1 /* $NetBSD: nfs_bio.c,v 1.141 2006/01/14 08:57:40 yamt 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 1.141 2006/01/14 08:57:40 yamt 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 lwp *l = uio->uio_lwp; 89 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 90 struct nfsdircache *ndp = NULL, *nndp = NULL; 91 caddr_t baddr; 92 int got_buf = 0, error = 0, n = 0, on = 0, en, enn; 93 int enough = 0; 94 struct dirent *dp, *pdp, *edp, *ep; 95 off_t curoff = 0; 96 int advice; 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 #ifndef NFS_V2_ONLY 107 if ((nmp->nm_flag & NFSMNT_NFSV3) && 108 !(nmp->nm_iflag & NFSMNT_GOTFSINFO)) 109 (void)nfs_fsinfo(nmp, vp, cred, l); 110 #endif 111 if (vp->v_type != VDIR && 112 (uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 113 return (EFBIG); 114 115 /* 116 * For nfs, cache consistency can only be maintained approximately. 117 * Although RFC1094 does not specify the criteria, the following is 118 * believed to be compatible with the reference port. 119 * For nqnfs, full cache consistency is maintained within the loop. 120 * For nfs: 121 * If the file's modify time on the server has changed since the 122 * last read rpc or you have written to the file, 123 * you may have lost data cache consistency with the 124 * server, so flush all of the file's data out of the cache. 125 * Then force a getattr rpc to ensure that you have up to date 126 * attributes. 127 * NB: This implies that cache data can be read when up to 128 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 129 * attributes this could be forced by setting n_attrstamp to 0 before 130 * the VOP_GETATTR() call. 131 */ 132 133 if ((nmp->nm_flag & NFSMNT_NQNFS) == 0 && vp->v_type != VLNK) { 134 error = nfs_flushstalebuf(vp, cred, l, 135 NFS_FLUSHSTALEBUF_MYWRITE); 136 if (error) 137 return error; 138 } 139 140 do { 141 #ifndef NFS_V2_ONLY 142 /* 143 * Get a valid lease. If cached data is stale, flush it. 144 */ 145 if (nmp->nm_flag & NFSMNT_NQNFS) { 146 if (NQNFS_CKINVALID(vp, np, ND_READ)) { 147 do { 148 error = nqnfs_getlease(vp, ND_READ, cred, l); 149 } while (error == NQNFS_EXPIRED); 150 if (error) 151 return (error); 152 if (np->n_lrev != np->n_brev || 153 (np->n_flag & NQNFSNONCACHE) || 154 ((np->n_flag & NMODIFIED) && vp->v_type == VDIR)) { 155 if (vp->v_type == VDIR) { 156 nfs_invaldircache(vp, 0); 157 } 158 error = nfs_vinvalbuf(vp, V_SAVE, cred, l, 1); 159 if (error) 160 return (error); 161 np->n_brev = np->n_lrev; 162 } 163 } else if (vp->v_type == VDIR && (np->n_flag & NMODIFIED)) { 164 nfs_invaldircache(vp, 0); 165 error = nfs_vinvalbuf(vp, V_SAVE, cred, l, 1); 166 if (error) 167 return (error); 168 } 169 } 170 #endif 171 /* 172 * Don't cache symlinks. 173 */ 174 if (np->n_flag & NQNFSNONCACHE 175 || ((vp->v_flag & VROOT) && vp->v_type == VLNK)) { 176 switch (vp->v_type) { 177 case VREG: 178 return (nfs_readrpc(vp, uio)); 179 case VLNK: 180 return (nfs_readlinkrpc(vp, uio, cred)); 181 case VDIR: 182 break; 183 default: 184 printf(" NQNFSNONCACHE: type %x unexpected\n", 185 vp->v_type); 186 }; 187 } 188 baddr = (caddr_t)0; 189 switch (vp->v_type) { 190 case VREG: 191 nfsstats.biocache_reads++; 192 193 advice = IO_ADV_DECODE(ioflag); 194 error = 0; 195 while (uio->uio_resid > 0) { 196 void *win; 197 int flags; 198 vsize_t bytelen; 199 200 nfs_delayedtruncate(vp); 201 if (np->n_size <= uio->uio_offset) { 202 break; 203 } 204 bytelen = 205 MIN(np->n_size - uio->uio_offset, uio->uio_resid); 206 win = ubc_alloc(&vp->v_uobj, uio->uio_offset, 207 &bytelen, advice, UBC_READ); 208 error = uiomove(win, bytelen, uio); 209 flags = UBC_WANT_UNMAP(vp) ? UBC_UNMAP : 0; 210 ubc_release(win, flags); 211 if (error) { 212 /* 213 * XXXkludge 214 * the file has been truncated on the server. 