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 uma_zone_t ncl_pbuf_zone; 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, long *sz) 98 { 99 struct nfsnode *np; 100 u_quad_t nsize; 101 int biosize, bcount; 102 103 np = VTONFS(vp); 104 NFSLOCKNODE(np); 105 nsize = np->n_size; 106 NFSUNLOCKNODE(np); 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 *sz = bcount; 115 return (0); 116 } 117 118 int 119 ncl_getpages(struct vop_getpages_args *ap) 120 { 121 int i, error, nextoff, size, toff, count, npages; 122 struct uio uio; 123 struct iovec iov; 124 vm_offset_t kva; 125 struct buf *bp; 126 struct vnode *vp; 127 struct thread *td; 128 struct ucred *cred; 129 struct nfsmount *nmp; 130 vm_object_t object; 131 vm_page_t *pages; 132 struct nfsnode *np; 133 134 vp = ap->a_vp; 135 np = VTONFS(vp); 136 td = curthread; 137 cred = curthread->td_ucred; 138 nmp = VFSTONFS(vp->v_mount); 139 pages = ap->a_m; 140 npages = ap->a_count; 141 142 if ((object = vp->v_object) == NULL) { 143 printf("ncl_getpages: called with non-merged cache vnode\n"); 144 return (VM_PAGER_ERROR); 145 } 146 147 if (newnfs_directio_enable && !newnfs_directio_allow_mmap) { 148 NFSLOCKNODE(np); 149 if ((np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 150 NFSUNLOCKNODE(np); 151 printf("ncl_getpages: called on non-cacheable vnode\n"); 152 return (VM_PAGER_ERROR); 153 } else 154 NFSUNLOCKNODE(np); 155 } 156 157 mtx_lock(&nmp->nm_mtx); 158 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 159 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 160 mtx_unlock(&nmp->nm_mtx); 161 /* We'll never get here for v4, because we always have fsinfo */ 162 (void)ncl_fsinfo(nmp, vp, cred, td); 163 } else 164 mtx_unlock(&nmp->nm_mtx); 165 166 if (use_buf_pager) 167 return (vfs_bio_getpages(vp, pages, npages, ap->a_rbehind, 168 ap->a_rahead, ncl_gbp_getblkno, ncl_gbp_getblksz)); 169 170 /* 171 * If the requested page is partially valid, just return it and 172 * allow the pager to zero-out the blanks. Partially valid pages 173 * can only occur at the file EOF. 174 * 175 * XXXGL: is that true for NFS, where short read can occur??? 176 */ 177 VM_OBJECT_WLOCK(object); 178 if (!vm_page_none_valid(pages[npages - 1]) && --npages == 0) 179 goto out; 180 VM_OBJECT_WUNLOCK(object); 181 182 /* 183 * We use only the kva address for the buffer, but this is extremely 184 * convenient and fast. 185 */ 186 bp = uma_zalloc(ncl_pbuf_zone, M_WAITOK); 187 188 kva = (vm_offset_t) bp->b_data; 189 pmap_qenter(kva, pages, npages); 190 VM_CNT_INC(v_vnodein); 191 VM_CNT_ADD(v_vnodepgsin, npages); 192 193 count = npages << PAGE_SHIFT; 194 iov.iov_base = (caddr_t) kva; 195 iov.iov_len = count; 196 uio.uio_iov = &iov; 197 uio.uio_iovcnt = 1; 198 uio.uio_offset = IDX_TO_OFF(pages[0]->pindex); 199 uio.uio_resid = count; 200 uio.uio_segflg = UIO_SYSSPACE; 201 uio.uio_rw = UIO_READ; 202 uio.uio_td = td; 203 204 error = ncl_readrpc(vp, &uio, cred); 205 pmap_qremove(kva, npages); 206 207 uma_zfree(ncl_pbuf_zone, bp); 208 209 if (error && (uio.uio_resid == count)) { 210 printf("ncl_getpages: error %d\n", error); 211 return (VM_PAGER_ERROR); 212 } 213 214 /* 215 * Calculate the number of bytes read and validate only that number 216 * of bytes. Note that due to pending writes, size may be 0. This 217 * does not mean that the remaining data is invalid! 218 */ 219 220 size = count - uio.uio_resid; 221 VM_OBJECT_WLOCK(object); 222 for (i = 0, toff = 0; i < npages; i++, toff = nextoff) { 223 vm_page_t m; 224 nextoff = toff + PAGE_SIZE; 225 m = pages[i]; 226 227 if (nextoff <= size) { 228 /* 229 * Read operation filled an entire page 230 */ 231 vm_page_valid(m); 232 KASSERT(m->dirty == 0, 233 ("nfs_getpages: page %p is dirty", m)); 234 } else if (size > toff) { 235 /* 236 * Read operation filled a partial page. 237 */ 238 vm_page_invalid(m); 239 vm_page_set_valid_range(m, 0, size - toff); 240 KASSERT(m->dirty == 0, 241 ("nfs_getpages: page %p is dirty", m)); 242 } else { 243 /* 244 * Read operation was short. If no error 245 * occurred we may have hit a zero-fill 246 * section. We leave valid set to 0, and page 247 * is freed by vm_page_readahead_finish() if 248 * its index is not equal to requested, or 249 * page is zeroed and set valid by 250 * vm_pager_get_pages() for requested page. 251 */ 252 ; 253 } 254 } 255 out: 256 VM_OBJECT_WUNLOCK(object); 257 if (ap->a_rbehind) 258 *ap->a_rbehind = 0; 259 if (ap->a_rahead) 260 *ap->a_rahead = 0; 261 return (VM_PAGER_OK); 262 } 263 264 /* 265 * Vnode op for VM putpages. 266 */ 267 int 268 ncl_putpages(struct vop_putpages_args *ap) 269 { 270 struct uio uio; 271 struct iovec iov; 272 int i, error, npages, count; 273 off_t offset; 274 int *rtvals; 275 struct vnode *vp; 276 struct thread *td; 277 struct ucred *cred; 278 struct nfsmount *nmp; 279 struct nfsnode *np; 280 vm_page_t *pages; 281 282 vp = ap->a_vp; 283 np = VTONFS(vp); 284 td = curthread; /* XXX */ 285 /* Set the cred to n_writecred for the write rpcs. */ 286 if (np->n_writecred != NULL) 287 cred = crhold(np->n_writecred); 288 else 289 cred = crhold(curthread->td_ucred); /* XXX */ 290 nmp = VFSTONFS(vp->v_mount); 291 pages = ap->a_m; 292 count = ap->a_count; 293 rtvals = ap->a_rtvals; 294 npages = btoc(count); 295 offset = IDX_TO_OFF(pages[0]->pindex); 296 297 mtx_lock(&nmp->nm_mtx); 298 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 299 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 300 mtx_unlock(&nmp->nm_mtx); 301 (void)ncl_fsinfo(nmp, vp, cred, td); 302 } else 303 mtx_unlock(&nmp->nm_mtx); 304 305 NFSLOCKNODE(np); 306 if (newnfs_directio_enable && !newnfs_directio_allow_mmap && 307 (np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 308 NFSUNLOCKNODE(np); 309 printf("ncl_putpages: called on noncache-able vnode\n"); 310 NFSLOCKNODE(np); 311 } 312 /* 313 * When putting pages, do not extend file past EOF. 314 */ 315 if (offset + count > np->n_size) { 316 count = np->n_size - offset; 317 if (count < 0) 318 count = 0; 319 } 320 NFSUNLOCKNODE(np); 321 322 for (i = 0; i < npages; i++) 323 rtvals[i] = VM_PAGER_ERROR; 324 325 VM_CNT_INC(v_vnodeout); 326 VM_CNT_ADD(v_vnodepgsout, count); 327 328 iov.iov_base = unmapped_buf; 329 iov.iov_len = count; 330 uio.uio_iov = &iov; 331 uio.uio_iovcnt = 1; 332 uio.uio_offset = offset; 333 uio.uio_resid = count; 334 uio.uio_segflg = UIO_NOCOPY; 335 uio.uio_rw = UIO_WRITE; 336 uio.uio_td = td; 337 338 error = VOP_WRITE(vp, &uio, vnode_pager_putpages_ioflags(ap->a_sync), 339 cred); 340 crfree(cred); 341 342 if (error == 0 || !nfs_keep_dirty_on_error) { 343 vnode_pager_undirty_pages(pages, rtvals, count - uio.uio_resid, 344 np->n_size - offset, npages * PAGE_SIZE); 345 } 346 return (rtvals[0]); 347 } 348 349 /* 350 * For nfs, cache consistency can only be maintained approximately. 