1 /* $NetBSD: nfs_clbio.c,v 1.7 2021/03/29 02:13:37 simonb Exp $ */ 2 /*- 3 * Copyright (c) 1989, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * Rick Macklem at The University of Guelph. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95 34 */ 35 36 #include <sys/cdefs.h> 37 /* __FBSDID("FreeBSD: head/sys/fs/nfsclient/nfs_clbio.c 304026 2016-08-12 22:44:59Z rmacklem "); */ 38 __RCSID("$NetBSD: nfs_clbio.c,v 1.7 2021/03/29 02:13:37 simonb Exp $"); 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/buf.h> 43 #include <sys/kernel.h> 44 #include <sys/mount.h> 45 #include <sys/rwlock.h> 46 #include <sys/vmmeter.h> 47 #include <sys/vnode.h> 48 49 #include <fs/nfs/common/nfsport.h> 50 #include <fs/nfs/client/nfsmount.h> 51 #include <fs/nfs/client/nfs.h> 52 #include <fs/nfs/client/nfsnode.h> 53 #include <fs/nfs/client/nfs_kdtrace.h> 54 55 extern int newnfs_directio_allow_mmap; 56 extern struct nfsstatsv1 nfsstatsv1; 57 extern struct mtx ncl_iod_mutex; 58 extern int ncl_numasync; 59 extern enum nfsiod_state ncl_iodwant[NFS_MAXASYNCDAEMON]; 60 extern struct nfsmount *ncl_iodmount[NFS_MAXASYNCDAEMON]; 61 extern int newnfs_directio_enable; 62 extern int nfs_keep_dirty_on_error; 63 64 int ncl_pbuf_freecnt = -1; /* start out unlimited */ 65 66 static struct buf *nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, 67 struct thread *td); 68 static int nfs_directio_write(struct vnode *vp, struct uio *uiop, 69 struct ucred *cred, int ioflag); 70 71 /* 72 * Vnode op for VM getpages. 73 */ 74 int 75 ncl_getpages(struct vop_getpages_args *ap) 76 { 77 int i, error, nextoff, size, toff, count, npages; 78 struct uio uio; 79 struct iovec iov; 80 vaddr_t kva; 81 struct buf *bp; 82 struct vnode *vp; 83 struct thread *td; 84 struct ucred *cred; 85 struct nfsmount *nmp; 86 vm_object_t object; 87 vm_page_t *pages; 88 struct nfsnode *np; 89 90 vp = ap->a_vp; 91 np = VTONFS(vp); 92 td = curthread; /* XXX */ 93 cred = curthread->td_ucred; /* XXX */ 94 nmp = VFSTONFS(vp->v_mount); 95 pages = ap->a_m; 96 npages = ap->a_count; 97 98 if ((object = vp->v_object) == NULL) { 99 printf("ncl_getpages: called with non-merged cache vnode\n"); 100 return (VM_PAGER_ERROR); 101 } 102 103 if (newnfs_directio_enable && !newnfs_directio_allow_mmap) { 104 mtx_lock(&np->n_mtx); 105 if ((np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 106 mtx_unlock(&np->n_mtx); 107 printf("ncl_getpages: called on non-cacheable vnode\n"); 108 return (VM_PAGER_ERROR); 109 } else 110 mtx_unlock(&np->n_mtx); 111 } 112 113 mtx_lock(&nmp->nm_mtx); 114 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 115 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 116 mtx_unlock(&nmp->nm_mtx); 117 /* We'll never get here for v4, because we always have fsinfo */ 118 (void)ncl_fsinfo(nmp, vp, cred, td); 119 } else 120 mtx_unlock(&nmp->nm_mtx); 121 122 /* 123 * If the requested page is partially valid, just return it and 124 * allow the pager to zero-out the blanks. Partially valid pages 125 * can only occur at the file EOF. 126 * 127 * XXXGL: is that true for NFS, where short read can occur??? 128 */ 129 VM_OBJECT_WLOCK(object); 130 if (pages[npages - 1]->valid != 0 && --npages == 0) 131 goto out; 132 VM_OBJECT_WUNLOCK(object); 133 134 /* 135 * We use only the kva address for the buffer, but this is extremely 136 * convenient and fast. 137 */ 138 bp = getpbuf(&ncl_pbuf_freecnt); 139 140 kva = (vaddr_t) bp->b_data; 141 pmap_qenter(kva, pages, npages); 142 PCPU_INC(cnt.v_vnodein); 143 PCPU_ADD(cnt.v_vnodepgsin, npages); 144 145 count = npages << PAGE_SHIFT; 146 iov.iov_base = (caddr_t) kva; 147 iov.iov_len = count; 148 uio.uio_iov = &iov; 149 uio.uio_iovcnt = 1; 150 uio.uio_offset = IDX_TO_OFF(pages[0]->pindex); 151 uio.uio_resid = count; 152 uio.uio_segflg = UIO_SYSSPACE; 153 uio.uio_rw = UIO_READ; 154 uio.uio_td = td; 155 156 error = ncl_readrpc(vp, &uio, cred); 157 pmap_qremove(kva, npages); 158 159 relpbuf(bp, &ncl_pbuf_freecnt); 160 161 if (error && (uio.uio_resid == count)) { 162 printf("ncl_getpages: error %d\n", error); 163 return (VM_PAGER_ERROR); 164 } 165 166 /* 167 * Calculate the number of bytes read and validate only that number 168 * of bytes. Note that due to pending writes, size may be 0. This 169 * does not mean that the remaining data is invalid! 170 */ 171 172 size = count - uio.uio_resid; 173 VM_OBJECT_WLOCK(object); 174 for (i = 0, toff = 0; i < npages; i++, toff = nextoff) { 175 vm_page_t m; 176 nextoff = toff + PAGE_SIZE; 177 m = pages[i]; 178 179 if (nextoff <= size) { 180 /* 181 * Read operation filled an entire page 182 */ 183 m->valid = VM_PAGE_BITS_ALL; 184 KASSERT(m->dirty == 0, 185 ("nfs_getpages: page %p is dirty", m)); 186 } else if (size > toff) { 187 /* 188 * Read operation filled a partial page. 189 */ 190 m->valid = 0; 191 vm_page_set_valid_range(m, 0, size - toff); 192 KASSERT(m->dirty == 0, 193 ("nfs_getpages: page %p is dirty", m)); 194 } else { 195 /* 196 * Read operation was short. If no error 197 * occurred we may have hit a zero-fill 198 * section. We leave valid set to 0, and page 199 * is freed by vm_page_readahead_finish() if 200 * its index is not equal to requested, or 201 * page is zeroed and set valid by 202 * vm_pager_get_pages() for requested page. 203 */ 204 ; 205 } 206 } 207 out: 208 VM_OBJECT_WUNLOCK(object); 209 if (ap->a_rbehind) 210 *ap->a_rbehind = 0; 211 if (ap->a_rahead) 212 *ap->a_rahead = 0; 213 return (VM_PAGER_OK); 214 } 215 216 /* 217 * Vnode op for VM putpages. 218 */ 219 int 220 ncl_putpages(struct vop_putpages_args *ap) 221 { 222 struct uio uio; 223 struct iovec iov; 224 vaddr_t kva; 225 struct buf *bp; 226 int iomode, must_commit, i, error, npages, count; 227 off_t offset; 228 int *rtvals; 229 struct vnode *vp; 230 struct thread *td; 231 struct ucred *cred; 232 struct nfsmount *nmp; 233 struct nfsnode *np; 234 vm_page_t *pages; 235 236 vp = ap->a_vp; 237 np = VTONFS(vp); 238 td = curthread; /* XXX */ 239 /* Set the cred to n_writecred for the write rpcs. */ 240 if (np->n_writecred != NULL) 241 cred = crhold(np->n_writecred); 242 else 243 cred = crhold(curthread->td_ucred); /* XXX */ 244 nmp = VFSTONFS(vp->v_mount); 245 pages = ap->a_m; 246 count = ap->a_count; 247 rtvals = ap->a_rtvals; 248 npages = btoc(count); 249 offset = IDX_TO_OFF(pages[0]->pindex); 250 251 mtx_lock(&nmp->nm_mtx); 252 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 253 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 254 mtx_unlock(&nmp->nm_mtx); 255 (void)ncl_fsinfo(nmp, vp, cred, td); 256 } else 257 mtx_unlock(&nmp->nm_mtx); 258 259 mtx_lock(&np->n_mtx); 260 if (newnfs_directio_enable && !newnfs_directio_allow_mmap && 261 (np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 262 mtx_unlock(&np->n_mtx); 263 printf("ncl_putpages: called on noncache-able vnode\n"); 264 mtx_lock(&np->n_mtx); 265 } 266 267 for (i = 0; i < npages; i++) 268 