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(struct vnode *vp, struct uio *uiop, struct ucred *cred, 755 int ioflag) 756 { 757 int error; 758 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 759 struct thread *td = uiop->uio_td; 760 int size; 761 int wsize; 762 763 mtx_lock(&nmp->nm_mtx); 764 wsize = nmp->nm_wsize; 765 mtx_unlock(&nmp->nm_mtx); 766 if (ioflag & IO_SYNC) { 767 int iomode, must_commit; 768 struct uio uio; 769 struct iovec iov; 770 do_sync: 771 while (uiop->uio_resid > 0) { 772 size = MIN(uiop->uio_resid, wsize); 773 size = MIN(uiop->uio_iov->iov_len, size); 774 iov.iov_base = uiop->uio_iov->iov_base; 775 iov.iov_len = size; 776 uio.uio_iov = &iov; 777 uio.uio_iovcnt = 1; 778 uio.uio_offset = uiop->uio_offset; 779 uio.uio_resid = size; 780 uio.uio_segflg = uiop->uio_segflg; 781 uio.uio_rw = UIO_WRITE; 782 uio.uio_td = td; 783 iomode = NFSWRITE_FILESYNC; 784 /* 785 * When doing direct I/O we do not care if the 786 * server's write verifier has changed, but we 787 * do not want to update the verifier if it has 788 * changed, since that hides the change from 789 * writes being done through the buffer cache. 790 * By passing must_commit in set to two, the code 791 * in nfsrpc_writerpc() will not update the 792 * verifier on the mount point. 793 */ 794 must_commit = 2; 795 error = ncl_writerpc(vp, &uio, cred, &iomode, 796 &must_commit, 0, ioflag); 797 KASSERT((must_commit == 2), 798 ("ncl_directio_write: Updated write verifier")); 799 if (error) 800 return (error); 801 if (iomode != NFSWRITE_FILESYNC) 802 printf("nfs_directio_write: Broken server " 803 "did not reply FILE_SYNC\n"); 804 uiop->uio_offset += size; 805 uiop->uio_resid -= size; 806 if (uiop->uio_iov->iov_len <= size) { 807 uiop->uio_iovcnt--; 808 uiop->uio_iov++; 809 } else { 810 uiop->uio_iov->iov_base = 811 (char *)uiop->uio_iov->iov_base + size; 812 uiop->uio_iov->iov_len -= size; 813 } 814 } 815 } else { 816 struct uio *t_uio; 817 struct iovec *t_iov; 818 struct buf *bp; 819 820 /* 821 * Break up the write into blocksize chunks and hand these 822 * over to nfsiod's for write back. 823 * Unfortunately, this incurs a copy of the data. Since 824 * the user could modify the buffer before the write is 825 * initiated. 826 * 827 * The obvious optimization here is that one of the 2 copies 828 * in the async write path can be eliminated by copying the 829 * data here directly into mbufs and passing the mbuf chain 830 * down. But that will require a fair amount of re-working 831 * of the code and can be done if there's enough interest 832 * in NFS directio access. 833 */ 834 while (uiop->uio_resid > 0) { 835 size = MIN(uiop->uio_resid, wsize); 836 size = MIN(uiop->uio_iov->iov_len, size); 837 bp = uma_zalloc(ncl_pbuf_zone, M_WAITOK); 838 t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK); 839 t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK); 840 t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK); 841 t_iov->iov_len = size; 842 t_uio->uio_iov = t_iov; 843 t_uio->uio_iovcnt = 1; 844 t_uio->uio_offset = uiop->uio_offset; 845 t_uio->uio_resid = size; 846 t_uio->uio_segflg = UIO_SYSSPACE; 847 t_uio->uio_rw = UIO_WRITE; 848 t_uio->uio_td = td; 849 KASSERT(uiop->uio_segflg == UIO_USERSPACE || 850 uiop->uio_segflg == UIO_SYSSPACE, 851 ("nfs_directio_write: Bad uio_segflg")); 852 if (uiop->uio_segflg == UIO_USERSPACE) { 853 error = copyin(uiop->uio_iov->iov_base, 854 t_iov->iov_base, size); 855 if (error != 0) 856 goto err_free; 857 } else 858 /* 859 * UIO_SYSSPACE may never happen, but handle 860 * it just in case it does. 861 */ 862 bcopy(uiop->uio_iov->iov_base, t_iov->iov_base, 863 size); 864 bp->b_flags |= B_DIRECT; 865 bp->b_iocmd = BIO_WRITE; 866 if (cred != NOCRED) { 867 crhold(cred); 868 bp->b_wcred = cred; 869 } else 870 bp->b_wcred = NOCRED; 871 bp->b_caller1 = (void *)t_uio; 872 bp->b_vp = vp; 873 error = ncl_asyncio(nmp, bp, NOCRED, td); 874 err_free: 875 if (error) { 876 free(t_iov->iov_base, M_NFSDIRECTIO); 877 free(t_iov, M_NFSDIRECTIO); 878 free(t_uio, M_NFSDIRECTIO); 879 bp->b_vp = NULL; 880 uma_zfree(ncl_pbuf_zone, bp); 881 if (error == EINTR) 882 return (error); 883 goto do_sync; 884 } 885 uiop->uio_offset += size; 886 uiop->uio_resid -= size; 887 if (uiop->uio_iov->iov_len <= size) { 888 uiop->uio_iovcnt--; 889 uiop->uio_iov++; 890 } else { 891 uiop->uio_iov->iov_base = 892 (char *)uiop->uio_iov->iov_base + size; 893 uiop->uio_iov->iov_len -= size; 894 } 895 } 896 } 897 return (0); 898 } 899 900 /* 901 * Vnode op for write using bio 902 */ 903 int 904 ncl_write(struct vop_write_args *ap) 905 { 906 int biosize; 907 struct uio *uio = ap->a_uio; 908 struct thread *td = uio->uio_td; 909 struct vnode *vp = ap->a_vp; 910 struct nfsnode *np = VTONFS(vp); 