351 * Although RFC1094 does not specify the criteria, the following is 352 * believed to be compatible with the reference port. 353 * For nfs: 354 * If the file's modify time on the server has changed since the 355 * last read rpc or you have written to the file, 356 * you may have lost data cache consistency with the 357 * server, so flush all of the file's data out of the cache. 358 * Then force a getattr rpc to ensure that you have up to date 359 * attributes. 360 * NB: This implies that cache data can be read when up to 361 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 362 * attributes this could be forced by setting n_attrstamp to 0 before 363 * the VOP_GETATTR() call. 364 */ 365 static inline int 366 nfs_bioread_check_cons(struct vnode *vp, struct thread *td, struct ucred *cred) 367 { 368 int error = 0; 369 struct vattr vattr; 370 struct nfsnode *np = VTONFS(vp); 371 bool old_lock; 372 373 /* 374 * Ensure the exclusove access to the node before checking 375 * whether the cache is consistent. 376 */ 377 old_lock = ncl_excl_start(vp); 378 NFSLOCKNODE(np); 379 if (np->n_flag & NMODIFIED) { 380 NFSUNLOCKNODE(np); 381 if (vp->v_type != VREG) { 382 if (vp->v_type != VDIR) 383 panic("nfs: bioread, not dir"); 384 ncl_invaldir(vp); 385 error = ncl_vinvalbuf(vp, V_SAVE | V_ALLOWCLEAN, td, 1); 386 if (error != 0) 387 goto out; 388 } 389 np->n_attrstamp = 0; 390 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 391 error = VOP_GETATTR(vp, &vattr, cred); 392 if (error) 393 goto out; 394 NFSLOCKNODE(np); 395 np->n_mtime = vattr.va_mtime; 396 NFSUNLOCKNODE(np); 397 } else { 398 NFSUNLOCKNODE(np); 399 error = VOP_GETATTR(vp, &vattr, cred); 400 if (error) 401 goto out; 402 NFSLOCKNODE(np); 403 if ((np->n_flag & NSIZECHANGED) 404 || (NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime))) { 405 NFSUNLOCKNODE(np); 406 if (vp->v_type == VDIR) 407 ncl_invaldir(vp); 408 error = ncl_vinvalbuf(vp, V_SAVE | V_ALLOWCLEAN, td, 1); 409 if (error != 0) 410 goto out; 411 NFSLOCKNODE(np); 412 np->n_mtime = vattr.va_mtime; 413 np->n_flag &= ~NSIZECHANGED; 414 } 415 NFSUNLOCKNODE(np); 416 } 417 out: 418 ncl_excl_finish(vp, old_lock); 419 return (error); 420 } 421 422 /* 423 * Vnode op for read using bio 424 */ 425 int 426 ncl_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred) 427 { 428 struct nfsnode *np = VTONFS(vp); 429 struct buf *bp, *rabp; 430 struct thread *td; 431 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 432 daddr_t lbn, rabn; 433 int biosize, bcount, error, i, n, nra, on, save2, seqcount; 434 off_t tmp_off; 435 436 KASSERT(uio->uio_rw == UIO_READ, ("ncl_read mode")); 437 if (uio->uio_resid == 0) 438 return (0); 439 if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */ 440 return (EINVAL); 441 td = uio->uio_td; 442 443 mtx_lock(&nmp->nm_mtx); 444 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 445 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 446 mtx_unlock(&nmp->nm_mtx); 447 (void)ncl_fsinfo(nmp, vp, cred, td); 448 mtx_lock(&nmp->nm_mtx); 449 } 450 if (nmp->nm_rsize == 0 || nmp->nm_readdirsize == 0) 451 (void) newnfs_iosize(nmp); 452 453 tmp_off = uio->uio_offset + uio->uio_resid; 454 if (vp->v_type != VDIR && 455 (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset)) { 456 mtx_unlock(&nmp->nm_mtx); 457 return (EFBIG); 458 } 459 mtx_unlock(&nmp->nm_mtx); 460 461 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && (vp->v_type == VREG)) 462 /* No caching/ no readaheads. Just read data into the user buffer */ 463 return ncl_readrpc(vp, uio, cred); 464 465 n = 0; 466 on = 0; 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 save2 = curthread_pflags2_set(TDP2_SBPAGES); 475 do { 476 u_quad_t nsize; 477 478 NFSLOCKNODE(np); 479 nsize = np->n_size; 480 NFSUNLOCKNODE(np); 481 482 switch (vp->v_type) { 483 case VREG: 484 NFSINCRGLOBAL(nfsstatsv1.biocache_reads); 485 lbn = uio->uio_offset / biosize; 486 on = uio->uio_offset - (lbn * biosize); 487 488 /* 489 * Start the read ahead(s), as required. 490 */ 491 if (nmp->nm_readahead > 0) { 492 for (nra = 0; nra < nmp->nm_readahead && nra < seqcount && 493 (off_t)(lbn + 1 + nra) * biosize < nsize; nra++) { 494 rabn = lbn + 1 + nra; 495 if (incore(&vp->v_bufobj, rabn) == NULL) { 496 rabp = nfs_getcacheblk(vp, rabn, biosize, td); 497 if (!rabp) { 498 error = newnfs_sigintr(nmp, td); 499 if (error == 0) 500 error = EINTR; 501 goto out; 502 } 503 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 504 rabp->b_flags |= B_ASYNC; 505 rabp->b_iocmd = BIO_READ; 506 vfs_busy_pages(rabp, 0); 507 if (ncl_asyncio(nmp, rabp, cred, td)) { 508 rabp->b_flags |= B_INVAL; 509 rabp->b_ioflags |= BIO_ERROR; 510 vfs_unbusy_pages(rabp); 511 brelse(rabp); 512 break; 513 } 514 } else { 515 brelse(rabp); 516 } 517 } 518 } 519 } 520 521 /* Note that bcount is *not* DEV_BSIZE aligned. */ 522 bcount = biosize; 523 if ((off_t)lbn * biosize >= nsize) { 524 bcount = 0; 525 } else if ((off_t)(lbn + 1) * biosize > nsize) { 526 bcount = nsize - (off_t)lbn * biosize; 527 } 528 bp = nfs_getcacheblk(vp, lbn, bcount, td); 529 530 if (!bp) { 531 error = newnfs_sigintr(nmp, td); 532 if (error == 0) 533 error = EINTR; 534 goto out; 535 } 536 537 /* 538 * If B_CACHE is not set, we must issue the read. If this 539 * fails, we return an error. 540 */ 541 542 if ((bp->b_flags & B_CACHE) == 0) { 543 bp->b_iocmd = BIO_READ; 544 vfs_busy_pages(bp, 0); 545 error = ncl_doio(vp, bp, cred, td, 0); 546 if (error) { 547 brelse(bp); 548 goto out; 549 } 550 } 551 552 /* 553 * on is the offset into the current bp. Figure out how many 554 * bytes we can copy out of the bp. Note that bcount is 555 * NOT DEV_BSIZE aligned. 556 * 557 * Then figure out how many bytes we can copy into the uio. 558 */ 559 560 n = 0; 561 if (on < bcount) 562 n = MIN((unsigned)(bcount - on), uio->uio_resid); 563 break; 564 case VLNK: 565 NFSINCRGLOBAL(nfsstatsv1.biocache_readlinks); 566 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, td); 567 if (!bp) { 568 error = newnfs_sigintr(nmp, td); 569 if (error == 0) 570 error = EINTR; 571 goto out; 572 } 573 if ((bp->b_flags & B_CACHE) == 0) { 574 bp->b_iocmd = BIO_READ; 575 vfs_busy_pages(bp, 0); 576 error = ncl_doio(vp, bp, cred, td, 0); 577 if (error) { 578 bp->b_ioflags |= BIO_ERROR; 579 brelse(bp); 580 goto out; 581 } 582 } 583 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 584 on = 0; 585 break; 586 case VDIR: 587 NFSINCRGLOBAL(nfsstatsv1.biocache_readdirs); 588 NFSLOCKNODE(np); 589 if (np->n_direofoffset 590 && uio->uio_offset >= np->n_direofoffset) { 591 NFSUNLOCKNODE(np); 592 error = 0; 593 goto out; 594 } 595 NFSUNLOCKNODE(np); 596 lbn = (uoff_t)uio->uio_offset / NFS_DIRBLKSIZ; 597 on = uio->uio_offset & (NFS_DIRBLKSIZ - 1); 598 bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, td); 599 if (!bp) { 600 error = newnfs_sigintr(nmp, td); 601 if (error == 0) 602 error = EINTR; 603 goto out; 604 } 605 if ((bp->b_flags & B_CACHE) == 0) { 606 bp->b_iocmd = BIO_READ; 607 vfs_busy_pages(bp, 0); 608 error = ncl_doio(vp, bp, cred, td, 0); 609 if (error) { 610 brelse(bp); 611 } 612 while (error == NFSERR_BAD_COOKIE) { 613 ncl_invaldir(vp); 614 error = ncl_vinvalbuf(vp, 0, td, 1); 615 616 /* 617 * Yuck! The directory has been modified on the 618 * server. The only way to get the block is by 619 * reading from the beginning to get all the 620 * offset cookies. 