rtvals[i] = VM_PAGER_ERROR; 269 270 /* 271 * When putting pages, do not extend file past EOF. 272 */ 273 if (offset + count > np->n_size) { 274 count = np->n_size - offset; 275 if (count < 0) 276 count = 0; 277 } 278 mtx_unlock(&np->n_mtx); 279 280 /* 281 * We use only the kva address for the buffer, but this is extremely 282 * convenient and fast. 283 */ 284 bp = getpbuf(&ncl_pbuf_freecnt); 285 286 kva = (vaddr_t) bp->b_data; 287 pmap_qenter(kva, pages, npages); 288 PCPU_INC(cnt.v_vnodeout); 289 PCPU_ADD(cnt.v_vnodepgsout, count); 290 291 iov.iov_base = (caddr_t) kva; 292 iov.iov_len = count; 293 uio.uio_iov = &iov; 294 uio.uio_iovcnt = 1; 295 uio.uio_offset = offset; 296 uio.uio_resid = count; 297 uio.uio_segflg = UIO_SYSSPACE; 298 uio.uio_rw = UIO_WRITE; 299 uio.uio_td = td; 300 301 if ((ap->a_sync & VM_PAGER_PUT_SYNC) == 0) 302 iomode = NFSWRITE_UNSTABLE; 303 else 304 iomode = NFSWRITE_FILESYNC; 305 306 error = ncl_writerpc(vp, &uio, cred, &iomode, &must_commit, 0); 307 crfree(cred); 308 309 pmap_qremove(kva, npages); 310 relpbuf(bp, &ncl_pbuf_freecnt); 311 312 if (error == 0 || !nfs_keep_dirty_on_error) { 313 vnode_pager_undirty_pages(pages, rtvals, count - uio.uio_resid); 314 if (must_commit) 315 ncl_clearcommit(vp->v_mount); 316 } 317 return rtvals[0]; 318 } 319 320 /* 321 * For nfs, cache consistency can only be maintained approximately. 322 * Although RFC1094 does not specify the criteria, the following is 323 * believed to be compatible with the reference port. 324 * For nfs: 325 * If the file's modify time on the server has changed since the 326 * last read rpc or you have written to the file, 327 * you may have lost data cache consistency with the 328 * server, so flush all of the file's data out of the cache. 329 * Then force a getattr rpc to ensure that you have up to date 330 * attributes. 331 * NB: This implies that cache data can be read when up to 332 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 333 * attributes this could be forced by setting n_attrstamp to 0 before 334 * the VOP_GETATTR() call. 335 */ 336 static inline int 337 nfs_bioread_check_cons(struct vnode *vp, struct thread *td, struct ucred *cred) 338 { 339 int error = 0; 340 struct vattr vattr; 341 struct nfsnode *np = VTONFS(vp); 342 int old_lock; 343 344 /* 345 * Grab the exclusive lock before checking whether the cache is 346 * consistent. 347 * XXX - We can make this cheaper later (by acquiring cheaper locks). 348 * But for now, this suffices. 349 */ 350 old_lock = ncl_upgrade_vnlock(vp); 351 if (vp->v_iflag & VI_DOOMED) { 352 ncl_downgrade_vnlock(vp, old_lock); 353 return (EBADF); 354 } 355 356 mtx_lock(&np->n_mtx); 357 if (np->n_flag & NMODIFIED) { 358 mtx_unlock(&np->n_mtx); 359 if (vp->v_type != VREG) { 360 if (vp->v_type != VDIR) 361 panic("nfs: bioread, not dir"); 362 ncl_invaldir(vp); 363 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 364 if (error) 365 goto out; 366 } 367 np->n_attrstamp = 0; 368 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 369 error = VOP_GETATTR(vp, &vattr, cred); 370 if (error) 371 goto out; 372 mtx_lock(&np->n_mtx); 373 np->n_mtime = vattr.va_mtime; 374 mtx_unlock(&np->n_mtx); 375 } else { 376 mtx_unlock(&np->n_mtx); 377 error = VOP_GETATTR(vp, &vattr, cred); 378 if (error) 379 return (error); 380 mtx_lock(&np->n_mtx); 381 if ((np->n_flag & NSIZECHANGED) 382 || (NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime))) { 383 mtx_unlock(&np->n_mtx); 384 if (vp->v_type == VDIR) 385 ncl_invaldir(vp); 386 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 387 if (error) 388 goto out; 389 mtx_lock(&np->n_mtx); 390 np->n_mtime = vattr.va_mtime; 391 np->n_flag &= ~NSIZECHANGED; 392 } 393 mtx_unlock(&np->n_mtx); 394 } 395 out: 396 ncl_downgrade_vnlock(vp, old_lock); 397 return error; 398 } 399 400 /* 401 * Vnode op for read using bio 402 */ 403 int 404 ncl_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred) 405 { 406 struct nfsnode *np = VTONFS(vp); 407 int biosize, i; 408 struct buf *bp, *rabp; 409 struct thread *td; 410 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 411 daddr_t lbn, rabn; 412 int bcount; 413 int seqcount; 414 int nra, error = 0, n = 0, on = 0; 415 off_t tmp_off; 416 417 KASSERT(uio->uio_rw == UIO_READ, ("ncl_read mode")); 418 if (uio->uio_resid == 0) 419 return (0); 420 if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */ 421 return (EINVAL); 422 td = uio->uio_td; 423 424 mtx_lock(&nmp->nm_mtx); 425 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 426 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 427 mtx_unlock(&nmp->nm_mtx); 428 (void)ncl_fsinfo(nmp, vp, cred, td); 429 mtx_lock(&nmp->nm_mtx); 430 } 431 if (nmp->nm_rsize == 0 || nmp->nm_readdirsize == 0) 432 (void) newnfs_iosize(nmp); 433 434 tmp_off = uio->uio_offset + uio->uio_resid; 435 if (vp->v_type != VDIR && 436 (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset)) { 437 mtx_unlock(&nmp->nm_mtx); 438 return (EFBIG); 439 } 440 mtx_unlock(&nmp->nm_mtx); 441 442 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && (vp->v_type == VREG)) 443 /* No caching/ no readaheads. Just read data into the user buffer */ 444 return ncl_readrpc(vp, uio, cred); 445 446 biosize = vp->v_bufobj.bo_bsize; 447 seqcount = (int)((off_t)(ioflag >> IO_SEQSHIFT) * biosize / BKVASIZE); 448 449 error = nfs_bioread_check_cons(vp, td, cred); 450 if (error) 451 return error; 452 453 do { 454 u_quad_t nsize; 455 456 mtx_lock(&np->n_mtx); 457 nsize = np->n_size; 458 mtx_unlock(&np->n_mtx); 459 460 switch (vp->v_type) { 461 case VREG: 462 NFSINCRGLOBAL(nfsstatsv1.biocache_reads); 463 lbn = uio->uio_offset / biosize; 464 on = uio->uio_offset - (lbn * biosize); 465 466 /* 467 * Start the read ahead(s), as required. 468 */ 469 if (nmp->nm_readahead > 0) { 470 for (nra = 0; nra < nmp->nm_readahead && nra < seqcount && 471 (off_t)(lbn + 1 + nra) * biosize < nsize; nra++) { 472 rabn = lbn + 1 + nra; 473 if (incore(&vp->v_bufobj, rabn) == NULL) { 474 rabp = nfs_getcacheblk(vp, rabn, biosize, td); 475 if (!rabp) { 476 error = newnfs_sigintr(nmp, td); 477 return (error ? error : EINTR); 478 } 479 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 480 rabp->b_flags |= B_ASYNC; 481 rabp->b_iocmd = BIO_READ; 482 vfs_busy_pages(rabp, 0); 483 if (ncl_asyncio(nmp, rabp, cred, td)) { 484 rabp->b_flags |= B_INVAL; 485 rabp->b_ioflags |= BIO_ERROR; 486 vfs_unbusy_pages(rabp); 487 brelse(rabp); 488 break; 489 } 490 } else { 491 brelse(rabp); 492 } 493 } 494 } 495 } 496 497 /* Note that bcount is *not* DEV_BSIZE aligned. */ 498 bcount = biosize; 499 if ((off_t)lbn * biosize >= nsize) { 500 bcount = 0; 501 } else if ((off_t)(lbn + 1) * biosize > nsize) { 502 bcount = nsize - (off_t)lbn * biosize; 503 } 504 bp = nfs_getcacheblk(vp, lbn, bcount, td); 505 506 if (!bp) { 507 error = newnfs_sigintr(nmp, td); 508 return (error ? error : EINTR); 509 } 510 511 /* 512 * If B_CACHE is not set, we must issue the read. If this 513 * fails, we return an error. 