911 struct ucred *cred = ap->a_cred; 912 int ioflag = ap->a_ioflag; 913 struct buf *bp; 914 struct vattr vattr; 915 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 916 daddr_t lbn; 917 int bcount, noncontig_write, obcount; 918 int bp_cached, n, on, error = 0, error1, save2, wouldcommit; 919 size_t orig_resid, local_resid; 920 off_t orig_size, tmp_off; 921 struct timespec ts; 922 923 KASSERT(uio->uio_rw == UIO_WRITE, ("ncl_write mode")); 924 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 925 ("ncl_write proc")); 926 if (vp->v_type != VREG) 927 return (EIO); 928 NFSLOCKNODE(np); 929 if (np->n_flag & NWRITEERR) { 930 np->n_flag &= ~NWRITEERR; 931 NFSUNLOCKNODE(np); 932 return (np->n_error); 933 } else 934 NFSUNLOCKNODE(np); 935 mtx_lock(&nmp->nm_mtx); 936 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 937 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 938 mtx_unlock(&nmp->nm_mtx); 939 (void)ncl_fsinfo(nmp, vp, cred, td); 940 mtx_lock(&nmp->nm_mtx); 941 } 942 if (nmp->nm_wsize == 0) 943 (void) newnfs_iosize(nmp); 944 mtx_unlock(&nmp->nm_mtx); 945 946 /* 947 * Synchronously flush pending buffers if we are in synchronous 948 * mode or if we are appending. 949 */ 950 if ((ioflag & IO_APPEND) || ((ioflag & IO_SYNC) && (np->n_flag & 951 NMODIFIED))) { 952 /* 953 * For the case where IO_APPEND is being done using a 954 * direct output (to the NFS server) RPC and 955 * newnfs_directio_enable is 0, all buffer cache buffers, 956 * including ones not modified, must be invalidated. 957 * This ensures that stale data is not read out of the 958 * buffer cache. The call also invalidates all mapped 959 * pages and, since the exclusive lock is held on the vnode, 960 * new pages cannot be faulted in. 961 * 962 * For the case where newnfs_directio_enable is set 963 * (which is not the default), it is not obvious that 964 * stale data should be left in the buffer cache, but 965 * the code has been this way for over a decade without 966 * complaints. Note that, unlike doing IO_APPEND via 967 * a direct write RPC when newnfs_directio_enable is not set, 968 * when newnfs_directio_enable is set, reading is done via 969 * direct to NFS server RPCs as well. 970 */ 971 np->n_attrstamp = 0; 972 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 973 error = ncl_vinvalbuf(vp, V_SAVE | ((ioflag & 974 IO_VMIO) != 0 ? V_VMIO : 0), td, 1); 975 if (error != 0) 976 return (error); 977 } 978 979 orig_resid = uio->uio_resid; 980 NFSLOCKNODE(np); 981 orig_size = np->n_size; 982 NFSUNLOCKNODE(np); 983 984 /* 985 * If IO_APPEND then load uio_offset. We restart here if we cannot 986 * get the append lock. 987 */ 988 if (ioflag & IO_APPEND) { 989 /* 990 * For NFSv4, the AppendWrite will Verify the size against 991 * the file's size on the server. If not the same, the 992 * write will then be retried, using the file size returned 993 * by the AppendWrite. However, for NFSv2 and NFSv3, the 994 * size must be acquired here via a Getattr RPC. 995 * The AppendWrite is not done for a pNFS mount. 996 */ 997 if (!NFSHASNFSV4(nmp) || NFSHASPNFS(nmp)) { 998 np->n_attrstamp = 0; 999 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 1000 error = VOP_GETATTR(vp, &vattr, cred); 1001 if (error) 1002 return (error); 1003 } 1004 NFSLOCKNODE(np); 1005 uio->uio_offset = np->n_size; 1006 NFSUNLOCKNODE(np); 1007 } 1008 1009 if (uio->uio_offset < 0) 1010 return (EINVAL); 1011 tmp_off = uio->uio_offset + uio->uio_resid; 1012 if (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset) 1013 return (EFBIG); 1014 if (uio->uio_resid == 0) 1015 return (0); 1016 1017 /* 1018 * Do IO_APPEND writing via a synchronous direct write. 1019 * This can result in a significant performance improvement. 1020 */ 1021 if ((newnfs_directio_enable && (ioflag & IO_DIRECT)) || 1022 (ioflag & IO_APPEND)) { 1023 /* 1024 * Direct writes to the server must be done NFSWRITE_FILESYNC, 1025 * because the write data is not cached and, therefore, the 1026 * write cannot be redone after a server reboot. 1027 * Set IO_SYNC to make this happen. 1028 */ 1029 ioflag |= IO_SYNC; 1030 return (nfs_directio_write(vp, uio, cred, ioflag)); 1031 } 1032 1033 /* 1034 * Maybe this should be above the vnode op call, but so long as 1035 * file servers have no limits, i don't think it matters 1036 */ 1037 error = vn_rlimit_fsize(vp, uio, td); 1038 if (error != 0) 1039 return (error); 1040 1041 save2 = curthread_pflags2_set(TDP2_SBPAGES); 1042 biosize = vp->v_bufobj.bo_bsize; 1043 /* 1044 * Find all of this file's B_NEEDCOMMIT buffers. If our writes 1045 * would exceed the local maximum per-file write commit size when 1046 * combined with those, we must decide whether to flush, 1047 * go synchronous, or return error. We don't bother checking 1048 * IO_UNIT -- we just make all writes atomic anyway, as there's 1049 * no point optimizing for something that really won't ever happen. 