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sys/nfs/nfs_bio.c
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1 /* $NetBSD: nfs_bio.c,v 1.116.2.3 2005/12/01 16:20:34 riz Exp $ */ 2 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 __KERNEL_RCSID(0, "$NetBSD: nfs_bio.c,v 1.116.2.3 2005/12/01 16:20:34 riz Exp $"); 39 40 #include "opt_nfs.h" 41 #include "opt_ddb.h" 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/resourcevar.h> 46 #include <sys/signalvar.h> 47 #include <sys/proc.h> 48 #include <sys/buf.h> 49 #include <sys/vnode.h> 50 #include <sys/mount.h> 51 #include <sys/kernel.h> 52 #include <sys/namei.h> 53 #include <sys/dirent.h> 54 #include <sys/malloc.h> 55 56 #include <uvm/uvm_extern.h> 57 #include <uvm/uvm.h> 58 59 #include <nfs/rpcv2.h> 60 #include <nfs/nfsproto.h> 61 #include <nfs/nfs.h> 62 #include <nfs/nfsmount.h> 63 #include <nfs/nqnfs.h> 64 #include <nfs/nfsnode.h> 65 #include <nfs/nfs_var.h> 66 67 extern int nfs_numasync; 68 extern int nfs_commitsize; 69 extern struct nfsstats nfsstats; 70 71 static int nfs_doio_read __P((struct buf *, struct uio *)); 72 static int nfs_doio_write __P((struct buf *, struct uio *)); 73 static int nfs_doio_phys __P((struct buf *, struct uio *)); 74 75 /* 76 * Vnode op for read using bio 77 * Any similarity to readip() is purely coincidental 78 */ 79 int 80 nfs_bioread(vp, uio, ioflag, cred, cflag) 81 struct vnode *vp; 82 struct uio *uio; 83 int ioflag, cflag; 84 struct ucred *cred; 85 { 86 struct nfsnode *np = VTONFS(vp); 87 struct buf *bp = NULL, *rabp; 88 struct vattr vattr; 89 struct proc *p; 90 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 91 struct nfsdircache *ndp = NULL, *nndp = NULL; 92 caddr_t baddr, ep, edp; 93 int got_buf = 0, error = 0, n = 0, on = 0, en, enn; 94 int enough = 0; 95 struct dirent *dp, *pdp; 96 off_t curoff = 0; 97 98 #ifdef DIAGNOSTIC 99 if (uio->uio_rw != UIO_READ) 100 panic("nfs_read mode"); 101 #endif 102 if (uio->uio_resid == 0) 103 return (0); 104 if (vp->v_type != VDIR && uio->uio_offset < 0) 105 return (EINVAL); 106 p = uio->uio_procp; 107 #ifndef NFS_V2_ONLY 108 if ((nmp->nm_flag & NFSMNT_NFSV3) && 109 !(nmp->nm_iflag & NFSMNT_GOTFSINFO)) 110 (void)nfs_fsinfo(nmp, vp, cred, p); 111 #endif 112 if (vp->v_type != VDIR && 113 (uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 114 return (EFBIG); 115 116 /* 117 * For nfs, cache consistency can only be maintained approximately. 118 * Although RFC1094 does not specify the criteria, the following is 119 * believed to be compatible with the reference port. 120 * For nqnfs, full cache consistency is maintained within the loop. 121 * For nfs: 122 * If the file's modify time on the server has changed since the 123 * last read rpc or you have written to the file, 124 * you may have lost data cache consistency with the 125 * server, so flush all of the file's data out of the cache. 126 * Then force a getattr rpc to ensure that you have up to date 127 * attributes. 128 * NB: This implies that cache data can be read when up to 129 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 130 * attributes this could be forced by setting n_attrstamp to 0 before 131 * the VOP_GETATTR() call. 132 */ 133 134 if ((nmp->nm_flag & NFSMNT_NQNFS) == 0 && vp->v_type != VLNK) { 135 if (np->n_flag & NMODIFIED) { 136 if (vp->v_type != VREG) { 137 if (vp->v_type != VDIR) 138 panic("nfs: bioread, not dir"); 139 nfs_invaldircache(vp, 0); 140 np->n_direofoffset = 0; 141 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 142 if (error) 143 return (error); 144 } 145 NFS_INVALIDATE_ATTRCACHE(np); 146 error = VOP_GETATTR(vp, &vattr, cred, p); 147 if (error) 148 return (error); 149 np->n_mtime = vattr.va_mtime; 150 } else { 151 error = VOP_GETATTR(vp, &vattr, cred, p); 152 if (error) 153 return (error); 154 if (timespeccmp(&np->n_mtime, &vattr.va_mtime, !=)) { 155 if (vp->v_type == VDIR) { 156 nfs_invaldircache(vp, 0); 157 np->n_direofoffset = 0; 158 } 159 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 160 if (error) 161 return (error); 162 np->n_mtime = vattr.va_mtime; 163 } 164 } 165 } 166 167 do { 168 #ifndef NFS_V2_ONLY 169 /* 170 * Get a valid lease. If cached data is stale, flush it. 171 */ 172 if (nmp->nm_flag & NFSMNT_NQNFS) { 173 if (NQNFS_CKINVALID(vp, np, ND_READ)) { 174 do { 175 error = nqnfs_getlease(vp, ND_READ, cred, p); 176 } while (error == NQNFS_EXPIRED); 177 if (error) 178 return (error); 179 if (np->n_lrev != np->n_brev || 180 (np->n_flag & NQNFSNONCACHE) || 181 ((np->n_flag & NMODIFIED) && vp->v_type == VDIR)) { 182 if (vp->v_type == VDIR) { 183 nfs_invaldircache(vp, 0); 184 np->n_direofoffset = 0; 185 } 186 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 187 if (error) 188 return (error); 189 np->n_brev = np->n_lrev; 190 } 191 } else if (vp->v_type == VDIR && (np->n_flag & NMODIFIED)) { 192 nfs_invaldircache(vp, 0); 193 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 194 np->n_direofoffset = 0; 195 if (error) 196 return (error); 197 } 198 } 199 #endif 200 /* 201 * Don't cache symlinks. 