 bcount = on + n; 1046 if ((off_t)lbn * biosize + bcount < np->n_size) { 1047 if ((off_t)(lbn + 1) * biosize < np->n_size) 1048 bcount = biosize; 1049 else 1050 bcount = np->n_size - (off_t)lbn * biosize; 1051 } 1052 mtx_unlock(&np->n_mtx); 1053 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1054 mtx_lock(&np->n_mtx); 1055 if (uio->uio_offset + n > np->n_size) { 1056 np->n_size = uio->uio_offset + n; 1057 np->n_flag |= NMODIFIED; 1058 vnode_pager_setsize(vp, np->n_size); 1059 } 1060 mtx_unlock(&np->n_mtx); 1061 } 1062 1063 if (!bp) { 1064 error = newnfs_sigintr(nmp, td); 1065 if (!error) 1066 error = EINTR; 1067 break; 1068 } 1069 1070 /* 1071 * Issue a READ if B_CACHE is not set. In special-append 1072 * mode, B_CACHE is based on the buffer prior to the write 1073 * op and is typically set, avoiding the read. If a read 1074 * is required in special append mode, the server will 1075 * probably send us a short-read since we extended the file 1076 * on our end, resulting in b_resid == 0 and, thusly, 1077 * B_CACHE getting set. 1078 * 1079 * We can also avoid issuing the read if the write covers 1080 * the entire buffer. We have to make sure the buffer state 1081 * is reasonable in this case since we will not be initiating 1082 * I/O. See the comments in kern/vfs_bio.c's getblk() for 1083 * more information. 1084 * 1085 * B_CACHE may also be set due to the buffer being cached 1086 * normally. 1087 */ 1088 1089 bp_cached = 1; 1090 if (on == 0 && n == bcount) { 1091 if ((bp->b_flags & B_CACHE) == 0) 1092 bp_cached = 0; 1093 bp->b_flags |= B_CACHE; 1094 bp->b_flags &= ~B_INVAL; 1095 bp->b_ioflags &= ~BIO_ERROR; 1096 } 1097 1098 if ((bp->b_flags & B_CACHE) == 0) { 1099 bp->b_iocmd = BIO_READ; 1100 vfs_busy_pages(bp, 0); 1101 error = ncl_doio(vp, bp, cred, td, 0); 1102 if (error) { 1103 brelse(bp); 1104 break; 1105 } 1106 } 1107 if (bp->b_wcred == NOCRED) 1108 bp->b_wcred = crhold(cred); 1109 mtx_lock(&np->n_mtx); 1110 np->n_flag |= NMODIFIED; 1111 mtx_unlock(&np->n_mtx); 1112 1113 /* 1114 * If dirtyend exceeds file size, chop it down. This should 1115 * not normally occur but there is an append race where it 1116 * might occur XXX, so we log it. 1117 * 1118 * If the chopping creates a reverse-indexed or degenerate 1119 * situation with dirtyoff/end, we 0 both of them. 1120 */ 1121 1122 if (bp->b_dirtyend > bcount) { 1123 ncl_printf("NFS append race @%lx:%d\n", 1124 (long)bp->b_blkno * DEV_BSIZE, 1125 bp->b_dirtyend - bcount); 1126 bp->b_dirtyend = bcount; 1127 } 1128 1129 if (bp->b_dirtyoff >= bp->b_dirtyend) 1130 bp->b_dirtyoff = bp->b_dirtyend = 0; 1131 1132 /* 1133 * If the new write will leave a contiguous dirty 1134 * area, just update the b_dirtyoff and b_dirtyend, 1135 * otherwise force a write rpc of the old dirty area. 1136 * 1137 * If there has been a file lock applied to this file 1138 * or vfs.nfs.old_noncontig_writing is set, do the following: 1139 * While it is possible to merge discontiguous writes due to 1140 * our having a B_CACHE buffer ( and thus valid read data 1141 * for the hole), we don't because it could lead to 1142 * significant cache coherency problems with multiple clients, 1143 * especially if locking is implemented later on. 1144 * 1145 * If vfs.nfs.old_noncontig_writing is not set and there has 1146 * not been file locking done on this file: 1147 * Relax coherency a bit for the sake of performance and 1148 * expand the current dirty region to contain the new 1149 * write even if it means we mark some non-dirty data as 1150 * dirty. 