1 /* $OpenBSD: nfs_bio.c,v 1.81 2016/02/13 15:45:05 stefan Exp $ */ 2 /* $NetBSD: nfs_bio.c,v 1.25.4.2 1996/07/08 20:47:04 jtc Exp $ */ 3 4 /* 5 * Copyright (c) 1989, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Rick Macklem at The University of Guelph. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/resourcevar.h> 41 #include <sys/signalvar.h> 42 #include <sys/proc.h> 43 #include <sys/buf.h> 44 #include <sys/vnode.h> 45 #include <sys/mount.h> 46 #include <sys/kernel.h> 47 #include <sys/namei.h> 48 #include <sys/queue.h> 49 #include <sys/time.h> 50 51 #include <nfs/nfsproto.h> 52 #include <nfs/nfs.h> 53 #include <nfs/nfsmount.h> 54 #include <nfs/nfsnode.h> 55 #include <nfs/nfs_var.h> 56 57 extern int nfs_numasync; 58 extern struct nfsstats nfsstats; 59 struct nfs_bufqhead nfs_bufq; 60 uint32_t nfs_bufqmax, nfs_bufqlen; 61 62 /* 63 * Vnode op for read using bio 64 * Any similarity to readip() is purely coincidental 65 */ 66 int 67 nfs_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred) 68 { 69 struct nfsnode *np = VTONFS(vp); 70 int biosize, diff; 71 struct buf *bp = NULL, *rabp; 72 struct vattr vattr; 73 struct proc *p; 74 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 75 daddr_t lbn, bn, rabn; 76 caddr_t baddr; 77 int got_buf = 0, nra, error = 0, n = 0, on = 0, not_readin; 78 off_t offdiff; 79 80 #ifdef DIAGNOSTIC 81 if (uio->uio_rw != UIO_READ) 82 panic("nfs_read mode"); 83 #endif 84 if (uio->uio_resid == 0) 85 return (0); 86 if (uio->uio_offset < 0) 87 return (EINVAL); 88 p = uio->uio_procp; 89 if ((nmp->nm_flag & (NFSMNT_NFSV3 | NFSMNT_GOTFSINFO)) == NFSMNT_NFSV3) 90 (void)nfs_fsinfo(nmp, vp, cred, p); 91 biosize = nmp->nm_rsize; 92 /* 93 * For nfs, cache consistency can only be maintained approximately. 94 * Although RFC1094 does not specify the criteria, the following is 95 * believed to be compatible with the reference port. 96 * For nfs: 97 * If the file's modify time on the server has changed since the 98 * last read rpc or you have written to the file, 99 * you may have lost data cache consistency with the 100 * server, so flush all of the file's data out of the cache. 101 * Then force a getattr rpc to ensure that you have up to date 102 * attributes. 103 */ 104 if (np->n_flag & NMODIFIED) { 105 NFS_INVALIDATE_ATTRCACHE(np); 106 error = VOP_GETATTR(vp, &vattr, cred, p); 107 if (error) 108 return (error); 109 np->n_mtime = vattr.va_mtime; 110 } else { 111 error = VOP_GETATTR(vp, &vattr, cred, p); 112 if (error) 113 return (error); 114 if (timespeccmp(&np->n_mtime, &vattr.va_mtime, !=)) { 115 error = nfs_vinvalbuf(vp, V_SAVE, cred, p); 116 if (error) 117 return (error); 118 np->n_mtime = vattr.va_mtime; 119 } 120 } 121 122 /* 123 * update the cache read creds for this vnode 124 */ 125 if (np->n_rcred) 126 crfree(np->n_rcred); 127 np->n_rcred = cred; 128 crhold(cred); 129 130 do { 131 if ((vp->v_flag & VROOT) && vp->v_type == VLNK) { 132 return (nfs_readlinkrpc(vp, uio, cred)); 133 } 134 baddr = NULL; 135 switch (vp->v_type) { 136 case VREG: 137 nfsstats.biocache_reads++; 138 lbn = uio->uio_offset / biosize; 139 on = uio->uio_offset & (biosize - 1); 140 bn = lbn * (biosize / DEV_BSIZE); 141 not_readin = 1; 142 143 /* 144 * Start the read ahead(s), as required. 