202 */ 203 if (np->n_flag & NQNFSNONCACHE 204 || ((vp->v_flag & VROOT) && vp->v_type == VLNK)) { 205 switch (vp->v_type) { 206 case VREG: 207 return (nfs_readrpc(vp, uio)); 208 case VLNK: 209 return (nfs_readlinkrpc(vp, uio, cred)); 210 case VDIR: 211 break; 212 default: 213 printf(" NQNFSNONCACHE: type %x unexpected\n", 214 vp->v_type); 215 }; 216 } 217 baddr = (caddr_t)0; 218 switch (vp->v_type) { 219 case VREG: 220 nfsstats.biocache_reads++; 221 222 error = 0; 223 while (uio->uio_resid > 0) { 224 void *win; 225 vsize_t bytelen; 226 227 nfs_delayedtruncate(vp); 228 if (np->n_size <= uio->uio_offset) { 229 break; 230 } 231 bytelen = 232 MIN(np->n_size - uio->uio_offset, uio->uio_resid); 233 win = ubc_alloc(&vp->v_uobj, uio->uio_offset, 234 &bytelen, UBC_READ); 235 error = uiomove(win, bytelen, uio); 236 ubc_release(win, 0); 237 if (error) { 238 /* 239 * XXXkludge 240 * the file has been truncated on the server. 241 * there isn't much we can do. 242 */ 243 if (uio->uio_offset >= np->n_size) { 244 /* end of file */ 245 error = 0; 246 } else { 247 break; 248 } 249 } 250 } 251 break; 252 253 case VLNK: 254 nfsstats.biocache_readlinks++; 255 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, p); 256 if (!bp) 257 return (EINTR); 258 if ((bp->b_flags & B_DONE) == 0) { 259 bp->b_flags |= B_READ; 260 error = nfs_doio(bp, p); 261 if (error) { 262 brelse(bp); 263 return (error); 264 } 265 } 266 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 267 got_buf = 1; 268 on = 0; 269 break; 270 case VDIR: 271 diragain: 272 nfsstats.biocache_readdirs++; 273 ndp = nfs_searchdircache(vp, uio->uio_offset, 274 (nmp->nm_flag & NFSMNT_XLATECOOKIE), 0); 275 if (!ndp) { 276 /* 277 * We've been handed a cookie that is not 278 * in the cache. If we're not translating 279 * 32 <-> 64, it may be a value that was 280 * flushed out of the cache because it grew 281 * too big. Let the server judge if it's 282 * valid or not. In the translation case, 283 * we have no way of validating this value, 284 * so punt. 285 */ 286 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) 287 return (EINVAL); 288 ndp = nfs_enterdircache(vp, uio->uio_offset, 289 uio->uio_offset, 0, 0); 290 } 291 292 if (uio->uio_offset != 0 && 293 ndp->dc_cookie == np->n_direofoffset) { 294 nfs_putdircache(np, ndp); 295 nfsstats.direofcache_hits++; 296 return (0); 297 } 298 299 bp = nfs_getcacheblk(vp, ndp->dc_blkno, NFS_DIRBLKSIZ, p); 300 if (!bp) 301 return (EINTR); 302 if ((bp->b_flags & B_DONE) == 0) { 303 bp->b_flags |= B_READ; 304 bp->b_dcookie = ndp->dc_blkcookie; 305 error = nfs_doio(bp, p); 306 if (error) { 307 /* 308 * Yuck! The directory has been modified on the 309 * server. Punt and let the userland code 310 * deal with it. 311 */ 312 nfs_putdircache(np, ndp); 313 brelse(bp); 314 if (error == NFSERR_BAD_COOKIE) { 315 nfs_invaldircache(vp, 0); 316 nfs_vinvalbuf(vp, 0, cred, p, 1); 317 error = EINVAL; 318 } 319 return (error); 320 } 321 } 322 323 /* 324 * Just return if we hit EOF right away with this 325 * block. Always check here, because direofoffset 326 * may have been set by an nfsiod since the last 327 * check. 328 */ 329 if (np->n_direofoffset != 0 && 330 ndp->dc_blkcookie == np->n_direofoffset) { 331 nfs_putdircache(np, ndp); 332 brelse(bp); 333 return (0); 334 } 335 336 /* 337 * Find the entry we were looking for in the block. 338 */ 339 340 en = ndp->dc_entry; 341 342 pdp = dp = (struct dirent *)bp->b_data; 343 edp = bp->b_data + bp->b_bcount - bp->b_resid; 344 enn = 0; 345 while (enn < en && (caddr_t)dp < edp) { 346 pdp = dp; 347 dp = (struct dirent *)((caddr_t)dp + dp->d_reclen); 348 enn++; 349 } 350 351 /* 352 * If the entry number was bigger than the number of 353 * entries in the block, or the cookie of the previous 354 * entry doesn't match, the directory cache is 355 * stale. Flush it and try again (i.e. go to 356 * the server). 