1151 */ 1152 1153 if (noncontig_write == 0 && bp->b_dirtyend > 0 && 1154 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 1155 if (bwrite(bp) == EINTR) { 1156 error = EINTR; 1157 break; 1158 } 1159 goto again; 1160 } 1161 1162 local_resid = uio->uio_resid; 1163 error = vn_io_fault_uiomove((char *)bp->b_data + on, n, uio); 1164 1165 if (error != 0 && !bp_cached) { 1166 /* 1167 * This block has no other content then what 1168 * possibly was written by the faulty uiomove. 1169 * Release it, forgetting the data pages, to 1170 * prevent the leak of uninitialized data to 1171 * usermode. 1172 */ 1173 bp->b_ioflags |= BIO_ERROR; 1174 brelse(bp); 1175 uio->uio_offset -= local_resid - uio->uio_resid; 1176 uio->uio_resid = local_resid; 1177 break; 1178 } 1179 1180 /* 1181 * Since this block is being modified, it must be written 1182 * again and not just committed. Since write clustering does 1183 * not work for the stage 1 data write, only the stage 2 1184 * commit rpc, we have to clear B_CLUSTEROK as well. 1185 */ 1186 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1187 1188 /* 1189 * Get the partial update on the progress made from 1190 * uiomove, if an error occured. 1191 */ 1192 if (error != 0) 1193 n = local_resid - uio->uio_resid; 1194 1195 /* 1196 * Only update dirtyoff/dirtyend if not a degenerate 1197 * condition. 1198 */ 1199 if (n > 0) { 1200 if (bp->b_dirtyend > 0) { 1201 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 1202 bp->b_dirtyend = max((on + n), bp->b_dirtyend); 1203 } else { 1204 bp->b_dirtyoff = on; 1205 bp->b_dirtyend = on + n; 1206 } 1207 vfs_bio_set_valid(bp, on, n); 1208 } 1209 1210 /* 1211 * If IO_SYNC do bwrite(). 1212 * 1213 * IO_INVAL appears to be unused. The idea appears to be 1214 * to turn off caching in this case. Very odd. XXX 1215 */ 1216 if ((ioflag & IO_SYNC)) { 1217 if (ioflag & IO_INVAL) 1218 bp->b_flags |= B_NOCACHE; 1219 error1 = bwrite(bp); 1220 if (error1 != 0) { 1221 if (error == 0) 1222 error = error1; 1223 break; 1224 } 1225 } else if ((n + on) == biosize) { 1226 bp->b_flags |= B_ASYNC; 1227 (void) ncl_writebp(bp, 0, NULL); 1228 } else { 1229 bdwrite(bp); 1230 } 1231 1232 if (error != 0) 1233 break; 1234 } while (uio->uio_resid > 0 && n > 0); 1235 1236 if (error != 0) { 1237 if (ioflag & IO_UNIT) { 1238 VATTR_NULL(&vattr); 1239 vattr.va_size = orig_size; 1240 /* IO_SYNC is handled implicitely */ 1241 (void)VOP_SETATTR(vp, &vattr, cred); 1242 uio->uio_offset -= orig_resid - uio->uio_resid; 1243 uio->uio_resid = orig_resid; 1244 } 1245 } 1246 1247 return (error); 1248 } 1249 1250 /* 1251 * Get an nfs cache block. 