145 */ 146 if (nfs_numasync > 0 && nmp->nm_readahead > 0) { 147 for (nra = 0; nra < nmp->nm_readahead && 148 (lbn + 1 + nra) * biosize < np->n_size; nra++) { 149 rabn = (lbn + 1 + nra) * (biosize / DEV_BSIZE); 150 if (!incore(vp, rabn)) { 151 rabp = nfs_getcacheblk(vp, rabn, biosize, p); 152 if (!rabp) 153 return (EINTR); 154 if ((rabp->b_flags & (B_DELWRI | B_DONE)) == 0) { 155 rabp->b_flags |= (B_READ | B_ASYNC); 156 if (nfs_asyncio(rabp, 1)) { 157 rabp->b_flags |= B_INVAL; 158 brelse(rabp); 159 } 160 } else 161 brelse(rabp); 162 } 163 } 164 } 165 166 again: 167 bp = nfs_getcacheblk(vp, bn, biosize, p); 168 if (!bp) 169 return (EINTR); 170 got_buf = 1; 171 if ((bp->b_flags & (B_DONE | B_DELWRI)) == 0) { 172 bp->b_flags |= B_READ; 173 not_readin = 0; 174 error = nfs_doio(bp, p); 175 if (error) { 176 brelse(bp); 177 return (error); 178 } 179 } 180 n = ulmin(biosize - on, uio->uio_resid); 181 offdiff = np->n_size - uio->uio_offset; 182 if (offdiff < (off_t)n) 183 n = (int)offdiff; 184 if (not_readin && n > 0) { 185 if (on < bp->b_validoff || (on + n) > bp->b_validend) { 186 bp->b_flags |= B_INVAFTERWRITE; 187 if (bp->b_dirtyend > 0) { 188 if ((bp->b_flags & B_DELWRI) == 0) 189 panic("nfsbioread"); 190 if (VOP_BWRITE(bp) == EINTR) 191 return (EINTR); 192 } else 193 brelse(bp); 194 goto again; 195 } 196 } 197 diff = (on >= bp->b_validend) ? 0 : (bp->b_validend - on); 198 if (diff < n) 199 n = diff; 200 break; 201 case VLNK: 202 nfsstats.biocache_readlinks++; 203 bp = nfs_getcacheblk(vp, 0, NFS_MAXPATHLEN, p); 204 if (!bp) 205 return (EINTR); 206 if ((bp->b_flags & B_DONE) == 0) { 207 bp->b_flags |= B_READ; 208 error = nfs_doio(bp, p); 209 if (error) { 210 brelse(bp); 211 return (error); 212 } 213 } 214 n = ulmin(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 215 got_buf = 1; 216 on = 0; 217 break; 218 default: 219 panic("nfsbioread: type %x unexpected", vp->v_type); 220 break; 221 } 222 223 if (n > 0) { 224 if (!baddr) 225 baddr = bp->b_data; 226 error = uiomove(baddr + on, n, uio); 227 } 228 229 if (vp->v_type == VLNK) 230 n = 0; 231 232 if (got_buf) 233 brelse(bp); 234 } while (error == 0 && uio->uio_resid > 0 && n > 0); 235 return (error); 236 } 237 238 /* 239 * Vnode op for write using bio 240 */ 241 int 242 nfs_write(void *v) 243 { 244 struct vop_write_args *ap = v; 245 int biosize; 246 struct uio *uio = ap->a_uio; 247 struct proc *p = uio->uio_procp; 248 struct vnode *vp = ap->a_vp; 249 struct nfsnode *np = VTONFS(vp); 250 struct ucred *cred = ap->a_cred; 251 int ioflag = ap->a_ioflag; 252 struct buf *bp; 253 struct vattr vattr; 254 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 255 daddr_t lbn, bn; 256 int n, on, error = 