514 */ 515 516 if ((bp->b_flags & B_CACHE) == 0) { 517 bp->b_iocmd = BIO_READ; 518 vfs_busy_pages(bp, 0); 519 error = ncl_doio(vp, bp, cred, td, 0); 520 if (error) { 521 brelse(bp); 522 return (error); 523 } 524 } 525 526 /* 527 * on is the offset into the current bp. Figure out how many 528 * bytes we can copy out of the bp. Note that bcount is 529 * NOT DEV_BSIZE aligned. 530 * 531 * Then figure out how many bytes we can copy into the uio. 532 */ 533 534 n = 0; 535 if (on < bcount) 536 n = MIN((unsigned)(bcount - on), uio->uio_resid); 537 break; 538 case VLNK: 539 NFSINCRGLOBAL(nfsstatsv1.biocache_readlinks); 540 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, td); 541 if (!bp) { 542 error = newnfs_sigintr(nmp, td); 543 return (error ? error : EINTR); 544 } 545 if ((bp->b_flags & B_CACHE) == 0) { 546 bp->b_iocmd = BIO_READ; 547 vfs_busy_pages(bp, 0); 548 error = ncl_doio(vp, bp, cred, td, 0); 549 if (error) { 550 bp->b_ioflags |= BIO_ERROR; 551 brelse(bp); 552 return (error); 553 } 554 } 555 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 556 on = 0; 557 break; 558 case VDIR: 559 NFSINCRGLOBAL(nfsstatsv1.biocache_readdirs); 560 if (np->n_direofoffset 561 && uio->uio_offset >= np->n_direofoffset) { 562 return (0); 563 } 564 lbn = (uoff_t)uio->uio_offset / NFS_DIRBLKSIZ; 565 on = uio->uio_offset & (NFS_DIRBLKSIZ - 1); 566 bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, td); 567 if (!bp) { 568 error = newnfs_sigintr(nmp, td); 569 return (error ? error : EINTR); 570 } 571 if ((bp->b_flags & B_CACHE) == 0) { 572 bp->b_iocmd = BIO_READ; 573 vfs_busy_pages(bp, 0); 574 error = ncl_doio(vp, bp, cred, td, 0); 575 if (error) { 576 brelse(bp); 577 } 578 while (error == NFSERR_BAD_COOKIE) { 579 ncl_invaldir(vp); 580 error = ncl_vinvalbuf(vp, 0, td, 1); 581 /* 582 * Yuck! The directory has been modified on the 583 * server. The only way to get the block is by 584 * reading from the beginning to get all the 585 * offset cookies. 586 * 587 * Leave the last bp intact unless there is an error. 588 * Loop back up to the while if the error is another 589 * NFSERR_BAD_COOKIE (double yuch!). 590 */ 591 for (i = 0; i <= lbn && !error; i++) { 592 if (np->n_direofoffset 593 && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset) 594 return (0); 595 bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, td); 596 if (!bp) { 597 error = newnfs_sigintr(nmp, td); 598 return (error ? error : EINTR); 599 } 600 if ((bp->b_flags & B_CACHE) == 0) { 601 bp->b_iocmd = BIO_READ; 602 vfs_busy_pages(bp, 0); 603 error = ncl_doio(vp, bp, cred, td, 0); 604 /* 605 * no error + B_INVAL == directory EOF, 606 * use the block. 607 */ 608 if (error == 0 && (bp->b_flags & B_INVAL)) 609 break; 610 } 611 /* 612 * An error will throw away the block and the 613 * for loop will break out. If no error and this 614 * is not the block we want, we throw away the 615 * block and go for the next one via the for loop. 616 */ 617 if (error || i < lbn) 618 brelse(bp); 619 } 620 } 621 /* 622 * The above while is repeated if we hit another cookie 623 * error. If we hit an error and it wasn't a cookie error, 624 * we give up. 625 */ 626 if (error) 627 return (error); 628 } 629 630 /* 631 * If not eof and read aheads are enabled, start one. 632 * (You need the current block first, so that you have the 633 * directory offset cookie of the next block.) 634 */ 635 if (nmp->nm_readahead > 0 && 636 (bp->b_flags & B_INVAL) == 0 && 637 (np->n_direofoffset == 0 || 638 (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) && 639 incore(&vp->v_bufobj, lbn + 1) == NULL) { 640 rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td); 641 if (rabp) { 642 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 643 rabp->b_flags |= B_ASYNC; 644 rabp->b_iocmd = BIO_READ; 645 vfs_busy_pages(rabp, 0); 646 if (ncl_asyncio(nmp, rabp, cred, td)) { 647 rabp->b_flags |= B_INVAL; 648 rabp->b_ioflags |= BIO_ERROR; 649 vfs_unbusy_pages(rabp); 650 brelse(rabp); 651 } 652 } else { 653 brelse(rabp); 654 } 655 } 656 } 657 /* 658 * Unlike VREG files, whos buffer size ( bp->b_bcount ) is 659 * chopped for the EOF condition, we cannot tell how large 660 * NFS directories are going to be until we hit EOF. So 661 * an NFS directory buffer is *not* chopped to its EOF. Now, 662 * it just so happens that b_resid will effectively chop it 663 * to EOF. *BUT* this information is lost if the buffer goes 664 * away and is reconstituted into a B_CACHE state ( due to 665 * being VMIO ) later. So we keep track of the directory eof 666 * in np->n_direofoffset and chop it off as an extra step 667 * right here. 668 */ 669 n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on); 670 if (np->n_direofoffset && n > np->n_direofoffset - uio->uio_offset) 671 n = np->n_direofoffset - uio->uio_offset; 672 break; 673 default: 674 printf(" ncl_bioread: type %x unexpected\n", vp->v_type); 675 bp = NULL; 676 break; 677 } 678 679 if (n > 0) { 680 error = vn_io_fault_uiomove(bp->b_data + on, (int)n, uio); 681 } 682 if (vp->v_type == VLNK) 683 n = 0; 684 if (bp != NULL) 685 brelse(bp); 686 } while (error == 0 && uio->uio_resid > 0 && n > 0); 687 return (error); 688 } 689 690 /* 691 * The NFS write path cannot handle iovecs with len > 1. So we need to 692 * break up iovecs accordingly (restricting them to wsize). 693 * For the SYNC case, we can do this with 1 copy (user buffer -> mbuf). 694 * For the ASYNC case, 2 copies are needed. The first a copy from the 695 * user buffer to a staging buffer and then a second copy from the staging 696 * buffer to mbufs. This can be optimized by copying from the user buffer 697 * directly into mbufs and passing the chain down, but that requires a 698 * fair amount of re-working of the relevant codepaths (and can be done 699 * later). 700 */ 701 static int 702 nfs_directio_write(vp, uiop, cred, ioflag) 703 struct vnode *vp; 704 struct uio *uiop; 705 struct ucred *cred; 706 int ioflag; 707 { 708 int error; 709 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 710 struct thread *td = uiop->uio_td; 711 int size; 712 int wsize; 713 714 mtx_lock(&nmp->nm_mtx); 715 wsize = nmp->nm_wsize; 716 mtx_unlock(&nmp->nm_mtx); 717 if (ioflag & IO_SYNC) { 718 int iomode, must_commit; 719 struct uio uio; 720 struct iovec iov; 721 do_sync: 722 while (uiop->uio_resid > 0) { 723 size = MIN(uiop->uio_resid, wsize); 724 size = MIN(uiop->uio_iov->iov_len, size); 725 iov.iov_base = uiop->uio_iov->iov_base; 726 iov.iov_len = size; 727 uio.uio_iov = &iov; 728 uio.uio_iovcnt = 1; 729 uio.uio_offset = uiop->uio_offset; 730 uio.uio_resid = size; 731 uio.uio_segflg = UIO_USERSPACE; 732 uio.uio_rw = UIO_WRITE; 733 uio.uio_td = td; 734 iomode = NFSWRITE_FILESYNC; 735 error = ncl_writerpc(vp, &uio, cred, &iomode, 736 &must_commit, 0); 737 KASSERT((must_commit == 0), 738 ("ncl_directio_write: Did not commit write")); 739 if (error) 740 return (error); 741 uiop->uio_offset += size; 742 uiop->uio_resid -= size; 743 if (uiop->uio_iov->iov_len <= size) { 744 uiop->uio_iovcnt--; 745 uiop->uio_iov++; 746 } else { 747 uiop->uio_iov->iov_base = 748 (char *)uiop->uio_iov->iov_base + size; 749 uiop->uio_iov->iov_len -= size; 750 } 751 } 752 } else { 753 struct uio *t_uio; 754 struct iovec *t_iov; 755 struct buf *bp; 756 757 /* 758 * Break up the write into blocksize chunks and hand these 759 * over to nfsiod's for write back. 760 * Unfortunately, this incurs a copy of the data. Since 761 * the user could modify the buffer before the write is 762 * initiated. 