1252 * 1253 * Allocate a new one if the block isn't currently in the cache 1254 * and return the block marked busy. If the calling process is 1255 * interrupted by a signal for an interruptible mount point, return 1256 * NULL. 1257 * 1258 * The caller must carefully deal with the possible B_INVAL state of 1259 * the buffer. ncl_doio() clears B_INVAL (and ncl_asyncio() clears it 1260 * indirectly), so synchronous reads can be issued without worrying about 1261 * the B_INVAL state. We have to be a little more careful when dealing 1262 * with writes (see comments in nfs_write()) when extending a file past 1263 * its EOF. 1264 */ 1265 static struct buf * 1266 nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td) 1267 { 1268 struct buf *bp; 1269 struct mount *mp; 1270 struct nfsmount *nmp; 1271 1272 mp = vp->v_mount; 1273 nmp = VFSTONFS(mp); 1274 1275 if (nmp->nm_flag & NFSMNT_INT) { 1276 sigset_t oldset; 1277 1278 newnfs_set_sigmask(td, &oldset); 1279 bp = getblk(vp, bn, size, PCATCH, 0, 0); 1280 newnfs_restore_sigmask(td, &oldset); 1281 while (bp == NULL) { 1282 if (newnfs_sigintr(nmp, td)) 1283 return (NULL); 1284 bp = getblk(vp, bn, size, 0, 2 * hz, 0); 1285 } 1286 } else { 1287 bp = getblk(vp, bn, size, 0, 0, 0); 1288 } 1289 1290 if (vp->v_type == VREG) 1291 bp->b_blkno = bn * (vp->v_bufobj.bo_bsize / DEV_BSIZE); 1292 return (bp); 1293 } 1294 1295 /* 1296 * Flush and invalidate all dirty buffers. If another process is already 1297 * doing the flush, just wait for completion. 1298 */ 1299 int 1300 ncl_vinvalbuf(struct vnode *vp, int flags, struct thread *td, int intrflg) 1301 { 1302 struct nfsnode *np = VTONFS(vp); 1303 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1304 int error = 0, slpflag, slptimeo; 1305 int old_lock = 0; 1306 1307 ASSERT_VOP_LOCKED(vp, "ncl_vinvalbuf"); 1308 1309 if ((nmp->nm_flag & NFSMNT_INT) == 0) 1310 intrflg = 0; 1311 if ((nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF)) 1312 intrflg = 1; 1313 if (intrflg) { 1314 slpflag = PCATCH; 1315 slptimeo = 2 * hz; 1316 } else { 1317 slpflag = 0; 1318 slptimeo = 0; 1319 } 1320 1321 old_lock = ncl_upgrade_vnlock(vp); 1322 if (vp->v_iflag & VI_DOOMED) { 1323 /* 1324 * Since vgonel() uses the generic vinvalbuf() to flush 1325 * dirty buffers and it does not call this function, it 1326 * is safe to just return OK when VI_DOOMED is set. 1327 */ 1328 ncl_downgrade_vnlock(vp, old_lock); 1329 return (0); 1330 } 1331 1332 /* 1333 * Now, flush as required. 1334 */ 1335 if ((flags & V_SAVE) && (vp->v_bufobj.bo_object != NULL)) { 1336 VM_OBJECT_WLOCK(vp->v_bufobj.bo_object); 1337 vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC); 1338 VM_OBJECT_WUNLOCK(vp->v_bufobj.bo_object); 1339 /* 1340 * If the page clean was interrupted, fail the invalidation. 1341 * Not doing so, we run the risk of losing dirty pages in the 1342 * vinvalbuf() call below. 1343 */ 1344 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1345 goto out; 1346 } 1347 1348 error = vinvalbuf(vp, flags, slpflag, 0); 1349 while (error) { 1350 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1351 goto out; 1352 error = vinvalbuf(vp, flags, 0, slptimeo); 1353 } 1354 if (NFSHASPNFS(nmp)) { 1355 nfscl_layoutcommit(vp, td); 1356 /* 1357 * Invalidate the attribute cache, since writes to a DS 1358 * won't update the size attribute. 