621 * 622 * Leave the last bp intact unless there is an error. 623 * Loop back up to the while if the error is another 624 * NFSERR_BAD_COOKIE (double yuch!). 625 */ 626 for (i = 0; i <= lbn && !error; i++) { 627 NFSLOCKNODE(np); 628 if (np->n_direofoffset 629 && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset) { 630 NFSUNLOCKNODE(np); 631 error = 0; 632 goto out; 633 } 634 NFSUNLOCKNODE(np); 635 bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, td); 636 if (!bp) { 637 error = newnfs_sigintr(nmp, td); 638 if (error == 0) 639 error = EINTR; 640 goto out; 641 } 642 if ((bp->b_flags & B_CACHE) == 0) { 643 bp->b_iocmd = BIO_READ; 644 vfs_busy_pages(bp, 0); 645 error = ncl_doio(vp, bp, cred, td, 0); 646 /* 647 * no error + B_INVAL == directory EOF, 648 * use the block. 649 */ 650 if (error == 0 && (bp->b_flags & B_INVAL)) 651 break; 652 } 653 /* 654 * An error will throw away the block and the 655 * for loop will break out. If no error and this 656 * is not the block we want, we throw away the 657 * block and go for the next one via the for loop. 658 */ 659 if (error || i < lbn) 660 brelse(bp); 661 } 662 } 663 /* 664 * The above while is repeated if we hit another cookie 665 * error. If we hit an error and it wasn't a cookie error, 666 * we give up. 667 */ 668 if (error) 669 goto out; 670 } 671 672 /* 673 * If not eof and read aheads are enabled, start one. 674 * (You need the current block first, so that you have the 675 * directory offset cookie of the next block.) 676 */ 677 NFSLOCKNODE(np); 678 if (nmp->nm_readahead > 0 && 679 (bp->b_flags & B_INVAL) == 0 && 680 (np->n_direofoffset == 0 || 681 (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) && 682 incore(&vp->v_bufobj, lbn + 1) == NULL) { 683 NFSUNLOCKNODE(np); 684 rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td); 685 if (rabp) { 686 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 687 rabp->b_flags |= B_ASYNC; 688 rabp->b_iocmd = BIO_READ; 689 vfs_busy_pages(rabp, 0); 690 if (ncl_asyncio(nmp, rabp, cred, td)) { 691 rabp->b_flags |= B_INVAL; 692 rabp->b_ioflags |= BIO_ERROR; 693 vfs_unbusy_pages(rabp); 694 brelse(rabp); 695 } 696 } else { 697 brelse(rabp); 698 } 699 } 700 NFSLOCKNODE(np); 701 } 702 /* 703 * Unlike VREG files, whos buffer size ( bp->b_bcount ) is 704 * chopped for the EOF condition, we cannot tell how large 705 * NFS directories are going to be until we hit EOF. So 706 * an NFS directory buffer is *not* chopped to its EOF. Now, 707 * it just so happens that b_resid will effectively chop it 708 * to EOF. *BUT* this information is lost if the buffer goes 709 * away and is reconstituted into a B_CACHE state ( due to 710 * being VMIO ) later. So we keep track of the directory eof 711 * in np->n_direofoffset and chop it off as an extra step 712 * right here. 713 */ 714 n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on); 715 if (np->n_direofoffset && n > np->n_direofoffset - uio->uio_offset) 716 n = np->n_direofoffset - uio->uio_offset; 717 NFSUNLOCKNODE(np); 718 break; 719 default: 720 printf(" ncl_bioread: type %x unexpected\n", vp->v_type); 721 bp = NULL; 722 break; 723 } 724 725 if (n > 0) { 726 error = vn_io_fault_uiomove(bp->b_data + on, (int)n, uio); 727 } 728 if (vp->v_type == VLNK) 729 n = 0; 730 if (bp != NULL) 731 brelse(bp); 732 } while (error == 0 && uio->uio_resid > 0 && n > 0); 733 out: 734 curthread_pflags2_restore(save2); 735 if ((curthread->td_pflags2 & TDP2_SBPAGES) == 0) { 736 NFSLOCKNODE(np); 737 ncl_pager_setsize(vp, NULL); 738 } 739 return (error); 740 } 741 742 /* 743 * The NFS write path cannot handle iovecs with len > 1. So we need to 744 * break up iovecs accordingly (restricting them to wsize). 745 * For the SYNC case, we can do this with 1 copy (user buffer -> mbuf). 746 * For the ASYNC case, 2 copies are needed. The first a copy from the 747 * user buffer to a staging buffer and then a second copy from the staging 748 * buffer to mbufs. This can be optimized by copying from the user buffer 749 * directly into mbufs and passing the chain down, but that requires a 750 * fair amount of re-working of the relevant codepaths (and can be done 751 * later). 752 */ 753 static int 754 nfs_directio_write(vp, uiop, cred, ioflag) 755 struct vnode *vp; 756 struct uio *uiop; 757 struct ucred *cred; 758 int ioflag; 759 { 760 int error; 761 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 762 struct thread *td = uiop->uio_td; 763 int size; 764 int wsize; 765 766 mtx_lock(&nmp->nm_mtx); 767 wsize = nmp->nm_wsize; 768 mtx_unlock(&nmp->nm_mtx); 769 if (ioflag & IO_SYNC) { 770 int iomode, must_commit; 771 struct uio uio; 772 struct iovec iov; 773 do_sync: 774 while (uiop->uio_resid > 0) { 775 size = MIN(uiop->uio_resid, wsize); 776 size = MIN(uiop->uio_iov->iov_len, size); 777 iov.iov_base = uiop->uio_iov->iov_base; 778 iov.iov_len = size; 779 uio.uio_iov = &iov; 780 uio.uio_iovcnt = 1; 781 uio.uio_offset = uiop->uio_offset; 782 uio.uio_resid = size; 783 uio.uio_segflg = UIO_USERSPACE; 784 uio.uio_rw = UIO_WRITE; 785 uio.uio_td = td; 786 iomode = NFSWRITE_FILESYNC; 787 /* 788 * When doing direct I/O we do not care if the 789 * server's write verifier has changed, but we 790 * do not want to update the verifier if it has 791 * changed, since that hides the change from 792 * writes being done through the buffer cache. 793 * By passing must_commit in set to two, the code 794 * in nfsrpc_writerpc() will not update the 795 * verifier on the mount point. 796 */ 797 must_commit = 2; 798 error = ncl_writerpc(vp, &uio, cred, &iomode, 799 &must_commit, 0); 800 KASSERT((must_commit == 2), 801 ("ncl_directio_write: Updated write verifier")); 802 if (error) 803 return (error); 804 if (iomode != NFSWRITE_FILESYNC) 805 printf("nfs_directio_write: Broken server " 806 "did not reply FILE_SYNC\n"); 807 uiop->uio_offset += size; 808 uiop->uio_resid -= size; 809 if (uiop->uio_iov->iov_len <= size) { 810 uiop->uio_iovcnt--; 811 uiop->uio_iov++; 812 } else { 813 uiop->uio_iov->iov_base = 814 (char *)uiop->uio_iov->iov_base + size; 815 uiop->uio_iov->iov_len -= size; 816 } 817 } 818 } else { 819 struct uio *t_uio; 820 struct iovec *t_iov; 821 struct buf *bp; 822 823 /* 824 * Break up the write into blocksize chunks and hand these 825 * over to nfsiod's for write back. 826 * Unfortunately, this incurs a copy of the data. Since 827 * the user could modify the buffer before the write is 828 * initiated. 829 * 830 * The obvious optimization here is that one of the 2 copies 831 * in the async write path can be eliminated by copying the 832 * data here directly into mbufs and passing the mbuf chain 833 * down. But that will require a fair amount of re-working 834 * of the code and can be done if there's enough interest 835 * in NFS directio access. 