0, extended = 0, wrotedta = 0, truncated = 0; 257 ssize_t overrun; 258 259 #ifdef DIAGNOSTIC 260 if (uio->uio_rw != UIO_WRITE) 261 panic("nfs_write mode"); 262 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) 263 panic("nfs_write proc"); 264 #endif 265 if (vp->v_type != VREG) 266 return (EIO); 267 if (np->n_flag & NWRITEERR) { 268 np->n_flag &= ~NWRITEERR; 269 return (np->n_error); 270 } 271 if ((nmp->nm_flag & (NFSMNT_NFSV3 | NFSMNT_GOTFSINFO)) == NFSMNT_NFSV3) 272 (void)nfs_fsinfo(nmp, vp, cred, p); 273 if (ioflag & (IO_APPEND | IO_SYNC)) { 274 if (np->n_flag & NMODIFIED) { 275 NFS_INVALIDATE_ATTRCACHE(np); 276 error = nfs_vinvalbuf(vp, V_SAVE, cred, p); 277 if (error) 278 return (error); 279 } 280 if (ioflag & IO_APPEND) { 281 NFS_INVALIDATE_ATTRCACHE(np); 282 error = VOP_GETATTR(vp, &vattr, cred, p); 283 if (error) 284 return (error); 285 uio->uio_offset = np->n_size; 286 } 287 } 288 if (uio->uio_offset < 0) 289 return (EINVAL); 290 if (uio->uio_resid == 0) 291 return (0); 292 293 /* do the filesize rlimit check */ 294 if ((error = vn_fsizechk(vp, uio, ioflag, &overrun))) 295 return (error); 296 297 /* 298 * update the cache write creds for this node. 299 */ 300 if (np->n_wcred) 301 crfree(np->n_wcred); 302 np->n_wcred = cred; 303 crhold(cred); 304 305 /* 306 * I use nm_rsize, not nm_wsize so that all buffer cache blocks 307 * will be the same size within a filesystem. nfs_writerpc will 308 * still use nm_wsize when sizing the rpc's. 309 */ 310 biosize = nmp->nm_rsize; 311 do { 312 313 /* 314 * XXX make sure we aren't cached in the VM page cache 315 */ 316 uvm_vnp_uncache(vp); 317 318 nfsstats.biocache_writes++; 319 lbn = uio->uio_offset / biosize; 320 on = uio->uio_offset & (biosize-1); 321 n = ulmin(biosize - on, uio->uio_resid); 322 bn = lbn * (biosize / DEV_BSIZE); 323 again: 324 bp = nfs_getcacheblk(vp, bn, biosize, p); 325 if (!bp) { 326 error = EINTR; 327 goto out; 328 } 329 np->n_flag |= NMODIFIED; 330 if (uio->uio_offset + n > np->n_size) { 331 np->n_size = uio->uio_offset + n; 332 uvm_vnp_setsize(vp, (u_long)np->n_size); 333 extended = 1; 334 } else if (uio->uio_offset + n < np->n_size) 335 truncated = 1; 336 337 /* 338 * If the new write will leave a contiguous dirty 339 * area, just update the b_dirtyoff and b_dirtyend, 340 * otherwise force a write rpc of the old dirty area. 341 */ 342 if (bp->b_dirtyend > 0 && 343 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 344 bp->b_proc = p; 345 if (VOP_BWRITE(bp) == EINTR) { 346 error = EINTR; 347 goto out; 348 } 349 goto again; 350 } 351 352 error = uiomove((char *)bp->b_data + on, n, uio); 353 if (error) { 354 bp->b_flags |= B_ERROR; 355 brelse(bp); 356 goto out; 357 } 358 if (bp->b_dirtyend > 0) { 359 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 360 bp->b_dirtyend = max((on + n), bp->b_dirtyend); 361 } else { 362 bp->b_dirtyoff = on; 363 bp->b_dirtyend = on + n; 364 } 365 if (bp->b_validend == 0 || bp->b_validend < bp->b_dirtyoff || 366 bp->b_validoff > bp->b_dirtyend) { 367 bp->b_validoff = bp->b_dirtyoff; 368 bp->b_validend = bp->b_dirtyend; 369 } else { 370 bp->b_validoff = min(bp->b_validoff, bp->b_dirtyoff); 371 bp->b_validend = max(bp->b_validend, bp->b_dirtyend); 372 } 373 374 wrotedta = 1; 375 376 /* 377 * Since this block is being modified, it must be written 378 * again and not just committed. 