215 * there isn't much we can do. 216 */ 217 if (uio->uio_offset >= np->n_size) { 218 /* end of file */ 219 error = 0; 220 } else { 221 break; 222 } 223 } 224 } 225 break; 226 227 case VLNK: 228 nfsstats.biocache_readlinks++; 229 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, l); 230 if (!bp) 231 return (EINTR); 232 if ((bp->b_flags & B_DONE) == 0) { 233 bp->b_flags |= B_READ; 234 error = nfs_doio(bp); 235 if (error) { 236 brelse(bp); 237 return (error); 238 } 239 } 240 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 241 got_buf = 1; 242 on = 0; 243 break; 244 case VDIR: 245 diragain: 246 nfsstats.biocache_readdirs++; 247 ndp = nfs_searchdircache(vp, uio->uio_offset, 248 (nmp->nm_flag & NFSMNT_XLATECOOKIE), 0); 249 if (!ndp) { 250 /* 251 * We've been handed a cookie that is not 252 * in the cache. If we're not translating 253 * 32 <-> 64, it may be a value that was 254 * flushed out of the cache because it grew 255 * too big. Let the server judge if it's 256 * valid or not. In the translation case, 257 * we have no way of validating this value, 258 * so punt. 259 */ 260 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) 261 return (EINVAL); 262 ndp = nfs_enterdircache(vp, uio->uio_offset, 263 uio->uio_offset, 0, 0); 264 } 265 266 if (NFS_EOFVALID(np) && 267 ndp->dc_cookie == np->n_direofoffset) { 268 nfs_putdircache(np, ndp); 269 nfsstats.direofcache_hits++; 270 return (0); 271 } 272 273 bp = nfs_getcacheblk(vp, NFSDC_BLKNO(ndp), NFS_DIRBLKSIZ, l); 274 if (!bp) 275 return (EINTR); 276 if ((bp->b_flags & B_DONE) == 0) { 277 bp->b_flags |= B_READ; 278 bp->b_dcookie = ndp->dc_blkcookie; 279 error = nfs_doio(bp); 280 if (error) { 281 /* 282 * Yuck! The directory has been modified on the 283 * server. Punt and let the userland code 284 * deal with it. 285 */ 286 nfs_putdircache(np, ndp); 287 brelse(bp); 288 if (error == NFSERR_BAD_COOKIE) { 289 nfs_invaldircache(vp, 0); 290 nfs_vinvalbuf(vp, 0, cred, l, 1); 291 error = EINVAL; 292 } 293 return (error); 294 } 295 } 296 297 /* 298 * Just return if we hit EOF right away with this 299 * block. Always check here, because direofoffset 300 * may have been set by an nfsiod since the last 301 * check. 302 * 303 * also, empty block implies EOF. 304 */ 305 306 if (bp->b_bcount == bp->b_resid || 307 (NFS_EOFVALID(np) && 308 ndp->dc_blkcookie == np->n_direofoffset)) { 309 KASSERT(bp->b_bcount != bp->b_resid || 310 ndp->dc_blkcookie == bp->b_dcookie); 311 nfs_putdircache(np, ndp); 312 bp->b_flags |= B_NOCACHE; 313 brelse(bp); 314 return 0; 315 } 316 317 /* 318 * Find the entry we were looking for in the block. 319 */ 320 321 en = ndp->dc_entry; 322 323 pdp = dp = (struct dirent *)bp->b_data; 324 edp = (struct dirent *)(void *)(bp->b_data + bp->b_bcount - 325 bp->b_resid); 326 enn = 0; 327 while (enn < en && dp < edp) { 328 pdp = dp; 329 dp = _DIRENT_NEXT(dp); 330 enn++; 331 } 332 333 /* 334 * If the entry number was bigger than the number of 335 * entries in the block, or the cookie of the previous 336 * entry doesn't match, the directory cache is 337 * stale. Flush it and try again (i.e. go to 338 * the server). 