836 */ 837 while (uiop->uio_resid > 0) { 838 size = MIN(uiop->uio_resid, wsize); 839 size = MIN(uiop->uio_iov->iov_len, size); 840 bp = uma_zalloc(ncl_pbuf_zone, M_WAITOK); 841 t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK); 842 t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK); 843 t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK); 844 t_iov->iov_len = size; 845 t_uio->uio_iov = t_iov; 846 t_uio->uio_iovcnt = 1; 847 t_uio->uio_offset = uiop->uio_offset; 848 t_uio->uio_resid = size; 849 t_uio->uio_segflg = UIO_SYSSPACE; 850 t_uio->uio_rw = UIO_WRITE; 851 t_uio->uio_td = td; 852 KASSERT(uiop->uio_segflg == UIO_USERSPACE || 853 uiop->uio_segflg == UIO_SYSSPACE, 854 ("nfs_directio_write: Bad uio_segflg")); 855 if (uiop->uio_segflg == UIO_USERSPACE) { 856 error = copyin(uiop->uio_iov->iov_base, 857 t_iov->iov_base, size); 858 if (error != 0) 859 goto err_free; 860 } else 861 /* 862 * UIO_SYSSPACE may never happen, but handle 863 * it just in case it does. 864 */ 865 bcopy(uiop->uio_iov->iov_base, t_iov->iov_base, 866 size); 867 bp->b_flags |= B_DIRECT; 868 bp->b_iocmd = BIO_WRITE; 869 if (cred != NOCRED) { 870 crhold(cred); 871 bp->b_wcred = cred; 872 } else 873 bp->b_wcred = NOCRED; 874 bp->b_caller1 = (void *)t_uio; 875 bp->b_vp = vp; 876 error = ncl_asyncio(nmp, bp, NOCRED, td); 877 err_free: 878 if (error) { 879 free(t_iov->iov_base, M_NFSDIRECTIO); 880 free(t_iov, M_NFSDIRECTIO); 881 free(t_uio, M_NFSDIRECTIO); 882 bp->b_vp = NULL; 883 uma_zfree(ncl_pbuf_zone, bp); 884 if (error == EINTR) 885 return (error); 886 goto do_sync; 887 } 888 uiop->uio_offset += size; 889 uiop->uio_resid -= size; 890 if (uiop->uio_iov->iov_len <= size) { 891 uiop->uio_iovcnt--; 892 uiop->uio_iov++; 893 } else { 894 uiop->uio_iov->iov_base = 895 (char *)uiop->uio_iov->iov_base + size; 896 uiop->uio_iov->iov_len -= size; 897 } 898 } 899 } 900 return (0); 901 } 902 903 /* 904 * Vnode op for write using bio 905 */ 906 int 907 ncl_write(struct vop_write_args *ap) 908 { 909 int biosize; 910 struct uio *uio = ap->a_uio; 911 struct thread *td = uio->uio_td; 912 struct vnode *vp = ap->a_vp; 913 struct nfsnode *np = VTONFS(vp); 914 struct ucred *cred = ap->a_cred; 915 int ioflag = ap->a_ioflag; 916 struct buf *bp; 917 struct vattr vattr; 918 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 919 daddr_t lbn; 920 int bcount, noncontig_write, obcount; 921 int bp_cached, n, on, error = 0, error1, save2, wouldcommit; 922 size_t orig_resid, local_resid; 923 off_t orig_size, tmp_off; 924 struct timespec ts; 925 926 KASSERT(uio->uio_rw == UIO_WRITE, ("ncl_write mode")); 927 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 928 ("ncl_write proc")); 929 if (vp->v_type != VREG) 930 return (EIO); 931 NFSLOCKNODE(np); 932 if (np->n_flag & NWRITEERR) { 933 np->n_flag &= ~NWRITEERR; 934 NFSUNLOCKNODE(np); 935 return (np->n_error); 936 } else 937 NFSUNLOCKNODE(np); 938 mtx_lock(&nmp->nm_mtx); 939 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 940 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 941 mtx_unlock(&nmp->nm_mtx); 942 (void)ncl_fsinfo(nmp, vp, cred, td); 943 mtx_lock(&nmp->nm_mtx); 944 } 945 if (nmp->nm_wsize == 0) 946 (void) newnfs_iosize(nmp); 947 mtx_unlock(&nmp->nm_mtx); 948 949 /* 950 * Synchronously flush pending buffers if we are in synchronous 951 * mode or if we are appending. 952 */ 953 if (ioflag & (IO_APPEND | IO_SYNC)) { 954 NFSLOCKNODE(np); 955 if (np->n_flag & NMODIFIED) { 956 NFSUNLOCKNODE(np); 957 #ifdef notyet /* Needs matching nonblock semantics elsewhere, too. */ 958 /* 959 * Require non-blocking, synchronous writes to 960 * dirty files to inform the program it needs 961 * to fsync(2) explicitly. 962 */ 963 if (ioflag & IO_NDELAY) 964 return (EAGAIN); 965 #endif 966 np->n_attrstamp = 0; 967 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 968 error = ncl_vinvalbuf(vp, V_SAVE | ((ioflag & 969 IO_VMIO) != 0 ? V_VMIO : 0), td, 1); 970 if (error != 0) 971 return (error); 972 } else 973 NFSUNLOCKNODE(np); 974 } 975 976 orig_resid = uio->uio_resid; 977 NFSLOCKNODE(np); 978 orig_size = np->n_size; 979 NFSUNLOCKNODE(np); 980 981 /* 982 * If IO_APPEND then load uio_offset. We restart here if we cannot 983 * get the append lock. 984 */ 985 if (ioflag & IO_APPEND) { 986 np->n_attrstamp = 0; 987 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 988 error = VOP_GETATTR(vp, &vattr, cred); 989 if (error) 990 return (error); 991 NFSLOCKNODE(np); 992 uio->uio_offset = np->n_size; 993 NFSUNLOCKNODE(np); 994 } 995 996 if (uio->uio_offset < 0) 997 return (EINVAL); 998 tmp_off = uio->uio_offset + uio->uio_resid; 999 if (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset) 1000 return (EFBIG); 1001 if (uio->uio_resid == 0) 1002 return (0); 1003 1004 /* 1005 * If the file in not mmap()'d, do IO_APPEND writing via a 1006 * synchronous direct write. This can result in a significant 1007 * performance improvement. 1008 * If the file is mmap()'d, this cannot be done, since there 1009 * is no way to maintain consistency between the file on the 1010 * NFS server and the file's mmap()'d pages. 1011 */ 1012 NFSLOCKNODE(np); 1013 if (vp->v_type == VREG && ((newnfs_directio_enable && (ioflag & 1014 IO_DIRECT)) || ((ioflag & IO_APPEND) && 1015 (vp->v_object == NULL || !vm_object_is_active(vp->v_object))))) { 1016 NFSUNLOCKNODE(np); 1017 if ((ioflag & IO_APPEND) != 0) 1018 ioflag |= IO_SYNC; 1019 return nfs_directio_write(vp, uio, cred, ioflag); 1020 } 1021 NFSUNLOCKNODE(np); 1022 1023 /* 1024 * Maybe this should be above the vnode op call, but so long as 1025 * file servers have no limits, i don't think it matters 1026 */ 1027 if (vn_rlimit_fsize(vp, uio, td)) 1028 return (EFBIG); 1029 1030 save2 = curthread_pflags2_set(TDP2_SBPAGES); 1031 biosize = vp->v_bufobj.bo_bsize; 1032 /* 1033 * Find all of this file's B_NEEDCOMMIT buffers. If our writes 1034 * would exceed the local maximum per-file write commit size when 1035 * combined with those, we must decide whether to flush, 1036 * go synchronous, or return error. We don't bother checking 1037 * IO_UNIT -- we just make all writes atomic anyway, as there's 1038 * no point optimizing for something that really won't ever happen. 1039 */ 1040 wouldcommit = 0; 1041 if (!(ioflag & IO_SYNC)) { 1042 int nflag; 1043 1044 NFSLOCKNODE(np); 1045 nflag = np->n_flag; 1046 NFSUNLOCKNODE(np); 1047 if (nflag & NMODIFIED) { 1048 BO_LOCK(&vp->v_bufobj); 1049 if (vp->v_bufobj.bo_dirty.bv_cnt != 0) { 1050 TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd, 1051 b_bobufs) { 1052 if (bp->b_flags & B_NEEDCOMMIT) 1053 wouldcommit += bp->b_bcount; 1054 } 1055 } 1056 BO_UNLOCK(&vp->v_bufobj); 1057 } 1058 } 1059 1060 do { 1061 if (!