1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Rick Macklem at The University of Guelph. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/bio.h> 43 #include <sys/buf.h> 44 #include <sys/kernel.h> 45 #include <sys/mount.h> 46 #include <sys/rwlock.h> 47 #include <sys/vmmeter.h> 48 #include <sys/vnode.h> 49 50 #include <vm/vm.h> 51 #include <vm/vm_param.h> 52 #include <vm/vm_extern.h> 53 #include <vm/vm_page.h> 54 #include <vm/vm_object.h> 55 #include <vm/vm_pager.h> 56 #include <vm/vnode_pager.h> 57 58 #include <fs/nfs/nfsport.h> 59 #include <fs/nfsclient/nfsmount.h> 60 #include <fs/nfsclient/nfs.h> 61 #include <fs/nfsclient/nfsnode.h> 62 #include <fs/nfsclient/nfs_kdtrace.h> 63 64 extern int newnfs_directio_allow_mmap; 65 extern struct nfsstatsv1 nfsstatsv1; 66 extern struct mtx ncl_iod_mutex; 67 extern int ncl_numasync; 68 extern enum nfsiod_state ncl_iodwant[NFS_MAXASYNCDAEMON]; 69 extern struct nfsmount *ncl_iodmount[NFS_MAXASYNCDAEMON]; 70 extern int newnfs_directio_enable; 71 extern int nfs_keep_dirty_on_error; 72 73 int ncl_pbuf_freecnt = -1; /* start out unlimited */ 74 75 static struct buf *nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, 76 struct thread *td); 77 static int nfs_directio_write(struct vnode *vp, struct uio *uiop, 78 struct ucred *cred, int ioflag); 79 80 /* 81 * Vnode op for VM getpages. 82 */ 83 SYSCTL_DECL(_vfs_nfs); 84 static int use_buf_pager = 1; 85 SYSCTL_INT(_vfs_nfs, OID_AUTO, use_buf_pager, CTLFLAG_RWTUN, 86 &use_buf_pager, 0, 87 "Use buffer pager instead of direct readrpc call"); 88 89 static daddr_t 90 ncl_gbp_getblkno(struct vnode *vp, vm_ooffset_t off) 91 { 92 93 return (off / vp->v_bufobj.bo_bsize); 94 } 95 96 static int 97 ncl_gbp_getblksz(struct vnode *vp, daddr_t lbn) 98 { 99 struct nfsnode *np; 100 u_quad_t nsize; 101 int biosize, bcount; 102 103 np = VTONFS(vp); 104 mtx_lock(&np->n_mtx); 105 nsize = np->n_size; 106 mtx_unlock(&np->n_mtx); 107 108 biosize = vp->v_bufobj.bo_bsize; 109 bcount = biosize; 110 if ((off_t)lbn * biosize >= nsize) 111 bcount = 0; 112 else if ((off_t)(lbn + 1) * biosize > nsize) 113 bcount = nsize - (off_t)lbn * biosize; 114 return (bcount); 115 } 116 117 int 118 ncl_getpages(struct vop_getpages_args *ap) 119 { 120 int i, error, nextoff, size, toff, count, npages; 121 struct uio uio; 122 struct iovec iov; 123 vm_offset_t kva; 124 struct buf *bp; 125 struct vnode *vp; 126 struct thread *td; 127 struct ucred *cred; 128 struct nfsmount *nmp; 129 vm_object_t object; 130 vm_page_t *pages; 131 struct nfsnode *np; 132 133 vp = ap->a_vp; 134 np = VTONFS(vp); 135 td = curthread; 136 cred = curthread->td_ucred; 137 nmp = VFSTONFS(vp->v_mount); 138 pages = ap->a_m; 139 npages = ap->a_count; 140 141 if ((object = vp->v_object) == NULL) { 142 printf("ncl_getpages: called with non-merged cache vnode\n"); 143 return (VM_PAGER_ERROR); 144 } 145 146 if (newnfs_directio_enable && !newnfs_directio_allow_mmap) { 147 mtx_lock(&np->n_mtx); 148 if ((np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 149 mtx_unlock(&np->n_mtx); 150 printf("ncl_getpages: called on non-cacheable vnode\n"); 151 return (VM_PAGER_ERROR); 152 } else 153 mtx_unlock(&np->n_mtx); 154 } 155 156 mtx_lock(&nmp->nm_mtx); 157 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 158 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 159 mtx_unlock(&nmp->nm_mtx); 160 /* We'll never get here for v4, because we always have fsinfo */ 161 (void)ncl_fsinfo(nmp, vp, cred, td); 162 } else 163 mtx_unlock(&nmp->nm_mtx); 164 165 if (use_buf_pager) 166 return (vfs_bio_getpages(vp, pages, npages, ap->a_rbehind, 167 ap->a_rahead, ncl_gbp_getblkno, ncl_gbp_getblksz)); 168 169 /* 170 * If the requested page is partially valid, just return it and 171 * allow the pager to zero-out the blanks. Partially valid pages 172 * can only occur at the file EOF. 173 * 174 * XXXGL: is that true for NFS, where short read can occur??? 175 */ 176 VM_OBJECT_WLOCK(object); 177 if (pages[npages - 1]->valid != 0 && --npages == 0) 178 goto out; 179 VM_OBJECT_WUNLOCK(object); 180 181 /* 182 * We use only the kva address for the buffer, but this is extremely 183 * convenient and fast. 184 */ 185 bp = getpbuf(&ncl_pbuf_freecnt); 186 187 kva = (vm_offset_t) bp->b_data; 188 pmap_qenter(kva, pages, npages); 189 VM_CNT_INC(v_vnodein); 190 VM_CNT_ADD(v_vnodepgsin, npages); 191 192 count = npages << PAGE_SHIFT; 193 iov.iov_base = (caddr_t) kva; 194 iov.iov_len = count; 195 uio.uio_iov = &iov; 196 uio.uio_iovcnt = 1; 197 uio.uio_offset = IDX_TO_OFF(pages[0]->pindex); 198 uio.uio_resid = count; 199 uio.uio_segflg = UIO_SYSSPACE; 200 uio.uio_rw = UIO_READ; 201 uio.uio_td = td; 202 203 error = ncl_readrpc(vp, &uio, cred); 204 pmap_qremove(kva, npages); 205 206 relpbuf(bp, &ncl_pbuf_freecnt); 207 208 if (error && (uio.uio_resid == count)) { 209 printf("ncl_getpages: error %d\n", error); 210 return (VM_PAGER_ERROR); 211 } 212 213 /* 214 * Calculate the number of bytes read and validate only that number 215 * of bytes. Note that due to pending writes, size may be 0. This 216 * does not mean that the remaining data is invalid! 217 */ 218 219 size = count - uio.uio_resid; 220 VM_OBJECT_WLOCK(object); 221 for (i = 0, toff = 0; i < npages; i++, toff = nextoff) { 222 vm_page_t m; 223 nextoff = toff + PAGE_SIZE; 224 m = pages[i]; 225 226 if (nextoff <= size) { 227 /* 228 * Read operation filled an entire page 229 */ 230 m->valid = VM_PAGE_BITS_ALL; 231 KASSERT(m->dirty == 0, 232 ("nfs_getpages: page %p is dirty", m)); 233 } else if (size > toff) { 234 /* 235 * Read operation filled a partial page. 236 */ 237 m->valid = 0; 238 vm_page_set_valid_range(m, 0, size - toff); 239 KASSERT(m->dirty == 0, 240 ("nfs_getpages: page %p is dirty", m)); 241 } else { 242 /* 243 * Read operation was short. If no error 244 * occurred we may have hit a zero-fill 245 * section. We leave valid set to 0, and page 246 * is freed by vm_page_readahead_finish() if 247 * its index is not equal to requested, or 248 * page is zeroed and set valid by 249 * vm_pager_get_pages() for requested page. 250 */ 251 ; 252 } 253 } 254 out: 255 VM_OBJECT_WUNLOCK(object); 256 if (ap->a_rbehind) 257 *ap->a_rbehind = 0; 258 if (ap->a_rahead) 259 *ap->a_rahead = 0; 260 return (VM_PAGER_OK); 261 } 262 263 /* 264 * Vnode op for VM putpages. 