339 */ 340 if (dp >= edp || (struct dirent *)_DIRENT_NEXT(dp) > edp || 341 (en > 0 && NFS_GETCOOKIE(pdp) != ndp->dc_cookie)) { 342 #ifdef DEBUG 343 printf("invalid cache: %p %p %p off %lx %lx\n", 344 pdp, dp, edp, 345 (unsigned long)uio->uio_offset, 346 (unsigned long)NFS_GETCOOKIE(pdp)); 347 #endif 348 nfs_putdircache(np, ndp); 349 brelse(bp); 350 nfs_invaldircache(vp, 0); 351 nfs_vinvalbuf(vp, 0, cred, l, 0); 352 goto diragain; 353 } 354 355 on = (caddr_t)dp - bp->b_data; 356 357 /* 358 * Cache all entries that may be exported to the 359 * user, as they may be thrown back at us. The 360 * NFSBIO_CACHECOOKIES flag indicates that all 361 * entries are being 'exported', so cache them all. 362 */ 363 364 if (en == 0 && pdp == dp) { 365 dp = _DIRENT_NEXT(dp); 366 enn++; 367 } 368 369 if (uio->uio_resid < (bp->b_bcount - bp->b_resid - on)) { 370 n = uio->uio_resid; 371 enough = 1; 372 } else 373 n = bp->b_bcount - bp->b_resid - on; 374 375 ep = (struct dirent *)(void *)(bp->b_data + on + n); 376 377 /* 378 * Find last complete entry to copy, caching entries 379 * (if requested) as we go. 380 */ 381 382 while (dp < ep && (struct dirent *)_DIRENT_NEXT(dp) <= ep) { 383 if (cflag & NFSBIO_CACHECOOKIES) { 384 nndp = nfs_enterdircache(vp, NFS_GETCOOKIE(pdp), 385 ndp->dc_blkcookie, enn, bp->b_lblkno); 386 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 387 NFS_STASHCOOKIE32(pdp, 388 nndp->dc_cookie32); 389 } 390 nfs_putdircache(np, nndp); 391 } 392 pdp = dp; 393 dp = _DIRENT_NEXT(dp); 394 enn++; 395 } 396 nfs_putdircache(np, ndp); 397 398 /* 399 * If the last requested entry was not the last in the 400 * buffer (happens if NFS_DIRFRAGSIZ < NFS_DIRBLKSIZ), 401 * cache the cookie of the last requested one, and 402 * set of the offset to it. 403 */ 404 405 if ((on + n) < bp->b_bcount - bp->b_resid) { 406 curoff = NFS_GETCOOKIE(pdp); 407 nndp = nfs_enterdircache(vp, curoff, ndp->dc_blkcookie, 408 enn, bp->b_lblkno); 409 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 410 NFS_STASHCOOKIE32(pdp, nndp->dc_cookie32); 411 curoff = nndp->dc_cookie32; 412 } 413 nfs_putdircache(np, nndp); 414 } else 415 curoff = bp->b_dcookie; 416 417 /* 418 * Always cache the entry for the next block, 419 * so that readaheads can use it. 420 */ 421 nndp = nfs_enterdircache(vp, bp->b_dcookie, bp->b_dcookie, 0,0); 422 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 423 if (curoff == bp->b_dcookie) { 424 NFS_STASHCOOKIE32(pdp, nndp->dc_cookie32); 425 curoff = nndp->dc_cookie32; 426 } 427 } 428 429 n = (char *)_DIRENT_NEXT(pdp) - (bp->b_data + on); 430 431 /* 432 * If not eof and read aheads are enabled, start one. 433 * (You need the current block first, so that you have the 434 * directory offset cookie of the next block.) 435 */ 436 if (nfs_numasync > 0 && nmp->nm_readahead > 0 && 437 !NFS_EOFVALID(np) && !