1050 */ 1051 wouldcommit = 0; 1052 if (!(ioflag & IO_SYNC)) { 1053 int nflag; 1054 1055 NFSLOCKNODE(np); 1056 nflag = np->n_flag; 1057 NFSUNLOCKNODE(np); 1058 if (nflag & NMODIFIED) { 1059 BO_LOCK(&vp->v_bufobj); 1060 if (vp->v_bufobj.bo_dirty.bv_cnt != 0) { 1061 TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd, 1062 b_bobufs) { 1063 if (bp->b_flags & B_NEEDCOMMIT) 1064 wouldcommit += bp->b_bcount; 1065 } 1066 } 1067 BO_UNLOCK(&vp->v_bufobj); 1068 } 1069 } 1070 1071 do { 1072 if (!(ioflag & IO_SYNC)) { 1073 wouldcommit += biosize; 1074 if (wouldcommit > nmp->nm_wcommitsize) { 1075 np->n_attrstamp = 0; 1076 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 1077 error = ncl_vinvalbuf(vp, V_SAVE | ((ioflag & 1078 IO_VMIO) != 0 ? V_VMIO : 0), td, 1); 1079 if (error != 0) 1080 goto out; 1081 wouldcommit = biosize; 1082 } 1083 } 1084 1085 NFSINCRGLOBAL(nfsstatsv1.biocache_writes); 1086 lbn = uio->uio_offset / biosize; 1087 on = uio->uio_offset - (lbn * biosize); 1088 n = MIN((unsigned)(biosize - on), uio->uio_resid); 1089 again: 1090 /* 1091 * Handle direct append and file extension cases, calculate 1092 * unaligned buffer size. 1093 */ 1094 NFSLOCKNODE(np); 1095 if ((np->n_flag & NHASBEENLOCKED) == 0 && 1096 (nmp->nm_flag & NFSMNT_NONCONTIGWR) != 0) 1097 noncontig_write = 1; 1098 else 1099 noncontig_write = 0; 1100 if ((uio->uio_offset == np->n_size || 1101 (noncontig_write != 0 && 1102 lbn == (np->n_size / biosize) && 1103 uio->uio_offset + n > np->n_size)) && n) { 1104 NFSUNLOCKNODE(np); 1105 /* 1106 * Get the buffer (in its pre-append state to maintain 1107 * B_CACHE if it was previously set). Resize the 1108 * nfsnode after we have locked the buffer to prevent 1109 * readers from reading garbage. 1110 */ 1111 obcount = np->n_size - (lbn * biosize); 1112 bp = nfs_getcacheblk(vp, lbn, obcount, td); 1113 1114 if (bp != NULL) { 1115 long save; 1116 1117 NFSLOCKNODE(np); 1118 np->n_size = uio->uio_offset + n; 1119 np->n_flag |= NMODIFIED; 1120 np->n_flag &= ~NVNSETSZSKIP; 1121 vnode_pager_setsize(vp, np->n_size); 1122 NFSUNLOCKNODE(np); 1123 1124 save = bp->b_flags & B_CACHE; 1125 bcount = on + n; 1126 allocbuf(bp, bcount); 1127 bp->b_flags |= save; 1128 if (noncontig_write != 0 && on > obcount) 1129 vfs_bio_bzero_buf(bp, obcount, on - 1130 obcount); 1131 } 1132 } else { 1133 /* 1134 * Obtain the locked cache block first, and then 1135 * adjust the file's size as appropriate. 1136 */ 1137 bcount = on + n; 1138 if ((off_t)lbn * biosize + bcount < np->n_size) { 1139 if ((off_t)(lbn + 1) * biosize < np->n_size) 1140 bcount = biosize; 1141 else 1142 bcount = np->n_size - (off_t)lbn * biosize; 1143 } 1144 NFSUNLOCKNODE(np); 1145 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1146 NFSLOCKNODE(np); 1147 if (uio->uio_offset + n > np->n_size) { 1148 np->n_size = uio->uio_offset + n; 1149 np->n_flag |= NMODIFIED; 1150 np->n_flag &= ~NVNSETSZSKIP; 1151 vnode_pager_setsize(vp, np->n_size); 1152 } 1153 NFSUNLOCKNODE(np); 1154 } 1155 1156 if (!bp) { 1157 error = newnfs_sigintr(nmp, td); 1158 if (!error) 1159 error = EINTR; 1160 break; 1161 } 1162 1163 /* 1164 * Issue a READ if B_CACHE is not set. In special-append 1165 * mode, B_CACHE is based on the buffer prior to the write 1166 * op and is typically set, avoiding the read. If a read 1167 * is required in special append mode, the server will 1168 * probably send us a short-read since we extended the file 1169 * on our end, resulting in b_resid == 0 and, thusly, 1170 * B_CACHE getting set. 1171 * 1172 * We can also avoid issuing the read if the write covers 1173 * the entire buffer. We have to make sure the buffer state 1174 * is reasonable in this case since we will not be initiating 1175 * I/O. See the comments in kern/vfs_bio.c's getblk() for 1176 * more information. 1177 * 1178 * B_CACHE may also be set due to the buffer being cached 1179 * normally. 1180 */ 1181 1182 bp_cached = 1; 1183 if (on == 0 && n == bcount) { 1184 if ((bp->b_flags & B_CACHE) == 0) 1185 bp_cached = 0; 1186 bp->b_flags |= B_CACHE; 1187 bp->b_flags &= ~B_INVAL; 1188 bp->b_ioflags &= ~BIO_ERROR; 1189 } 1190 1191 if ((bp->b_flags & B_CACHE) == 0) { 1192 bp->b_iocmd = BIO_READ; 1193 vfs_busy_pages(bp, 0); 1194 error = ncl_doio(vp, bp, cred, td, 0); 1195 if (error) { 1196 brelse(bp); 1197 break; 1198 } 1199 } 1200 if (bp->b_wcred == NOCRED) 1201 bp->b_wcred = crhold(cred); 1202 NFSLOCKNODE(np); 1203 np->n_flag |= NMODIFIED; 1204 NFSUNLOCKNODE(np); 1205 1206 /* 1207 * If dirtyend exceeds file size, chop it down. This should 1208 * not normally occur but there is an append race where it 