763 * 764 * The obvious optimization here is that one of the 2 copies 765 * in the async write path can be eliminated by copying the 766 * data here directly into mbufs and passing the mbuf chain 767 * down. But that will require a fair amount of re-working 768 * of the code and can be done if there's enough interest 769 * in NFS directio access. 770 */ 771 while (uiop->uio_resid > 0) { 772 size = MIN(uiop->uio_resid, wsize); 773 size = MIN(uiop->uio_iov->iov_len, size); 774 bp = getpbuf(&ncl_pbuf_freecnt); 775 t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK); 776 t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK); 777 t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK); 778 t_iov->iov_len = size; 779 t_uio->uio_iov = t_iov; 780 t_uio->uio_iovcnt = 1; 781 t_uio->uio_offset = uiop->uio_offset; 782 t_uio->uio_resid = size; 783 t_uio->uio_segflg = UIO_SYSSPACE; 784 t_uio->uio_rw = UIO_WRITE; 785 t_uio->uio_td = td; 786 KASSERT(uiop->uio_segflg == UIO_USERSPACE || 787 uiop->uio_segflg == UIO_SYSSPACE, 788 ("nfs_directio_write: Bad uio_segflg")); 789 if (uiop->uio_segflg == UIO_USERSPACE) { 790 error = copyin(uiop->uio_iov->iov_base, 791 t_iov->iov_base, size); 792 if (error != 0) 793 goto err_free; 794 } else 795 /* 796 * UIO_SYSSPACE may never happen, but handle 797 * it just in case it does. 798 */ 799 bcopy(uiop->uio_iov->iov_base, t_iov->iov_base, 800 size); 801 bp->b_flags |= B_DIRECT; 802 bp->b_iocmd = BIO_WRITE; 803 if (cred != NOCRED) { 804 crhold(cred); 805 bp->b_wcred = cred; 806 } else 807 bp->b_wcred = NOCRED; 808 bp->b_caller1 = (void *)t_uio; 809 bp->b_vp = vp; 810 error = ncl_asyncio(nmp, bp, NOCRED, td); 811 err_free: 812 if (error) { 813 free(t_iov->iov_base, M_NFSDIRECTIO); 814 free(t_iov, M_NFSDIRECTIO); 815 free(t_uio, M_NFSDIRECTIO); 816 bp->b_vp = NULL; 817 relpbuf(bp, &ncl_pbuf_freecnt); 818 if (error == EINTR) 819 return (error); 820 goto do_sync; 821 } 822 uiop->uio_offset += size; 823 uiop->uio_resid -= size; 824 if (uiop->uio_iov->iov_len <= size) { 825 uiop->uio_iovcnt--; 826 uiop->uio_iov++; 827 } else { 828 uiop->uio_iov->iov_base = 829 (char *)uiop->uio_iov->iov_base + size; 830 uiop->uio_iov->iov_len -= size; 831 } 832 } 833 } 834 return (0); 835 } 836 837 /* 838 * Vnode op for write using bio 839 */ 840 int 841 ncl_write(struct vop_write_args *ap) 842 { 843 int biosize; 844 struct uio *uio = ap->a_uio; 845 struct thread *td = uio->uio_td; 846 struct vnode *vp = ap->a_vp; 847 struct nfsnode *np = VTONFS(vp); 848 struct ucred *cred = ap->a_cred; 849 int ioflag = ap->a_ioflag; 850 struct buf *bp; 851 struct vattr vattr; 852 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 853 daddr_t lbn; 854 int bcount, noncontig_write, obcount; 855 int bp_cached, n, on, error = 0, error1, wouldcommit; 856 size_t orig_resid, local_resid; 857 off_t orig_size, tmp_off; 858 859 KASSERT(uio->uio_rw == UIO_WRITE, ("ncl_write mode")); 860 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 861 ("ncl_write proc")); 862 if (vp->v_type != VREG) 863 return (EIO); 864 mtx_lock(&np->n_mtx); 865 if (np->n_flag & NWRITEERR) { 866 np->n_flag &= ~NWRITEERR; 867 mtx_unlock(&np->n_mtx); 868 return (np->n_error); 869 } else 870 mtx_unlock(&np->n_mtx); 871 mtx_lock(&nmp->nm_mtx); 872 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 873 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 874 mtx_unlock(&nmp->nm_mtx); 875 (void)ncl_fsinfo(nmp, vp, cred, td); 876 mtx_lock(&nmp->nm_mtx); 877 } 878 if (nmp->nm_wsize == 0) 879 (void) newnfs_iosize(nmp); 880 mtx_unlock(&nmp->nm_mtx); 881 882 /* 883 * Synchronously flush pending buffers if we are in synchronous 884 * mode or if we are appending. 885 */ 886 if (ioflag & (IO_APPEND | IO_SYNC)) { 887 mtx_lock(&np->n_mtx); 888 if (np->n_flag & NMODIFIED) { 889 mtx_unlock(&np->n_mtx); 890 #ifdef notyet /* Needs matching nonblock semantics elsewhere, too. */ 891 /* 892 * Require non-blocking, synchronous writes to 893 * dirty files to inform the program it needs 894 * to fsync(2) explicitly. 895 */ 896 if (ioflag & IO_NDELAY) 897 return (EAGAIN); 898 #endif 899 np->n_attrstamp = 0; 900 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 901 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 902 if (error) 903 return (error); 904 } else 905 mtx_unlock(&np->n_mtx); 906 } 907 908 orig_resid = uio->uio_resid; 909 mtx_lock(&np->n_mtx); 910 orig_size = np->n_size; 911 mtx_unlock(&np->n_mtx); 912 913 /* 914 * If IO_APPEND then load uio_offset. We restart here if we cannot 915 * get the append lock. 916 */ 917 if (ioflag & IO_APPEND) { 918 np->n_attrstamp = 0; 919 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 920 error = VOP_GETATTR(vp, &vattr, cred); 921 if (error) 922 return (error); 923 mtx_lock(&np->n_mtx); 924 uio->uio_offset = np->n_size; 925 mtx_unlock(&np->n_mtx); 926 } 927 928 if (uio->uio_offset < 0) 929 return (EINVAL); 930 tmp_off = uio->uio_offset + uio->uio_resid; 931 if (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset) 932 return (EFBIG); 933 if (uio->uio_resid == 0) 934 return (0); 935 936 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && vp->v_type == VREG) 937 return nfs_directio_write(vp, uio, cred, ioflag); 938 939 /* 940 * Maybe this should be above the vnode op call, but so long as 941 * file servers have no limits, i don't think it matters 942 */ 943 if (vn_rlimit_fsize(vp, uio, td)) 944 return (EFBIG); 945 946 biosize = vp->v_bufobj.bo_bsize; 947 /* 948 * Find all of this file's B_NEEDCOMMIT buffers. If our writes 949 * would exceed the local maximum per-file write commit size when 950 * combined with those, we must decide whether to flush, 951 * go synchronous, or return error. We don't bother checking 952 * IO_UNIT -- we just make all writes atomic anyway, as there's 953 * no point optimizing for something that really won't ever happen. 954 */ 955 wouldcommit = 0; 956 if (!(ioflag & IO_SYNC)) { 957 int nflag; 958 959 mtx_lock(&np->n_mtx); 960 nflag = np->n_flag; 961 mtx_unlock(&np->n_mtx); 962 if (nflag & NMODIFIED) { 963 BO_LOCK(&vp->v_bufobj); 964 if (vp->v_bufobj.bo_dirty.bv_cnt != 0) { 965 TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd, 966 b_bobufs) { 967 if (bp->b_flags & B_NEEDCOMMIT) 968 wouldcommit += bp->b_bcount; 969 } 970 } 971 BO_UNLOCK(&vp->v_bufobj); 972 } 973 } 974 975 do { 976 if (!