1359 */ 1360 mtx_lock(&np->n_mtx); 1361 np->n_attrstamp = 0; 1362 } else 1363 mtx_lock(&np->n_mtx); 1364 if (np->n_directio_asyncwr == 0) 1365 np->n_flag &= ~NMODIFIED; 1366 mtx_unlock(&np->n_mtx); 1367 out: 1368 ncl_downgrade_vnlock(vp, old_lock); 1369 return error; 1370 } 1371 1372 /* 1373 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 1374 * This is mainly to avoid queueing async I/O requests when the nfsiods 1375 * are all hung on a dead server. 1376 * 1377 * Note: ncl_asyncio() does not clear (BIO_ERROR|B_INVAL) but when the bp 1378 * is eventually dequeued by the async daemon, ncl_doio() *will*. 1379 */ 1380 int 1381 ncl_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td) 1382 { 1383 int iod; 1384 int gotiod; 1385 int slpflag = 0; 1386 int slptimeo = 0; 1387 int error, error2; 1388 1389 /* 1390 * Commits are usually short and sweet so lets save some cpu and 1391 * leave the async daemons for more important rpc's (such as reads 1392 * and writes). 1393 * 1394 * Readdirplus RPCs do vget()s to acquire the vnodes for entries 1395 * in the directory in order to update attributes. This can deadlock 1396 * with another thread that is waiting for async I/O to be done by 1397 * an nfsiod thread while holding a lock on one of these vnodes. 1398 * To avoid this deadlock, don't allow the async nfsiod threads to 1399 * perform Readdirplus RPCs. 1400 */ 1401 mtx_lock(&ncl_iod_mutex); 1402 if ((bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) && 1403 (nmp->nm_bufqiods > ncl_numasync / 2)) || 1404 (bp->b_vp->v_type == VDIR && (nmp->nm_flag & NFSMNT_RDIRPLUS))) { 1405 mtx_unlock(&ncl_iod_mutex); 1406 return(EIO); 1407 } 1408 again: 1409 if (nmp->nm_flag & NFSMNT_INT) 1410 slpflag = PCATCH; 1411 gotiod = FALSE; 1412 1413 /* 1414 * Find a free iod to process this request. 1415 */ 1416 for (iod = 0; iod < ncl_numasync; iod++) 1417 if (ncl_iodwant[iod] == NFSIOD_AVAILABLE) { 1418 gotiod = TRUE; 1419 break; 1420 } 1421 1422 /* 1423 * Try to create one if none are free. 1424 */ 1425 if (!gotiod) 1426 ncl_nfsiodnew(); 1427 else { 1428 /* 1429 * Found one, so wake it up and tell it which 1430 * mount to process. 1431 */ 1432 NFS_DPF(ASYNCIO, ("ncl_asyncio: waking iod %d for mount %p\n", 1433 iod, nmp)); 1434 ncl_iodwant[iod] = NFSIOD_NOT_AVAILABLE; 1435 ncl_iodmount[iod] = nmp; 1436 nmp->nm_bufqiods++; 1437 wakeup(&ncl_iodwant[iod]); 1438 } 1439 1440 /* 1441 * If none are free, we may already have an iod working on this mount 1442 * point. If so, it will process our request. 1443 */ 1444 if (!gotiod) { 1445 if (nmp->nm_bufqiods > 0) { 1446 NFS_DPF(ASYNCIO, 1447 ("ncl_asyncio: %d iods are already processing mount %p\n", 1448 nmp->nm_bufqiods, nmp)); 1449 gotiod = TRUE; 1450 } 1451 } 1452 1453 /* 1454 * If we have an iod which can process the request, then queue 1455 * the buffer. 1456 */ 1457 if (gotiod) { 1458 /* 1459 * Ensure that the queue never grows too large. We still want 1460 * to asynchronize so we block rather then return EIO. 1461 */ 1462 while (nmp->nm_bufqlen >= 2*ncl_numasync) { 1463 NFS_DPF(ASYNCIO, 1464 ("ncl_asyncio: waiting for mount %p queue to drain\n", nmp)); 1465 nmp->nm_bufqwant = TRUE; 1466 error = newnfs_msleep(td, &nmp->nm_bufq, 1467 &ncl_iod_mutex, slpflag | PRIBIO, "nfsaio", 1468 slptimeo); 1469 if (error) { 1470 error2 = newnfs_sigintr(nmp, td); 1471 if (error2) { 1472 mtx_unlock(&ncl_iod_mutex); 1473 return (error2); 1474 } 1475 if (slpflag == PCATCH) { 1476 slpflag = 0; 1477 slptimeo = 2 * hz; 1478 } 1479 } 1480 /* 1481 * We might have lost our iod while sleeping, 1482 * so check and loop if nescessary. 