1209 * might occur XXX, so we log it. 1210 * 1211 * If the chopping creates a reverse-indexed or degenerate 1212 * situation with dirtyoff/end, we 0 both of them. 1213 */ 1214 1215 if (bp->b_dirtyend > bcount) { 1216 printf("NFS append race @%lx:%d\n", 1217 (long)bp->b_blkno * DEV_BSIZE, 1218 bp->b_dirtyend - bcount); 1219 bp->b_dirtyend = bcount; 1220 } 1221 1222 if (bp->b_dirtyoff >= bp->b_dirtyend) 1223 bp->b_dirtyoff = bp->b_dirtyend = 0; 1224 1225 /* 1226 * If the new write will leave a contiguous dirty 1227 * area, just update the b_dirtyoff and b_dirtyend, 1228 * otherwise force a write rpc of the old dirty area. 1229 * 1230 * If there has been a file lock applied to this file 1231 * or vfs.nfs.old_noncontig_writing is set, do the following: 1232 * While it is possible to merge discontiguous writes due to 1233 * our having a B_CACHE buffer ( and thus valid read data 1234 * for the hole), we don't because it could lead to 1235 * significant cache coherency problems with multiple clients, 1236 * especially if locking is implemented later on. 1237 * 1238 * If vfs.nfs.old_noncontig_writing is not set and there has 1239 * not been file locking done on this file: 1240 * Relax coherency a bit for the sake of performance and 1241 * expand the current dirty region to contain the new 1242 * write even if it means we mark some non-dirty data as 1243 * dirty. 1244 */ 1245 1246 if (noncontig_write == 0 && bp->b_dirtyend > 0 && 1247 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 1248 if (bwrite(bp) == EINTR) { 1249 error = EINTR; 1250 break; 1251 } 1252 goto again; 1253 } 1254 1255 local_resid = uio->uio_resid; 1256 error = vn_io_fault_uiomove((char *)bp->b_data + on, n, uio); 1257 1258 if (error != 0 && !bp_cached) { 1259 /* 1260 * This block has no other content then what 1261 * possibly was written by the faulty uiomove. 1262 * Release it, forgetting the data pages, to 1263 * prevent the leak of uninitialized data to 1264 * usermode. 1265 */ 1266 bp->b_ioflags |= BIO_ERROR; 1267 brelse(bp); 1268 uio->uio_offset -= local_resid - uio->uio_resid; 1269 uio->uio_resid = local_resid; 1270 break; 1271 } 1272 1273 /* 1274 * Since this block is being modified, it must be written 1275 * again and not just committed. Since write clustering does 1276 * not work for the stage 1 data write, only the stage 2 1277 * commit rpc, we have to clear B_CLUSTEROK as well. 1278 */ 1279 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1280 1281 /* 1282 * Get the partial update on the progress made from 1283 * uiomove, if an error occurred. 1284 */ 1285 if (error != 0) 1286 n = local_resid - uio->uio_resid; 1287 1288 /* 1289 * Only update dirtyoff/dirtyend if not a degenerate 1290 * condition. 1291 */ 1292 if (n > 0) { 1293 if (bp->b_dirtyend > 0) { 1294 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 1295 bp->b_dirtyend = max((on + n), bp->b_dirtyend); 1296 } else { 1297 bp->b_dirtyoff = on; 1298 bp->b_dirtyend = on + n; 1299 } 1300 vfs_bio_set_valid(bp, on, n); 1301 } 1302 1303 /* 1304 * If IO_SYNC do bwrite(). 1305 * 1306 * IO_INVAL appears to be unused. The idea appears to be 1307 * to turn off caching in this case. Very odd. XXX 1308 */ 1309 if ((ioflag & IO_SYNC)) { 1310 if (ioflag & IO_INVAL) 1311 bp->b_flags |= B_NOCACHE; 1312 error1 = bwrite(bp); 1313 if (error1 != 0) { 1314 if (error == 0) 1315 error = error1; 1316 break; 1317 } 1318 } else if ((n + on) == biosize || (ioflag & IO_ASYNC) != 0) { 1319 bp->b_flags |= B_ASYNC; 1320 (void) ncl_writebp(bp, 0, NULL); 1321 } else { 1322 bdwrite(bp); 1323 } 1324 1325 if (error != 0) 1326 break; 1327 } while (uio->uio_resid > 0 && n > 0); 1328 1329 if (error == 0) { 1330 nanouptime(&ts); 1331 NFSLOCKNODE(np); 1332 np->n_localmodtime = ts; 1333 NFSUNLOCKNODE(np); 1334 } else { 1335 if (ioflag & IO_UNIT) { 1336 VATTR_NULL(&vattr); 1337 vattr.va_size = orig_size; 1338 /* IO_SYNC is handled implicitely */ 1339 (void)VOP_SETATTR(vp, &vattr, cred); 1340 uio->uio_offset -= orig_resid - uio->uio_resid; 1341 uio->uio_resid = orig_resid; 1342 } 1343 } 1344 1345 out: 1346 curthread_pflags2_restore(save2); 1347 return (error); 1348 } 1349 1350 /* 1351 * Get an nfs cache block. 