(ioflag & IO_SYNC)) { 977 wouldcommit += biosize; 978 if (wouldcommit > nmp->nm_wcommitsize) { 979 np->n_attrstamp = 0; 980 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 981 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 982 if (error) 983 return (error); 984 wouldcommit = biosize; 985 } 986 } 987 988 NFSINCRGLOBAL(nfsstatsv1.biocache_writes); 989 lbn = uio->uio_offset / biosize; 990 on = uio->uio_offset - (lbn * biosize); 991 n = MIN((unsigned)(biosize - on), uio->uio_resid); 992 again: 993 /* 994 * Handle direct append and file extension cases, calculate 995 * unaligned buffer size. 996 */ 997 mtx_lock(&np->n_mtx); 998 if ((np->n_flag & NHASBEENLOCKED) == 0 && 999 (nmp->nm_flag & NFSMNT_NONCONTIGWR) != 0) 1000 noncontig_write = 1; 1001 else 1002 noncontig_write = 0; 1003 if ((uio->uio_offset == np->n_size || 1004 (noncontig_write != 0 && 1005 lbn == (np->n_size / biosize) && 1006 uio->uio_offset + n > np->n_size)) && n) { 1007 mtx_unlock(&np->n_mtx); 1008 /* 1009 * Get the buffer (in its pre-append state to maintain 1010 * B_CACHE if it was previously set). Resize the 1011 * nfsnode after we have locked the buffer to prevent 1012 * readers from reading garbage. 1013 */ 1014 obcount = np->n_size - (lbn * biosize); 1015 bp = nfs_getcacheblk(vp, lbn, obcount, td); 1016 1017 if (bp != NULL) { 1018 long save; 1019 1020 mtx_lock(&np->n_mtx); 1021 np->n_size = uio->uio_offset + n; 1022 np->n_flag |= NMODIFIED; 1023 vnode_pager_setsize(vp, np->n_size); 1024 mtx_unlock(&np->n_mtx); 1025 1026 save = bp->b_flags & B_CACHE; 1027 bcount = on + n; 1028 allocbuf(bp, bcount); 1029 bp->b_flags |= save; 1030 if (noncontig_write != 0 && on > obcount) 1031 vfs_bio_bzero_buf(bp, obcount, on - 1032 obcount); 1033 } 1034 } else { 1035 /* 1036 * Obtain the locked cache block first, and then 1037 * adjust the file's size as appropriate. 1038 */ 1039 bcount = on + n; 1040 if ((off_t)lbn * biosize + bcount < np->n_size) { 1041 if ((off_t)(lbn + 1) * biosize < np->n_size) 1042 bcount = biosize; 1043 else 1044 bcount = np->n_size - (off_t)lbn * biosize; 1045 } 1046 mtx_unlock(&np->n_mtx); 1047 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1048 mtx_lock(&np->n_mtx); 1049 if (uio->uio_offset + n > np->n_size) { 1050 np->n_size = uio->uio_offset + n; 1051 np->n_flag |= NMODIFIED; 1052 vnode_pager_setsize(vp, np->n_size); 1053 } 1054 mtx_unlock(&np->n_mtx); 1055 } 1056 1057 if (!bp) { 1058 error = newnfs_sigintr(nmp, td); 1059 if (!error) 1060 error = EINTR; 1061 break; 1062 } 1063 1064 /* 1065 * Issue a READ if B_CACHE is not set. In special-append 1066 * mode, B_CACHE is based on the buffer prior to the write 1067 * op and is typically set, avoiding the read. If a read 1068 * is required in special append mode, the server will 1069 * probably send us a short-read since we extended the file 1070 * on our end, resulting in b_resid == 0 and, thusly, 1071 * B_CACHE getting set. 1072 * 1073 * We can also avoid issuing the read if the write covers 1074 * the entire buffer. We have to make sure the buffer state 1075 * is reasonable in this case since we will not be initiating 1076 * I/O. See the comments in kern/vfs_bio.c's getblk() for 1077 * more information. 1078 * 1079 * B_CACHE may also be set due to the buffer being cached 1080 * normally. 1081 */ 1082 1083 bp_cached = 1; 1084 if (on == 0 && n == bcount) { 1085 if ((bp->b_flags & B_CACHE) == 0) 1086 bp_cached = 0; 1087 bp->b_flags |= B_CACHE; 1088 bp->b_flags &= ~B_INVAL; 1089 bp->b_ioflags &= ~BIO_ERROR; 1090 } 1091 1092 if ((bp->b_flags & B_CACHE) == 0) { 1093 bp->b_iocmd = BIO_READ; 1094 vfs_busy_pages(bp, 0); 1095 error = ncl_doio(vp, bp, cred, td, 0); 1096 if (error) { 1097 brelse(bp); 1098 break; 1099 } 1100 } 1101 if (bp->b_wcred == NOCRED) 1102 bp->b_wcred = crhold(cred); 1103 mtx_lock(&np->n_mtx); 1104 np->n_flag |= NMODIFIED; 1105 mtx_unlock(&np->n_mtx); 1106 1107 /* 1108 * If dirtyend exceeds file size, chop it down. This should 1109 * not normally occur but there is an append race where it 1110 * might occur XXX, so we log it. 1111 * 1112 * If the chopping creates a reverse-indexed or degenerate 1113 * situation with dirtyoff/end, we 0 both of them. 1114 */ 1115 1116 if (bp->b_dirtyend > bcount) { 1117 printf("NFS append race @%lx:%d\n", 1118 (long)bp->b_blkno * DEV_BSIZE, 1119 bp->b_dirtyend - bcount); 1120 bp->b_dirtyend = bcount; 1121 } 1122 1123 if (bp->b_dirtyoff >= bp->b_dirtyend) 1124 bp->b_dirtyoff = bp->b_dirtyend = 0; 1125 1126 /* 1127 * If the new write will leave a contiguous dirty 1128 * area, just update the b_dirtyoff and b_dirtyend, 1129 * otherwise force a write rpc of the old dirty area. 1130 * 1131 * If there has been a file lock applied to this file 1132 * or vfs.nfs.old_noncontig_writing is set, do the following: 1133 * While it is possible to merge discontiguous writes due to 1134 * our having a B_CACHE buffer ( and thus valid read data 1135 * for the hole), we don't because it could lead to 1136 * significant cache coherency problems with multiple clients, 1137 * especially if locking is implemented later on. 1138 * 1139 * If vfs.nfs.old_noncontig_writing is not set and there has 1140 * not been file locking done on this file: 1141 * Relax coherency a bit for the sake of performance and 1142 * expand the current dirty region to contain the new 1143 * write even if it means we mark some non-dirty data as 1144 * dirty. 1145 */ 1146 1147 if (noncontig_write == 0 && bp->b_dirtyend > 0 && 1148 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 1149 if (bwrite(bp) == EINTR) { 1150 error = EINTR; 1151 break; 1152 } 1153 goto again; 1154 } 1155 1156 local_resid = uio->uio_resid; 1157 error = vn_io_fault_uiomove((char *)bp->b_data + on, n, uio); 1158 1159 if (error != 0 && !bp_cached) { 1160 /* 1161 * This block has no other content than what 1162 * possibly was written by the faulty uiomove. 1163 * Release it, forgetting the data pages, to 1164 * prevent the leak of uninitialized data to 1165 * usermode. 1166 */ 1167 bp->b_ioflags |= BIO_ERROR; 1168 brelse(bp); 1169 uio->uio_offset -= local_resid - uio->uio_resid; 1170 uio->uio_resid = local_resid; 1171 break; 1172 } 1173 1174 /* 1175 * Since this block is being modified, it must be written 1176 * again and not just committed. Since write clustering does 1177 * not work for the stage 1 data write, only the stage 2 1178 * commit rpc, we have to clear B_CLUSTEROK as well. 1179 */ 1180 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1181 1182 /* 1183 * Get the partial update on the progress made from 1184 * uiomove, if an error occurred. 1185 */ 1186 if (error != 0) 1187 n = local_resid - uio->uio_resid; 1188 1189 /* 1190 * Only update dirtyoff/dirtyend if not a degenerate 1191 * condition. 