357 */ 358 if ((caddr_t)dp >= edp || (caddr_t)dp + dp->d_reclen > edp || 359 (en > 0 && NFS_GETCOOKIE(pdp) != ndp->dc_cookie)) { 360 #ifdef DEBUG 361 printf("invalid cache: %p %p %p off %lx %lx\n", 362 pdp, dp, edp, 363 (unsigned long)uio->uio_offset, 364 (unsigned long)NFS_GETCOOKIE(pdp)); 365 #endif 366 nfs_putdircache(np, ndp); 367 brelse(bp); 368 nfs_invaldircache(vp, 0); 369 nfs_vinvalbuf(vp, 0, cred, p, 0); 370 goto diragain; 371 } 372 373 on = (caddr_t)dp - bp->b_data; 374 375 /* 376 * Cache all entries that may be exported to the 377 * user, as they may be thrown back at us. The 378 * NFSBIO_CACHECOOKIES flag indicates that all 379 * entries are being 'exported', so cache them all. 380 */ 381 382 if (en == 0 && pdp == dp) { 383 dp = (struct dirent *) 384 ((caddr_t)dp + dp->d_reclen); 385 enn++; 386 } 387 388 if (uio->uio_resid < (bp->b_bcount - bp->b_resid - on)) { 389 n = uio->uio_resid; 390 enough = 1; 391 } else 392 n = bp->b_bcount - bp->b_resid - on; 393 394 ep = bp->b_data + on + n; 395 396 /* 397 * Find last complete entry to copy, caching entries 398 * (if requested) as we go. 399 */ 400 401 while ((caddr_t)dp < ep && (caddr_t)dp + dp->d_reclen <= ep) { 402 if (cflag & NFSBIO_CACHECOOKIES) { 403 nndp = nfs_enterdircache(vp, NFS_GETCOOKIE(pdp), 404 ndp->dc_blkcookie, enn, bp->b_lblkno); 405 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 406 NFS_STASHCOOKIE32(pdp, 407 nndp->dc_cookie32); 408 } 409 nfs_putdircache(np, nndp); 410 } 411 pdp = dp; 412 dp = (struct dirent *)((caddr_t)dp + dp->d_reclen); 413 enn++; 414 } 415 nfs_putdircache(np, ndp); 416 417 /* 418 * If the last requested entry was not the last in the 419 * buffer (happens if NFS_DIRFRAGSIZ < NFS_DIRBLKSIZ), 420 * cache the cookie of the last requested one, and 421 * set of the offset to it. 422 */ 423 424 if ((on + n) < bp->b_bcount - bp->b_resid) { 425 curoff = NFS_GETCOOKIE(pdp); 426 nndp = nfs_enterdircache(vp, curoff, ndp->dc_blkcookie, 427 enn, bp->b_lblkno); 428 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 429 NFS_STASHCOOKIE32(pdp, nndp->dc_cookie32); 430 curoff = nndp->dc_cookie32; 431 } 432 nfs_putdircache(np, nndp); 433 } else 434 curoff = bp->b_dcookie; 435 436 /* 437 * Always cache the entry for the next block, 438 * so that readaheads can use it. 439 */ 440 nndp = nfs_enterdircache(vp, bp->b_dcookie, bp->b_dcookie, 0,0); 441 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 442 if (curoff == bp->b_dcookie) { 443 NFS_STASHCOOKIE32(pdp, nndp->dc_cookie32); 444 curoff = nndp->dc_cookie32; 445 } 446 } 447 448 n = ((caddr_t)pdp + pdp->d_reclen) - (bp->b_data + on); 449 450 /* 451 * If not eof and read aheads are enabled, start one. 452 * (You need the current block first, so that you have the 453 * directory offset cookie of the next block.) 454 */ 455 if (nfs_numasync > 0 && nmp->nm_readahead > 0 && 456 np->n_direofoffset == 0 && !(np->n_flag & NQNFSNONCACHE)) { 457 rabp = nfs_getcacheblk(vp, nndp->dc_blkno, 458 NFS_DIRBLKSIZ, p); 459 if (rabp) { 460 if ((rabp->b_flags & (B_DONE | B_DELWRI)) == 0) { 461 rabp->b_dcookie = nndp->dc_cookie; 462 rabp->b_flags |= (B_READ | B_ASYNC); 463 if (nfs_asyncio(rabp)) { 464 rabp->b_flags |= B_INVAL; 465 brelse(rabp); 466 } 467 } else 468 brelse(rabp); 469 } 470 } 471 nfs_putdircache(np, nndp); 472 got_buf = 1; 473 break; 474 default: 475 printf(" nfsbioread: type %x unexpected\n",vp->v_type); 476 break; 477 } 478 479 if (n > 0) { 480 if (!baddr) 481 baddr = bp->b_data; 482 error = uiomove(baddr + on, (int)n, uio); 483 } 484 switch (vp->v_type) { 485 case VREG: 486 break; 487 case VLNK: 488 n = 0; 489 break; 490 case VDIR: 491 if (np->n_flag & NQNFSNONCACHE) 492 bp->b_flags |= B_INVAL; 493 uio->uio_offset = curoff; 494 if (enough) 495 n = 0; 496 break; 497 default: 498 printf(" nfsbioread: type %x unexpected\n",vp->v_type); 499 } 500 if (got_buf) 501 brelse(bp); 502 } while (error == 0 && uio->uio_resid > 0 && n > 0); 503 return (error); 504 } 505 506 /* 507 * Vnode op for write using bio 508 */ 509 int 510 nfs_write(v) 511 void *v; 512 { 513 struct vop_write_args /* { 514 struct vnode *a_vp; 515 struct uio *a_uio; 516 int a_ioflag; 517 struct ucred *a_cred; 518 } */ *ap = v; 519 struct uio *uio = ap->a_uio; 520 struct proc *p = uio->uio_procp; 521 struct vnode *vp = ap->a_vp; 522 struct nfsnode *np = VTONFS(vp); 523 struct ucred *cred = ap->a_cred; 524 int ioflag = ap->a_ioflag; 525 struct vattr vattr; 526 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 527 void *win; 528 voff_t oldoff, origoff; 529 vsize_t bytelen; 530 int error = 0; 531 int extended = 0, wrotedta = 0; 532 533 #ifdef DIAGNOSTIC 534 if (uio->uio_rw != UIO_WRITE) 535 panic("nfs_write mode"); 536 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) 537 panic("nfs_write proc"); 538 #endif 539 if (vp->v_type != VREG) 540 return (EIO); 541 if (np->n_flag & NWRITEERR) { 542 np->n_flag &= ~NWRITEERR; 543 return (np->n_error); 544 } 545 #ifndef NFS_V2_ONLY 546 if ((nmp->nm_flag & NFSMNT_NFSV3) && 547 !