1483 */ 1484 goto again; 1485 } 1486 1487 /* We might have lost our nfsiod */ 1488 if (nmp->nm_bufqiods == 0) { 1489 NFS_DPF(ASYNCIO, 1490 ("ncl_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); 1491 goto again; 1492 } 1493 1494 if (bp->b_iocmd == BIO_READ) { 1495 if (bp->b_rcred == NOCRED && cred != NOCRED) 1496 bp->b_rcred = crhold(cred); 1497 } else { 1498 if (bp->b_wcred == NOCRED && cred != NOCRED) 1499 bp->b_wcred = crhold(cred); 1500 } 1501 1502 if (bp->b_flags & B_REMFREE) 1503 bremfreef(bp); 1504 BUF_KERNPROC(bp); 1505 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 1506 nmp->nm_bufqlen++; 1507 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1508 mtx_lock(&(VTONFS(bp->b_vp))->n_mtx); 1509 VTONFS(bp->b_vp)->n_flag |= NMODIFIED; 1510 VTONFS(bp->b_vp)->n_directio_asyncwr++; 1511 mtx_unlock(&(VTONFS(bp->b_vp))->n_mtx); 1512 } 1513 mtx_unlock(&ncl_iod_mutex); 1514 return (0); 1515 } 1516 1517 mtx_unlock(&ncl_iod_mutex); 1518 1519 /* 1520 * All the iods are busy on other mounts, so return EIO to 1521 * force the caller to process the i/o synchronously. 1522 */ 1523 NFS_DPF(ASYNCIO, ("ncl_asyncio: no iods available, i/o is synchronous\n")); 1524 return (EIO); 1525 } 1526 1527 void 1528 ncl_doio_directwrite(struct buf *bp) 1529 { 1530 int iomode, must_commit; 1531 struct uio *uiop = (struct uio *)bp->b_caller1; 1532 char *iov_base = uiop->uio_iov->iov_base; 1533 1534 iomode = NFSWRITE_FILESYNC; 1535 uiop->uio_td = NULL; /* NULL since we're in nfsiod */ 1536 ncl_writerpc(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit, 0); 1537 KASSERT((must_commit == 0), ("ncl_doio_directwrite: Did not commit write")); 1538 free(iov_base, M_NFSDIRECTIO); 1539 free(uiop->uio_iov, M_NFSDIRECTIO); 1540 free(uiop, M_NFSDIRECTIO); 1541 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1542 struct nfsnode *np = VTONFS(bp->b_vp); 1543 mtx_lock(&np->n_mtx); 1544 if (NFSHASPNFS(VFSTONFS(vnode_mount(bp->b_vp)))) { 1545 /* 1546 * Invalidate the attribute cache, since writes to a DS 1547 * won't update the size attribute. 1548 */ 1549 np->n_attrstamp = 0; 1550 } 1551 np->n_directio_asyncwr--; 1552 if (np->n_directio_asyncwr == 0) { 1553 np->n_flag &= ~NMODIFIED; 1554 if ((np->n_flag & NFSYNCWAIT)) { 1555 np->n_flag &= ~NFSYNCWAIT; 1556 wakeup((caddr_t)&np->n_directio_asyncwr); 1557 } 1558 } 1559 mtx_unlock(&np->n_mtx); 1560 } 1561 bp->b_vp = NULL; 1562 relpbuf(bp, &ncl_pbuf_freecnt); 1563 } 1564 1565 /* 1566 * Do an I/O operation to/from a cache block. This may be called 1567 * synchronously or from an nfsiod. 