265 */ 266 int 267 ncl_putpages(struct vop_putpages_args *ap) 268 { 269 struct uio uio; 270 struct iovec iov; 271 int i, error, npages, count; 272 off_t offset; 273 int *rtvals; 274 struct vnode *vp; 275 struct thread *td; 276 struct ucred *cred; 277 struct nfsmount *nmp; 278 struct nfsnode *np; 279 vm_page_t *pages; 280 281 vp = ap->a_vp; 282 np = VTONFS(vp); 283 td = curthread; /* XXX */ 284 /* Set the cred to n_writecred for the write rpcs. */ 285 if (np->n_writecred != NULL) 286 cred = crhold(np->n_writecred); 287 else 288 cred = crhold(curthread->td_ucred); /* XXX */ 289 nmp = VFSTONFS(vp->v_mount); 290 pages = ap->a_m; 291 count = ap->a_count; 292 rtvals = ap->a_rtvals; 293 npages = btoc(count); 294 offset = IDX_TO_OFF(pages[0]->pindex); 295 296 mtx_lock(&nmp->nm_mtx); 297 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 298 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 299 mtx_unlock(&nmp->nm_mtx); 300 (void)ncl_fsinfo(nmp, vp, cred, td); 301 } else 302 mtx_unlock(&nmp->nm_mtx); 303 304 mtx_lock(&np->n_mtx); 305 if (newnfs_directio_enable && !newnfs_directio_allow_mmap && 306 (np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 307 mtx_unlock(&np->n_mtx); 308 printf("ncl_putpages: called on noncache-able vnode\n"); 309 mtx_lock(&np->n_mtx); 310 } 311 /* 312 * When putting pages, do not extend file past EOF. 313 */ 314 if (offset + count > np->n_size) { 315 count = np->n_size - offset; 316 if (count < 0) 317 count = 0; 318 } 319 mtx_unlock(&np->n_mtx); 320 321 for (i = 0; i < npages; i++) 322 rtvals[i] = VM_PAGER_ERROR; 323 324 VM_CNT_INC(v_vnodeout); 325 VM_CNT_ADD(v_vnodepgsout, count); 326 327 iov.iov_base = unmapped_buf; 328 iov.iov_len = count; 329 uio.uio_iov = &iov; 330 uio.uio_iovcnt = 1; 331 uio.uio_offset = offset; 332 uio.uio_resid = count; 333 uio.uio_segflg = UIO_NOCOPY; 334 uio.uio_rw = UIO_WRITE; 335 uio.uio_td = td; 336 337 error = VOP_WRITE(vp, &uio, vnode_pager_putpages_ioflags(ap->a_sync), 338 cred); 339 crfree(cred); 340 341 if (error == 0 || !nfs_keep_dirty_on_error) { 342 vnode_pager_undirty_pages(pages, rtvals, count - uio.uio_resid, 343 np->n_size - offset, npages * PAGE_SIZE); 344 } 345 return (rtvals[0]); 346 } 347 348 /* 349 * For nfs, cache consistency can only be maintained approximately. 350 * Although RFC1094 does not specify the criteria, the following is 351 * believed to be compatible with the reference port. 352 * For nfs: 353 * If the file's modify time on the server has changed since the 354 * last read rpc or you have written to the file, 355 * you may have lost data cache consistency with the 356 * server, so flush all of the file's data out of the cache. 357 * Then force a getattr rpc to ensure that you have up to date 358 * attributes. 359 * NB: This implies that cache data can be read when up to 360 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 361 * attributes this could be forced by setting n_attrstamp to 0 before 362 * the VOP_GETATTR() call. 363 */ 364 static inline int 365 nfs_bioread_check_cons(struct vnode *vp, struct thread *td, struct ucred *cred) 366 { 367 int error = 0; 368 struct vattr vattr; 369 struct nfsnode *np = VTONFS(vp); 370 bool old_lock; 371 372 /* 373 * Ensure the exclusove access to the node before checking 374 * whether the cache is consistent. 375 */ 376 old_lock = ncl_excl_start(vp); 377 mtx_lock(&np->n_mtx); 378 if (np->n_flag & NMODIFIED) { 379 mtx_unlock(&np->n_mtx); 380 if (vp->v_type != VREG) { 381 if (vp->v_type != VDIR) 382 panic("nfs: bioread, not dir"); 383 ncl_invaldir(vp); 384 error = ncl_vinvalbuf(vp, V_SAVE | V_ALLOWCLEAN, td, 1); 385 if (error != 0) 386 goto out; 387 } 388 np->n_attrstamp = 0; 389 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 390 error = VOP_GETATTR(vp, &vattr, cred); 391 if (error) 392 goto out; 393 mtx_lock(&np->n_mtx); 394 np->n_mtime = vattr.va_mtime; 395 mtx_unlock(&np->n_mtx); 396 } else { 397 mtx_unlock(&np->n_mtx); 398 error = VOP_GETATTR(vp, &vattr, cred); 399 if (error) 400 goto out; 401 mtx_lock(&np->n_mtx); 402 if ((np->n_flag & NSIZECHANGED) 403 || (NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime))) { 404 mtx_unlock(&np->n_mtx); 405 if (vp->v_type == VDIR) 406 ncl_invaldir(vp); 407 error = ncl_vinvalbuf(vp, V_SAVE | V_ALLOWCLEAN, td, 1); 408 if (error != 0) 409 goto out; 410 mtx_lock(&np->n_mtx); 411 np->n_mtime = vattr.va_mtime; 412 np->n_flag &= ~NSIZECHANGED; 413 } 414 mtx_unlock(&np->n_mtx); 415 } 416 out: 417 ncl_excl_finish(vp, old_lock); 418 return (error); 419 } 420 421 /* 422 * Vnode op for read using bio 423 */ 424 int 425 ncl_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred) 426 { 427 struct nfsnode *np = VTONFS(vp); 428 int biosize, i; 429 struct buf *bp, *rabp; 430 struct thread *td; 431 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 432 daddr_t lbn, rabn; 433 int bcount; 434 int seqcount; 435 int nra, error = 0, n = 0, on = 0; 436 off_t tmp_off; 437 438 KASSERT(uio->uio_rw == UIO_READ, ("ncl_read mode")); 439 if (uio->uio_resid == 0) 440 return (0); 441 if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */ 442 return (EINVAL); 443 td = uio->uio_td; 444 445 mtx_lock(&nmp->nm_mtx); 446 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 447 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 448 mtx_unlock(&nmp->nm_mtx); 449 (void)ncl_fsinfo(nmp, vp, cred, td); 450 mtx_lock(&nmp->nm_mtx); 451 } 452 if (nmp->nm_rsize == 0 || nmp->nm_readdirsize == 0) 453 (void) newnfs_iosize(nmp); 454 455 tmp_off = uio->uio_offset + uio->uio_resid; 456 if (vp->v_type != VDIR && 457 (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset)) { 458 mtx_unlock(&nmp->nm_mtx); 459 return (EFBIG); 460 } 461 mtx_unlock(&nmp->nm_mtx); 462 463 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && (vp->v_type == VREG)) 464 /* No caching/ no readaheads. Just read data into the user buffer */ 465 return ncl_readrpc(vp, uio, cred); 466 467 biosize = vp->v_bufobj.bo_bsize; 468 seqcount = (int)((off_t)(ioflag >> IO_SEQSHIFT) * biosize / BKVASIZE); 469 470 error = nfs_bioread_check_cons(vp, td, cred); 471 if (error) 472 return error; 473 474 do { 475 u_quad_t nsize; 476 477 mtx_lock(&np->n_mtx); 478 nsize = np->n_size; 479 mtx_unlock(&np->n_mtx); 480 481 switch (vp->v_type) { 482 case VREG: 483 NFSINCRGLOBAL(nfsstatsv1.biocache_reads); 484 lbn = uio->uio_offset / biosize; 485 on = uio->uio_offset - (lbn * biosize); 486 487 /* 488 * Start the read ahead(s), as required. 489 */ 490 if (nmp->nm_readahead > 0) { 491 for (nra = 0; nra < nmp->nm_readahead && nra < seqcount && 492 (off_t)(lbn + 1 + nra) * biosize < nsize; nra++) { 493 rabn = lbn + 1 + nra; 494 if (incore(&vp->v_bufobj, rabn) == NULL) { 495 rabp = nfs_getcacheblk(vp, rabn, biosize, td); 496 if (!rabp) { 497 error = newnfs_sigintr(nmp, td); 498 return (error ? error : EINTR); 499 } 500 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 501 rabp->b_flags |= B_ASYNC; 502 rabp->b_iocmd = BIO_READ; 503 vfs_busy_pages(rabp, 0); 504 if (ncl_asyncio(nmp, rabp, cred, td)) { 505 rabp->b_flags |= B_INVAL; 506 rabp->b_ioflags |= BIO_ERROR; 507 vfs_unbusy_pages(rabp); 508 brelse(rabp); 509 break; 510 } 511 } else { 512 brelse(rabp); 513 } 514 } 515 } 516 } 517 518 /* Note that bcount is *not* DEV_BSIZE aligned. */ 519 bcount = biosize; 520 if ((off_t)lbn * biosize >= nsize) { 521 bcount = 0; 522 } else if ((off_t)(lbn + 1) * biosize > nsize) { 523 bcount = nsize - (off_t)lbn * biosize; 524 } 525 bp = nfs_getcacheblk(vp, lbn, bcount, td); 526 527 if (!bp) { 528 error = newnfs_sigintr(nmp, td); 529 return (error ? error : EINTR); 530 } 531 532 /* 533 * If B_CACHE is not set, we must issue the read. If this 534 * fails, we return an error. 