1352 * 1353 * Allocate a new one if the block isn't currently in the cache 1354 * and return the block marked busy. If the calling process is 1355 * interrupted by a signal for an interruptible mount point, return 1356 * NULL. 1357 * 1358 * The caller must carefully deal with the possible B_INVAL state of 1359 * the buffer. ncl_doio() clears B_INVAL (and ncl_asyncio() clears it 1360 * indirectly), so synchronous reads can be issued without worrying about 1361 * the B_INVAL state. We have to be a little more careful when dealing 1362 * with writes (see comments in nfs_write()) when extending a file past 1363 * its EOF. 1364 */ 1365 static struct buf * 1366 nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td) 1367 { 1368 struct buf *bp; 1369 struct mount *mp; 1370 struct nfsmount *nmp; 1371 1372 mp = vp->v_mount; 1373 nmp = VFSTONFS(mp); 1374 1375 if (nmp->nm_flag & NFSMNT_INT) { 1376 sigset_t oldset; 1377 1378 newnfs_set_sigmask(td, &oldset); 1379 bp = getblk(vp, bn, size, PCATCH, 0, 0); 1380 newnfs_restore_sigmask(td, &oldset); 1381 while (bp == NULL) { 1382 if (newnfs_sigintr(nmp, td)) 1383 return (NULL); 1384 bp = getblk(vp, bn, size, 0, 2 * hz, 0); 1385 } 1386 } else { 1387 bp = getblk(vp, bn, size, 0, 0, 0); 1388 } 1389 1390 if (vp->v_type == VREG) 1391 bp->b_blkno = bn * (vp->v_bufobj.bo_bsize / DEV_BSIZE); 1392 return (bp); 1393 } 1394 1395 /* 1396 * Flush and invalidate all dirty buffers. If another process is already 1397 * doing the flush, just wait for completion. 1398 */ 1399 int 1400 ncl_vinvalbuf(struct vnode *vp, int flags, struct thread *td, int intrflg) 1401 { 1402 struct nfsnode *np = VTONFS(vp); 1403 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1404 int error = 0, slpflag, slptimeo; 1405 bool old_lock; 1406 struct timespec ts; 1407 1408 ASSERT_VOP_LOCKED(vp, "ncl_vinvalbuf"); 1409 1410 if ((nmp->nm_flag & NFSMNT_INT) == 0) 1411 intrflg = 0; 1412 if (NFSCL_FORCEDISM(nmp->nm_mountp)) 1413 intrflg = 1; 1414 if (intrflg) { 1415 slpflag = PCATCH; 1416 slptimeo = 2 * hz; 1417 } else { 1418 slpflag = 0; 1419 slptimeo = 0; 1420 } 1421 1422 old_lock = ncl_excl_start(vp); 1423 if (old_lock) 1424 flags |= V_ALLOWCLEAN; 1425 1426 /* 1427 * Now, flush as required. 1428 */ 1429 if ((flags & (V_SAVE | V_VMIO)) == V_SAVE && 1430 vp->v_bufobj.bo_object != NULL) { 1431 VM_OBJECT_WLOCK(vp->v_bufobj.bo_object); 1432 vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC); 1433 VM_OBJECT_WUNLOCK(vp->v_bufobj.bo_object); 1434 /* 1435 * If the page clean was interrupted, fail the invalidation. 1436 * Not doing so, we run the risk of losing dirty pages in the 1437 * vinvalbuf() call below. 1438 */ 1439 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1440 goto out; 1441 } 1442 1443 error = vinvalbuf(vp, flags, slpflag, 0); 1444 while (error) { 1445 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1446 goto out; 1447 error = vinvalbuf(vp, flags, 0, slptimeo); 1448 } 1449 if (NFSHASPNFS(nmp)) { 1450 nfscl_layoutcommit(vp, td); 1451 nanouptime(&ts); 1452 /* 1453 * Invalidate the attribute cache, since writes to a DS 1454 * won't update the size attribute. 1455 */ 1456 NFSLOCKNODE(np); 1457 np->n_attrstamp = 0; 1458 } else { 1459 nanouptime(&ts); 1460 NFSLOCKNODE(np); 1461 } 1462 if (np->n_directio_asyncwr == 0 && (np->n_flag & NMODIFIED) != 0) { 1463 np->n_localmodtime = ts; 1464 np->n_flag &= ~NMODIFIED; 1465 } 1466 NFSUNLOCKNODE(np); 1467 out: 1468 ncl_excl_finish(vp, old_lock); 1469 return error; 1470 } 1471 1472 /* 1473 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 1474 * This is mainly to avoid queueing async I/O requests when the nfsiods 1475 * are all hung on a dead server. 1476 * 1477 * Note: ncl_asyncio() does not clear (BIO_ERROR|B_INVAL) but when the bp 1478 * is eventually dequeued by the async daemon, ncl_doio() *will*. 1479 */ 1480 int 1481 ncl_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td) 1482 { 1483 int iod; 1484 int gotiod; 1485 int slpflag = 0; 1486 int slptimeo = 0; 1487 int error, error2; 1488 1489 /* 1490 * Commits are usually short and sweet so lets save some cpu and 1491 * leave the async daemons for more important rpc's (such as reads 1492 * and writes). 1493 * 1494 * Readdirplus RPCs do vget()s to acquire the vnodes for entries 1495 * in the directory in order to update attributes. This can deadlock 1496 * with another thread that is waiting for async I/O to be done by 1497 * an nfsiod thread while holding a lock on one of these vnodes. 1498 * To avoid this deadlock, don't allow the async nfsiod threads to 1499 * perform Readdirplus RPCs. 1500 */ 1501 NFSLOCKIOD(); 1502 if ((bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) && 1503 (nmp->nm_bufqiods > ncl_numasync / 2)) || 1504 (bp->b_vp->v_type == VDIR && (nmp->nm_flag & NFSMNT_RDIRPLUS))) { 1505 NFSUNLOCKIOD(); 1506 return(EIO); 1507 } 1508 again: 1509 if (nmp->nm_flag & NFSMNT_INT) 1510 slpflag = PCATCH; 1511 gotiod = FALSE; 1512 1513 /* 1514 * Find a free iod to process this request. 1515 */ 1516 for (iod = 0; iod < ncl_numasync; iod++) 1517 if (ncl_iodwant[iod] == NFSIOD_AVAILABLE) { 1518 gotiod = TRUE; 1519 break; 1520 } 1521 1522 /* 1523 * Try to create one if none are free. 1524 */ 1525 if (!gotiod) 1526 ncl_nfsiodnew(); 1527 else { 1528 /* 1529 * Found one, so wake it up and tell it which 1530 * mount to process. 