(ioflag & IO_SYNC)) { 1062 wouldcommit += biosize; 1063 if (wouldcommit > nmp->nm_wcommitsize) { 1064 np->n_attrstamp = 0; 1065 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 1066 error = ncl_vinvalbuf(vp, V_SAVE | ((ioflag & 1067 IO_VMIO) != 0 ? V_VMIO : 0), td, 1); 1068 if (error != 0) 1069 goto out; 1070 wouldcommit = biosize; 1071 } 1072 } 1073 1074 NFSINCRGLOBAL(nfsstatsv1.biocache_writes); 1075 lbn = uio->uio_offset / biosize; 1076 on = uio->uio_offset - (lbn * biosize); 1077 n = MIN((unsigned)(biosize - on), uio->uio_resid); 1078 again: 1079 /* 1080 * Handle direct append and file extension cases, calculate 1081 * unaligned buffer size. 1082 */ 1083 NFSLOCKNODE(np); 1084 if ((np->n_flag & NHASBEENLOCKED) == 0 && 1085 (nmp->nm_flag & NFSMNT_NONCONTIGWR) != 0) 1086 noncontig_write = 1; 1087 else 1088 noncontig_write = 0; 1089 if ((uio->uio_offset == np->n_size || 1090 (noncontig_write != 0 && 1091 lbn == (np->n_size / biosize) && 1092 uio->uio_offset + n > np->n_size)) && n) { 1093 NFSUNLOCKNODE(np); 1094 /* 1095 * Get the buffer (in its pre-append state to maintain 1096 * B_CACHE if it was previously set). Resize the 1097 * nfsnode after we have locked the buffer to prevent 1098 * readers from reading garbage. 1099 */ 1100 obcount = np->n_size - (lbn * biosize); 1101 bp = nfs_getcacheblk(vp, lbn, obcount, td); 1102 1103 if (bp != NULL) { 1104 long save; 1105 1106 NFSLOCKNODE(np); 1107 np->n_size = uio->uio_offset + n; 1108 np->n_flag |= NMODIFIED; 1109 np->n_flag &= ~NVNSETSZSKIP; 1110 vnode_pager_setsize(vp, np->n_size); 1111 NFSUNLOCKNODE(np); 1112 1113 save = bp->b_flags & B_CACHE; 1114 bcount = on + n; 1115 allocbuf(bp, bcount); 1116 bp->b_flags |= save; 1117 if (noncontig_write != 0 && on > obcount) 1118 vfs_bio_bzero_buf(bp, obcount, on - 1119 obcount); 1120 } 1121 } else { 1122 /* 1123 * Obtain the locked cache block first, and then 1124 * adjust the file's size as appropriate. 1125 */ 1126 bcount = on + n; 1127 if ((off_t)lbn * biosize + bcount < np->n_size) { 1128 if ((off_t)(lbn + 1) * biosize < np->n_size) 1129 bcount = biosize; 1130 else 1131 bcount = np->n_size - (off_t)lbn * biosize; 1132 } 1133 NFSUNLOCKNODE(np); 1134 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1135 NFSLOCKNODE(np); 1136 if (uio->uio_offset + n > np->n_size) { 1137 np->n_size = uio->uio_offset + n; 1138 np->n_flag |= NMODIFIED; 1139 np->n_flag &= ~NVNSETSZSKIP; 1140 vnode_pager_setsize(vp, np->n_size); 1141 } 1142 NFSUNLOCKNODE(np); 1143 } 1144 1145 if (!bp) { 1146 error = newnfs_sigintr(nmp, td); 1147 if (!error) 1148 error = EINTR; 1149 break; 1150 } 1151 1152 /* 1153 * Issue a READ if B_CACHE is not set. In special-append 1154 * mode, B_CACHE is based on the buffer prior to the write 1155 * op and is typically set, avoiding the read. If a read 1156 * is required in special append mode, the server will 1157 * probably send us a short-read since we extended the file 1158 * on our end, resulting in b_resid == 0 and, thusly, 1159 * B_CACHE getting set. 1160 * 1161 * We can also avoid issuing the read if the write covers 1162 * the entire buffer. We have to make sure the buffer state 1163 * is reasonable in this case since we will not be initiating 1164 * I/O. See the comments in kern/vfs_bio.c's getblk() for 1165 * more information. 1166 * 1167 * B_CACHE may also be set due to the buffer being cached 1168 * normally. 1169 */ 1170 1171 bp_cached = 1; 1172 if (on == 0 && n == bcount) { 1173 if ((bp->b_flags & B_CACHE) == 0) 1174 bp_cached = 0; 1175 bp->b_flags |= B_CACHE; 1176 bp->b_flags &= ~B_INVAL; 1177 bp->b_ioflags &= ~BIO_ERROR; 1178 } 1179 1180 if ((bp->b_flags & B_CACHE) == 0) { 1181 bp->b_iocmd = BIO_READ; 1182 vfs_busy_pages(bp, 0); 1183 error = ncl_doio(vp, bp, cred, td, 0); 1184 if (error) { 1185 brelse(bp); 1186 break; 1187 } 1188 } 1189 if (bp->b_wcred == NOCRED) 1190 bp->b_wcred = crhold(cred); 1191 NFSLOCKNODE(np); 1192 np->n_flag |= NMODIFIED; 1193 NFSUNLOCKNODE(np); 1194 1195 /* 1196 * If dirtyend exceeds file size, chop it down. This should 1197 * not normally occur but there is an append race where it 1198 * might occur XXX, so we log it. 1199 * 1200 * If the chopping creates a reverse-indexed or degenerate 1201 * situation with dirtyoff/end, we 0 both of them. 1202 */ 1203 1204 if (bp->b_dirtyend > bcount) { 1205 printf("NFS append race @%lx:%d\n", 1206 (long)bp->b_blkno * DEV_BSIZE, 1207 bp->b_dirtyend - bcount); 1208 bp->b_dirtyend = bcount; 1209 } 1210 1211 if (bp->b_dirtyoff >= bp->b_dirtyend) 1212 bp->b_dirtyoff = bp->b_dirtyend = 0; 1213 1214 /* 1215 * If the new write will leave a contiguous dirty 1216 * area, just update the b_dirtyoff and b_dirtyend, 1217 * otherwise force a write rpc of the old dirty area. 1218 * 1219 * If there has been a file lock applied to this file 1220 * or vfs.nfs.old_noncontig_writing is set, do the following: 1221 * While it is possible to merge discontiguous writes due to 1222 * our having a B_CACHE buffer ( and thus valid read data 1223 * for the hole), we don't because it could lead to 1224 * significant cache coherency problems with multiple clients, 1225 * especially if locking is implemented later on. 1226 * 1227 * If vfs.nfs.old_noncontig_writing is not set and there has 1228 * not been file locking done on this file: 1229 * Relax coherency a bit for the sake of performance and 1230 * expand the current dirty region to contain the new 1231 * write even if it means we mark some non-dirty data as 1232 * dirty. 1233 */ 1234 1235 if (noncontig_write == 0 && bp->b_dirtyend > 0 && 1236 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 1237 if (bwrite(bp) == EINTR) { 1238 error = EINTR; 1239 break; 1240 } 1241 goto again; 1242 } 1243 1244 local_resid = uio->uio_resid; 1245 error = vn_io_fault_uiomove((char *)bp->b_data + on, n, uio); 1246 1247 if (error != 0 && !bp_cached) { 1248 /* 1249 * This block has no other content then what 1250 * possibly was written by the faulty uiomove. 1251 * Release it, forgetting the data pages, to 1252 * prevent the leak of uninitialized data to 1253 * usermode. 1254 */ 1255 bp->b_ioflags |= BIO_ERROR; 1256 brelse(bp); 1257 uio->uio_offset -= local_resid - uio->uio_resid; 1258 uio->uio_resid = local_resid; 1259 break; 1260 } 1261 1262 /* 1263 * Since this block is being modified, it must be written 1264 * again and not just committed. Since write clustering does 1265 * not work for the stage 1 data write, only the stage 2 1266 * commit rpc, we have to clear B_CLUSTEROK as well. 1267 */ 1268 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1269 1270 /* 1271 * Get the partial update on the progress made from 1272 * uiomove, if an error occurred. 1273 */ 1274 if (error != 0) 1275 n = local_resid - uio->uio_resid; 1276 1277 /* 1278 * Only update dirtyoff/dirtyend if not a degenerate 1279 * condition. 1280 */ 1281 if (n > 0) { 1282 if (bp->b_dirtyend > 0) { 1283 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 1284 bp->b_dirtyend = max((on + n), bp->b_dirtyend); 1285 } else { 1286 bp->b_dirtyoff = on; 1287 bp->b_dirtyend = on + n; 1288 } 1289 vfs_bio_set_valid(bp, on, n); 1290 } 1291 1292 /* 1293 * If IO_SYNC do bwrite(). 