535 */ 536 537 if ((bp->b_flags & B_CACHE) == 0) { 538 bp->b_iocmd = BIO_READ; 539 vfs_busy_pages(bp, 0); 540 error = ncl_doio(vp, bp, cred, td, 0); 541 if (error) { 542 brelse(bp); 543 return (error); 544 } 545 } 546 547 /* 548 * on is the offset into the current bp. Figure out how many 549 * bytes we can copy out of the bp. Note that bcount is 550 * NOT DEV_BSIZE aligned. 551 * 552 * Then figure out how many bytes we can copy into the uio. 553 */ 554 555 n = 0; 556 if (on < bcount) 557 n = MIN((unsigned)(bcount - on), uio->uio_resid); 558 break; 559 case VLNK: 560 NFSINCRGLOBAL(nfsstatsv1.biocache_readlinks); 561 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, td); 562 if (!bp) { 563 error = newnfs_sigintr(nmp, td); 564 return (error ? error : EINTR); 565 } 566 if ((bp->b_flags & B_CACHE) == 0) { 567 bp->b_iocmd = BIO_READ; 568 vfs_busy_pages(bp, 0); 569 error = ncl_doio(vp, bp, cred, td, 0); 570 if (error) { 571 bp->b_ioflags |= BIO_ERROR; 572 brelse(bp); 573 return (error); 574 } 575 } 576 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 577 on = 0; 578 break; 579 case VDIR: 580 NFSINCRGLOBAL(nfsstatsv1.biocache_readdirs); 581 if (np->n_direofoffset 582 && uio->uio_offset >= np->n_direofoffset) { 583 return (0); 584 } 585 lbn = (uoff_t)uio->uio_offset / NFS_DIRBLKSIZ; 586 on = uio->uio_offset & (NFS_DIRBLKSIZ - 1); 587 bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, td); 588 if (!bp) { 589 error = newnfs_sigintr(nmp, td); 590 return (error ? error : EINTR); 591 } 592 if ((bp->b_flags & B_CACHE) == 0) { 593 bp->b_iocmd = BIO_READ; 594 vfs_busy_pages(bp, 0); 595 error = ncl_doio(vp, bp, cred, td, 0); 596 if (error) { 597 brelse(bp); 598 } 599 while (error == NFSERR_BAD_COOKIE) { 600 ncl_invaldir(vp); 601 error = ncl_vinvalbuf(vp, 0, td, 1); 602 603 /* 604 * Yuck! The directory has been modified on the 605 * server. The only way to get the block is by 606 * reading from the beginning to get all the 607 * offset cookies. 608 * 609 * Leave the last bp intact unless there is an error. 610 * Loop back up to the while if the error is another 611 * NFSERR_BAD_COOKIE (double yuch!). 612 */ 613 for (i = 0; i <= lbn && !error; i++) { 614 if (np->n_direofoffset 615 && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset) 616 return (0); 617 bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, td); 618 if (!bp) { 619 error = newnfs_sigintr(nmp, td); 620 return (error ? error : EINTR); 621 } 622 if ((bp->b_flags & B_CACHE) == 0) { 623 bp->b_iocmd = BIO_READ; 624 vfs_busy_pages(bp, 0); 625 error = ncl_doio(vp, bp, cred, td, 0); 626 /* 627 * no error + B_INVAL == directory EOF, 628 * use the block. 629 */ 630 if (error == 0 && (bp->b_flags & B_INVAL)) 631 break; 632 } 633 /* 634 * An error will throw away the block and the 635 * for loop will break out. If no error and this 636 * is not the block we want, we throw away the 637 * block and go for the next one via the for loop. 638 */ 639 if (error || i < lbn) 640 brelse(bp); 641 } 642 } 643 /* 644 * The above while is repeated if we hit another cookie 645 * error. If we hit an error and it wasn't a cookie error, 646 * we give up. 647 */ 648 if (error) 649 return (error); 650 } 651 652 /* 653 * If not eof and read aheads are enabled, start one. 654 * (You need the current block first, so that you have the 655 * directory offset cookie of the next block.) 656 */ 657 if (nmp->nm_readahead > 0 && 658 (bp->b_flags & B_INVAL) == 0 && 659 (np->n_direofoffset == 0 || 660 (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) && 661 incore(&vp->v_bufobj, lbn + 1) == NULL) { 662 rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td); 663 if (rabp) { 664 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 665 rabp->b_flags |= B_ASYNC; 666 rabp->b_iocmd = BIO_READ; 667 vfs_busy_pages(rabp, 0); 668 if (ncl_asyncio(nmp, rabp, cred, td)) { 669 rabp->b_flags |= B_INVAL; 670 rabp->b_ioflags |= BIO_ERROR; 671 vfs_unbusy_pages(rabp); 672 brelse(rabp); 673 } 674 } else { 675 brelse(rabp); 676 } 677 } 678 } 679 /* 680 * Unlike VREG files, whos buffer size ( bp->b_bcount ) is 681 * chopped for the EOF condition, we cannot tell how large 682 * NFS directories are going to be until we hit EOF. So 683 * an NFS directory buffer is *not* chopped to its EOF. Now, 684 * it just so happens that b_resid will effectively chop it 685 * to EOF. *BUT* this information is lost if the buffer goes 686 * away and is reconstituted into a B_CACHE state ( due to 687 * being VMIO ) later. So we keep track of the directory eof 688 * in np->n_direofoffset and chop it off as an extra step 689 * right here. 690 */ 691 n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on); 692 if (np->n_direofoffset && n > np->n_direofoffset - uio->uio_offset) 693 n = np->n_direofoffset - uio->uio_offset; 694 break; 695 default: 696 printf(" ncl_bioread: type %x unexpected\n", vp->v_type); 697 bp = NULL; 698 break; 699 } 700 701 if (n > 0) { 702 error = vn_io_fault_uiomove(bp->b_data + on, (int)n, uio); 703 } 704 if (vp->v_type == VLNK) 705 n = 0; 706 if (bp != NULL) 707 brelse(bp); 708 } while (error == 0 && uio->uio_resid > 0 && n > 0); 709 return (error); 710 } 711 712 /* 713 * The NFS write path cannot handle iovecs with len > 1. So we need to 714 * break up iovecs accordingly (restricting them to wsize). 715 * For the SYNC case, we can do this with 1 copy (user buffer -> mbuf). 716 * For the ASYNC case, 2 copies are needed. The first a copy from the 717 * user buffer to a staging buffer and then a second copy from the staging 718 * buffer to mbufs. This can be optimized by copying from the user buffer 719 * directly into mbufs and passing the chain down, but that requires a 720 * fair amount of re-working of the relevant codepaths (and can be done 721 * later). 