(np->n_flag & NQNFSNONCACHE)) { 438 rabp = nfs_getcacheblk(vp, NFSDC_BLKNO(nndp), 439 NFS_DIRBLKSIZ, l); 440 if (rabp) { 441 if ((rabp->b_flags & (B_DONE | B_DELWRI)) == 0) { 442 rabp->b_dcookie = nndp->dc_cookie; 443 rabp->b_flags |= (B_READ | B_ASYNC); 444 if (nfs_asyncio(rabp)) { 445 rabp->b_flags |= B_INVAL; 446 brelse(rabp); 447 } 448 } else 449 brelse(rabp); 450 } 451 } 452 nfs_putdircache(np, nndp); 453 got_buf = 1; 454 break; 455 default: 456 printf(" nfsbioread: type %x unexpected\n",vp->v_type); 457 break; 458 } 459 460 if (n > 0) { 461 if (!baddr) 462 baddr = bp->b_data; 463 error = uiomove(baddr + on, (int)n, uio); 464 } 465 switch (vp->v_type) { 466 case VREG: 467 break; 468 case VLNK: 469 n = 0; 470 break; 471 case VDIR: 472 if (np->n_flag & NQNFSNONCACHE) 473 bp->b_flags |= B_INVAL; 474 uio->uio_offset = curoff; 475 if (enough) 476 n = 0; 477 break; 478 default: 479 printf(" nfsbioread: type %x unexpected\n",vp->v_type); 480 } 481 if (got_buf) 482 brelse(bp); 483 } while (error == 0 && uio->uio_resid > 0 && n > 0); 484 return (error); 485 } 486 487 /* 488 * Vnode op for write using bio 489 */ 490 int 491 nfs_write(v) 492 void *v; 493 { 494 struct vop_write_args /* { 495 struct vnode *a_vp; 496 struct uio *a_uio; 497 int a_ioflag; 498 struct ucred *a_cred; 499 } */ *ap = v; 500 struct uio *uio = ap->a_uio; 501 struct lwp *l = uio->uio_lwp; 502 struct vnode *vp = ap->a_vp; 503 struct nfsnode *np = VTONFS(vp); 504 struct ucred *cred = ap->a_cred; 505 struct vattr vattr; 506 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 507 void *win; 508 voff_t oldoff, origoff; 509 vsize_t bytelen; 510 int flags, error = 0; 511 int ioflag = ap->a_ioflag; 512 int extended = 0, wrotedata = 0; 513 514 #ifdef DIAGNOSTIC 515 if (uio->uio_rw != UIO_WRITE) 516 panic("nfs_write mode"); 517 #endif 518 if (vp->v_type != VREG) 519 return (EIO); 520 if (np->n_flag & NWRITEERR) { 521 np->n_flag &= ~NWRITEERR; 522 return (np->n_error); 523 } 524 #ifndef NFS_V2_ONLY 525 if ((nmp->nm_flag & NFSMNT_NFSV3) && 526 !(nmp->nm_iflag & NFSMNT_GOTFSINFO)) 527 (void)nfs_fsinfo(nmp, vp, cred, l); 528 #endif 529 if (ioflag & (IO_APPEND | IO_SYNC)) { 530 if (np->n_flag & NMODIFIED) { 531 NFS_INVALIDATE_ATTRCACHE(np); 532 error = nfs_vinvalbuf(vp, V_SAVE, cred, l, 1); 533 if (error) 534 return (error); 535 } 536 if (ioflag & IO_APPEND) { 537 NFS_INVALIDATE_ATTRCACHE(np); 538 error = VOP_GETATTR(vp, &vattr, cred, l); 539 if (error) 540 return (error); 541 uio->uio_offset = np->n_size; 542 } 543 } 544 if (uio->uio_offset < 0) 545 return (EINVAL); 546 if ((uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 547 return (EFBIG); 548 if (uio->uio_resid == 0) 549 return (0); 550 /* 551 * Maybe this should be above the vnode op call, but so long as 552 * file servers have no limits, i don't think it matters 553 */ 554 if (l && l->l_proc && uio->uio_offset + uio->uio_resid > 555 l->l_proc->p_rlimit[RLIMIT_FSIZE].rlim_cur) { 556 psignal(l->l_proc, SIGXFSZ); 557 return (EFBIG); 558 } 559 560 if ((np->n_flag & NQNFSNONCACHE) && uio->uio_iovcnt == 1) { 561 int iomode = NFSV3WRITE_FILESYNC; 562 boolean_t stalewriteverf = FALSE; 563 564 lockmgr(&nmp->nm_writeverflock, LK_SHARED, NULL); 565 error = nfs_writerpc(vp, uio, &iomode, FALSE, &stalewriteverf); 566 lockmgr(&nmp->nm_writeverflock, LK_RELEASE, NULL); 567 if (stalewriteverf) 568 nfs_clearcommit(vp->v_mount); 569 return (error); 570 } 571 572 origoff = uio->uio_offset; 573 do { 574 boolean_t extending; /* if we are extending whole pages */ 575 u_quad_t oldsize; 576 oldoff = uio->uio_offset; 577 bytelen = uio->uio_resid; 578 579 #ifndef NFS_V2_ONLY 580 /* 581 * Check for a valid write lease. 