1568 */ 1569 int 1570 ncl_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td, 1571 int called_from_strategy) 1572 { 1573 struct uio *uiop; 1574 struct nfsnode *np; 1575 struct nfsmount *nmp; 1576 int error = 0, iomode, must_commit = 0; 1577 struct uio uio; 1578 struct iovec io; 1579 struct proc *p = td ? td->td_proc : NULL; 1580 uint8_t iocmd; 1581 1582 np = VTONFS(vp); 1583 nmp = VFSTONFS(vp->v_mount); 1584 uiop = &uio; 1585 uiop->uio_iov = &io; 1586 uiop->uio_iovcnt = 1; 1587 uiop->uio_segflg = UIO_SYSSPACE; 1588 uiop->uio_td = td; 1589 1590 /* 1591 * clear BIO_ERROR and B_INVAL state prior to initiating the I/O. We 1592 * do this here so we do not have to do it in all the code that 1593 * calls us. 1594 */ 1595 bp->b_flags &= ~B_INVAL; 1596 bp->b_ioflags &= ~BIO_ERROR; 1597 1598 KASSERT(!(bp->b_flags & B_DONE), ("ncl_doio: bp %p already marked done", bp)); 1599 iocmd = bp->b_iocmd; 1600 if (iocmd == BIO_READ) { 1601 io.iov_len = uiop->uio_resid = bp->b_bcount; 1602 io.iov_base = bp->b_data; 1603 uiop->uio_rw = UIO_READ; 1604 1605 switch (vp->v_type) { 1606 case VREG: 1607 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1608 NFSINCRGLOBAL(newnfsstats.read_bios); 1609 error = ncl_readrpc(vp, uiop, cr); 1610 1611 if (!error) { 1612 if (uiop->uio_resid) { 1613 /* 1614 * If we had a short read with no error, we must have 1615 * hit a file hole. We should zero-fill the remainder. 1616 * This can also occur if the server hits the file EOF. 1617 * 1618 * Holes used to be able to occur due to pending 1619 * writes, but that is not possible any longer. 1620 */ 1621 int nread = bp->b_bcount - uiop->uio_resid; 1622 ssize_t left = uiop->uio_resid; 1623 1624 if (left > 0) 1625 bzero((char *)bp->b_data + nread, left); 1626 uiop->uio_resid = 0; 1627 } 1628 } 1629 /* ASSERT_VOP_LOCKED(vp, "ncl_doio"); */ 1630 if (p && (vp->v_vflag & VV_TEXT)) { 1631 mtx_lock(&np->n_mtx); 1632 if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.na_mtime)) { 1633 mtx_unlock(&np->n_mtx); 1634 PROC_LOCK(p); 1635 killproc(p, "text file modification"); 1636 PROC_UNLOCK(p); 1637 } else 1638 mtx_unlock(&np->n_mtx); 1639 } 1640 break; 1641 case VLNK: 1642 uiop->uio_offset = (off_t)0; 1643 NFSINCRGLOBAL(newnfsstats.readlink_bios); 1644 error = ncl_readlinkrpc(vp, uiop, cr); 1645 break; 1646 case VDIR: 1647 NFSINCRGLOBAL(newnfsstats.readdir_bios); 1648 uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ; 1649 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) != 0) { 1650 error = ncl_readdirplusrpc(vp, uiop, cr, td); 1651 if (error == NFSERR_NOTSUPP) 1652 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 1653 } 1654 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 1655 error = ncl_readdirrpc(vp, uiop, cr, td); 1656 /* 1657 * end-of-directory sets B_INVAL but does not generate an 1658 * error. 1659 */ 1660 if (error == 0 && uiop->uio_resid == bp->b_bcount) 1661 bp->b_flags |= B_INVAL; 1662 break; 1663 default: 1664 ncl_printf("ncl_doio: type %x unexpected\n", vp->v_type); 1665 break; 1666 }; 1667 if (error) { 1668 bp->b_ioflags |= BIO_ERROR; 1669 bp->b_error = error; 1670 } 1671 } else { 1672 /* 1673 * If we only need to commit, try to commit 1674 */ 1675 if (bp->b_flags & B_NEEDCOMMIT) { 1676 int retv; 1677 off_t off; 1678 1679 off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff; 1680 retv = ncl_commit(vp, off, bp->b_dirtyend-bp->b_dirtyoff, 1681 bp->b_wcred, td); 1682 if (retv == 0) { 1683 bp->b_dirtyoff = bp->b_dirtyend = 0; 1684 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1685 bp->b_resid = 0; 1686 bufdone(bp); 1687 return (0); 1688 } 1689 if (retv == NFSERR_STALEWRITEVERF) { 1690 ncl_clearcommit(vp->v_mount); 1691 } 1692 } 1693 1694 /* 1695 * Setup for actual write 1696 */ 1697 mtx_lock(&np->n_mtx); 1698 if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size) 1699 bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE; 1700 mtx_unlock(&np->n_mtx); 1701 1702 if (bp->b_dirtyend > bp->b_dirtyoff) { 1703 io.iov_len = uiop->uio_resid = bp->b_dirtyend 1704 - bp->b_dirtyoff; 1705 uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE 1706 + bp->b_dirtyoff; 1707 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 1708 uiop->uio_rw = UIO_WRITE; 1709 NFSINCRGLOBAL(newnfsstats.write_bios); 1710 1711 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC) 1712 iomode = NFSWRITE_UNSTABLE; 1713 else 1714 iomode = NFSWRITE_FILESYNC; 1715 1716 error = ncl_writerpc(vp, uiop, cr, &iomode, &must_commit, 1717 called_from_strategy); 1718 1719 /* 1720 * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try 1721 * to cluster the buffers needing commit. This will allow 1722 * the system to submit a single commit rpc for the whole 1723 * cluster. We can do this even if the buffer is not 100% 1724 * dirty (relative to the NFS blocksize), so we optimize the 1725 * append-to-file-case. 1726 * 1727 * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be 1728 * cleared because write clustering only works for commit 1729 * rpc's, not for the data portion of the write). 1730 */ 1731 1732 if (!error && iomode == NFSWRITE_UNSTABLE) { 1733 bp->b_flags |= B_NEEDCOMMIT; 1734 if (bp->b_dirtyoff == 0 1735 && bp->b_dirtyend == bp->b_bcount) 1736 bp->b_flags |= B_CLUSTEROK; 1737 } else { 1738 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1739 } 1740 1741 /* 1742 * For an interrupted write, the buffer is still valid 1743 * and the write hasn't been pushed to the server yet, 1744 * so we can't set BIO_ERROR and report the interruption 1745 * by setting B_EINTR. For the B_ASYNC case, B_EINTR 1746 * is not relevant, so the rpc attempt is essentially 1747 * a noop. For the case of a V3 write rpc not being 1748 * committed to stable storage, the block is still 1749 * dirty and requires either a commit rpc or another 1750 * write rpc with iomode == NFSV3WRITE_FILESYNC before 1751 * the block is reused. This is indicated by setting 1752 * the B_DELWRI and B_NEEDCOMMIT flags. 1753 * 1754 * EIO is returned by ncl_writerpc() to indicate a recoverable 1755 * write error and is handled as above, except that 1756 * B_EINTR isn't set. One cause of this is a stale stateid 1757 * error for the RPC that indicates recovery is required, 1758 * when called with called_from_strategy != 0. 1759 * 1760 * If the buffer is marked B_PAGING, it does not reside on 1761 * the vp's paging queues so we cannot call bdirty(). The 1762 * bp in this case is not an NFS cache block so we should 1763 * be safe. XXX 1764 * 1765 * The logic below breaks up errors into recoverable and 1766 * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE 1767 * and keep the buffer around for potential write retries. 