722 */ 723 static int 724 nfs_directio_write(vp, uiop, cred, ioflag) 725 struct vnode *vp; 726 struct uio *uiop; 727 struct ucred *cred; 728 int ioflag; 729 { 730 int error; 731 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 732 struct thread *td = uiop->uio_td; 733 int size; 734 int wsize; 735 736 mtx_lock(&nmp->nm_mtx); 737 wsize = nmp->nm_wsize; 738 mtx_unlock(&nmp->nm_mtx); 739 if (ioflag & IO_SYNC) { 740 int iomode, must_commit; 741 struct uio uio; 742 struct iovec iov; 743 do_sync: 744 while (uiop->uio_resid > 0) { 745 size = MIN(uiop->uio_resid, wsize); 746 size = MIN(uiop->uio_iov->iov_len, size); 747 iov.iov_base = uiop->uio_iov->iov_base; 748 iov.iov_len = size; 749 uio.uio_iov = &iov; 750 uio.uio_iovcnt = 1; 751 uio.uio_offset = uiop->uio_offset; 752 uio.uio_resid = size; 753 uio.uio_segflg = UIO_USERSPACE; 754 uio.uio_rw = UIO_WRITE; 755 uio.uio_td = td; 756 iomode = NFSWRITE_FILESYNC; 757 error = ncl_writerpc(vp, &uio, cred, &iomode, 758 &must_commit, 0); 759 KASSERT((must_commit == 0), 760 ("ncl_directio_write: Did not commit write")); 761 if (error) 762 return (error); 763 uiop->uio_offset += size; 764 uiop->uio_resid -= size; 765 if (uiop->uio_iov->iov_len <= size) { 766 uiop->uio_iovcnt--; 767 uiop->uio_iov++; 768 } else { 769 uiop->uio_iov->iov_base = 770 (char *)uiop->uio_iov->iov_base + size; 771 uiop->uio_iov->iov_len -= size; 772 } 773 } 774 } else { 775 struct uio *t_uio; 776 struct iovec *t_iov; 777 struct buf *bp; 778 779 /* 780 * Break up the write into blocksize chunks and hand these 781 * over to nfsiod's for write back. 782 * Unfortunately, this incurs a copy of the data. Since 783 * the user could modify the buffer before the write is 784 * initiated. 785 * 786 * The obvious optimization here is that one of the 2 copies 787 * in the async write path can be eliminated by copying the 788 * data here directly into mbufs and passing the mbuf chain 789 * down. But that will require a fair amount of re-working 790 * of the code and can be done if there's enough interest 791 * in NFS directio access. 792 */ 793 while (uiop->uio_resid > 0) { 794 size = MIN(uiop->uio_resid, wsize); 795 size = MIN(uiop->uio_iov->iov_len, size); 796 bp = getpbuf(&ncl_pbuf_freecnt); 797 t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK); 798 t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK); 799 t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK); 800 t_iov->iov_len = size; 801 t_uio->uio_iov = t_iov; 802 t_uio->uio_iovcnt = 1; 803 t_uio->uio_offset = uiop->uio_offset; 804 t_uio->uio_resid = size; 805 t_uio->uio_segflg = UIO_SYSSPACE; 806 t_uio->uio_rw = UIO_WRITE; 807 t_uio->uio_td = td; 808 KASSERT(uiop->uio_segflg == UIO_USERSPACE || 809 uiop->uio_segflg == UIO_SYSSPACE, 810 ("nfs_directio_write: Bad uio_segflg")); 811 if (uiop->uio_segflg == UIO_USERSPACE) { 812 error = copyin(uiop->uio_iov->iov_base, 813 t_iov->iov_base, size); 814 if (error != 0) 815 goto err_free; 816 } else 817 /* 818 * UIO_SYSSPACE may never happen, but handle 819 * it just in case it does. 820 */ 821 bcopy(uiop->uio_iov->iov_base, t_iov->iov_base, 822 size); 823 bp->b_flags |= B_DIRECT; 824 bp->b_iocmd = BIO_WRITE; 825 if (cred != NOCRED) { 826 crhold(cred); 827 bp->b_wcred = cred; 828 } else 829 bp->b_wcred = NOCRED; 830 bp->b_caller1 = (void *)t_uio; 831 bp->b_vp = vp; 832 error = ncl_asyncio(nmp, bp, NOCRED, td); 833 err_free: 834 if (error) { 835 free(t_iov->iov_base, M_NFSDIRECTIO); 836 free(t_iov, M_NFSDIRECTIO); 837 free(t_uio, M_NFSDIRECTIO); 838 bp->b_vp = NULL; 839 relpbuf(bp, &ncl_pbuf_freecnt); 840 if (error == EINTR) 841 return (error); 842 goto do_sync; 843 } 844 uiop->uio_offset += size; 845 uiop->uio_resid -= size; 846 if (uiop->uio_iov->iov_len <= size) { 847 uiop->uio_iovcnt--; 848 uiop->uio_iov++; 849 } else { 850 uiop->uio_iov->iov_base = 851 (char *)uiop->uio_iov->iov_base + size; 852 uiop->uio_iov->iov_len -= size; 853 } 854 } 855 } 856 return (0); 857 } 858 859 /* 860 * Vnode op for write using bio 861 */ 862 int 863 ncl_write(struct vop_write_args *ap) 864 { 865 int biosize; 866 struct uio *uio = ap->a_uio; 867 struct thread *td = uio->uio_td; 868 struct vnode *vp = ap->a_vp; 869 struct nfsnode *np = VTONFS(vp); 870 struct ucred *cred = ap->a_cred; 871 int ioflag = ap->a_ioflag; 872 struct buf *bp; 873 struct vattr vattr; 874 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 875 daddr_t lbn; 876 int bcount, noncontig_write, obcount; 877 int bp_cached, n, on, error = 0, error1, wouldcommit; 878 size_t orig_resid, local_resid; 879 off_t orig_size, tmp_off; 880 881 KASSERT(uio->uio_rw == UIO_WRITE, ("ncl_write mode")); 882 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 883 ("ncl_write proc")); 884 if (vp->v_type != VREG) 885 return (EIO); 886 mtx_lock(&np->n_mtx); 887 if (np->n_flag & NWRITEERR) { 888 np->n_flag &= ~NWRITEERR; 889 mtx_unlock(&np->n_mtx); 890 return (np->n_error); 891 } else 892 mtx_unlock(&np->n_mtx); 893 mtx_lock(&nmp->nm_mtx); 894 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 895 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 896 mtx_unlock(&nmp->nm_mtx); 897 (void)ncl_fsinfo(nmp, vp, cred, td); 898 mtx_lock(&nmp->nm_mtx); 899 } 900 if (nmp->nm_wsize == 0) 901 (void) newnfs_iosize(nmp); 902 mtx_unlock(&nmp->nm_mtx); 903 904 /* 905 * Synchronously flush pending buffers if we are in synchronous 906 * mode or if we are appending. 907 */ 908 if (ioflag & (IO_APPEND | IO_SYNC)) { 909 mtx_lock(&np->n_mtx); 910 if (np->n_flag & NMODIFIED) { 911 mtx_unlock(&np->n_mtx); 912 #ifdef notyet /* Needs matching nonblock semantics elsewhere, too. */ 913 /* 914 * Require non-blocking, synchronous writes to 915 * dirty files to inform the program it needs 916 * to fsync(2) explicitly. 917 */ 918 if (ioflag & IO_NDELAY) 919 return (EAGAIN); 920 #endif 921 np->n_attrstamp = 0; 922 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 923 error = ncl_vinvalbuf(vp, V_SAVE | ((ioflag & 924 IO_VMIO) != 0 ? V_VMIO : 0), td, 1); 925 if (error != 0) 926 return (error); 927 } else 928 mtx_unlock(&np->n_mtx); 929 } 930 931 orig_resid = uio->uio_resid; 932 mtx_lock(&np->n_mtx); 933 orig_size = np->n_size; 934 mtx_unlock(&np->n_mtx); 935 936 /* 937 * If IO_APPEND then load uio_offset. We restart here if we cannot 938 * get the append lock. 939 */ 940 if (ioflag & IO_APPEND) { 941 np->n_attrstamp = 0; 942 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 943 error = VOP_GETATTR(vp, &vattr, cred); 944 if (error) 945 return (error); 946 mtx_lock(&np->n_mtx); 947 uio->uio_offset = np->n_size; 948 mtx_unlock(&np->n_mtx); 949 } 950 951 if (uio->uio_offset < 0) 952 return (EINVAL); 953 tmp_off = uio->uio_offset + uio->uio_resid; 954 if (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset) 955 return (EFBIG); 956 if (uio->uio_resid == 0) 957 return (0); 958 959 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && vp->v_type == VREG) 960 return nfs_directio_write(vp, uio, cred, ioflag); 961 962 /* 963 * Maybe this should be above the vnode op call, but so long as 964 * file servers have no limits, i don't think it matters 965 */ 966 if (vn_rlimit_fsize(vp, uio, td)) 967 return (EFBIG); 968 969 biosize = vp->v_bufobj.bo_bsize; 970 /* 971 * Find all of this file's B_NEEDCOMMIT buffers. If our writes 972 * would exceed the local maximum per-file write commit size when 973 * combined with those, we must decide whether to flush, 974 * go synchronous, or return error. We don't bother checking 975 * IO_UNIT -- we just make all writes atomic anyway, as there's 976 * no point optimizing for something that really won't ever happen. 977 */ 978 wouldcommit = 0; 979 if (!