1531 */ 1532 NFS_DPF(ASYNCIO, ("ncl_asyncio: waking iod %d for mount %p\n", 1533 iod, nmp)); 1534 ncl_iodwant[iod] = NFSIOD_NOT_AVAILABLE; 1535 ncl_iodmount[iod] = nmp; 1536 nmp->nm_bufqiods++; 1537 wakeup(&ncl_iodwant[iod]); 1538 } 1539 1540 /* 1541 * If none are free, we may already have an iod working on this mount 1542 * point. If so, it will process our request. 1543 */ 1544 if (!gotiod) { 1545 if (nmp->nm_bufqiods > 0) { 1546 NFS_DPF(ASYNCIO, 1547 ("ncl_asyncio: %d iods are already processing mount %p\n", 1548 nmp->nm_bufqiods, nmp)); 1549 gotiod = TRUE; 1550 } 1551 } 1552 1553 /* 1554 * If we have an iod which can process the request, then queue 1555 * the buffer. 1556 */ 1557 if (gotiod) { 1558 /* 1559 * Ensure that the queue never grows too large. We still want 1560 * to asynchronize so we block rather then return EIO. 1561 */ 1562 while (nmp->nm_bufqlen >= 2*ncl_numasync) { 1563 NFS_DPF(ASYNCIO, 1564 ("ncl_asyncio: waiting for mount %p queue to drain\n", nmp)); 1565 nmp->nm_bufqwant = TRUE; 1566 error = newnfs_msleep(td, &nmp->nm_bufq, 1567 &ncl_iod_mutex, slpflag | PRIBIO, "nfsaio", 1568 slptimeo); 1569 if (error) { 1570 error2 = newnfs_sigintr(nmp, td); 1571 if (error2) { 1572 NFSUNLOCKIOD(); 1573 return (error2); 1574 } 1575 if (slpflag == PCATCH) { 1576 slpflag = 0; 1577 slptimeo = 2 * hz; 1578 } 1579 } 1580 /* 1581 * We might have lost our iod while sleeping, 1582 * so check and loop if necessary. 1583 */ 1584 goto again; 1585 } 1586 1587 /* We might have lost our nfsiod */ 1588 if (nmp->nm_bufqiods == 0) { 1589 NFS_DPF(ASYNCIO, 1590 ("ncl_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); 1591 goto again; 1592 } 1593 1594 if (bp->b_iocmd == BIO_READ) { 1595 if (bp->b_rcred == NOCRED && cred != NOCRED) 1596 bp->b_rcred = crhold(cred); 1597 } else { 1598 if (bp->b_wcred == NOCRED && cred != NOCRED) 1599 bp->b_wcred = crhold(cred); 1600 } 1601 1602 if (bp->b_flags & B_REMFREE) 1603 bremfreef(bp); 1604 BUF_KERNPROC(bp); 1605 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 1606 nmp->nm_bufqlen++; 1607 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1608 NFSLOCKNODE(VTONFS(bp->b_vp)); 1609 VTONFS(bp->b_vp)->n_flag |= NMODIFIED; 1610 VTONFS(bp->b_vp)->n_directio_asyncwr++; 1611 NFSUNLOCKNODE(VTONFS(bp->b_vp)); 1612 } 1613 NFSUNLOCKIOD(); 1614 return (0); 1615 } 1616 1617 NFSUNLOCKIOD(); 1618 1619 /* 1620 * All the iods are busy on other mounts, so return EIO to 1621 * force the caller to process the i/o synchronously. 1622 */ 1623 NFS_DPF(ASYNCIO, ("ncl_asyncio: no iods available, i/o is synchronous\n")); 1624 return (EIO); 1625 } 1626 1627 void 1628 ncl_doio_directwrite(struct buf *bp) 1629 { 1630 int iomode, must_commit; 1631 struct uio *uiop = (struct uio *)bp->b_caller1; 1632 char *iov_base = uiop->uio_iov->iov_base; 1633 1634 iomode = NFSWRITE_FILESYNC; 1635 uiop->uio_td = NULL; /* NULL since we're in nfsiod */ 1636 /* 1637 * When doing direct I/O we do not care if the 1638 * server's write verifier has changed, but we 1639 * do not want to update the verifier if it has 1640 * changed, since that hides the change from 1641 * writes being done through the buffer cache. 1642 * By passing must_commit in set to two, the code 1643 * in nfsrpc_writerpc() will not update the 1644 * verifier on the mount point. 1645 */ 1646 must_commit = 2; 1647 ncl_writerpc(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit, 0, 0); 1648 KASSERT((must_commit == 2), ("ncl_doio_directwrite: Updated write" 1649 " verifier")); 1650 if (iomode != NFSWRITE_FILESYNC) 1651 printf("ncl_doio_directwrite: Broken server " 1652 "did not reply FILE_SYNC\n"); 1653 free(iov_base, M_NFSDIRECTIO); 1654 free(uiop->uio_iov, M_NFSDIRECTIO); 1655 free(uiop, M_NFSDIRECTIO); 1656 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1657 struct nfsnode *np = VTONFS(bp->b_vp); 1658 NFSLOCKNODE(np); 1659 if (NFSHASPNFS(VFSTONFS(bp->b_vp->v_mount))) { 1660 /* 1661 * Invalidate the attribute cache, since writes to a DS 1662 * won't update the size attribute. 1663 */ 1664 np->n_attrstamp = 0; 1665 } 1666 np->n_directio_asyncwr--; 1667 if (np->n_directio_asyncwr == 0) { 1668 np->n_flag &= ~NMODIFIED; 1669 if ((np->n_flag & NFSYNCWAIT)) { 1670 np->n_flag &= ~NFSYNCWAIT; 1671 wakeup((caddr_t)&np->n_directio_asyncwr); 1672 } 1673 } 1674 NFSUNLOCKNODE(np); 1675 } 1676 bp->b_vp = NULL; 1677 uma_zfree(ncl_pbuf_zone, bp); 1678 } 1679 1680 /* 1681 * Do an I/O operation to/from a cache block. This may be called 1682 * synchronously or from an nfsiod. 