(nmp->nm_iflag & NFSMNT_GOTFSINFO)) 548 (void)nfs_fsinfo(nmp, vp, cred, p); 549 #endif 550 if (ioflag & (IO_APPEND | IO_SYNC)) { 551 if (np->n_flag & NMODIFIED) { 552 NFS_INVALIDATE_ATTRCACHE(np); 553 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 554 if (error) 555 return (error); 556 } 557 if (ioflag & IO_APPEND) { 558 NFS_INVALIDATE_ATTRCACHE(np); 559 error = VOP_GETATTR(vp, &vattr, cred, p); 560 if (error) 561 return (error); 562 uio->uio_offset = np->n_size; 563 } 564 } 565 if (uio->uio_offset < 0) 566 return (EINVAL); 567 if ((uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 568 return (EFBIG); 569 if (uio->uio_resid == 0) 570 return (0); 571 /* 572 * Maybe this should be above the vnode op call, but so long as 573 * file servers have no limits, i don't think it matters 574 */ 575 if (p && uio->uio_offset + uio->uio_resid > 576 p->p_rlimit[RLIMIT_FSIZE].rlim_cur) { 577 psignal(p, SIGXFSZ); 578 return (EFBIG); 579 } 580 581 if ((np->n_flag & NQNFSNONCACHE) && uio->uio_iovcnt == 1) { 582 int iomode = NFSV3WRITE_FILESYNC; 583 boolean_t stalewriteverf = FALSE; 584 585 lockmgr(&nmp->nm_writeverflock, LK_SHARED, NULL); 586 error = nfs_writerpc(vp, uio, &iomode, FALSE, &stalewriteverf); 587 lockmgr(&nmp->nm_writeverflock, LK_RELEASE, NULL); 588 if (stalewriteverf) 589 nfs_clearcommit(vp->v_mount); 590 return (error); 591 } 592 593 origoff = uio->uio_offset; 594 do { 595 boolean_t extending; /* if we are extending whole pages */ 596 u_quad_t oldsize; 597 oldoff = uio->uio_offset; 598 bytelen = uio->uio_resid; 599 600 #ifndef NFS_V2_ONLY 601 /* 602 * Check for a valid write lease. 603 */ 604 if ((nmp->nm_flag & NFSMNT_NQNFS) && 605 NQNFS_CKINVALID(vp, np, ND_WRITE)) { 606 do { 607 error = nqnfs_getlease(vp, ND_WRITE, cred, p); 608 } while (error == NQNFS_EXPIRED); 609 if (error) 610 return (error); 611 if (np->n_lrev != np->n_brev || 612 (np->n_flag & NQNFSNONCACHE)) { 613 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 614 if (error) 615 return (error); 616 np->n_brev = np->n_lrev; 617 } 618 } 619 #endif 620 nfsstats.biocache_writes++; 621 622 oldsize = np->n_size; 623 np->n_flag |= NMODIFIED; 624 if (np->n_size < uio->uio_offset + bytelen) { 625 np->n_size = uio->uio_offset + bytelen; 626 } 627 extending = ((uio->uio_offset & PAGE_MASK) == 0 && 628 (bytelen & PAGE_MASK) == 0 && 629 uio->uio_offset >= vp->v_size); 630 win = ubc_alloc(&vp->v_uobj, uio->uio_offset, &bytelen, 631 UBC_WRITE | (extending ? UBC_FAULTBUSY : 0)); 632 error = uiomove(win, bytelen, uio); 633 ubc_release(win, 0); 634 if (error) { 635 if (extending) { 636 /* 637 * backout size and free pages past eof. 638 */ 639 np->n_size = oldsize; 640 simple_lock(&vp->v_interlock); 641 (void)VOP_PUTPAGES(vp, round_page(vp->v_size), 642 0, PGO_SYNCIO | PGO_FREE); 643 } 644 break; 645 } 646 wrotedta = 1; 647 648 /* 649 * update UVM's notion of the size now that we've 650 * copied the data into the vnode's pages. 651 */ 652 653 if (vp->v_size < uio->uio_offset) { 654 uvm_vnp_setsize(vp, uio->uio_offset); 655 extended = 1; 656 } 657 658 if ((oldoff & ~(nmp->nm_wsize - 1)) != 659 (uio->uio_offset & ~(nmp->nm_wsize - 1))) { 660 simple_lock(&vp->v_interlock); 661 error = VOP_PUTPAGES(vp, 662 trunc_page(oldoff & ~(nmp->nm_wsize - 1)), 663 round_page((uio->uio_offset + nmp->nm_wsize - 1) & 664 ~(nmp->nm_wsize - 1)), PGO_CLEANIT); 665 } 666 } while (uio->uio_resid > 0); 667 if (wrotedta) 668 VN_KNOTE(vp, NOTE_WRITE | (extended ? NOTE_EXTEND : 0)); 669 if ((np->n_flag & NQNFSNONCACHE) || (ioflag & IO_SYNC)) { 670 simple_lock(&vp->v_interlock); 671 error = VOP_PUTPAGES(vp, 672 trunc_page(origoff & ~(nmp->nm_wsize - 1)), 673 round_page((uio->uio_offset + nmp->nm_wsize - 1) & 674 ~(nmp->nm_wsize - 1)), 675 PGO_CLEANIT | PGO_SYNCIO); 676 } 677 return error; 678 } 679 680 /* 681 * Get an nfs cache block. 682 * Allocate a new one if the block isn't currently in the cache 683 * and return the block marked busy. If the calling process is 684 * interrupted by a signal for an interruptible mount point, return 685 * NULL. 686 */ 687 struct buf * 688 nfs_getcacheblk(vp, bn, size, p) 689 struct vnode *vp; 690 daddr_t bn; 691 int size; 692 struct proc *p; 693 { 694 struct buf *bp; 695 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 696 697 if (nmp->nm_flag & NFSMNT_INT) { 698 bp = getblk(vp, bn, size, PCATCH, 0); 699 while (bp == NULL) { 700 if (nfs_sigintr(nmp, NULL, p)) 701 return (NULL); 702 bp = getblk(vp, bn, size, 0, 2 * hz); 703 } 704 } else 705 bp = getblk(vp, bn, size, 0, 0); 706 return (bp); 707 } 708 709 /* 710 * Flush and invalidate all dirty buffers. If another process is already 711 * doing the flush, just wait for completion. 