(ioflag & IO_SYNC)) { 980 int nflag; 981 982 mtx_lock(&np->n_mtx); 983 nflag = np->n_flag; 984 mtx_unlock(&np->n_mtx); 985 if (nflag & NMODIFIED) { 986 BO_LOCK(&vp->v_bufobj); 987 if (vp->v_bufobj.bo_dirty.bv_cnt != 0) { 988 TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd, 989 b_bobufs) { 990 if (bp->b_flags & B_NEEDCOMMIT) 991 wouldcommit += bp->b_bcount; 992 } 993 } 994 BO_UNLOCK(&vp->v_bufobj); 995 } 996 } 997 998 do { 999 if (!(ioflag & IO_SYNC)) { 1000 wouldcommit += biosize; 1001 if (wouldcommit > nmp->nm_wcommitsize) { 1002 np->n_attrstamp = 0; 1003 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 1004 error = ncl_vinvalbuf(vp, V_SAVE | ((ioflag & 1005 IO_VMIO) != 0 ? V_VMIO : 0), td, 1); 1006 if (error != 0) 1007 return (error); 1008 wouldcommit = biosize; 1009 } 1010 } 1011 1012 NFSINCRGLOBAL(nfsstatsv1.biocache_writes); 1013 lbn = uio->uio_offset / biosize; 1014 on = uio->uio_offset - (lbn * biosize); 1015 n = MIN((unsigned)(biosize - on), uio->uio_resid); 1016 again: 1017 /* 1018 * Handle direct append and file extension cases, calculate 1019 * unaligned buffer size. 1020 */ 1021 mtx_lock(&np->n_mtx); 1022 if ((np->n_flag & NHASBEENLOCKED) == 0 && 1023 (nmp->nm_flag & NFSMNT_NONCONTIGWR) != 0) 1024 noncontig_write = 1; 1025 else 1026 noncontig_write = 0; 1027 if ((uio->uio_offset == np->n_size || 1028 (noncontig_write != 0 && 1029 lbn == (np->n_size / biosize) && 1030 uio->uio_offset + n > np->n_size)) && n) { 1031 mtx_unlock(&np->n_mtx); 1032 /* 1033 * Get the buffer (in its pre-append state to maintain 1034 * B_CACHE if it was previously set). Resize the 1035 * nfsnode after we have locked the buffer to prevent 1036 * readers from reading garbage. 1037 */ 1038 obcount = np->n_size - (lbn * biosize); 1039 bp = nfs_getcacheblk(vp, lbn, obcount, td); 1040 1041 if (bp != NULL) { 1042 long save; 1043 1044 mtx_lock(&np->n_mtx); 1045 np->n_size = uio->uio_offset + n; 1046 np->n_flag |= NMODIFIED; 1047 vnode_pager_setsize(vp, np->n_size); 1048 mtx_unlock(&np->n_mtx); 1049 1050 save = bp->b_flags & B_CACHE; 1051 bcount = on + n; 1052 allocbuf(bp, bcount); 1053 bp->b_flags |= save; 1054 if (noncontig_write != 0 && on > obcount) 1055 vfs_bio_bzero_buf(bp, obcount, on - 1056 obcount); 1057 } 1058 } else { 1059 /* 1060 * Obtain the locked cache block first, and then 1061 * adjust the file's size as appropriate. 1062 */ 1063 bcount = on + n; 1064 if ((off_t)lbn * biosize + bcount < np->n_size) { 1065 if ((off_t)(lbn + 1) * biosize < np->n_size) 1066 bcount = biosize; 1067 else 1068 bcount = np->n_size - (off_t)lbn * biosize; 1069 } 1070 mtx_unlock(&np->n_mtx); 1071 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1072 mtx_lock(&np->n_mtx); 1073 if (uio->uio_offset + n > np->n_size) { 1074 np->n_size = uio->uio_offset + n; 1075 np->n_flag |= NMODIFIED; 1076 vnode_pager_setsize(vp, np->n_size); 1077 } 1078 mtx_unlock(&np->n_mtx); 1079 } 1080 1081 if (!bp) { 1082 error = newnfs_sigintr(nmp, td); 1083 if (!error) 1084 error = EINTR; 1085 break; 1086 } 1087 1088 /* 1089 * Issue a READ if B_CACHE is not set. In special-append 1090 * mode, B_CACHE is based on the buffer prior to the write 1091 * op and is typically set, avoiding the read. If a read 1092 * is required in special append mode, the server will 1093 * probably send us a short-read since we extended the file 1094 * on our end, resulting in b_resid == 0 and, thusly, 1095 * B_CACHE getting set. 1096 * 1097 * We can also avoid issuing the read if the write covers 1098 * the entire buffer. We have to make sure the buffer state 1099 * is reasonable in this case since we will not be initiating 1100 * I/O. See the comments in kern/vfs_bio.c's getblk() for 1101 * more information. 1102 * 1103 * B_CACHE may also be set due to the buffer being cached 1104 * normally. 1105 */ 1106 1107 bp_cached = 1; 1108 if (on == 0 && n == bcount) { 1109 if ((bp->b_flags & B_CACHE) == 0) 1110 bp_cached = 0; 1111 bp->b_flags |= B_CACHE; 1112 bp->b_flags &= ~B_INVAL; 1113 bp->b_ioflags &= ~BIO_ERROR; 1114 } 1115 1116 if ((bp->b_flags & B_CACHE) == 0) { 1117 bp->b_iocmd = BIO_READ; 1118 vfs_busy_pages(bp, 0); 1119 error = ncl_doio(vp, bp, cred, td, 0); 1120 if (error) { 1121 brelse(bp); 1122 break; 1123 } 1124 } 1125 if (bp->b_wcred == NOCRED) 1126 bp->b_wcred = crhold(cred); 1127 mtx_lock(&np->n_mtx); 1128 np->n_flag |= NMODIFIED; 1129 mtx_unlock(&np->n_mtx); 1130 1131 /* 1132 * If dirtyend exceeds file size, chop it down. This should 1133 * not normally occur but there is an append race where it 1134 * might occur XXX, so we log it. 1135 * 1136 * If the chopping creates a reverse-indexed or degenerate 1137 * situation with dirtyoff/end, we 0 both of them. 1138 */ 1139 1140 if (bp->b_dirtyend > bcount) { 1141 printf("NFS append race @%lx:%d\n", 1142 (long)bp->b_blkno * DEV_BSIZE, 1143 bp->b_dirtyend - bcount); 1144 bp->b_dirtyend = bcount; 1145 } 1146 1147 if (bp->b_dirtyoff >= bp->b_dirtyend) 1148 bp->b_dirtyoff = bp->b_dirtyend = 0; 1149 1150 /* 1151 * If the new write will leave a contiguous dirty 1152 * area, just update the b_dirtyoff and b_dirtyend, 1153 * otherwise force a write rpc of the old dirty area. 1154 * 1155 * If there has been a file lock applied to this file 1156 * or vfs.nfs.old_noncontig_writing is set, do the following: 1157 * While it is possible to merge discontiguous writes due to 1158 * our having a B_CACHE buffer ( and thus valid read data 1159 * for the hole), we don't because it could lead to 1160 * significant cache coherency problems with multiple clients, 1161 * especially if locking is implemented later on. 1162 * 1163 * If vfs.nfs.old_noncontig_writing is not set and there has 1164 * not been file locking done on this file: 1165 * Relax coherency a bit for the sake of performance and 1166 * expand the current dirty region to contain the new 1167 * write even if it means we mark some non-dirty data as 1168 * dirty. 1169 */ 1170 1171 if (noncontig_write == 0 && bp->b_dirtyend > 0 && 1172 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 1173 if (bwrite(bp) == EINTR) { 1174 error = EINTR; 1175 break; 1176 } 1177 goto again; 1178 } 1179 1180 local_resid = uio->uio_resid; 1181 error = vn_io_fault_uiomove((char *)bp->b_data + on, n, uio); 1182 1183 if (error != 0 && !bp_cached) { 1184 /* 1185 * This block has no other content then what 1186 * possibly was written by the faulty uiomove. 1187 * Release it, forgetting the data pages, to 1188 * prevent the leak of uninitialized data to 1189 * usermode. 1190 */ 1191 bp->b_ioflags |= BIO_ERROR; 1192 brelse(bp); 1193 uio->uio_offset -= local_resid - uio->uio_resid; 1194 uio->uio_resid = local_resid; 1195 break; 1196 } 1197 1198 /* 1199 * Since this block is being modified, it must be written 1200 * again and not just committed. Since write clustering does 1201 * not work for the stage 1 data write, only the stage 2 1202 * commit rpc, we have to clear B_CLUSTEROK as well. 1203 */ 1204 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1205 1206 /* 1207 * Get the partial update on the progress made from 1208 * uiomove, if an error occurred. 