1294 * 1295 * IO_INVAL appears to be unused. The idea appears to be 1296 * to turn off caching in this case. Very odd. XXX 1297 */ 1298 if ((ioflag & IO_SYNC)) { 1299 if (ioflag & IO_INVAL) 1300 bp->b_flags |= B_NOCACHE; 1301 error1 = bwrite(bp); 1302 if (error1 != 0) { 1303 if (error == 0) 1304 error = error1; 1305 break; 1306 } 1307 } else if ((n + on) == biosize || (ioflag & IO_ASYNC) != 0) { 1308 bp->b_flags |= B_ASYNC; 1309 (void) ncl_writebp(bp, 0, NULL); 1310 } else { 1311 bdwrite(bp); 1312 } 1313 1314 if (error != 0) 1315 break; 1316 } while (uio->uio_resid > 0 && n > 0); 1317 1318 if (error == 0) { 1319 nanouptime(&ts); 1320 NFSLOCKNODE(np); 1321 np->n_localmodtime = ts; 1322 NFSUNLOCKNODE(np); 1323 } else { 1324 if (ioflag & IO_UNIT) { 1325 VATTR_NULL(&vattr); 1326 vattr.va_size = orig_size; 1327 /* IO_SYNC is handled implicitely */ 1328 (void)VOP_SETATTR(vp, &vattr, cred); 1329 uio->uio_offset -= orig_resid - uio->uio_resid; 1330 uio->uio_resid = orig_resid; 1331 } 1332 } 1333 1334 out: 1335 curthread_pflags2_restore(save2); 1336 return (error); 1337 } 1338 1339 /* 1340 * Get an nfs cache block. 1341 * 1342 * Allocate a new one if the block isn't currently in the cache 1343 * and return the block marked busy. If the calling process is 1344 * interrupted by a signal for an interruptible mount point, return 1345 * NULL. 1346 * 1347 * The caller must carefully deal with the possible B_INVAL state of 1348 * the buffer. ncl_doio() clears B_INVAL (and ncl_asyncio() clears it 1349 * indirectly), so synchronous reads can be issued without worrying about 1350 * the B_INVAL state. We have to be a little more careful when dealing 1351 * with writes (see comments in nfs_write()) when extending a file past 1352 * its EOF. 1353 */ 1354 static struct buf * 1355 nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td) 1356 { 1357 struct buf *bp; 1358 struct mount *mp; 1359 struct nfsmount *nmp; 1360 1361 mp = vp->v_mount; 1362 nmp = VFSTONFS(mp); 1363 1364 if (nmp->nm_flag & NFSMNT_INT) { 1365 sigset_t oldset; 1366 1367 newnfs_set_sigmask(td, &oldset); 1368 bp = getblk(vp, bn, size, PCATCH, 0, 0); 1369 newnfs_restore_sigmask(td, &oldset); 1370 while (bp == NULL) { 1371 if (newnfs_sigintr(nmp, td)) 1372 return (NULL); 1373 bp = getblk(vp, bn, size, 0, 2 * hz, 0); 1374 } 1375 } else { 1376 bp = getblk(vp, bn, size, 0, 0, 0); 1377 } 1378 1379 if (vp->v_type == VREG) 1380 bp->b_blkno = bn * (vp->v_bufobj.bo_bsize / DEV_BSIZE); 1381 return (bp); 1382 } 1383 1384 /* 1385 * Flush and invalidate all dirty buffers. If another process is already 1386 * doing the flush, just wait for completion. 1387 */ 1388 int 1389 ncl_vinvalbuf(struct vnode *vp, int flags, struct thread *td, int intrflg) 1390 { 1391 struct nfsnode *np = VTONFS(vp); 1392 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1393 int error = 0, slpflag, slptimeo; 1394 bool old_lock; 1395 struct timespec ts; 1396 1397 ASSERT_VOP_LOCKED(vp, "ncl_vinvalbuf"); 1398 1399 if ((nmp->nm_flag & NFSMNT_INT) == 0) 1400 intrflg = 0; 1401 if (NFSCL_FORCEDISM(nmp->nm_mountp)) 1402 intrflg = 1; 1403 if (intrflg) { 1404 slpflag = PCATCH; 1405 slptimeo = 2 * hz; 1406 } else { 1407 slpflag = 0; 1408 slptimeo = 0; 1409 } 1410 1411 old_lock = ncl_excl_start(vp); 1412 if (old_lock) 1413 flags |= V_ALLOWCLEAN; 1414 1415 /* 1416 * Now, flush as required. 1417 */ 1418 if ((flags & (V_SAVE | V_VMIO)) == V_SAVE && 1419 vp->v_bufobj.bo_object != NULL) { 1420 VM_OBJECT_WLOCK(vp->v_bufobj.bo_object); 1421 vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC); 1422 VM_OBJECT_WUNLOCK(vp->v_bufobj.bo_object); 1423 /* 1424 * If the page clean was interrupted, fail the invalidation. 1425 * Not doing so, we run the risk of losing dirty pages in the 1426 * vinvalbuf() call below. 1427 */ 1428 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1429 goto out; 1430 } 1431 1432 error = vinvalbuf(vp, flags, slpflag, 0); 1433 while (error) { 1434 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1435 goto out; 1436 error = vinvalbuf(vp, flags, 0, slptimeo); 1437 } 1438 if (NFSHASPNFS(nmp)) { 1439 nfscl_layoutcommit(vp, td); 1440 nanouptime(&ts); 1441 /* 1442 * Invalidate the attribute cache, since writes to a DS 1443 * won't update the size attribute. 1444 */ 1445 NFSLOCKNODE(np); 1446 np->n_attrstamp = 0; 1447 } else { 1448 nanouptime(&ts); 1449 NFSLOCKNODE(np); 1450 } 1451 if (np->n_directio_asyncwr == 0 && (np->n_flag & NMODIFIED) != 0) { 1452 np->n_localmodtime = ts; 1453 np->n_flag &= ~NMODIFIED; 1454 } 1455 NFSUNLOCKNODE(np); 1456 out: 1457 ncl_excl_finish(vp, old_lock); 1458 return error; 1459 } 1460 1461 /* 1462 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 1463 * This is mainly to avoid queueing async I/O requests when the nfsiods 1464 * are all hung on a dead server. 1465 * 1466 * Note: ncl_asyncio() does not clear (BIO_ERROR|B_INVAL) but when the bp 1467 * is eventually dequeued by the async daemon, ncl_doio() *will*. 1468 */ 1469 int 1470 ncl_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td) 1471 { 1472 int iod; 1473 int gotiod; 1474 int slpflag = 0; 1475 int slptimeo = 0; 1476 int error, error2; 1477 1478 /* 1479 * Commits are usually short and sweet so lets save some cpu and 1480 * leave the async daemons for more important rpc's (such as reads 1481 * and writes). 1482 * 1483 * Readdirplus RPCs do vget()s to acquire the vnodes for entries 1484 * in the directory in order to update attributes. This can deadlock 1485 * with another thread that is waiting for async I/O to be done by 1486 * an nfsiod thread while holding a lock on one of these vnodes. 1487 * To avoid this deadlock, don't allow the async nfsiod threads to 1488 * perform Readdirplus RPCs. 1489 */ 1490 NFSLOCKIOD(); 1491 if ((bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) && 1492 (nmp->nm_bufqiods > ncl_numasync / 2)) || 1493 (bp->b_vp->v_type == VDIR && (nmp->nm_flag & NFSMNT_RDIRPLUS))) { 1494 NFSUNLOCKIOD(); 1495 return(EIO); 1496 } 1497 again: 1498 if (nmp->nm_flag & NFSMNT_INT) 1499 slpflag = PCATCH; 1500 gotiod = FALSE; 1501 1502 /* 1503 * Find a free iod to process this request. 1504 */ 1505 for (iod = 0; iod < ncl_numasync; iod++) 1506 if (ncl_iodwant[iod] == NFSIOD_AVAILABLE) { 1507 gotiod = TRUE; 1508 break; 1509 } 1510 1511 /* 1512 * Try to create one if none are free. 1513 */ 1514 if (!gotiod) 1515 ncl_nfsiodnew(); 1516 else { 1517 /* 1518 * Found one, so wake it up and tell it which 1519 * mount to process. 1520 */ 1521 NFS_DPF(ASYNCIO, ("ncl_asyncio: waking iod %d for mount %p\n", 1522 iod, nmp)); 1523 ncl_iodwant[iod] = NFSIOD_NOT_AVAILABLE; 1524 ncl_iodmount[iod] = nmp; 1525 nmp->nm_bufqiods++; 1526 wakeup(&ncl_iodwant[iod]); 1527 } 1528 1529 /* 1530 * If none are free, we may already have an iod working on this mount 1531 * point. If so, it will process our request. 