712 */ 713 int 714 nfs_vinvalbuf(vp, flags, cred, p, intrflg) 715 struct vnode *vp; 716 int flags; 717 struct ucred *cred; 718 struct proc *p; 719 int intrflg; 720 { 721 struct nfsnode *np = VTONFS(vp); 722 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 723 int error = 0, slpflag, slptimeo; 724 725 if ((nmp->nm_flag & NFSMNT_INT) == 0) 726 intrflg = 0; 727 if (intrflg) { 728 slpflag = PCATCH; 729 slptimeo = 2 * hz; 730 } else { 731 slpflag = 0; 732 slptimeo = 0; 733 } 734 /* 735 * First wait for any other process doing a flush to complete. 736 */ 737 simple_lock(&vp->v_interlock); 738 while (np->n_flag & NFLUSHINPROG) { 739 np->n_flag |= NFLUSHWANT; 740 error = ltsleep(&np->n_flag, PRIBIO + 2, "nfsvinval", 741 slptimeo, &vp->v_interlock); 742 if (error && intrflg && nfs_sigintr(nmp, NULL, p)) { 743 simple_unlock(&vp->v_interlock); 744 return EINTR; 745 } 746 } 747 748 /* 749 * Now, flush as required. 750 */ 751 np->n_flag |= NFLUSHINPROG; 752 simple_unlock(&vp->v_interlock); 753 error = vinvalbuf(vp, flags, cred, p, slpflag, 0); 754 while (error) { 755 if (intrflg && nfs_sigintr(nmp, NULL, p)) { 756 error = EINTR; 757 break; 758 } 759 error = vinvalbuf(vp, flags, cred, p, 0, slptimeo); 760 } 761 simple_lock(&vp->v_interlock); 762 if (error == 0) 763 np->n_flag &= ~NMODIFIED; 764 np->n_flag &= ~NFLUSHINPROG; 765 if (np->n_flag & NFLUSHWANT) { 766 np->n_flag &= ~NFLUSHWANT; 767 wakeup(&np->n_flag); 768 } 769 simple_unlock(&vp->v_interlock); 770 return error; 771 } 772 773 /* 774 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 775 * This is mainly to avoid queueing async I/O requests when the nfsiods 776 * are all hung on a dead server. 777 */ 778 779 int 780 nfs_asyncio(bp) 781 struct buf *bp; 782 { 783 int i; 784 struct nfsmount *nmp; 785 int gotiod, slpflag = 0, slptimeo = 0, error; 786 787 if (nfs_numasync == 0) 788 return (EIO); 789 790 nmp = VFSTONFS(bp->b_vp->v_mount); 791 again: 792 if (nmp->nm_flag & NFSMNT_INT) 793 slpflag = PCATCH; 794 gotiod = FALSE; 795 796 /* 797 * Find a free iod to process this request. 798 */ 799 800 for (i = 0; i < NFS_MAXASYNCDAEMON; i++) { 801 struct nfs_iod *iod = &nfs_asyncdaemon[i]; 802 803 simple_lock(&iod->nid_slock); 804 if (iod->nid_want) { 805 /* 806 * Found one, so wake it up and tell it which 807 * mount to process. 808 */ 809 iod->nid_want = NULL; 810 iod->nid_mount = nmp; 811 wakeup(&iod->nid_want); 812 simple_lock(&nmp->nm_slock); 813 simple_unlock(&iod->nid_slock); 814 nmp->nm_bufqiods++; 815 gotiod = TRUE; 816 break; 817 } 818 simple_unlock(&iod->nid_slock); 819 } 820 821 /* 822 * If none are free, we may already have an iod working on this mount 823 * point. If so, it will process our request. 824 */ 825 826 if (!gotiod) { 827 simple_lock(&nmp->nm_slock); 828 if (nmp->nm_bufqiods > 0) 829 gotiod = TRUE; 830 } 831 832 LOCK_ASSERT(simple_lock_held(&nmp->nm_slock)); 833 834 /* 835 * If we have an iod which can process the request, then queue 836 * the buffer. However, even if we have an iod, do not initiate 837 * queue cleaning if curproc is the pageout daemon. if the NFS mount 838 * is via local loopback, we may put curproc (pagedaemon) to sleep 839 * waiting for the writes to complete. But the server (ourself) 840 * may block the write, waiting for its (ie., our) pagedaemon 841 * to produce clean pages to handle the write: deadlock. 842 * XXX: start non-loopback mounts straight away? If "lots free", 843 * let pagedaemon start loopback writes anyway? 844 */ 845 if (gotiod) { 846 847 /* 848 * Ensure that the queue never grows too large. 849 */ 850 if (curproc == uvm.pagedaemon_proc) { 851 /* Enque for later, to avoid free-page deadlock */ 852 (void) 0; 853 } else while (nmp->nm_bufqlen >= 2*nfs_numasync) { 854 nmp->nm_bufqwant = TRUE; 855 error = ltsleep(&nmp->nm_bufq, 856 slpflag | PRIBIO | PNORELOCK, 857 "nfsaio", slptimeo, &nmp->nm_slock); 858 if (error) { 859 if (nfs_sigintr(nmp, NULL, curproc)) 860 return (EINTR); 861 if (slpflag == PCATCH) { 862 slpflag = 0; 863 slptimeo = 2 * hz; 864 } 865 } 866 867 /* 868 * We might have lost our iod while sleeping, 869 * so check and loop if nescessary. 