1209 */ 1210 if (error != 0) 1211 n = local_resid - uio->uio_resid; 1212 1213 /* 1214 * Only update dirtyoff/dirtyend if not a degenerate 1215 * condition. 1216 */ 1217 if (n > 0) { 1218 if (bp->b_dirtyend > 0) { 1219 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 1220 bp->b_dirtyend = max((on + n), bp->b_dirtyend); 1221 } else { 1222 bp->b_dirtyoff = on; 1223 bp->b_dirtyend = on + n; 1224 } 1225 vfs_bio_set_valid(bp, on, n); 1226 } 1227 1228 /* 1229 * If IO_SYNC do bwrite(). 1230 * 1231 * IO_INVAL appears to be unused. The idea appears to be 1232 * to turn off caching in this case. Very odd. XXX 1233 */ 1234 if ((ioflag & IO_SYNC)) { 1235 if (ioflag & IO_INVAL) 1236 bp->b_flags |= B_NOCACHE; 1237 error1 = bwrite(bp); 1238 if (error1 != 0) { 1239 if (error == 0) 1240 error = error1; 1241 break; 1242 } 1243 } else if ((n + on) == biosize || (ioflag & IO_ASYNC) != 0) { 1244 bp->b_flags |= B_ASYNC; 1245 (void) ncl_writebp(bp, 0, NULL); 1246 } else { 1247 bdwrite(bp); 1248 } 1249 1250 if (error != 0) 1251 break; 1252 } while (uio->uio_resid > 0 && n > 0); 1253 1254 if (error != 0) { 1255 if (ioflag & IO_UNIT) { 1256 VATTR_NULL(&vattr); 1257 vattr.va_size = orig_size; 1258 /* IO_SYNC is handled implicitely */ 1259 (void)VOP_SETATTR(vp, &vattr, cred); 1260 uio->uio_offset -= orig_resid - uio->uio_resid; 1261 uio->uio_resid = orig_resid; 1262 } 1263 } 1264 1265 return (error); 1266 } 1267 1268 /* 1269 * Get an nfs cache block. 1270 * 1271 * Allocate a new one if the block isn't currently in the cache 1272 * and return the block marked busy. If the calling process is 1273 * interrupted by a signal for an interruptible mount point, return 1274 * NULL. 1275 * 1276 * The caller must carefully deal with the possible B_INVAL state of 1277 * the buffer. ncl_doio() clears B_INVAL (and ncl_asyncio() clears it 1278 * indirectly), so synchronous reads can be issued without worrying about 1279 * the B_INVAL state. We have to be a little more careful when dealing 1280 * with writes (see comments in nfs_write()) when extending a file past 1281 * its EOF. 1282 */ 1283 static struct buf * 1284 nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td) 1285 { 1286 struct buf *bp; 1287 struct mount *mp; 1288 struct nfsmount *nmp; 1289 1290 mp = vp->v_mount; 1291 nmp = VFSTONFS(mp); 1292 1293 if (nmp->nm_flag & NFSMNT_INT) { 1294 sigset_t oldset; 1295 1296 newnfs_set_sigmask(td, &oldset); 1297 bp = getblk(vp, bn, size, PCATCH, 0, 0); 1298 newnfs_restore_sigmask(td, &oldset); 1299 while (bp == NULL) { 1300 if (newnfs_sigintr(nmp, td)) 1301 return (NULL); 1302 bp = getblk(vp, bn, size, 0, 2 * hz, 0); 1303 } 1304 } else { 1305 bp = getblk(vp, bn, size, 0, 0, 0); 1306 } 1307 1308 if (vp->v_type == VREG) 1309 bp->b_blkno = bn * (vp->v_bufobj.bo_bsize / DEV_BSIZE); 1310 return (bp); 1311 } 1312 1313 /* 1314 * Flush and invalidate all dirty buffers. If another process is already 1315 * doing the flush, just wait for completion. 1316 */ 1317 int 1318 ncl_vinvalbuf(struct vnode *vp, int flags, struct thread *td, int intrflg) 1319 { 1320 struct nfsnode *np = VTONFS(vp); 1321 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1322 int error = 0, slpflag, slptimeo; 1323 bool old_lock; 1324 1325 ASSERT_VOP_LOCKED(vp, "ncl_vinvalbuf"); 1326 1327 if ((nmp->nm_flag & NFSMNT_INT) == 0) 1328 intrflg = 0; 1329 if (NFSCL_FORCEDISM(nmp->nm_mountp)) 1330 intrflg = 1; 1331 if (intrflg) { 1332 slpflag = PCATCH; 1333 slptimeo = 2 * hz; 1334 } else { 1335 slpflag = 0; 1336 slptimeo = 0; 1337 } 1338 1339 old_lock = ncl_excl_start(vp); 1340 if (old_lock) 1341 flags |= V_ALLOWCLEAN; 1342 1343 /* 1344 * Now, flush as required. 1345 */ 1346 if ((flags & (V_SAVE | V_VMIO)) == V_SAVE && 1347 vp->v_bufobj.bo_object != NULL) { 1348 VM_OBJECT_WLOCK(vp->v_bufobj.bo_object); 1349 vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC); 1350 VM_OBJECT_WUNLOCK(vp->v_bufobj.bo_object); 1351 /* 1352 * If the page clean was interrupted, fail the invalidation. 1353 * Not doing so, we run the risk of losing dirty pages in the 1354 * vinvalbuf() call below. 1355 */ 1356 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1357 goto out; 1358 } 1359 1360 error = vinvalbuf(vp, flags, slpflag, 0); 1361 while (error) { 1362 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1363 goto out; 1364 error = vinvalbuf(vp, flags, 0, slptimeo); 1365 } 1366 if (NFSHASPNFS(nmp)) { 1367 nfscl_layoutcommit(vp, td); 1368 /* 1369 * Invalidate the attribute cache, since writes to a DS 1370 * won't update the size attribute. 1371 */ 1372 mtx_lock(&np->n_mtx); 1373 np->n_attrstamp = 0; 1374 } else 1375 mtx_lock(&np->n_mtx); 1376 if (np->n_directio_asyncwr == 0) 1377 np->n_flag &= ~NMODIFIED; 1378 mtx_unlock(&np->n_mtx); 1379 out: 1380 ncl_excl_finish(vp, old_lock); 1381 return error; 1382 } 1383 1384 /* 1385 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 1386 * This is mainly to avoid queueing async I/O requests when the nfsiods 1387 * are all hung on a dead server. 1388 * 1389 * Note: ncl_asyncio() does not clear (BIO_ERROR|B_INVAL) but when the bp 1390 * is eventually dequeued by the async daemon, ncl_doio() *will*. 1391 */ 1392 int 1393 ncl_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td) 1394 { 1395 int iod; 1396 int gotiod; 1397 int slpflag = 0; 1398 int slptimeo = 0; 1399 int error, error2; 1400 1401 /* 1402 * Commits are usually short and sweet so lets save some cpu and 1403 * leave the async daemons for more important rpc's (such as reads 1404 * and writes). 1405 * 1406 * Readdirplus RPCs do vget()s to acquire the vnodes for entries 1407 * in the directory in order to update attributes. This can deadlock 1408 * with another thread that is waiting for async I/O to be done by 1409 * an nfsiod thread while holding a lock on one of these vnodes. 1410 * To avoid this deadlock, don't allow the async nfsiod threads to 1411 * perform Readdirplus RPCs. 1412 */ 1413 mtx_lock(&ncl_iod_mutex); 1414 if ((bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) && 1415 (nmp->nm_bufqiods > ncl_numasync / 2)) || 1416 (bp->b_vp->v_type == VDIR && (nmp->nm_flag & NFSMNT_RDIRPLUS))) { 1417 mtx_unlock(&ncl_iod_mutex); 1418 return(EIO); 1419 } 1420 again: 1421 if (nmp->nm_flag & NFSMNT_INT) 1422 slpflag = PCATCH; 1423 gotiod = FALSE; 1424 1425 /* 1426 * Find a free iod to process this request. 1427 */ 1428 for (iod = 0; iod < ncl_numasync; iod++) 1429 if (ncl_iodwant[iod] == NFSIOD_AVAILABLE) { 1430 gotiod = TRUE; 1431 break; 1432 } 1433 1434 /* 1435 * Try to create one if none are free. 1436 */ 1437 if (!gotiod) 1438 ncl_nfsiodnew(); 1439 else { 1440 /* 1441 * Found one, so wake it up and tell it which 1442 * mount to process. 