1192 */ 1193 if (n > 0) { 1194 if (bp->b_dirtyend > 0) { 1195 bp->b_dirtyoff = uimin(on, bp->b_dirtyoff); 1196 bp->b_dirtyend = uimax((on + n), bp->b_dirtyend); 1197 } else { 1198 bp->b_dirtyoff = on; 1199 bp->b_dirtyend = on + n; 1200 } 1201 vfs_bio_set_valid(bp, on, n); 1202 } 1203 1204 /* 1205 * If IO_SYNC do bwrite(). 1206 * 1207 * IO_INVAL appears to be unused. The idea appears to be 1208 * to turn off caching in this case. Very odd. XXX 1209 */ 1210 if ((ioflag & IO_SYNC)) { 1211 if (ioflag & IO_INVAL) 1212 bp->b_flags |= B_NOCACHE; 1213 error1 = bwrite(bp); 1214 if (error1 != 0) { 1215 if (error == 0) 1216 error = error1; 1217 break; 1218 } 1219 } else if ((n + on) == biosize) { 1220 bp->b_flags |= B_ASYNC; 1221 (void) ncl_writebp(bp, 0, NULL); 1222 } else { 1223 bdwrite(bp); 1224 } 1225 1226 if (error != 0) 1227 break; 1228 } while (uio->uio_resid > 0 && n > 0); 1229 1230 if (error != 0) { 1231 if (ioflag & IO_UNIT) { 1232 VATTR_NULL(&vattr); 1233 vattr.va_size = orig_size; 1234 /* IO_SYNC is handled implicitly */ 1235 (void)VOP_SETATTR(vp, &vattr, cred); 1236 uio->uio_offset -= orig_resid - uio->uio_resid; 1237 uio->uio_resid = orig_resid; 1238 } 1239 } 1240 1241 return (error); 1242 } 1243 1244 /* 1245 * Get an nfs cache block. 1246 * 1247 * Allocate a new one if the block isn't currently in the cache 1248 * and return the block marked busy. If the calling process is 1249 * interrupted by a signal for an interruptible mount point, return 1250 * NULL. 1251 * 1252 * The caller must carefully deal with the possible B_INVAL state of 1253 * the buffer. ncl_doio() clears B_INVAL (and ncl_asyncio() clears it 1254 * indirectly), so synchronous reads can be issued without worrying about 1255 * the B_INVAL state. We have to be a little more careful when dealing 1256 * with writes (see comments in nfs_write()) when extending a file past 1257 * its EOF. 1258 */ 1259 static struct buf * 1260 nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td) 1261 { 1262 struct buf *bp; 1263 struct mount *mp; 1264 struct nfsmount *nmp; 1265 1266 mp = vp->v_mount; 1267 nmp = VFSTONFS(mp); 1268 1269 if (nmp->nm_flag & NFSMNT_INT) { 1270 sigset_t oldset; 1271 1272 newnfs_set_sigmask(td, &oldset); 1273 bp = getblk(vp, bn, size, PCATCH, 0, 0); 1274 newnfs_restore_sigmask(td, &oldset); 1275 while (bp == NULL) { 1276 if (newnfs_sigintr(nmp, td)) 1277 return (NULL); 1278 bp = getblk(vp, bn, size, 0, 2 * hz, 0); 1279 } 1280 } else { 1281 bp = getblk(vp, bn, size, 0, 0, 0); 1282 } 1283 1284 if (vp->v_type == VREG) 1285 bp->b_blkno = bn * (vp->v_bufobj.bo_bsize / DEV_BSIZE); 1286 return (bp); 1287 } 1288 1289 /* 1290 * Flush and invalidate all dirty buffers. If another process is already 1291 * doing the flush, just wait for completion. 1292 */ 1293 int 1294 ncl_vinvalbuf(struct vnode *vp, int flags, struct thread *td, int intrflg) 1295 { 1296 struct nfsnode *np = VTONFS(vp); 1297 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1298 int error = 0, slpflag, slptimeo; 1299 int old_lock = 0; 1300 1301 ASSERT_VOP_LOCKED(vp, "ncl_vinvalbuf"); 1302 1303 if ((nmp->nm_flag & NFSMNT_INT) == 0) 1304 intrflg = 0; 1305 if ((nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF)) 1306 intrflg = 1; 1307 if (intrflg) { 1308 slpflag = PCATCH; 1309 slptimeo = 2 * hz; 1310 } else { 1311 slpflag = 0; 1312 slptimeo = 0; 1313 } 1314 1315 old_lock = ncl_upgrade_vnlock(vp); 1316 if (vp->v_iflag & VI_DOOMED) { 1317 /* 1318 * Since vgonel() uses the generic vinvalbuf() to flush 1319 * dirty buffers and it does not call this function, it 1320 * is safe to just return OK when VI_DOOMED is set. 1321 */ 1322 ncl_downgrade_vnlock(vp, old_lock); 1323 return (0); 1324 } 1325 1326 /* 1327 * Now, flush as required. 1328 */ 1329 if ((flags & V_SAVE) && (vp->v_bufobj.bo_object != NULL)) { 1330 VM_OBJECT_WLOCK(vp->v_bufobj.bo_object); 1331 vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC); 1332 VM_OBJECT_WUNLOCK(vp->v_bufobj.bo_object); 1333 /* 1334 * If the page clean was interrupted, fail the invalidation. 1335 * Not doing so, we run the risk of losing dirty pages in the 1336 * vinvalbuf() call below. 1337 */ 1338 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1339 goto out; 1340 } 1341 1342 error = vinvalbuf(vp, flags, slpflag, 0); 1343 while (error) { 1344 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1345 goto out; 1346 error = vinvalbuf(vp, flags, 0, slptimeo); 1347 } 1348 if (NFSHASPNFS(nmp)) { 1349 nfscl_layoutcommit(vp, td); 1350 /* 1351 * Invalidate the attribute cache, since writes to a DS 1352 * won't update the size attribute. 1353 */ 1354 mtx_lock(&np->n_mtx); 1355 np->n_attrstamp = 0; 1356 } else 1357 mtx_lock(&np->n_mtx); 1358 if (np->n_directio_asyncwr == 0) 1359 np->n_flag &= ~NMODIFIED; 1360 mtx_unlock(&np->n_mtx); 1361 out: 1362 ncl_downgrade_vnlock(vp, old_lock); 1363 return error; 1364 } 1365 1366 /* 1367 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 1368 * This is mainly to avoid queueing async I/O requests when the nfsiods 1369 * are all hung on a dead server. 1370 * 1371 * Note: ncl_asyncio() does not clear (BIO_ERROR|B_INVAL) but when the bp 1372 * is eventually dequeued by the async daemon, ncl_doio() *will*. 1373 */ 1374 int 1375 ncl_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td) 1376 { 1377 int iod; 1378 int gotiod; 1379 int slpflag = 0; 1380 int slptimeo = 0; 1381 int error, error2; 1382 1383 /* 1384 * Commits are usually short and sweet so lets save some cpu and 1385 * leave the async daemons for more important rpc's (such as reads 1386 * and writes). 1387 * 1388 * Readdirplus RPCs do vget()s to acquire the vnodes for entries 1389 * in the directory in order to update attributes. This can deadlock 1390 * with another thread that is waiting for async I/O to be done by 1391 * an nfsiod thread while holding a lock on one of these vnodes. 1392 * To avoid this deadlock, don't allow the async nfsiod threads to 1393 * perform Readdirplus RPCs. 1394 */ 1395 mtx_lock(&ncl_iod_mutex); 1396 if ((bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) && 1397 (nmp->nm_bufqiods > ncl_numasync / 2)) || 1398 (bp->b_vp->v_type == VDIR && (nmp->nm_flag & NFSMNT_RDIRPLUS))) { 1399 mtx_unlock(&ncl_iod_mutex); 1400 return(EIO); 1401 } 1402 again: 1403 if (nmp->nm_flag & NFSMNT_INT) 1404 slpflag = PCATCH; 1405 gotiod = FALSE; 1406 1407 /* 1408 * Find a free iod to process this request. 1409 */ 1410 for (iod = 0; iod < ncl_numasync; iod++) 1411 if (ncl_iodwant[iod] == NFSIOD_AVAILABLE) { 1412 gotiod = TRUE; 1413 break; 1414 } 1415 1416 /* 1417 * Try to create one if none are free. 1418 */ 1419 if (!gotiod) 1420 ncl_nfsiodnew(); 1421 else { 1422 /* 1423 * Found one, so wake it up and tell it which 1424 * mount to process. 