870 */ 871 872 if (nmp->nm_bufqiods == 0) 873 goto again; 874 875 simple_lock(&nmp->nm_slock); 876 } 877 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 878 nmp->nm_bufqlen++; 879 simple_unlock(&nmp->nm_slock); 880 return (0); 881 } 882 simple_unlock(&nmp->nm_slock); 883 884 /* 885 * All the iods are busy on other mounts, so return EIO to 886 * force the caller to process the i/o synchronously. 887 */ 888 889 return (EIO); 890 } 891 892 /* 893 * nfs_doio for read. 894 */ 895 static int 896 nfs_doio_read(bp, uiop) 897 struct buf *bp; 898 struct uio *uiop; 899 { 900 struct vnode *vp = bp->b_vp; 901 struct nfsnode *np = VTONFS(vp); 902 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 903 int error = 0; 904 905 uiop->uio_rw = UIO_READ; 906 switch (vp->v_type) { 907 case VREG: 908 nfsstats.read_bios++; 909 error = nfs_readrpc(vp, uiop); 910 if (!error && uiop->uio_resid) { 911 int diff, len; 912 913 /* 914 * If len > 0, there is a hole in the file and 915 * no writes after the hole have been pushed to 916 * the server yet. 917 * Just zero fill the rest of the valid area. 918 */ 919 920 diff = bp->b_bcount - uiop->uio_resid; 921 len = np->n_size - ((((off_t)bp->b_blkno) << DEV_BSHIFT) 922 + diff); 923 if (len > 0) { 924 len = MIN(len, uiop->uio_resid); 925 memset((char *)bp->b_data + diff, 0, len); 926 } 927 } 928 if (uiop->uio_procp && (vp->v_flag & VTEXT) && 929 (((nmp->nm_flag & NFSMNT_NQNFS) && 930 NQNFS_CKINVALID(vp, np, ND_READ) && 931 np->n_lrev != np->n_brev) || 932 (!(nmp->nm_flag & NFSMNT_NQNFS) && 933 timespeccmp(&np->n_mtime, &np->n_vattr->va_mtime, !=)))) { 934 uprintf("Process killed due to " 935 "text file modification\n"); 936 psignal(uiop->uio_procp, SIGKILL); 937 #if 0 /* XXX NJWLWP */ 938 uiop->uio_procp->p_holdcnt++; 939 #endif 940 } 941 break; 942 case VLNK: 943 KASSERT(uiop->uio_offset == (off_t)0); 944 nfsstats.readlink_bios++; 945 error = nfs_readlinkrpc(vp, uiop, curproc->p_ucred); 946 break; 947 case VDIR: 948 nfsstats.readdir_bios++; 949 uiop->uio_offset = bp->b_dcookie; 950 if (nmp->nm_flag & NFSMNT_RDIRPLUS) { 951 error = nfs_readdirplusrpc(vp, uiop, np->n_rcred); 952 if (error == NFSERR_NOTSUPP) 953 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 954 } 955 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 956 error = nfs_readdirrpc(vp, uiop, np->n_rcred); 957 if (!error) { 958 bp->b_dcookie = uiop->uio_offset; 959 } 960 break; 961 default: 962 printf("nfs_doio: type %x unexpected\n", vp->v_type); 963 break; 964 } 965 if (error) { 966 bp->b_flags |= B_ERROR; 967 bp->b_error = error; 968 } 969 return error; 970 } 971 972 /* 973 * nfs_doio for write. 974 */ 975 static int 976 nfs_doio_write(bp, uiop) 977 struct buf *bp; 978 struct uio *uiop; 979 { 980 struct vnode *vp = bp->b_vp; 981 struct nfsnode *np = VTONFS(vp); 982 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 983 int iomode; 984 boolean_t stalewriteverf = FALSE; 985 int i, npages = (bp->b_bcount + PAGE_SIZE - 1) >> PAGE_SHIFT; 986 struct vm_page *pgs[npages]; 987 boolean_t needcommit = TRUE; /* need only COMMIT RPC */ 988 boolean_t pageprotected; 989 struct uvm_object *uobj = &vp->v_uobj; 990 int error; 991 off_t off, cnt; 992 993 if ((bp->b_flags & B_ASYNC) != 0 && NFS_ISV3(vp)) { 994 iomode = NFSV3WRITE_UNSTABLE; 995 } else { 996 iomode = NFSV3WRITE_FILESYNC; 997 } 998 999 again: 1000 lockmgr(&nmp->nm_writeverflock, LK_SHARED, NULL); 1001 1002 for (i = 0; i < npages; i++) { 1003 pgs[i] = uvm_pageratop((vaddr_t)bp->b_data + (i << PAGE_SHIFT)); 1004 if (pgs[i]->uobject == uobj && 1005 pgs[i]->offset == uiop->uio_offset + (i << PAGE_SHIFT)) { 1006 KASSERT(pgs[i]->flags & PG_BUSY); 1007 /* 1008 * this page belongs to our object. 1009 */ 1010 simple_lock(&uobj->vmobjlock); 1011 /* 1012 * write out the page stably if it's about to 1013 * be released because we can't resend it 1014 * on the server crash. 1015 * 1016 * XXX assuming PG_RELEASE|PG_PAGEOUT won't be 1017 * changed until unbusy the page. 1018 */ 1019 if (pgs[i]->flags & (PG_RELEASED|PG_PAGEOUT)) 1020 iomode = NFSV3WRITE_FILESYNC; 1021 /* 1022 * if we met a page which hasn't been sent yet, 1023 * we need do WRITE RPC. 1024 */ 1025 if ((pgs[i]->flags & PG_NEEDCOMMIT) == 0) 1026 needcommit = FALSE; 1027 simple_unlock(&uobj->vmobjlock); 1028 } else { 1029 iomode = NFSV3WRITE_FILESYNC; 1030 needcommit = FALSE; 1031 } 1032 } 1033 if (!needcommit && iomode == NFSV3WRITE_UNSTABLE) { 1034 simple_lock(&uobj->vmobjlock); 1035 for (i = 0; i < npages; i++) { 1036 pgs[i]->flags |= PG_NEEDCOMMIT | PG_RDONLY; 1037 pmap_page_protect(pgs[i], VM_PROT_READ); 1038 } 1039 simple_unlock(&uobj->vmobjlock); 1040 pageprotected = TRUE; /* pages can't be modified during i/o. */ 1041 } else 1042 pageprotected = FALSE; 1043 1044 /* 1045 * Send the data to the server if necessary, 1046 * otherwise just send a commit rpc. 1047 */ 1048 1049 if (needcommit) { 1050 1051 /* 1052 * If the buffer is in the range that we already committed, 1053 * there's nothing to do. 1054 * 1055 * If it's in the range that we need to commit, push the 1056 * whole range at once, otherwise only push the buffer. 