1532 */ 1533 if (!gotiod) { 1534 if (nmp->nm_bufqiods > 0) { 1535 NFS_DPF(ASYNCIO, 1536 ("ncl_asyncio: %d iods are already processing mount %p\n", 1537 nmp->nm_bufqiods, nmp)); 1538 gotiod = TRUE; 1539 } 1540 } 1541 1542 /* 1543 * If we have an iod which can process the request, then queue 1544 * the buffer. 1545 */ 1546 if (gotiod) { 1547 /* 1548 * Ensure that the queue never grows too large. We still want 1549 * to asynchronize so we block rather then return EIO. 1550 */ 1551 while (nmp->nm_bufqlen >= 2*ncl_numasync) { 1552 NFS_DPF(ASYNCIO, 1553 ("ncl_asyncio: waiting for mount %p queue to drain\n", nmp)); 1554 nmp->nm_bufqwant = TRUE; 1555 error = newnfs_msleep(td, &nmp->nm_bufq, 1556 &ncl_iod_mutex, slpflag | PRIBIO, "nfsaio", 1557 slptimeo); 1558 if (error) { 1559 error2 = newnfs_sigintr(nmp, td); 1560 if (error2) { 1561 NFSUNLOCKIOD(); 1562 return (error2); 1563 } 1564 if (slpflag == PCATCH) { 1565 slpflag = 0; 1566 slptimeo = 2 * hz; 1567 } 1568 } 1569 /* 1570 * We might have lost our iod while sleeping, 1571 * so check and loop if necessary. 1572 */ 1573 goto again; 1574 } 1575 1576 /* We might have lost our nfsiod */ 1577 if (nmp->nm_bufqiods == 0) { 1578 NFS_DPF(ASYNCIO, 1579 ("ncl_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); 1580 goto again; 1581 } 1582 1583 if (bp->b_iocmd == BIO_READ) { 1584 if (bp->b_rcred == NOCRED && cred != NOCRED) 1585 bp->b_rcred = crhold(cred); 1586 } else { 1587 if (bp->b_wcred == NOCRED && cred != NOCRED) 1588 bp->b_wcred = crhold(cred); 1589 } 1590 1591 if (bp->b_flags & B_REMFREE) 1592 bremfreef(bp); 1593 BUF_KERNPROC(bp); 1594 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 1595 nmp->nm_bufqlen++; 1596 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1597 NFSLOCKNODE(VTONFS(bp->b_vp)); 1598 VTONFS(bp->b_vp)->n_flag |= NMODIFIED; 1599 VTONFS(bp->b_vp)->n_directio_asyncwr++; 1600 NFSUNLOCKNODE(VTONFS(bp->b_vp)); 1601 } 1602 NFSUNLOCKIOD(); 1603 return (0); 1604 } 1605 1606 NFSUNLOCKIOD(); 1607 1608 /* 1609 * All the iods are busy on other mounts, so return EIO to 1610 * force the caller to process the i/o synchronously. 1611 */ 1612 NFS_DPF(ASYNCIO, ("ncl_asyncio: no iods available, i/o is synchronous\n")); 1613 return (EIO); 1614 } 1615 1616 void 1617 ncl_doio_directwrite(struct buf *bp) 1618 { 1619 int iomode, must_commit; 1620 struct uio *uiop = (struct uio *)bp->b_caller1; 1621 char *iov_base = uiop->uio_iov->iov_base; 1622 1623 iomode = NFSWRITE_FILESYNC; 1624 uiop->uio_td = NULL; /* NULL since we're in nfsiod */ 1625 /* 1626 * When doing direct I/O we do not care if the 1627 * server's write verifier has changed, but we 1628 * do not want to update the verifier if it has 1629 * changed, since that hides the change from 1630 * writes being done through the buffer cache. 1631 * By passing must_commit in set to two, the code 1632 * in nfsrpc_writerpc() will not update the 1633 * verifier on the mount point. 1634 */ 1635 must_commit = 2; 1636 ncl_writerpc(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit, 0); 1637 KASSERT((must_commit == 2), ("ncl_doio_directwrite: Updated write" 1638 " verifier")); 1639 if (iomode != NFSWRITE_FILESYNC) 1640 printf("ncl_doio_directwrite: Broken server " 1641 "did not reply FILE_SYNC\n"); 1642 free(iov_base, M_NFSDIRECTIO); 1643 free(uiop->uio_iov, M_NFSDIRECTIO); 1644 free(uiop, M_NFSDIRECTIO); 1645 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1646 struct nfsnode *np = VTONFS(bp->b_vp); 1647 NFSLOCKNODE(np); 1648 if (NFSHASPNFS(VFSTONFS(bp->b_vp->v_mount))) { 1649 /* 1650 * Invalidate the attribute cache, since writes to a DS 1651 * won't update the size attribute. 1652 */ 1653 np->n_attrstamp = 0; 1654 } 1655 np->n_directio_asyncwr--; 1656 if (np->n_directio_asyncwr == 0) { 1657 np->n_flag &= ~NMODIFIED; 1658 if ((np->n_flag & NFSYNCWAIT)) { 1659 np->n_flag &= ~NFSYNCWAIT; 1660 wakeup((caddr_t)&np->n_directio_asyncwr); 1661 } 1662 } 1663 NFSUNLOCKNODE(np); 1664 } 1665 bp->b_vp = NULL; 1666 uma_zfree(ncl_pbuf_zone, bp); 1667 } 1668 1669 /* 1670 * Do an I/O operation to/from a cache block. This may be called 1671 * synchronously or from an nfsiod. 1672 */ 1673 int 1674 ncl_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td, 1675 int called_from_strategy) 1676 { 1677 struct uio *uiop; 1678 struct nfsnode *np; 1679 struct nfsmount *nmp; 1680 int error = 0, iomode, must_commit = 0; 1681 struct uio uio; 1682 struct iovec io; 1683 struct proc *p = td ? td->td_proc : NULL; 1684 uint8_t iocmd; 1685 1686 np = VTONFS(vp); 1687 nmp = VFSTONFS(vp->v_mount); 1688 uiop = &uio; 1689 uiop->uio_iov = &io; 1690 uiop->uio_iovcnt = 1; 1691 uiop->uio_segflg = UIO_SYSSPACE; 1692 uiop->uio_td = td; 1693 1694 /* 1695 * clear BIO_ERROR and B_INVAL state prior to initiating the I/O. We 1696 * do this here so we do not have to do it in all the code that 1697 * calls us. 1698 */ 1699 bp->b_flags &= ~B_INVAL; 1700 bp->b_ioflags &= ~BIO_ERROR; 1701 1702 KASSERT(!(bp->b_flags & B_DONE), ("ncl_doio: bp %p already marked done", bp)); 1703 iocmd = bp->b_iocmd; 1704 if (iocmd == BIO_READ) { 1705 io.iov_len = uiop->uio_resid = bp->b_bcount; 1706 io.iov_base = bp->b_data; 1707 uiop->uio_rw = UIO_READ; 1708 1709 switch (vp->v_type) { 1710 case VREG: 1711 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1712 NFSINCRGLOBAL(nfsstatsv1.read_bios); 1713 error = ncl_readrpc(vp, uiop, cr); 1714 1715 if (!error) { 1716 if (uiop->uio_resid) { 1717 /* 1718 * If we had a short read with no error, we must have 1719 * hit a file hole. We should zero-fill the remainder. 1720 * This can also occur if the server hits the file EOF. 1721 * 1722 * Holes used to be able to occur due to pending 1723 * writes, but that is not possible any longer. 1724 */ 1725 int nread = bp->b_bcount - uiop->uio_resid; 1726 ssize_t left = uiop->uio_resid; 1727 1728 if (left > 0) 1729 bzero((char *)bp->b_data + nread, left); 1730 uiop->uio_resid = 0; 1731 } 1732 } 1733 /* ASSERT_VOP_LOCKED(vp, "ncl_doio"); */ 1734 if (p && vp->v_writecount <= -1) { 1735 NFSLOCKNODE(np); 1736 if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.na_mtime)) { 1737 NFSUNLOCKNODE(np); 1738 PROC_LOCK(p); 1739 killproc(p, "text file modification"); 1740 PROC_UNLOCK(p); 1741 } else 1742 NFSUNLOCKNODE(np); 1743 } 1744 break; 1745 case VLNK: 1746 uiop->uio_offset = (off_t)0; 1747 NFSINCRGLOBAL(nfsstatsv1.readlink_bios); 1748 error = ncl_readlinkrpc(vp, uiop, cr); 1749 break; 1750 case VDIR: 1751 NFSINCRGLOBAL(nfsstatsv1.readdir_bios); 1752 uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ; 1753 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) != 0) { 1754 error = ncl_readdirplusrpc(vp, uiop, cr, td); 1755 if (error == NFSERR_NOTSUPP) 1756 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 1757 } 1758 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 1759 error = ncl_readdirrpc(vp, uiop, cr, td); 1760 /* 1761 * end-of-directory sets B_INVAL but does not generate an 1762 * error. 