1425 */ 1426 NFS_DPF(ASYNCIO, ("ncl_asyncio: waking iod %d for mount %p\n", 1427 iod, nmp)); 1428 ncl_iodwant[iod] = NFSIOD_NOT_AVAILABLE; 1429 ncl_iodmount[iod] = nmp; 1430 nmp->nm_bufqiods++; 1431 wakeup(&ncl_iodwant[iod]); 1432 } 1433 1434 /* 1435 * If none are free, we may already have an iod working on this mount 1436 * point. If so, it will process our request. 1437 */ 1438 if (!gotiod) { 1439 if (nmp->nm_bufqiods > 0) { 1440 NFS_DPF(ASYNCIO, 1441 ("ncl_asyncio: %d iods are already processing mount %p\n", 1442 nmp->nm_bufqiods, nmp)); 1443 gotiod = TRUE; 1444 } 1445 } 1446 1447 /* 1448 * If we have an iod which can process the request, then queue 1449 * the buffer. 1450 */ 1451 if (gotiod) { 1452 /* 1453 * Ensure that the queue never grows too large. We still want 1454 * to asynchronize so we block rather than return EIO. 1455 */ 1456 while (nmp->nm_bufqlen >= 2*ncl_numasync) { 1457 NFS_DPF(ASYNCIO, 1458 ("ncl_asyncio: waiting for mount %p queue to drain\n", nmp)); 1459 nmp->nm_bufqwant = TRUE; 1460 error = newnfs_msleep(td, &nmp->nm_bufq, 1461 &ncl_iod_mutex, slpflag | PRIBIO, "nfsaio", 1462 slptimeo); 1463 if (error) { 1464 error2 = newnfs_sigintr(nmp, td); 1465 if (error2) { 1466 mtx_unlock(&ncl_iod_mutex); 1467 return (error2); 1468 } 1469 if (slpflag == PCATCH) { 1470 slpflag = 0; 1471 slptimeo = 2 * hz; 1472 } 1473 } 1474 /* 1475 * We might have lost our iod while sleeping, 1476 * so check and loop if necessary. 1477 */ 1478 goto again; 1479 } 1480 1481 /* We might have lost our nfsiod */ 1482 if (nmp->nm_bufqiods == 0) { 1483 NFS_DPF(ASYNCIO, 1484 ("ncl_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); 1485 goto again; 1486 } 1487 1488 if (bp->b_iocmd == BIO_READ) { 1489 if (bp->b_rcred == NOCRED && cred != NOCRED) 1490 bp->b_rcred = crhold(cred); 1491 } else { 1492 if (bp->b_wcred == NOCRED && cred != NOCRED) 1493 bp->b_wcred = crhold(cred); 1494 } 1495 1496 if (bp->b_flags & B_REMFREE) 1497 bremfreef(bp); 1498 BUF_KERNPROC(bp); 1499 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 1500 nmp->nm_bufqlen++; 1501 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1502 mtx_lock(&(VTONFS(bp->b_vp))->n_mtx); 1503 VTONFS(bp->b_vp)->n_flag |= NMODIFIED; 1504 VTONFS(bp->b_vp)->n_directio_asyncwr++; 1505 mtx_unlock(&(VTONFS(bp->b_vp))->n_mtx); 1506 } 1507 mtx_unlock(&ncl_iod_mutex); 1508 return (0); 1509 } 1510 1511 mtx_unlock(&ncl_iod_mutex); 1512 1513 /* 1514 * All the iods are busy on other mounts, so return EIO to 1515 * force the caller to process the i/o synchronously. 1516 */ 1517 NFS_DPF(ASYNCIO, ("ncl_asyncio: no iods available, i/o is synchronous\n")); 1518 return (EIO); 1519 } 1520 1521 void 1522 ncl_doio_directwrite(struct buf *bp) 1523 { 1524 int iomode, must_commit; 1525 struct uio *uiop = (struct uio *)bp->b_caller1; 1526 char *iov_base = uiop->uio_iov->iov_base; 1527 1528 iomode = NFSWRITE_FILESYNC; 1529 uiop->uio_td = NULL; /* NULL since we're in nfsiod */ 1530 ncl_writerpc(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit, 0); 1531 KASSERT((must_commit == 0), ("ncl_doio_directwrite: Did not commit write")); 1532 free(iov_base, M_NFSDIRECTIO); 1533 free(uiop->uio_iov, M_NFSDIRECTIO); 1534 free(uiop, M_NFSDIRECTIO); 1535 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1536 struct nfsnode *np = VTONFS(bp->b_vp); 1537 mtx_lock(&np->n_mtx); 1538 if (NFSHASPNFS(VFSTONFS(vnode_mount(bp->b_vp)))) { 1539 /* 1540 * Invalidate the attribute cache, since writes to a DS 1541 * won't update the size attribute. 1542 */ 1543 np->n_attrstamp = 0; 1544 } 1545 np->n_directio_asyncwr--; 1546 if (np->n_directio_asyncwr == 0) { 1547 np->n_flag &= ~NMODIFIED; 1548 if ((np->n_flag & NFSYNCWAIT)) { 1549 np->n_flag &= ~NFSYNCWAIT; 1550 wakeup((caddr_t)&np->n_directio_asyncwr); 1551 } 1552 } 1553 mtx_unlock(&np->n_mtx); 1554 } 1555 bp->b_vp = NULL; 1556 relpbuf(bp, &ncl_pbuf_freecnt); 1557 } 1558 1559 /* 1560 * Do an I/O operation to/from a cache block. This may be called 1561 * synchronously or from an nfsiod. 1562 */ 1563 int 1564 ncl_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td, 1565 int called_from_strategy) 1566 { 1567 struct uio *uiop; 1568 struct nfsnode *np; 1569 struct nfsmount *nmp; 1570 int error = 0, iomode, must_commit = 0; 1571 struct uio uio; 1572 struct iovec io; 1573 struct proc *p = td ? td->td_proc : NULL; 1574 uint8_t iocmd; 1575 1576 np = VTONFS(vp); 1577 nmp = VFSTONFS(vp->v_mount); 1578 uiop = &uio; 1579 uiop->uio_iov = &io; 1580 uiop->uio_iovcnt = 1; 1581 uiop->uio_segflg = UIO_SYSSPACE; 1582 uiop->uio_td = td; 1583 1584 /* 1585 * clear BIO_ERROR and B_INVAL state prior to initiating the I/O. We 1586 * do this here so we do not have to do it in all the code that 1587 * calls us. 1588 */ 1589 bp->b_flags &= ~B_INVAL; 1590 bp->b_ioflags &= ~BIO_ERROR; 1591 1592 KASSERT(!(bp->b_flags & B_DONE), ("ncl_doio: bp %p already marked done", bp)); 1593 iocmd = bp->b_iocmd; 1594 if (iocmd == BIO_READ) { 1595 io.iov_len = uiop->uio_resid = bp->b_bcount; 1596 io.iov_base = bp->b_data; 1597 uiop->uio_rw = UIO_READ; 1598 1599 switch (vp->v_type) { 1600 case VREG: 1601 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1602 NFSINCRGLOBAL(nfsstatsv1.read_bios); 1603 error = ncl_readrpc(vp, uiop, cr); 1604 1605 if (!error) { 1606 if (uiop->uio_resid) { 1607 /* 1608 * If we had a short read with no error, we must have 1609 * hit a file hole. We should zero-fill the remainder. 1610 * This can also occur if the server hits the file EOF. 1611 * 1612 * Holes used to be able to occur due to pending 1613 * writes, but that is not possible any longer. 1614 */ 1615 int nread = bp->b_bcount - uiop->uio_resid; 1616 ssize_t left = uiop->uio_resid; 1617 1618 if (left > 0) 1619 bzero((char *)bp->b_data + nread, left); 1620 uiop->uio_resid = 0; 1621 } 1622 } 1623 /* ASSERT_VOP_LOCKED(vp, "ncl_doio"); */ 1624 if (p && (vp->v_vflag & VV_TEXT)) { 1625 mtx_lock(&np->n_mtx); 1626 if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.na_mtime)) { 1627 mtx_unlock(&np->n_mtx); 1628 PROC_LOCK(p); 1629 killproc(p, "text file modification"); 1630 PROC_UNLOCK(p); 1631 } else 1632 mtx_unlock(&np->n_mtx); 1633 } 1634 break; 1635 case VLNK: 1636 uiop->uio_offset = (off_t)0; 1637 NFSINCRGLOBAL(nfsstatsv1.readlink_bios); 1638 error = ncl_readlinkrpc(vp, uiop, cr); 1639 break; 1640 case VDIR: 1641 NFSINCRGLOBAL(nfsstatsv1.readdir_bios); 1642 uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ; 1643 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) != 0) { 1644 error = ncl_readdirplusrpc(vp, uiop, cr, td); 1645 if (error == NFSERR_NOTSUPP) 1646 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 1647 } 1648 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 1649 error = ncl_readdirrpc(vp, uiop, cr, td); 1650 /* 1651 * end-of-directory sets B_INVAL but does not generate an 1652 * error. 