1057 * In both these cases, acquire the commit lock to avoid 1058 * other processes modifying the range. 1059 */ 1060 1061 off = uiop->uio_offset; 1062 cnt = bp->b_bcount; 1063 lockmgr(&np->n_commitlock, LK_EXCLUSIVE, NULL); 1064 if (!nfs_in_committed_range(vp, off, bp->b_bcount)) { 1065 boolean_t pushedrange; 1066 if (nfs_in_tobecommitted_range(vp, off, bp->b_bcount)) { 1067 pushedrange = TRUE; 1068 off = np->n_pushlo; 1069 cnt = np->n_pushhi - np->n_pushlo; 1070 } else { 1071 pushedrange = FALSE; 1072 } 1073 error = nfs_commit(vp, off, cnt, curproc); 1074 if (error == 0) { 1075 if (pushedrange) { 1076 nfs_merge_commit_ranges(vp); 1077 } else { 1078 nfs_add_committed_range(vp, off, cnt); 1079 } 1080 } 1081 } else { 1082 error = 0; 1083 } 1084 lockmgr(&np->n_commitlock, LK_RELEASE, NULL); 1085 lockmgr(&nmp->nm_writeverflock, LK_RELEASE, NULL); 1086 if (!error) { 1087 /* 1088 * pages are now on stable storage. 1089 */ 1090 uiop->uio_resid = 0; 1091 simple_lock(&uobj->vmobjlock); 1092 for (i = 0; i < npages; i++) { 1093 pgs[i]->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY); 1094 } 1095 simple_unlock(&uobj->vmobjlock); 1096 return 0; 1097 } else if (error == NFSERR_STALEWRITEVERF) { 1098 nfs_clearcommit(vp->v_mount); 1099 goto again; 1100 } 1101 if (error) { 1102 bp->b_flags |= B_ERROR; 1103 bp->b_error = np->n_error = error; 1104 np->n_flag |= NWRITEERR; 1105 } 1106 return error; 1107 } 1108 off = uiop->uio_offset; 1109 cnt = bp->b_bcount; 1110 uiop->uio_rw = UIO_WRITE; 1111 nfsstats.write_bios++; 1112 error = nfs_writerpc(vp, uiop, &iomode, pageprotected, &stalewriteverf); 1113 if (!error && iomode == NFSV3WRITE_UNSTABLE) { 1114 /* 1115 * we need to commit pages later. 1116 */ 1117 lockmgr(&np->n_commitlock, LK_EXCLUSIVE, NULL); 1118 nfs_add_tobecommitted_range(vp, off, cnt); 1119 /* 1120 * if there can be too many uncommitted pages, commit them now. 1121 */ 1122 if (np->n_pushhi - np->n_pushlo > nfs_commitsize) { 1123 off = np->n_pushlo; 1124 cnt = nfs_commitsize >> 1; 1125 error = nfs_commit(vp, off, cnt, curproc); 1126 if (!error) { 1127 nfs_add_committed_range(vp, off, cnt); 1128 nfs_del_tobecommitted_range(vp, off, cnt); 1129 } 1130 if (error == NFSERR_STALEWRITEVERF) { 1131 stalewriteverf = TRUE; 1132 error = 0; /* it isn't a real error */ 1133 } 1134 } else { 1135 /* 1136 * re-dirty pages so that they will be passed 1137 * to us later again. 1138 */ 1139 simple_lock(&uobj->vmobjlock); 1140 for (i = 0; i < npages; i++) { 1141 pgs[i]->flags &= ~PG_CLEAN; 1142 } 1143 simple_unlock(&uobj->vmobjlock); 1144 } 1145 lockmgr(&np->n_commitlock, LK_RELEASE, NULL); 1146 } else if (!error) { 1147 /* 1148 * pages are now on stable storage. 1149 */ 1150 lockmgr(&np->n_commitlock, LK_EXCLUSIVE, NULL); 1151 nfs_del_committed_range(vp, off, cnt); 1152 lockmgr(&np->n_commitlock, LK_RELEASE, NULL); 1153 simple_lock(&uobj->vmobjlock); 1154 for (i = 0; i < npages; i++) { 1155 pgs[i]->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY); 1156 } 1157 simple_unlock(&uobj->vmobjlock); 1158 } else { 1159 /* 1160 * we got an error. 1161 */ 1162 bp->b_flags |= B_ERROR; 1163 bp->b_error = np->n_error = error; 1164 np->n_flag |= NWRITEERR; 1165 } 1166 1167 lockmgr(&nmp->nm_writeverflock, LK_RELEASE, NULL); 1168 1169 if (stalewriteverf) { 1170 nfs_clearcommit(vp->v_mount); 1171 } 1172 return error; 1173 } 1174 1175 /* 1176 * nfs_doio for B_PHYS. 1177 */ 1178 static int 1179 nfs_doio_phys(bp, uiop) 1180 struct buf *bp; 1181 struct uio *uiop; 1182 { 1183 struct vnode *vp = bp->b_vp; 1184 int error; 1185 1186 uiop->uio_offset = ((off_t)bp->b_blkno) << DEV_BSHIFT; 1187 if (bp->b_flags & B_READ) { 1188 uiop->uio_rw = UIO_READ; 1189 nfsstats.read_physios++; 1190 error = nfs_readrpc(vp, uiop); 1191 } else { 1192 int iomode = NFSV3WRITE_DATASYNC; 1193 boolean_t stalewriteverf; 1194 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1195 1196 uiop->uio_rw = UIO_WRITE; 1197 nfsstats.write_physios++; 1198 lockmgr(&nmp->nm_writeverflock, LK_SHARED, NULL); 1199 error = nfs_writerpc(vp, uiop, &iomode, FALSE, &stalewriteverf); 1200 lockmgr(&nmp->nm_writeverflock, LK_RELEASE, NULL); 1201 if (stalewriteverf) { 1202 nfs_clearcommit(bp->b_vp->v_mount); 1203 } 1204 } 1205 if (error) { 1206 bp->b_flags |= B_ERROR; 1207 bp->b_error = error; 1208 } 1209 return error; 1210 } 1211 1212 /* 1213 * Do an I/O operation to/from a cache block. This may be called 1214 * synchronously or from an nfsiod. 