582 */ 583 if ((nmp->nm_flag & NFSMNT_NQNFS) && 584 NQNFS_CKINVALID(vp, np, ND_WRITE)) { 585 do { 586 error = nqnfs_getlease(vp, ND_WRITE, cred, l); 587 } while (error == NQNFS_EXPIRED); 588 if (error) 589 return (error); 590 if (np->n_lrev != np->n_brev || 591 (np->n_flag & NQNFSNONCACHE)) { 592 error = nfs_vinvalbuf(vp, V_SAVE, cred, l, 1); 593 if (error) 594 return (error); 595 np->n_brev = np->n_lrev; 596 } 597 } 598 #endif 599 nfsstats.biocache_writes++; 600 601 oldsize = np->n_size; 602 np->n_flag |= NMODIFIED; 603 if (np->n_size < uio->uio_offset + bytelen) { 604 np->n_size = uio->uio_offset + bytelen; 605 } 606 extending = ((uio->uio_offset & PAGE_MASK) == 0 && 607 (bytelen & PAGE_MASK) == 0 && 608 uio->uio_offset >= vp->v_size); 609 win = ubc_alloc(&vp->v_uobj, uio->uio_offset, &bytelen, 610 UVM_ADV_NORMAL, 611 UBC_WRITE | (extending ? UBC_FAULTBUSY : 0)); 612 error = uiomove(win, bytelen, uio); 613 flags = UBC_WANT_UNMAP(vp) ? UBC_UNMAP : 0; 614 ubc_release(win, flags); 615 if (error) { 616 if (extending) { 617 /* 618 * backout size and free pages past eof. 619 */ 620 np->n_size = oldsize; 621 simple_lock(&vp->v_interlock); 622 (void)VOP_PUTPAGES(vp, round_page(vp->v_size), 623 0, PGO_SYNCIO | PGO_FREE); 624 } 625 break; 626 } 627 wrotedata = 1; 628 629 /* 630 * update UVM's notion of the size now that we've 631 * copied the data into the vnode's pages. 632 */ 633 634 if (vp->v_size < uio->uio_offset) { 635 uvm_vnp_setsize(vp, uio->uio_offset); 636 extended = 1; 637 } 638 639 if ((oldoff & ~(nmp->nm_wsize - 1)) != 640 (uio->uio_offset & ~(nmp->nm_wsize - 1))) { 641 simple_lock(&vp->v_interlock); 642 error = VOP_PUTPAGES(vp, 643 trunc_page(oldoff & ~(nmp->nm_wsize - 1)), 644 round_page((uio->uio_offset + nmp->nm_wsize - 1) & 645 ~(nmp->nm_wsize - 1)), PGO_CLEANIT); 646 } 647 } while (uio->uio_resid > 0); 648 if (wrotedata) 649 VN_KNOTE(vp, NOTE_WRITE | (extended ? NOTE_EXTEND : 0)); 650 if ((np->n_flag & NQNFSNONCACHE) || (ioflag & IO_SYNC)) { 651 simple_lock(&vp->v_interlock); 652 error = VOP_PUTPAGES(vp, 653 trunc_page(origoff & ~(nmp->nm_wsize - 1)), 654 round_page((uio->uio_offset + nmp->nm_wsize - 1) & 655 ~(nmp->nm_wsize - 1)), 656 PGO_CLEANIT | PGO_SYNCIO); 657 } 658 return error; 659 } 660 661 /* 662 * Get an nfs cache block. 663 * Allocate a new one if the block isn't currently in the cache 664 * and return the block marked busy. If the calling process is 665 * interrupted by a signal for an interruptible mount point, return 666 * NULL. 667 */ 668 struct buf * 669 nfs_getcacheblk(vp, bn, size, l) 670 struct vnode *vp; 671 daddr_t bn; 672 int size; 673 struct lwp *l; 674 { 675 struct buf *bp; 676 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 677 678 if (nmp->nm_flag & NFSMNT_INT) { 679 bp = getblk(vp, bn, size, PCATCH, 0); 680 while (bp == NULL) { 681 if (nfs_sigintr(nmp, NULL, l)) 682 return (NULL); 683 bp = getblk(vp, bn, size, 0, 2 * hz); 684 } 685 } else 686 bp = getblk(vp, bn, size, 0, 0); 687 return (bp); 688 } 689 690 /* 691 * Flush and invalidate all dirty buffers. If another process is already 692 * doing the flush, just wait for completion. 693 */ 694 int 695 nfs_vinvalbuf(vp, flags, cred, l, intrflg) 696 struct vnode *vp; 697 int flags; 698 struct ucred *cred; 699 struct lwp *l; 700 int intrflg; 701 { 702 struct nfsnode *np = VTONFS(vp); 703 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 704 int error = 0, slpflag, slptimeo; 705 706 if ((nmp->nm_flag & NFSMNT_INT) == 0) 707 intrflg = 0; 708 if (intrflg) { 709 slpflag = PCATCH; 710 slptimeo = 2 * hz; 711 } else { 712 slpflag = 0; 713 slptimeo = 0; 714 } 715 /* 716 * First wait for any other process doing a flush to complete. 