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