1683 */ 1684 int 1685 ncl_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td, 1686 int called_from_strategy) 1687 { 1688 struct uio *uiop; 1689 struct nfsnode *np; 1690 struct nfsmount *nmp; 1691 int error = 0, iomode, must_commit = 0; 1692 struct uio uio; 1693 struct iovec io; 1694 struct proc *p = td ? td->td_proc : NULL; 1695 uint8_t iocmd; 1696 1697 np = VTONFS(vp); 1698 nmp = VFSTONFS(vp->v_mount); 1699 uiop = &uio; 1700 uiop->uio_iov = &io; 1701 uiop->uio_iovcnt = 1; 1702 uiop->uio_segflg = UIO_SYSSPACE; 1703 uiop->uio_td = td; 1704 1705 /* 1706 * clear BIO_ERROR and B_INVAL state prior to initiating the I/O. We 1707 * do this here so we do not have to do it in all the code that 1708 * calls us. 1709 */ 1710 bp->b_flags &= ~B_INVAL; 1711 bp->b_ioflags &= ~BIO_ERROR; 1712 1713 KASSERT(!(bp->b_flags & B_DONE), ("ncl_doio: bp %p already marked done", bp)); 1714 iocmd = bp->b_iocmd; 1715 if (iocmd == BIO_READ) { 1716 io.iov_len = uiop->uio_resid = bp->b_bcount; 1717 io.iov_base = bp->b_data; 1718 uiop->uio_rw = UIO_READ; 1719 1720 switch (vp->v_type) { 1721 case VREG: 1722 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1723 NFSINCRGLOBAL(nfsstatsv1.read_bios); 1724 error = ncl_readrpc(vp, uiop, cr); 1725 1726 if (!error) { 1727 if (uiop->uio_resid) { 1728 /* 1729 * If we had a short read with no error, we must have 1730 * hit a file hole. We should zero-fill the remainder. 1731 * This can also occur if the server hits the file EOF. 1732 * 1733 * Holes used to be able to occur due to pending 1734 * writes, but that is not possible any longer. 1735 */ 1736 int nread = bp->b_bcount - uiop->uio_resid; 1737 ssize_t left = uiop->uio_resid; 1738 1739 if (left > 0) 1740 bzero((char *)bp->b_data + nread, left); 1741 uiop->uio_resid = 0; 1742 } 1743 } 1744 /* ASSERT_VOP_LOCKED(vp, "ncl_doio"); */ 1745 if (p && vp->v_writecount <= -1) { 1746 NFSLOCKNODE(np); 1747 if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.na_mtime)) { 1748 NFSUNLOCKNODE(np); 1749 PROC_LOCK(p); 1750 killproc(p, "text file modification"); 1751 PROC_UNLOCK(p); 1752 } else 1753 NFSUNLOCKNODE(np); 1754 } 1755 break; 1756 case VLNK: 1757 uiop->uio_offset = (off_t)0; 1758 NFSINCRGLOBAL(nfsstatsv1.readlink_bios); 1759 error = ncl_readlinkrpc(vp, uiop, cr); 1760 break; 1761 case VDIR: 1762 NFSINCRGLOBAL(nfsstatsv1.readdir_bios); 1763 uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ; 1764 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) != 0) { 1765 error = ncl_readdirplusrpc(vp, uiop, cr, td); 1766 if (error == NFSERR_NOTSUPP) 1767 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 1768 } 1769 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 1770 error = ncl_readdirrpc(vp, uiop, cr, td); 1771 /* 1772 * end-of-directory sets B_INVAL but does not generate an 1773 * error. 1774 */ 1775 if (error == 0 && uiop->uio_resid == bp->b_bcount) 1776 bp->b_flags |= B_INVAL; 1777 break; 1778 default: 1779 printf("ncl_doio: type %x unexpected\n", vp->v_type); 1780 break; 1781 } 1782 if (error) { 1783 bp->b_ioflags |= BIO_ERROR; 1784 bp->b_error = error; 1785 } 1786 } else { 1787 /* 1788 * If we only need to commit, try to commit 1789 */ 1790 if (bp->b_flags & B_NEEDCOMMIT) { 1791 int retv; 1792 off_t off; 1793 1794 off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff; 1795 retv = ncl_commit(vp, off, bp->b_dirtyend-bp->b_dirtyoff, 1796 bp->b_wcred, td); 1797 if (NFSCL_FORCEDISM(vp->v_mount) || retv == 0) { 1798 bp->b_dirtyoff = bp->b_dirtyend = 0; 1799 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1800 bp->b_resid = 0; 1801 bufdone(bp); 1802 return (0); 1803 } 1804 if (retv == NFSERR_STALEWRITEVERF) { 1805 ncl_clearcommit(vp->v_mount); 1806 } 1807 } 1808 1809 /* 1810 * Setup for actual write 1811 */ 1812 NFSLOCKNODE(np); 1813 if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size) 1814 bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE; 1815 NFSUNLOCKNODE(np); 1816 1817 if (bp->b_dirtyend > bp->b_dirtyoff) { 1818 io.iov_len = uiop->uio_resid = bp->b_dirtyend 1819 - bp->b_dirtyoff; 1820 uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE 1821 + bp->b_dirtyoff; 1822 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 1823 uiop->uio_rw = UIO_WRITE; 1824 NFSINCRGLOBAL(nfsstatsv1.write_bios); 1825 1826 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC) 1827 iomode = NFSWRITE_UNSTABLE; 1828 else 1829 iomode = NFSWRITE_FILESYNC; 1830 1831 error = ncl_writerpc(vp, uiop, cr, &iomode, &must_commit, 1832 called_from_strategy, 0); 1833 1834 /* 1835 * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try 1836 * to cluster the buffers needing commit. This will allow 1837 * the system to submit a single commit rpc for the whole 1838 * cluster. We can do this even if the buffer is not 100% 1839 * dirty (relative to the NFS blocksize), so we optimize the 1840 * append-to-file-case. 1841 * 1842 * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be 1843 * cleared because write clustering only works for commit 1844 * rpc's, not for the data portion of the write). 