1443 */ 1444 NFS_DPF(ASYNCIO, ("ncl_asyncio: waking iod %d for mount %p\n", 1445 iod, nmp)); 1446 ncl_iodwant[iod] = NFSIOD_NOT_AVAILABLE; 1447 ncl_iodmount[iod] = nmp; 1448 nmp->nm_bufqiods++; 1449 wakeup(&ncl_iodwant[iod]); 1450 } 1451 1452 /* 1453 * If none are free, we may already have an iod working on this mount 1454 * point. If so, it will process our request. 1455 */ 1456 if (!gotiod) { 1457 if (nmp->nm_bufqiods > 0) { 1458 NFS_DPF(ASYNCIO, 1459 ("ncl_asyncio: %d iods are already processing mount %p\n", 1460 nmp->nm_bufqiods, nmp)); 1461 gotiod = TRUE; 1462 } 1463 } 1464 1465 /* 1466 * If we have an iod which can process the request, then queue 1467 * the buffer. 1468 */ 1469 if (gotiod) { 1470 /* 1471 * Ensure that the queue never grows too large. We still want 1472 * to asynchronize so we block rather then return EIO. 1473 */ 1474 while (nmp->nm_bufqlen >= 2*ncl_numasync) { 1475 NFS_DPF(ASYNCIO, 1476 ("ncl_asyncio: waiting for mount %p queue to drain\n", nmp)); 1477 nmp->nm_bufqwant = TRUE; 1478 error = newnfs_msleep(td, &nmp->nm_bufq, 1479 &ncl_iod_mutex, slpflag | PRIBIO, "nfsaio", 1480 slptimeo); 1481 if (error) { 1482 error2 = newnfs_sigintr(nmp, td); 1483 if (error2) { 1484 mtx_unlock(&ncl_iod_mutex); 1485 return (error2); 1486 } 1487 if (slpflag == PCATCH) { 1488 slpflag = 0; 1489 slptimeo = 2 * hz; 1490 } 1491 } 1492 /* 1493 * We might have lost our iod while sleeping, 1494 * so check and loop if necessary. 1495 */ 1496 goto again; 1497 } 1498 1499 /* We might have lost our nfsiod */ 1500 if (nmp->nm_bufqiods == 0) { 1501 NFS_DPF(ASYNCIO, 1502 ("ncl_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); 1503 goto again; 1504 } 1505 1506 if (bp->b_iocmd == BIO_READ) { 1507 if (bp->b_rcred == NOCRED && cred != NOCRED) 1508 bp->b_rcred = crhold(cred); 1509 } else { 1510 if (bp->b_wcred == NOCRED && cred != NOCRED) 1511 bp->b_wcred = crhold(cred); 1512 } 1513 1514 if (bp->b_flags & B_REMFREE) 1515 bremfreef(bp); 1516 BUF_KERNPROC(bp); 1517 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 1518 nmp->nm_bufqlen++; 1519 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1520 mtx_lock(&(VTONFS(bp->b_vp))->n_mtx); 1521 VTONFS(bp->b_vp)->n_flag |= NMODIFIED; 1522 VTONFS(bp->b_vp)->n_directio_asyncwr++; 1523 mtx_unlock(&(VTONFS(bp->b_vp))->n_mtx); 1524 } 1525 mtx_unlock(&ncl_iod_mutex); 1526 return (0); 1527 } 1528 1529 mtx_unlock(&ncl_iod_mutex); 1530 1531 /* 1532 * All the iods are busy on other mounts, so return EIO to 1533 * force the caller to process the i/o synchronously. 1534 */ 1535 NFS_DPF(ASYNCIO, ("ncl_asyncio: no iods available, i/o is synchronous\n")); 1536 return (EIO); 1537 } 1538 1539 void 1540 ncl_doio_directwrite(struct buf *bp) 1541 { 1542 int iomode, must_commit; 1543 struct uio *uiop = (struct uio *)bp->b_caller1; 1544 char *iov_base = uiop->uio_iov->iov_base; 1545 1546 iomode = NFSWRITE_FILESYNC; 1547 uiop->uio_td = NULL; /* NULL since we're in nfsiod */ 1548 ncl_writerpc(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit, 0); 1549 KASSERT((must_commit == 0), ("ncl_doio_directwrite: Did not commit write")); 1550 free(iov_base, M_NFSDIRECTIO); 1551 free(uiop->uio_iov, M_NFSDIRECTIO); 1552 free(uiop, M_NFSDIRECTIO); 1553 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1554 struct nfsnode *np = VTONFS(bp->b_vp); 1555 mtx_lock(&np->n_mtx); 1556 if (NFSHASPNFS(VFSTONFS(vnode_mount(bp->b_vp)))) { 1557 /* 1558 * Invalidate the attribute cache, since writes to a DS 1559 * won't update the size attribute. 1560 */ 1561 np->n_attrstamp = 0; 1562 } 1563 np->n_directio_asyncwr--; 1564 if (np->n_directio_asyncwr == 0) { 1565 np->n_flag &= ~NMODIFIED; 1566 if ((np->n_flag & NFSYNCWAIT)) { 1567 np->n_flag &= ~NFSYNCWAIT; 1568 wakeup((caddr_t)&np->n_directio_asyncwr); 1569 } 1570 } 1571 mtx_unlock(&np->n_mtx); 1572 } 1573 bp->b_vp = NULL; 1574 relpbuf(bp, &ncl_pbuf_freecnt); 1575 } 1576 1577 /* 1578 * Do an I/O operation to/from a cache block. This may be called 1579 * synchronously or from an nfsiod. 1580 */ 1581 int 1582 ncl_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td, 1583 int called_from_strategy) 1584 { 1585 struct uio *uiop; 1586 struct nfsnode *np; 1587 struct nfsmount *nmp; 1588 int error = 0, iomode, must_commit = 0; 1589 struct uio uio; 1590 struct iovec io; 1591 struct proc *p = td ? td->td_proc : NULL; 1592 uint8_t iocmd; 1593 1594 np = VTONFS(vp); 1595 nmp = VFSTONFS(vp->v_mount); 1596 uiop = &uio; 1597 uiop->uio_iov = &io; 1598 uiop->uio_iovcnt = 1; 1599 uiop->uio_segflg = UIO_SYSSPACE; 1600 uiop->uio_td = td; 1601 1602 /* 1603 * clear BIO_ERROR and B_INVAL state prior to initiating the I/O. We 1604 * do this here so we do not have to do it in all the code that 1605 * calls us. 1606 */ 1607 bp->b_flags &= ~B_INVAL; 1608 bp->b_ioflags &= ~BIO_ERROR; 1609 1610 KASSERT(!(bp->b_flags & B_DONE), ("ncl_doio: bp %p already marked done", bp)); 1611 iocmd = bp->b_iocmd; 1612 if (iocmd == BIO_READ) { 1613 io.iov_len = uiop->uio_resid = bp->b_bcount; 1614 io.iov_base = bp->b_data; 1615 uiop->uio_rw = UIO_READ; 1616 1617 switch (vp->v_type) { 1618 case VREG: 1619 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1620 NFSINCRGLOBAL(nfsstatsv1.read_bios); 1621 error = ncl_readrpc(vp, uiop, cr); 1622 1623 if (!error) { 1624 if (uiop->uio_resid) { 1625 /* 1626 * If we had a short read with no error, we must have 1627 * hit a file hole. We should zero-fill the remainder. 1628 * This can also occur if the server hits the file EOF. 1629 * 1630 * Holes used to be able to occur due to pending 1631 * writes, but that is not possible any longer. 1632 */ 1633 int nread = bp->b_bcount - uiop->uio_resid; 1634 ssize_t left = uiop->uio_resid; 1635 1636 if (left > 0) 1637 bzero((char *)bp->b_data + nread, left); 1638 uiop->uio_resid = 0; 1639 } 1640 } 1641 /* ASSERT_VOP_LOCKED(vp, "ncl_doio"); */ 1642 if (p && (vp->v_vflag & VV_TEXT)) { 1643 mtx_lock(&np->n_mtx); 1644 if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.na_mtime)) { 1645 mtx_unlock(&np->n_mtx); 1646 PROC_LOCK(p); 1647 killproc(p, "text file modification"); 1648 PROC_UNLOCK(p); 1649 } else 1650 mtx_unlock(&np->n_mtx); 1651 } 1652 break; 1653 case VLNK: 1654 uiop->uio_offset = (off_t)0; 1655 NFSINCRGLOBAL(nfsstatsv1.readlink_bios); 1656 error = ncl_readlinkrpc(vp, uiop, cr); 1657 break; 1658 case VDIR: 1659 NFSINCRGLOBAL(nfsstatsv1.readdir_bios); 1660 uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ; 1661 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) != 0) { 1662 error = ncl_readdirplusrpc(vp, uiop, cr, td); 1663 if (error == NFSERR_NOTSUPP) 1664 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 1665 } 1666 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 1667 error = ncl_readdirrpc(vp, uiop, cr, td); 1668 /* 1669 * end-of-directory sets B_INVAL but does not generate an 1670 * error. 