1763 */ 1764 if (error == 0 && uiop->uio_resid == bp->b_bcount) 1765 bp->b_flags |= B_INVAL; 1766 break; 1767 default: 1768 printf("ncl_doio: type %x unexpected\n", vp->v_type); 1769 break; 1770 } 1771 if (error) { 1772 bp->b_ioflags |= BIO_ERROR; 1773 bp->b_error = error; 1774 } 1775 } else { 1776 /* 1777 * If we only need to commit, try to commit 1778 */ 1779 if (bp->b_flags & B_NEEDCOMMIT) { 1780 int retv; 1781 off_t off; 1782 1783 off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff; 1784 retv = ncl_commit(vp, off, bp->b_dirtyend-bp->b_dirtyoff, 1785 bp->b_wcred, td); 1786 if (NFSCL_FORCEDISM(vp->v_mount) || retv == 0) { 1787 bp->b_dirtyoff = bp->b_dirtyend = 0; 1788 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1789 bp->b_resid = 0; 1790 bufdone(bp); 1791 return (0); 1792 } 1793 if (retv == NFSERR_STALEWRITEVERF) { 1794 ncl_clearcommit(vp->v_mount); 1795 } 1796 } 1797 1798 /* 1799 * Setup for actual write 1800 */ 1801 NFSLOCKNODE(np); 1802 if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size) 1803 bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE; 1804 NFSUNLOCKNODE(np); 1805 1806 if (bp->b_dirtyend > bp->b_dirtyoff) { 1807 io.iov_len = uiop->uio_resid = bp->b_dirtyend 1808 - bp->b_dirtyoff; 1809 uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE 1810 + bp->b_dirtyoff; 1811 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 1812 uiop->uio_rw = UIO_WRITE; 1813 NFSINCRGLOBAL(nfsstatsv1.write_bios); 1814 1815 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC) 1816 iomode = NFSWRITE_UNSTABLE; 1817 else 1818 iomode = NFSWRITE_FILESYNC; 1819 1820 error = ncl_writerpc(vp, uiop, cr, &iomode, &must_commit, 1821 called_from_strategy); 1822 1823 /* 1824 * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try 1825 * to cluster the buffers needing commit. This will allow 1826 * the system to submit a single commit rpc for the whole 1827 * cluster. We can do this even if the buffer is not 100% 1828 * dirty (relative to the NFS blocksize), so we optimize the 1829 * append-to-file-case. 1830 * 1831 * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be 1832 * cleared because write clustering only works for commit 1833 * rpc's, not for the data portion of the write). 1834 */ 1835 1836 if (!error && iomode == NFSWRITE_UNSTABLE) { 1837 bp->b_flags |= B_NEEDCOMMIT; 1838 if (bp->b_dirtyoff == 0 1839 && bp->b_dirtyend == bp->b_bcount) 1840 bp->b_flags |= B_CLUSTEROK; 1841 } else { 1842 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1843 } 1844 1845 /* 1846 * For an interrupted write, the buffer is still valid 1847 * and the write hasn't been pushed to the server yet, 1848 * so we can't set BIO_ERROR and report the interruption 1849 * by setting B_EINTR. For the B_ASYNC case, B_EINTR 1850 * is not relevant, so the rpc attempt is essentially 1851 * a noop. For the case of a V3 write rpc not being 1852 * committed to stable storage, the block is still 1853 * dirty and requires either a commit rpc or another 1854 * write rpc with iomode == NFSV3WRITE_FILESYNC before 1855 * the block is reused. This is indicated by setting 1856 * the B_DELWRI and B_NEEDCOMMIT flags. 1857 * 1858 * EIO is returned by ncl_writerpc() to indicate a recoverable 1859 * write error and is handled as above, except that 1860 * B_EINTR isn't set. One cause of this is a stale stateid 1861 * error for the RPC that indicates recovery is required, 1862 * when called with called_from_strategy != 0. 1863 * 1864 * If the buffer is marked B_PAGING, it does not reside on 1865 * the vp's paging queues so we cannot call bdirty(). The 1866 * bp in this case is not an NFS cache block so we should 1867 * be safe. XXX 1868 * 1869 * The logic below breaks up errors into recoverable and 1870 * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE 1871 * and keep the buffer around for potential write retries. 1872 * For the latter (eg ESTALE), we toss the buffer away (B_INVAL) 1873 * and save the error in the nfsnode. This is less than ideal 1874 * but necessary. Keeping such buffers around could potentially 1875 * cause buffer exhaustion eventually (they can never be written 1876 * out, so will get constantly be re-dirtied). It also causes 1877 * all sorts of vfs panics. For non-recoverable write errors, 1878 * also invalidate the attrcache, so we'll be forced to go over 1879 * the wire for this object, returning an error to user on next 1880 * call (most of the time). 1881 */ 1882 if (error == EINTR || error == EIO || error == ETIMEDOUT 1883 || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 1884 bp->b_flags &= ~(B_INVAL|B_NOCACHE); 1885 if ((bp->b_flags & B_PAGING) == 0) { 1886 bdirty(bp); 1887 bp->b_flags &= ~B_DONE; 1888 } 1889 if ((error == EINTR || error == ETIMEDOUT) && 1890 (bp->b_flags & B_ASYNC) == 0) 1891 bp->b_flags |= B_EINTR; 1892 } else { 1893 if (error) { 1894 bp->b_ioflags |= BIO_ERROR; 1895 bp->b_flags |= B_INVAL; 1896 bp->b_error = np->n_error = error; 1897 NFSLOCKNODE(np); 1898 np->n_flag |= NWRITEERR; 1899 np->n_attrstamp = 0; 1900 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 1901 NFSUNLOCKNODE(np); 1902 } 1903 bp->b_dirtyoff = bp->b_dirtyend = 0; 1904 } 1905 } else { 1906 bp->b_resid = 0; 1907 bufdone(bp); 1908 return (0); 1909 } 1910 } 1911 bp->b_resid = uiop->uio_resid; 1912 if (must_commit == 1) 1913 ncl_clearcommit(vp->v_mount); 1914 bufdone(bp); 1915 return (error); 1916 } 1917 1918 /* 1919 * Used to aid in handling ftruncate() operations on the NFS client side. 1920 * Truncation creates a number of special problems for NFS. We have to 1921 * throw away VM pages and buffer cache buffers that are beyond EOF, and 1922 * we have to properly handle VM pages or (potentially dirty) buffers 1923 * that straddle the truncation point. 1924 */ 1925 1926 int 1927 ncl_meta_setsize(struct vnode *vp, struct thread *td, u_quad_t nsize) 1928 { 1929 struct nfsnode *np = VTONFS(vp); 1930 u_quad_t tsize; 1931 int biosize = vp->v_bufobj.bo_bsize; 1932 int error = 0; 1933 1934 NFSLOCKNODE(np); 1935 tsize = np->n_size; 1936 np->n_size = nsize; 1937 NFSUNLOCKNODE(np); 1938 1939 if (nsize < tsize) { 1940 struct buf *bp; 1941 daddr_t lbn; 1942 int bufsize; 1943 1944 /* 1945 * vtruncbuf() doesn't get the buffer overlapping the 1946 * truncation point. We may have a B_DELWRI and/or B_CACHE 1947 * buffer that now needs to be truncated. 1948 */ 1949 error = vtruncbuf(vp, nsize, biosize); 1950 lbn = nsize / biosize; 1951 bufsize = nsize - (lbn * biosize); 1952 bp = nfs_getcacheblk(vp, lbn, bufsize, td); 1953 if (!bp) 1954 return EINTR; 1955 if (bp->b_dirtyoff > bp->b_bcount) 1956 bp->b_dirtyoff = bp->b_bcount; 1957 if (bp->b_dirtyend > bp->b_bcount) 1958 bp->b_dirtyend = bp->b_bcount; 1959 bp->b_flags |= B_RELBUF; /* don't leave garbage around */ 1960 brelse(bp); 1961 } else { 1962 vnode_pager_setsize(vp, nsize); 1963 } 1964 return(error); 1965 } 1966