1768 * For the latter (eg ESTALE), we toss the buffer away (B_INVAL) 1769 * and save the error in the nfsnode. This is less than ideal 1770 * but necessary. Keeping such buffers around could potentially 1771 * cause buffer exhaustion eventually (they can never be written 1772 * out, so will get constantly be re-dirtied). It also causes 1773 * all sorts of vfs panics. For non-recoverable write errors, 1774 * also invalidate the attrcache, so we'll be forced to go over 1775 * the wire for this object, returning an error to user on next 1776 * call (most of the time). 1777 */ 1778 if (error == EINTR || error == EIO || error == ETIMEDOUT 1779 || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 1780 int s; 1781 1782 s = splbio(); 1783 bp->b_flags &= ~(B_INVAL|B_NOCACHE); 1784 if ((bp->b_flags & B_PAGING) == 0) { 1785 bdirty(bp); 1786 bp->b_flags &= ~B_DONE; 1787 } 1788 if ((error == EINTR || error == ETIMEDOUT) && 1789 (bp->b_flags & B_ASYNC) == 0) 1790 bp->b_flags |= B_EINTR; 1791 splx(s); 1792 } else { 1793 if (error) { 1794 bp->b_ioflags |= BIO_ERROR; 1795 bp->b_flags |= B_INVAL; 1796 bp->b_error = np->n_error = error; 1797 mtx_lock(&np->n_mtx); 1798 np->n_flag |= NWRITEERR; 1799 np->n_attrstamp = 0; 1800 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 1801 mtx_unlock(&np->n_mtx); 1802 } 1803 bp->b_dirtyoff = bp->b_dirtyend = 0; 1804 } 1805 } else { 1806 bp->b_resid = 0; 1807 bufdone(bp); 1808 return (0); 1809 } 1810 } 1811 bp->b_resid = uiop->uio_resid; 1812 if (must_commit) 1813 ncl_clearcommit(vp->v_mount); 1814 bufdone(bp); 1815 return (error); 1816 } 1817 1818 /* 1819 * Used to aid in handling ftruncate() operations on the NFS client side. 1820 * Truncation creates a number of special problems for NFS. We have to 1821 * throw away VM pages and buffer cache buffers that are beyond EOF, and 1822 * we have to properly handle VM pages or (potentially dirty) buffers 1823 * that straddle the truncation point. 1824 */ 1825 1826 int 1827 ncl_meta_setsize(struct vnode *vp, struct ucred *cred, struct thread *td, u_quad_t nsize) 1828 { 1829 struct nfsnode *np = VTONFS(vp); 1830 u_quad_t tsize; 1831 int biosize = vp->v_bufobj.bo_bsize; 1832 int error = 0; 1833 1834 mtx_lock(&np->n_mtx); 1835 tsize = np->n_size; 1836 np->n_size = nsize; 1837 mtx_unlock(&np->n_mtx); 1838 1839 if (nsize < tsize) { 1840 struct buf *bp; 1841 daddr_t lbn; 1842 int bufsize; 1843 1844 /* 1845 * vtruncbuf() doesn't get the buffer overlapping the 1846 * truncation point. We may have a B_DELWRI and/or B_CACHE 1847 * buffer that now needs to be truncated. 1848 */ 1849 error = vtruncbuf(vp, cred, nsize, biosize); 1850 lbn = nsize / biosize; 1851 bufsize = nsize - (lbn * biosize); 1852 bp = nfs_getcacheblk(vp, lbn, bufsize, td); 1853 if (!bp) 1854 return EINTR; 1855 if (bp->b_dirtyoff > bp->b_bcount) 1856 bp->b_dirtyoff = bp->b_bcount; 1857 if (bp->b_dirtyend > bp->b_bcount) 1858 bp->b_dirtyend = bp->b_bcount; 1859 bp->b_flags |= B_RELBUF; /* don't leave garbage around */ 1860 brelse(bp); 1861 } else { 1862 vnode_pager_setsize(vp, nsize); 1863 } 1864 return(error); 1865 } 1866 1867