717 */ 718 simple_lock(&vp->v_interlock); 719 while (np->n_flag & NFLUSHINPROG) { 720 np->n_flag |= NFLUSHWANT; 721 error = ltsleep(&np->n_flag, PRIBIO + 2, "nfsvinval", 722 slptimeo, &vp->v_interlock); 723 if (error && intrflg && nfs_sigintr(nmp, NULL, l)) { 724 simple_unlock(&vp->v_interlock); 725 return EINTR; 726 } 727 } 728 729 /* 730 * Now, flush as required. 731 */ 732 np->n_flag |= NFLUSHINPROG; 733 simple_unlock(&vp->v_interlock); 734 error = vinvalbuf(vp, flags, cred, l, slpflag, 0); 735 while (error) { 736 if (intrflg && nfs_sigintr(nmp, NULL, l)) { 737 error = EINTR; 738 break; 739 } 740 error = vinvalbuf(vp, flags, cred, l, 0, slptimeo); 741 } 742 simple_lock(&vp->v_interlock); 743 if (error == 0) 744 np->n_flag &= ~NMODIFIED; 745 np->n_flag &= ~NFLUSHINPROG; 746 if (np->n_flag & NFLUSHWANT) { 747 np->n_flag &= ~NFLUSHWANT; 748 wakeup(&np->n_flag); 749 } 750 simple_unlock(&vp->v_interlock); 751 return error; 752 } 753 754 /* 755 * nfs_flushstalebuf: flush cache if it's stale. 756 * 757 * => caller shouldn't own any pages or buffers which belong to the vnode. 758 */ 759 760 int 761 nfs_flushstalebuf(struct vnode *vp, struct ucred *cred, struct lwp *l, 762 int flags) 763 { 764 struct nfsnode *np = VTONFS(vp); 765 struct vattr vattr; 766 int error; 767 768 if (np->n_flag & NMODIFIED) { 769 if ((flags & NFS_FLUSHSTALEBUF_MYWRITE) == 0 770 || vp->v_type != VREG) { 771 error = nfs_vinvalbuf(vp, V_SAVE, cred, l, 1); 772 if (error) 773 return error; 774 if (vp->v_type == VDIR) { 775 nfs_invaldircache(vp, 0); 776 } 777 } else { 778 /* 779 * XXX assuming writes are ours. 780 */ 781 } 782 NFS_INVALIDATE_ATTRCACHE(np); 783 error = VOP_GETATTR(vp, &vattr, cred, l); 784 if (error) 785 return error; 786 np->n_mtime = vattr.va_mtime; 787 } else { 788 error = VOP_GETATTR(vp, &vattr, cred, l); 789 if (error) 790 return error; 791 if (timespeccmp(&np->n_mtime, &vattr.va_mtime, !=)) { 792 if (vp->v_type == VDIR) { 793 nfs_invaldircache(vp, 0); 794 } 795 error = nfs_vinvalbuf(vp, V_SAVE, cred, l, 1); 796 if (error) 797 return error; 798 np->n_mtime = vattr.va_mtime; 799 } 800 } 801 802 return error; 803 } 804 805 /* 806 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 807 * This is mainly to avoid queueing async I/O requests when the nfsiods 808 * are all hung on a dead server. 809 */ 810 811 int 812 nfs_asyncio(bp) 813 struct buf *bp; 814 { 815 int i; 816 struct nfsmount *nmp; 817 int gotiod, slpflag = 0, slptimeo = 0, error; 818 819 if (nfs_numasync == 0) 820 return (EIO); 821 822 nmp = VFSTONFS(bp->b_vp->v_mount); 823 again: 824 if (nmp->nm_flag & NFSMNT_INT) 825 slpflag = PCATCH; 826 gotiod = FALSE; 827 828 /* 829 * Find a free iod to process this request. 830 */ 831 832 for (i = 0; i < NFS_MAXASYNCDAEMON; i++) { 833 struct nfs_iod *iod = &nfs_asyncdaemon[i]; 834 835 simple_lock(&iod->nid_slock); 836 if (iod->nid_want) { 837 /* 838 * Found one, so wake it up and tell it which 839 * mount to process. 