379 */ 380 381 if (NFS_ISV3(vp)) { 382 rw_enter_write(&np->n_commitlock); 383 if (bp->b_flags & B_NEEDCOMMIT) { 384 bp->b_flags &= ~B_NEEDCOMMIT; 385 nfs_del_tobecommitted_range(vp, bp); 386 } 387 nfs_del_committed_range(vp, bp); 388 rw_exit_write(&np->n_commitlock); 389 } else 390 bp->b_flags &= ~B_NEEDCOMMIT; 391 392 if (ioflag & IO_SYNC) { 393 bp->b_proc = p; 394 error = VOP_BWRITE(bp); 395 if (error) 396 goto out; 397 } else if ((n + on) == biosize) { 398 bp->b_proc = NULL; 399 bp->b_flags |= B_ASYNC; 400 (void)nfs_writebp(bp, 0); 401 } else { 402 bdwrite(bp); 403 } 404 } while (uio->uio_resid > 0 && n > 0); 405 406 /*out: XXX belongs here??? */ 407 if (wrotedta) 408 VN_KNOTE(vp, NOTE_WRITE | (extended ? NOTE_EXTEND : 0) | 409 (truncated ? NOTE_TRUNCATE : 0)); 410 411 out: 412 /* correct the result for writes clamped by vn_fsizechk() */ 413 uio->uio_resid += overrun; 414 415 return (error); 416 } 417 418 /* 419 * Get an nfs cache block. 420 * Allocate a new one if the block isn't currently in the cache 421 * and return the block marked busy. If the calling process is 422 * interrupted by a signal for an interruptible mount point, return 423 * NULL. 424 */ 425 struct buf * 426 nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct proc *p) 427 { 428 struct buf *bp; 429 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 430 431 if (nmp->nm_flag & NFSMNT_INT) { 432 bp = getblk(vp, bn, size, PCATCH, 0); 433 while (bp == NULL) { 434 if (nfs_sigintr(nmp, NULL, p)) 435 return (NULL); 436 bp = getblk(vp, bn, size, 0, 2 * hz); 437 } 438 } else 439 bp = getblk(vp, bn, size, 0, 0); 440 return (bp); 441 } 442 443 /* 444 * Flush and invalidate all dirty buffers. If another process is already 445 * doing the flush, just wait for completion. 446 */ 447 int 448 nfs_vinvalbuf(struct vnode *vp, int flags, struct ucred *cred, struct proc *p) 449 { 450 struct nfsmount *nmp= VFSTONFS(vp->v_mount); 451 struct nfsnode *np = VTONFS(vp); 452 int error, sintr, stimeo; 453 454 error = sintr = stimeo = 0; 455 456 if (ISSET(nmp->nm_flag, NFSMNT_INT)) { 457 sintr = PCATCH; 458 stimeo = 2 * hz; 459 } 460 461 /* First wait for any other process doing a flush to complete. */ 462 while (np->n_flag & NFLUSHINPROG) { 463 np->n_flag |= NFLUSHWANT; 464 error = tsleep(&np->n_flag, PRIBIO|sintr, "nfsvinval", stimeo); 465 if (error && sintr && nfs_sigintr(nmp, NULL, p)) 466 return (EINTR); 467 } 468 469 /* Now, flush as required. */ 470 np->n_flag |= NFLUSHINPROG; 471 error = vinvalbuf(vp, flags, cred, p, sintr, 0); 472 while (error) { 473 if (sintr && nfs_sigintr(nmp, NULL, p)) { 