1653 */ 1654 if (error == 0 && uiop->uio_resid == bp->b_bcount) 1655 bp->b_flags |= B_INVAL; 1656 break; 1657 default: 1658 printf("ncl_doio: type %x unexpected\n", vp->v_type); 1659 break; 1660 } 1661 if (error) { 1662 bp->b_ioflags |= BIO_ERROR; 1663 bp->b_error = error; 1664 } 1665 } else { 1666 /* 1667 * If we only need to commit, try to commit 1668 */ 1669 if (bp->b_flags & B_NEEDCOMMIT) { 1670 int retv; 1671 off_t off; 1672 1673 off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff; 1674 retv = ncl_commit(vp, off, bp->b_dirtyend-bp->b_dirtyoff, 1675 bp->b_wcred, td); 1676 if (retv == 0) { 1677 bp->b_dirtyoff = bp->b_dirtyend = 0; 1678 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1679 bp->b_resid = 0; 1680 bufdone(bp); 1681 return (0); 1682 } 1683 if (retv == NFSERR_STALEWRITEVERF) { 1684 ncl_clearcommit(vp->v_mount); 1685 } 1686 } 1687 1688 /* 1689 * Setup for actual write 1690 */ 1691 mtx_lock(&np->n_mtx); 1692 if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size) 1693 bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE; 1694 mtx_unlock(&np->n_mtx); 1695 1696 if (bp->b_dirtyend > bp->b_dirtyoff) { 1697 io.iov_len = uiop->uio_resid = bp->b_dirtyend 1698 - bp->b_dirtyoff; 1699 uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE 1700 + bp->b_dirtyoff; 1701 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 1702 uiop->uio_rw = UIO_WRITE; 1703 NFSINCRGLOBAL(nfsstatsv1.write_bios); 1704 1705 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC) 1706 iomode = NFSWRITE_UNSTABLE; 1707 else 1708 iomode = NFSWRITE_FILESYNC; 1709 1710 error = ncl_writerpc(vp, uiop, cr, &iomode, &must_commit, 1711 called_from_strategy); 1712 1713 /* 1714 * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try 1715 * to cluster the buffers needing commit. This will allow 1716 * the system to submit a single commit rpc for the whole 1717 * cluster. We can do this even if the buffer is not 100% 1718 * dirty (relative to the NFS blocksize), so we optimize the 1719 * append-to-file-case. 1720 * 1721 * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be 1722 * cleared because write clustering only works for commit 1723 * rpc's, not for the data portion of the write). 1724 */ 1725 1726 if (!error && iomode == NFSWRITE_UNSTABLE) { 1727 bp->b_flags |= B_NEEDCOMMIT; 1728 if (bp->b_dirtyoff == 0 1729 && bp->b_dirtyend == bp->b_bcount) 1730 bp->b_flags |= B_CLUSTEROK; 1731 } else { 1732 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1733 } 1734 1735 /* 1736 * For an interrupted write, the buffer is still valid 1737 * and the write hasn't been pushed to the server yet, 1738 * so we can't set BIO_ERROR and report the interruption 1739 * by setting B_EINTR. For the B_ASYNC case, B_EINTR 1740 * is not relevant, so the rpc attempt is essentially 1741 * a noop. For the case of a V3 write rpc not being 1742 * committed to stable storage, the block is still 1743 * dirty and requires either a commit rpc or another 1744 * write rpc with iomode == NFSV3WRITE_FILESYNC before 1745 * the block is reused. This is indicated by setting 1746 * the B_DELWRI and B_NEEDCOMMIT flags. 1747 * 1748 * EIO is returned by ncl_writerpc() to indicate a recoverable 1749 * write error and is handled as above, except that 1750 * B_EINTR isn't set. One cause of this is a stale stateid 1751 * error for the RPC that indicates recovery is required, 1752 * when called with called_from_strategy != 0. 1753 * 1754 * If the buffer is marked B_PAGING, it does not reside on 1755 * the vp's paging queues so we cannot call bdirty(). The 1756 * bp in this case is not an NFS cache block so we should 1757 * be safe. XXX 1758 * 1759 * The logic below breaks up errors into recoverable and 1760 * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE 1761 * and keep the buffer around for potential write retries. 1762 * For the latter (eg ESTALE), we toss the buffer away (B_INVAL) 1763 * and save the error in the nfsnode. This is less than ideal 1764 * but necessary. Keeping such buffers around could potentially 1765 * cause buffer exhaustion eventually (they can never be written 1766 * out, so will get constantly be re-dirtied). It also causes 1767 * all sorts of vfs panics. For non-recoverable write errors, 1768 * also invalidate the attrcache, so we'll be forced to go over 1769 * the wire for this object, returning an error to user on next 1770 * call (most of the time). 1771 */ 1772 if (error == EINTR || error == EIO || error == ETIMEDOUT 1773 || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 1774 int s; 1775 1776 s = splbio(); 1777 bp->b_flags &= ~(B_INVAL|B_NOCACHE); 1778 if ((bp->b_flags & B_PAGING) == 0) { 1779 bdirty(bp); 1780 bp->b_flags &= ~B_DONE; 1781 } 1782 if ((error == EINTR || error == ETIMEDOUT) && 1783 (bp->b_flags & B_ASYNC) == 0) 1784 bp->b_flags |= B_EINTR; 1785 splx(s); 1786 } else { 1787 if (error) { 1788 bp->b_ioflags |= BIO_ERROR; 1789 bp->b_flags |= B_INVAL; 1790 bp->b_error = np->n_error = error; 1791 mtx_lock(&np->n_mtx); 1792 np->n_flag |= NWRITEERR; 1793 np->n_attrstamp = 0; 1794 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 1795 mtx_unlock(&np->n_mtx); 1796 } 1797 bp->b_dirtyoff = bp->b_dirtyend = 0; 1798 } 1799 } else { 1800 bp->b_resid = 0; 1801 bufdone(bp); 1802 return (0); 1803 } 1804 } 1805 bp->b_resid = uiop->uio_resid; 1806 if (must_commit) 1807 ncl_clearcommit(vp->v_mount); 1808 bufdone(bp); 1809 return (error); 1810 } 1811 1812 /* 1813 * Used to aid in handling ftruncate() operations on the NFS client side. 1814 * Truncation creates a number of special problems for NFS. We have to 1815 * throw away VM pages and buffer cache buffers that are beyond EOF, and 1816 * we have to properly handle VM pages or (potentially dirty) buffers 1817 * that straddle the truncation point. 1818 */ 1819 1820 int 1821 ncl_meta_setsize(struct vnode *vp, struct ucred *cred, struct thread *td, u_quad_t nsize) 1822 { 1823 struct nfsnode *np = VTONFS(vp); 1824 u_quad_t tsize; 1825 int biosize = vp->v_bufobj.bo_bsize; 1826 int error = 0; 1827 1828 mtx_lock(&np->n_mtx); 1829 tsize = np->n_size; 1830 np->n_size = nsize; 1831 mtx_unlock(&np->n_mtx); 1832 1833 if (nsize < tsize) { 1834 struct buf *bp; 1835 daddr_t lbn; 1836 int bufsize; 1837 1838 /* 1839 * vtruncbuf() doesn't get the buffer overlapping the 1840 * truncation point. We may have a B_DELWRI and/or B_CACHE 1841 * buffer that now needs to be truncated. 1842 */ 1843 error = vtruncbuf(vp, cred, nsize, biosize); 1844 lbn = nsize / biosize; 1845 bufsize = nsize - (lbn * biosize); 1846 bp = nfs_getcacheblk(vp, lbn, bufsize, td); 1847 if (!bp) 1848 return EINTR; 1849 if (bp->b_dirtyoff > bp->b_bcount) 1850 bp->b_dirtyoff = bp->b_bcount; 1851 if (bp->b_dirtyend > bp->b_bcount) 1852 bp->b_dirtyend = bp->b_bcount; 1853 bp->b_flags |= B_RELBUF; /* don't leave garbage around */ 1854 brelse(bp); 1855 } else { 1856 vnode_pager_setsize(vp, nsize); 1857 } 1858 return(error); 1859 } 1860 1861
Indexes created Sun Sep 21 20:09:37 GMT 2025