840 */ 841 iod->nid_want = NULL; 842 iod->nid_mount = nmp; 843 wakeup(&iod->nid_want); 844 simple_lock(&nmp->nm_slock); 845 simple_unlock(&iod->nid_slock); 846 nmp->nm_bufqiods++; 847 gotiod = TRUE; 848 break; 849 } 850 simple_unlock(&iod->nid_slock); 851 } 852 853 /* 854 * If none are free, we may already have an iod working on this mount 855 * point. If so, it will process our request. 856 */ 857 858 if (!gotiod) { 859 simple_lock(&nmp->nm_slock); 860 if (nmp->nm_bufqiods > 0) 861 gotiod = TRUE; 862 } 863 864 LOCK_ASSERT(simple_lock_held(&nmp->nm_slock)); 865 866 /* 867 * If we have an iod which can process the request, then queue 868 * the buffer. However, even if we have an iod, do not initiate 869 * queue cleaning if curproc is the pageout daemon. if the NFS mount 870 * is via local loopback, we may put curproc (pagedaemon) to sleep 871 * waiting for the writes to complete. But the server (ourself) 872 * may block the write, waiting for its (ie., our) pagedaemon 873 * to produce clean pages to handle the write: deadlock. 874 * XXX: start non-loopback mounts straight away? If "lots free", 875 * let pagedaemon start loopback writes anyway? 876 */ 877 if (gotiod) { 878 879 /* 880 * Ensure that the queue never grows too large. 881 */ 882 if (curproc == uvm.pagedaemon_proc) { 883 /* Enque for later, to avoid free-page deadlock */ 884 (void) 0; 885 } else while (nmp->nm_bufqlen >= 2*nfs_numasync) { 886 nmp->nm_bufqwant = TRUE; 887 error = ltsleep(&nmp->nm_bufq, 888 slpflag | PRIBIO | PNORELOCK, 889 "nfsaio", slptimeo, &nmp->nm_slock); 890 if (error) { 891 if (nfs_sigintr(nmp, NULL, curlwp)) 892 return (EINTR); 893 if (slpflag == PCATCH) { 894 slpflag = 0; 895 slptimeo = 2 * hz; 896 } 897 } 898 899 /* 900 * We might have lost our iod while sleeping, 901 * so check and loop if nescessary. 902 */ 903 904 if (nmp->nm_bufqiods == 0) 905 goto again; 906 907 simple_lock(&nmp->nm_slock); 908 } 909 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 910 nmp->nm_bufqlen++; 911 simple_unlock(&nmp->nm_slock); 912 return (0); 913 } 914 simple_unlock(&nmp->nm_slock); 915 916 /* 917 * All the iods are busy on other mounts, so return EIO to 918 * force the caller to process the i/o synchronously. 919 */ 920 921 return (EIO); 922 } 923 924 /* 925 * nfs_doio for read. 926 */ 927 static int 928 nfs_doio_read(bp, uiop) 929 struct buf *bp; 930 struct uio *uiop; 931 { 932 struct vnode *vp = bp->b_vp; 933 struct nfsnode *np = VTONFS(vp); 934 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 935 int error = 0; 936 937 uiop->uio_rw = UIO_READ; 938 switch (vp->v_type) { 939 case VREG: 940 nfsstats.read_bios++; 941 error = nfs_readrpc(vp, uiop); 942 if (!error && uiop->uio_resid) { 943 int diff, len; 944 945 /* 946 * If uio_resid > 0, there is a hole in the file and 947 * no writes after the hole have been pushed to 948 * the server yet or the file has been truncated 949 * on the server. 950 * Just zero fill the rest of the valid area. 951 */ 952 953 KASSERT(vp->v_size >= 954 uiop->uio_offset + uiop->uio_resid); 955 diff = bp->b_bcount - uiop->uio_resid; 956 len = uiop->uio_resid; 957 memset((char *)bp->b_data + diff, 0, len); 958 uiop->uio_resid = 0; 959 } 960 if (uiop->uio_lwp && (vp->v_flag & VTEXT) && 961 (((nmp->nm_flag & NFSMNT_NQNFS) && 962 NQNFS_CKINVALID(vp, np, ND_READ) && 963 np->n_lrev != np->n_brev) || 964 (!(nmp->nm_flag & NFSMNT_NQNFS) && 965 timespeccmp(&np->n_mtime, &np->n_vattr->va_mtime, !