474 np->n_flag &= ~NFLUSHINPROG; 475 if (np->n_flag & NFLUSHWANT) { 476 np->n_flag &= ~NFLUSHWANT; 477 wakeup(&np->n_flag); 478 } 479 return (EINTR); 480 } 481 error = vinvalbuf(vp, flags, cred, p, 0, stimeo); 482 } 483 np->n_flag &= ~(NMODIFIED | NFLUSHINPROG); 484 if (np->n_flag & NFLUSHWANT) { 485 np->n_flag &= ~NFLUSHWANT; 486 wakeup(&np->n_flag); 487 } 488 return (0); 489 } 490 491 /* 492 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 493 * This is mainly to avoid queueing async I/O requests when the nfsiods 494 * are all hung on a dead server. 495 */ 496 int 497 nfs_asyncio(struct buf *bp, int readahead) 498 { 499 if (nfs_numasync == 0) 500 goto out; 501 502 while (nfs_bufqlen > nfs_bufqmax) 503 if (readahead) 504 goto out; 505 else 506 tsleep(&nfs_bufqlen, PRIBIO, "nfs_bufq", 0); 507 508 if ((bp->b_flags & B_READ) == 0) { 509 bp->b_flags |= B_WRITEINPROG; 510 } 511 512 TAILQ_INSERT_TAIL(&nfs_bufq, bp, b_freelist); 513 nfs_bufqlen++; 514 515 wakeup_one(&nfs_bufq); 516 return (0); 517 518 out: 519 nfsstats.forcedsync++; 520 return (EIO); 521 } 522 523 /* 524 * Do an I/O operation to/from a cache block. This may be called 525 * synchronously or from an nfsiod. 526 */ 527 int 528 nfs_doio(struct buf *bp, struct proc *p) 529 { 530 struct uio *uiop; 531 struct vnode *vp; 532 struct nfsnode *np; 533 struct nfsmount *nmp; 534 int s, error = 0, diff, len, iomode, must_commit = 0; 535 struct uio uio; 536 struct iovec io; 537 538 vp = bp->b_vp; 539 np = VTONFS(vp); 540 nmp = VFSTONFS(vp->v_mount); 541 uiop = &uio; 542 uiop->uio_iov = &io; 543 uiop->uio_iovcnt = 1; 544 uiop->uio_segflg = UIO_SYSSPACE; 545 uiop->uio_procp = p; 546 547 /* 548 * Historically, paging was done with physio, but no more. 549 */ 550 if (bp->b_flags & B_PHYS) { 551 io.iov_len = uiop->uio_resid = bp->b_bcount; 552 /* mapping was done by vmapbuf() */ 553 io.iov_base = bp->b_data; 554 uiop->uio_offset = ((off_t)bp->b_blkno) << DEV_BSHIFT; 555 if (bp->b_flags & B_READ) { 556 uiop->uio_rw = UIO_READ; 557 nfsstats.read_physios++; 558 error = nfs_readrpc(vp, uiop); 559 } else { 560 iomode = NFSV3WRITE_DATASYNC; 561 uiop->uio_rw = UIO_WRITE; 562 nfsstats.write_physios++; 563 error = nfs_writerpc(vp, uiop, &iomode, &must_commit); 564 } 565 if (error) { 566 bp->b_flags |= B_ERROR; 567 bp->b_error = error; 568 } 569 } else if (bp->b_flags & B_READ) { 570 io.iov_len = uiop->uio_resid = bp->b_bcount; 571 io.iov_base = bp->b_data; 572 uiop->uio_rw = UIO_READ; 573 switch (vp->v_type) { 574 case VREG: 575 uiop->uio_offset = ((off_t)bp->b_blkno) << DEV_BSHIFT; 576 nfsstats.read_bios++; 577 bcstats.pendingreads++; 578 bcstats.numreads++; 579 error = nfs_readrpc(vp, uiop); 580 if (!error) { 581 bp->b_validoff = 0; 582 if (uiop->uio_resid) { 583 /* 584 * If len > 0, there is a hole in the file and 585 * no writes after the hole have been pushed to 586 * the server yet. 587 * Just zero fill the rest of the valid area. 588 */ 589 diff = bp->b_bcount - uiop->uio_resid; 590 len = np->n_size - ((((off_t)bp->b_blkno) << DEV_BSHIFT) 591 + diff); 592 if (len > 0) { 593 len = ulmin(len, uiop->uio_resid); 594 memset((char *)bp->b_data + diff, 0, len); 595 bp->b_validend = diff + len; 596 } else 597 bp->b_validend = diff; 598 } else 599 bp->b_validend = bp->b_bcount; 600 } 601 if (p && (vp->v_flag & VTEXT) && 602 (timespeccmp(&np->n_mtime, &np->n_vattr.va_mtime, !