1845 */ 1846 1847 if (!error && iomode == NFSWRITE_UNSTABLE) { 1848 bp->b_flags |= B_NEEDCOMMIT; 1849 if (bp->b_dirtyoff == 0 1850 && bp->b_dirtyend == bp->b_bcount) 1851 bp->b_flags |= B_CLUSTEROK; 1852 } else { 1853 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1854 } 1855 1856 /* 1857 * For an interrupted write, the buffer is still valid 1858 * and the write hasn't been pushed to the server yet, 1859 * so we can't set BIO_ERROR and report the interruption 1860 * by setting B_EINTR. For the B_ASYNC case, B_EINTR 1861 * is not relevant, so the rpc attempt is essentially 1862 * a noop. For the case of a V3 write rpc not being 1863 * committed to stable storage, the block is still 1864 * dirty and requires either a commit rpc or another 1865 * write rpc with iomode == NFSV3WRITE_FILESYNC before 1866 * the block is reused. This is indicated by setting 1867 * the B_DELWRI and B_NEEDCOMMIT flags. 1868 * 1869 * EIO is returned by ncl_writerpc() to indicate a recoverable 1870 * write error and is handled as above, except that 1871 * B_EINTR isn't set. One cause of this is a stale stateid 1872 * error for the RPC that indicates recovery is required, 1873 * when called with called_from_strategy != 0. 1874 * 1875 * If the buffer is marked B_PAGING, it does not reside on 1876 * the vp's paging queues so we cannot call bdirty(). The 1877 * bp in this case is not an NFS cache block so we should 1878 * be safe. XXX 1879 * 1880 * The logic below breaks up errors into recoverable and 1881 * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE 1882 * and keep the buffer around for potential write retries. 1883 * For the latter (eg ESTALE), we toss the buffer away (B_INVAL) 1884 * and save the error in the nfsnode. This is less than ideal 1885 * but necessary. Keeping such buffers around could potentially 1886 * cause buffer exhaustion eventually (they can never be written 1887 * out, so will get constantly be re-dirtied). It also causes 1888 * all sorts of vfs panics. For non-recoverable write errors, 1889 * also invalidate the attrcache, so we'll be forced to go over 1890 * the wire for this object, returning an error to user on next 1891 * call (most of the time). 1892 */ 1893 if (error == EINTR || error == EIO || error == ETIMEDOUT 1894 || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 1895 bp->b_flags &= ~(B_INVAL|B_NOCACHE); 1896 if ((bp->b_flags & B_PAGING) == 0) { 1897 bdirty(bp); 1898 bp->b_flags &= ~B_DONE; 1899 } 1900 if ((error == EINTR || error == ETIMEDOUT) && 1901 (bp->b_flags & B_ASYNC) == 0) 1902 bp->b_flags |= B_EINTR; 1903 } else { 1904 if (error) { 1905 bp->b_ioflags |= BIO_ERROR; 1906 bp->b_flags |= B_INVAL; 1907 bp->b_error = np->n_error = error; 1908 NFSLOCKNODE(np); 1909 np->n_flag |= NWRITEERR; 1910 np->n_attrstamp = 0; 1911 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 1912 NFSUNLOCKNODE(np); 1913 } 1914 bp->b_dirtyoff = bp->b_dirtyend = 0; 1915 } 1916 } else { 1917 bp->b_resid = 0; 1918 bufdone(bp); 1919 return (0); 1920 } 1921 } 1922 bp->b_resid = uiop->uio_resid; 1923 if (must_commit == 1) 1924 ncl_clearcommit(vp->v_mount); 1925 bufdone(bp); 1926 return (error); 1927 } 1928 1929 /* 1930 * Used to aid in handling ftruncate() operations on the NFS client side. 1931 * Truncation creates a number of special problems for NFS. We have to 1932 * throw away VM pages and buffer cache buffers that are beyond EOF, and 1933 * we have to properly handle VM pages or (potentially dirty) buffers 1934 * that straddle the truncation point. 1935 */ 1936 1937 int 1938 ncl_meta_setsize(struct vnode *vp, struct thread *td, u_quad_t nsize) 1939 { 1940 struct nfsnode *np = VTONFS(vp); 1941 u_quad_t tsize; 1942 int biosize = vp->v_bufobj.bo_bsize; 1943 int error = 0; 1944 1945 NFSLOCKNODE(np); 1946 tsize = np->n_size; 1947 np->n_size = nsize; 1948 NFSUNLOCKNODE(np); 1949 1950 if (nsize < tsize) { 1951 struct buf *bp; 1952 daddr_t lbn; 1953 int bufsize; 1954 1955 /* 1956 * vtruncbuf() doesn't get the buffer overlapping the 1957 * truncation point. We may have a B_DELWRI and/or B_CACHE 1958 * buffer that now needs to be truncated. 1959 */ 1960 error = vtruncbuf(vp, nsize, biosize); 1961 lbn = nsize / biosize; 1962 bufsize = nsize - (lbn * biosize); 1963 bp = nfs_getcacheblk(vp, lbn, bufsize, td); 1964 if (!bp) 1965 return EINTR; 1966 if (bp->b_dirtyoff > bp->b_bcount) 1967 bp->b_dirtyoff = bp->b_bcount; 1968 if (bp->b_dirtyend > bp->b_bcount) 1969 bp->b_dirtyend = bp->b_bcount; 1970 bp->b_flags |= B_RELBUF; /* don't leave garbage around */ 1971 brelse(bp); 1972 } else { 1973 vnode_pager_setsize(vp, nsize); 1974 } 1975 return(error); 1976 } 1977