1671 */ 1672 if (error == 0 && uiop->uio_resid == bp->b_bcount) 1673 bp->b_flags |= B_INVAL; 1674 break; 1675 default: 1676 printf("ncl_doio: type %x unexpected\n", vp->v_type); 1677 break; 1678 } 1679 if (error) { 1680 bp->b_ioflags |= BIO_ERROR; 1681 bp->b_error = error; 1682 } 1683 } else { 1684 /* 1685 * If we only need to commit, try to commit 1686 */ 1687 if (bp->b_flags & B_NEEDCOMMIT) { 1688 int retv; 1689 off_t off; 1690 1691 off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff; 1692 retv = ncl_commit(vp, off, bp->b_dirtyend-bp->b_dirtyoff, 1693 bp->b_wcred, td); 1694 if (retv == 0) { 1695 bp->b_dirtyoff = bp->b_dirtyend = 0; 1696 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1697 bp->b_resid = 0; 1698 bufdone(bp); 1699 return (0); 1700 } 1701 if (retv == NFSERR_STALEWRITEVERF) { 1702 ncl_clearcommit(vp->v_mount); 1703 } 1704 } 1705 1706 /* 1707 * Setup for actual write 1708 */ 1709 mtx_lock(&np->n_mtx); 1710 if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size) 1711 bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE; 1712 mtx_unlock(&np->n_mtx); 1713 1714 if (bp->b_dirtyend > bp->b_dirtyoff) { 1715 io.iov_len = uiop->uio_resid = bp->b_dirtyend 1716 - bp->b_dirtyoff; 1717 uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE 1718 + bp->b_dirtyoff; 1719 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 1720 uiop->uio_rw = UIO_WRITE; 1721 NFSINCRGLOBAL(nfsstatsv1.write_bios); 1722 1723 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC) 1724 iomode = NFSWRITE_UNSTABLE; 1725 else 1726 iomode = NFSWRITE_FILESYNC; 1727 1728 error = ncl_writerpc(vp, uiop, cr, &iomode, &must_commit, 1729 called_from_strategy); 1730 1731 /* 1732 * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try 1733 * to cluster the buffers needing commit. This will allow 1734 * the system to submit a single commit rpc for the whole 1735 * cluster. We can do this even if the buffer is not 100% 1736 * dirty (relative to the NFS blocksize), so we optimize the 1737 * append-to-file-case. 1738 * 1739 * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be 1740 * cleared because write clustering only works for commit 1741 * rpc's, not for the data portion of the write). 1742 */ 1743 1744 if (!error && iomode == NFSWRITE_UNSTABLE) { 1745 bp->b_flags |= B_NEEDCOMMIT; 1746 if (bp->b_dirtyoff == 0 1747 && bp->b_dirtyend == bp->b_bcount) 1748 bp->b_flags |= B_CLUSTEROK; 1749 } else { 1750 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1751 } 1752 1753 /* 1754 * For an interrupted write, the buffer is still valid 1755 * and the write hasn't been pushed to the server yet, 1756 * so we can't set BIO_ERROR and report the interruption 1757 * by setting B_EINTR. For the B_ASYNC case, B_EINTR 1758 * is not relevant, so the rpc attempt is essentially 1759 * a noop. For the case of a V3 write rpc not being 1760 * committed to stable storage, the block is still 1761 * dirty and requires either a commit rpc or another 1762 * write rpc with iomode == NFSV3WRITE_FILESYNC before 1763 * the block is reused. This is indicated by setting 1764 * the B_DELWRI and B_NEEDCOMMIT flags. 1765 * 1766 * EIO is returned by ncl_writerpc() to indicate a recoverable 1767 * write error and is handled as above, except that 1768 * B_EINTR isn't set. One cause of this is a stale stateid 1769 * error for the RPC that indicates recovery is required, 1770 * when called with called_from_strategy != 0. 1771 * 1772 * If the buffer is marked B_PAGING, it does not reside on 1773 * the vp's paging queues so we cannot call bdirty(). The 1774 * bp in this case is not an NFS cache block so we should 1775 * be safe. XXX 1776 * 1777 * The logic below breaks up errors into recoverable and 1778 * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE 1779 * and keep the buffer around for potential write retries. 1780 * For the latter (eg ESTALE), we toss the buffer away (B_INVAL) 1781 * and save the error in the nfsnode. This is less than ideal 1782 * but necessary. Keeping such buffers around could potentially 1783 * cause buffer exhaustion eventually (they can never be written 1784 * out, so will get constantly be re-dirtied). It also causes 1785 * all sorts of vfs panics. For non-recoverable write errors, 1786 * also invalidate the attrcache, so we'll be forced to go over 1787 * the wire for this object, returning an error to user on next 1788 * call (most of the time). 1789 */ 1790 if (error == EINTR || error == EIO || error == ETIMEDOUT 1791 || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 1792 bp->b_flags &= ~(B_INVAL|B_NOCACHE); 1793 if ((bp->b_flags & B_PAGING) == 0) { 1794 bdirty(bp); 1795 bp->b_flags &= ~B_DONE; 1796 } 1797 if ((error == EINTR || error == ETIMEDOUT) && 1798 (bp->b_flags & B_ASYNC) == 0) 1799 bp->b_flags |= B_EINTR; 1800 } else { 1801 if (error) { 1802 bp->b_ioflags |= BIO_ERROR; 1803 bp->b_flags |= B_INVAL; 1804 bp->b_error = np->n_error = error; 1805 mtx_lock(&np->n_mtx); 1806 np->n_flag |= NWRITEERR; 1807 np->n_attrstamp = 0; 1808 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 1809 mtx_unlock(&np->n_mtx); 1810 } 1811 bp->b_dirtyoff = bp->b_dirtyend = 0; 1812 } 1813 } else { 1814 bp->b_resid = 0; 1815 bufdone(bp); 1816 return (0); 1817 } 1818 } 1819 bp->b_resid = uiop->uio_resid; 1820 if (must_commit) 1821 ncl_clearcommit(vp->v_mount); 1822 bufdone(bp); 1823 return (error); 1824 } 1825 1826 /* 1827 * Used to aid in handling ftruncate() operations on the NFS client side. 1828 * Truncation creates a number of special problems for NFS. We have to 1829 * throw away VM pages and buffer cache buffers that are beyond EOF, and 1830 * we have to properly handle VM pages or (potentially dirty) buffers 1831 * that straddle the truncation point. 1832 */ 1833 1834 int 1835 ncl_meta_setsize(struct vnode *vp, struct ucred *cred, struct thread *td, u_quad_t nsize) 1836 { 1837 struct nfsnode *np = VTONFS(vp); 1838 u_quad_t tsize; 1839 int biosize = vp->v_bufobj.bo_bsize; 1840 int error = 0; 1841 1842 mtx_lock(&np->n_mtx); 1843 tsize = np->n_size; 1844 np->n_size = nsize; 1845 mtx_unlock(&np->n_mtx); 1846 1847 if (nsize < tsize) { 1848 struct buf *bp; 1849 daddr_t lbn; 1850 int bufsize; 1851 1852 /* 1853 * vtruncbuf() doesn't get the buffer overlapping the 1854 * truncation point. We may have a B_DELWRI and/or B_CACHE 1855 * buffer that now needs to be truncated. 1856 */ 1857 error = vtruncbuf(vp, cred, nsize, biosize); 1858 lbn = nsize / biosize; 1859 bufsize = nsize - (lbn * biosize); 1860 bp = nfs_getcacheblk(vp, lbn, bufsize, td); 1861 if (!bp) 1862 return EINTR; 1863 if (bp->b_dirtyoff > bp->b_bcount) 1864 bp->b_dirtyoff = bp->b_bcount; 1865 if (bp->b_dirtyend > bp->b_bcount) 1866 bp->b_dirtyend = bp->b_bcount; 1867 bp->b_flags |= B_RELBUF; /* don't leave garbage around */ 1868 brelse(bp); 1869 } else { 1870 vnode_pager_setsize(vp, nsize); 1871 } 1872 return(error); 1873 } 1874 1875