=))) { 603 uprintf("Process killed due to text file modification\n"); 604 psignal(p, SIGKILL); 605 } 606 break; 607 case VLNK: 608 uiop->uio_offset = (off_t)0; 609 nfsstats.readlink_bios++; 610 bcstats.pendingreads++; 611 bcstats.numreads++; 612 error = nfs_readlinkrpc(vp, uiop, curproc->p_ucred); 613 break; 614 default: 615 panic("nfs_doio: type %x unexpected", vp->v_type); 616 break; 617 }; 618 if (error) { 619 bp->b_flags |= B_ERROR; 620 bp->b_error = error; 621 } 622 } else { 623 io.iov_len = uiop->uio_resid = bp->b_dirtyend 624 - bp->b_dirtyoff; 625 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE 626 + bp->b_dirtyoff; 627 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 628 uiop->uio_rw = UIO_WRITE; 629 nfsstats.write_bios++; 630 bcstats.pendingwrites++; 631 bcstats.numwrites++; 632 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE)) == B_ASYNC) 633 iomode = NFSV3WRITE_UNSTABLE; 634 else 635 iomode = NFSV3WRITE_FILESYNC; 636 bp->b_flags |= B_WRITEINPROG; 637 error = nfs_writerpc(vp, uiop, &iomode, &must_commit); 638 639 rw_enter_write(&np->n_commitlock); 640 if (!error && iomode == NFSV3WRITE_UNSTABLE) { 641 bp->b_flags |= B_NEEDCOMMIT; 642 nfs_add_tobecommitted_range(vp, bp); 643 } else { 644 bp->b_flags &= ~B_NEEDCOMMIT; 645 nfs_del_committed_range(vp, bp); 646 } 647 rw_exit_write(&np->n_commitlock); 648 649 bp->b_flags &= ~B_WRITEINPROG; 650 651 /* 652 * For an interrupted write, the buffer is still valid and the 653 * write hasn't been pushed to the server yet, so we can't set 654 * B_ERROR and report the interruption by setting B_EINTR. For 655 * the B_ASYNC case, B_EINTR is not relevant, so the rpc attempt 656 * is essentially a noop. 657 * For the case of a V3 write rpc not being committed to stable 658 * storage, the block is still dirty and requires either a commit 659 * rpc or another write rpc with iomode == NFSV3WRITE_FILESYNC 660 * before the block is reused. This is indicated by setting the 661 * B_DELWRI and B_NEEDCOMMIT flags. 662 */ 663 if (error == EINTR || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 664 s = splbio(); 665 buf_dirty(bp); 666 splx(s); 667 668 if (!(bp->b_flags & B_ASYNC) && error) 669 bp->b_flags |= B_EINTR; 670 } else { 671 if (error) { 672 bp->b_flags |= B_ERROR; 673 bp->b_error = np->n_error = error; 674 np->n_flag |= NWRITEERR; 675 } 676 bp->b_dirtyoff = bp->b_dirtyend = 0; 677 } 678 } 679 bp->b_resid = uiop->uio_resid; 680 if (must_commit) 681 nfs_clearcommit(vp->v_mount); 682 s = splbio(); 683 biodone(bp); 684 splx(s); 685 return (error); 686 } 687