1215 */ 1216 int 1217 nfs_doio(bp, p) 1218 struct buf *bp; 1219 struct proc *p; 1220 { 1221 int error; 1222 struct uio uio; 1223 struct uio *uiop = &uio; 1224 struct iovec io; 1225 UVMHIST_FUNC("nfs_doio"); UVMHIST_CALLED(ubchist); 1226 1227 uiop->uio_iov = &io; 1228 uiop->uio_iovcnt = 1; 1229 uiop->uio_segflg = UIO_SYSSPACE; 1230 uiop->uio_procp = p; 1231 uiop->uio_offset = (((off_t)bp->b_blkno) << DEV_BSHIFT); 1232 io.iov_base = bp->b_data; 1233 io.iov_len = uiop->uio_resid = bp->b_bcount; 1234 1235 /* 1236 * Historically, paging was done with physio, but no more... 1237 */ 1238 if (bp->b_flags & B_PHYS) { 1239 /* 1240 * ...though reading /dev/drum still gets us here. 1241 */ 1242 error = nfs_doio_phys(bp, uiop); 1243 } else if (bp->b_flags & B_READ) { 1244 error = nfs_doio_read(bp, uiop); 1245 } else { 1246 error = nfs_doio_write(bp, uiop); 1247 } 1248 bp->b_resid = uiop->uio_resid; 1249 biodone(bp); 1250 return (error); 1251 } 1252 1253 /* 1254 * Vnode op for VM getpages. 1255 */ 1256 1257 int 1258 nfs_getpages(v) 1259 void *v; 1260 { 1261 struct vop_getpages_args /* { 1262 struct vnode *a_vp; 1263 voff_t a_offset; 1264 struct vm_page **a_m; 1265 int *a_count; 1266 int a_centeridx; 1267 vm_prot_t a_access_type; 1268 int a_advice; 1269 int a_flags; 1270 } */ *ap = v; 1271 1272 struct vnode *vp = ap->a_vp; 1273 struct uvm_object *uobj = &vp->v_uobj; 1274 struct nfsnode *np = VTONFS(vp); 1275 const int npages = *ap->a_count; 1276 struct vm_page *pg, **pgs, *opgs[npages]; 1277 off_t origoffset, len; 1278 int i, error; 1279 boolean_t v3 = NFS_ISV3(vp); 1280 boolean_t write = (ap->a_access_type & VM_PROT_WRITE) != 0; 1281 boolean_t locked = (ap->a_flags & PGO_LOCKED) != 0; 1282 1283 /* 1284 * call the genfs code to get the pages. `pgs' may be NULL 1285 * when doing read-ahead. 1286 */ 1287 1288 pgs = ap->a_m; 1289 if (write && locked && v3) { 1290 KASSERT(pgs != NULL); 1291 #ifdef DEBUG 1292 1293 /* 1294 * If PGO_LOCKED is set, real pages shouldn't exists 1295 * in the array. 1296 */ 1297 1298 for (i = 0; i < npages; i++) 1299 KDASSERT(pgs[i] == NULL || pgs[i] == PGO_DONTCARE); 1300 #endif 1301 memcpy(opgs, pgs, npages * sizeof(struct vm_pages *)); 1302 } 1303 error = genfs_getpages(v); 1304 if (error) { 1305 return (error); 1306 } 1307 1308 /* 1309 * for read faults where the nfs node is not yet marked NMODIFIED, 1310 * set PG_RDONLY on the pages so that we come back here if someone 1311 * tries to modify later via the mapping that will be entered for 1312 * this fault. 1313 */ 1314 1315 if (!write && (np->n_flag & NMODIFIED) == 0 && pgs != NULL) { 1316 if (!locked) { 1317 simple_lock(&uobj->vmobjlock); 1318 } 1319 for (i = 0; i < npages; i++) { 1320 pg = pgs[i]; 1321 if (pg == NULL || pg == PGO_DONTCARE) { 1322 continue; 1323 } 1324 pg->flags |= PG_RDONLY; 1325 } 1326 if (!locked) { 1327 simple_unlock(&uobj->vmobjlock); 1328 } 1329 } 1330 if (!write) { 1331 return (0); 1332 } 1333 1334 /* 1335 * this is a write fault, update the commit info. 1336 */ 1337 1338 origoffset = ap->a_offset; 1339 len = npages << PAGE_SHIFT; 1340 1341 if (v3) { 1342 error = lockmgr(&np->n_commitlock, 1343 LK_EXCLUSIVE | (locked ? LK_NOWAIT : 0), NULL); 1344 if (error) { 1345 KASSERT(locked != 0); 1346 1347 /* 1348 * Since PGO_LOCKED is set, we need to unbusy 1349 * all pages fetched by genfs_getpages() above, 1350 * tell the caller that there are no pages 1351 * available and put back original pgs array. 1352 */ 1353 1354 uvm_lock_pageq(); 1355 uvm_page_unbusy(pgs, npages); 1356 uvm_unlock_pageq(); 1357 *ap->a_count = 0; 1358 memcpy(pgs, opgs, 1359 npages * sizeof(struct vm_pages *)); 1360 return (error); 1361 } 1362 nfs_del_committed_range(vp, origoffset, len); 1363 nfs_del_tobecommitted_range(vp, origoffset, len); 1364 } 1365 np->n_flag |= NMODIFIED; 1366 if (!locked) { 1367 simple_lock(&uobj->vmobjlock); 1368 } 1369 for (i = 0; i < npages; i++) { 1370 pg = pgs[i]; 1371 if (pg == NULL || pg == PGO_DONTCARE) { 1372 continue; 1373 } 1374 pg->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY); 1375 } 1376 if (!locked) { 1377 simple_unlock(&uobj->vmobjlock); 1378 } 1379 if (v3) { 1380 lockmgr(&np->n_commitlock, LK_RELEASE, NULL); 1381 } 1382 return (0); 1383 }
Cache object: ab702534b867dbb5bf26e50d2de3e06d
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