=)))) { 966 killproc(uiop->uio_lwp->l_proc, "process text file was modified"); 967 #if 0 /* XXX NJWLWP */ 968 uiop->uio_lwp->l_proc->p_holdcnt++; 969 #endif 970 } 971 break; 972 case VLNK: 973 KASSERT(uiop->uio_offset == (off_t)0); 974 nfsstats.readlink_bios++; 975 error = nfs_readlinkrpc(vp, uiop, np->n_rcred); 976 break; 977 case VDIR: 978 nfsstats.readdir_bios++; 979 uiop->uio_offset = bp->b_dcookie; 980 #ifndef NFS_V2_ONLY 981 if (nmp->nm_flag & NFSMNT_RDIRPLUS) { 982 error = nfs_readdirplusrpc(vp, uiop, 983 curlwp->l_proc->p_ucred); 984 if (error == NFSERR_NOTSUPP) 985 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 986 } 987 #else 988 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 989 #endif 990 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 991 error = nfs_readdirrpc(vp, uiop, 992 curlwp->l_proc->p_ucred); 993 if (!error) { 994 bp->b_dcookie = uiop->uio_offset; 995 } 996 break; 997 default: 998 printf("nfs_doio: type %x unexpected\n", vp->v_type); 999 break; 1000 } 1001 if (error) { 1002 bp->b_flags |= B_ERROR; 1003 bp->b_error = error; 1004 } 1005 return error; 1006 } 1007 1008 /* 1009 * nfs_doio for write. 1010 */ 1011 static int 1012 nfs_doio_write(bp, uiop) 1013 struct buf *bp; 1014 struct uio *uiop; 1015 { 1016 struct vnode *vp = bp->b_vp; 1017 struct nfsnode *np = VTONFS(vp); 1018 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1019 int iomode; 1020 boolean_t stalewriteverf = FALSE; 1021 int i, npages = (bp->b_bcount + PAGE_SIZE - 1) >> PAGE_SHIFT; 1022 struct vm_page *pgs[npages]; 1023 #ifndef NFS_V2_ONLY 1024 boolean_t needcommit = TRUE; /* need only COMMIT RPC */ 1025 #else 1026 boolean_t needcommit = FALSE; /* need only COMMIT RPC */ 1027 #endif 1028 boolean_t pageprotected; 1029 struct uvm_object *uobj = &vp->v_uobj; 1030 int error; 1031 off_t off, cnt; 1032 1033 if ((bp->b_flags & B_ASYNC) != 0 && NFS_ISV3(vp)) { 1034 iomode = NFSV3WRITE_UNSTABLE; 1035 } else { 1036 iomode = NFSV3WRITE_FILESYNC; 1037 } 1038 1039 #ifndef NFS_V2_ONLY 1040 again: 1041 #endif 1042 lockmgr(&nmp->nm_writeverflock, LK_SHARED, NULL); 1043 1044 for (i = 0; i < npages; i++) { 1045 pgs[i] = uvm_pageratop((vaddr_t)bp->b_data + (i << PAGE_SHIFT)); 1046 if (pgs[i]->uobject == uobj && 1047 pgs[i]->offset == uiop->uio_offset + (i << PAGE_SHIFT)) { 1048 KASSERT(pgs[i]->flags & PG_BUSY); 1049 /* 1050 * this page belongs to our object. 1051 */ 1052 simple_lock(&uobj->vmobjlock); 1053 /* 1054 * write out the page stably if it's about to 1055 * be released because we can't resend it 1056 * on the server crash. 1057 * 1058 * XXX assuming PG_RELEASE|PG_PAGEOUT won't be 1059 * changed until unbusy the page. 1060 */ 1061 if (pgs[i]->flags & (PG_RELEASED|PG_PAGEOUT)) 1062 iomode = NFSV3WRITE_FILESYNC; 1063 /* 1064 * if we met a page which hasn't been sent yet, 1065 * we need do WRITE RPC. 1066 */ 1067 if ((pgs[i]->flags & PG_NEEDCOMMIT) == 0) 1068 needcommit = FALSE; 1069 simple_unlock(&uobj->vmobjlock); 1070 } else { 1071 iomode = NFSV3WRITE_FILESYNC; 1072 needcommit = FALSE; 1073 } 1074 } 1075 if (!needcommit && iomode == NFSV3WRITE_UNSTABLE) { 1076 simple_lock(&uobj->vmobjlock); 1077 for (i = 0; i < npages; i++) { 1078 pgs[i]->flags |= PG_NEEDCOMMIT | PG_RDONLY; 1079 pmap_page_protect(pgs[i], VM_PROT_READ); 1080 } 1081 simple_unlock(&uobj->vmobjlock); 1082 pageprotected = TRUE; /* pages can't be modified during i/o. */ 1083 } else 1084 pageprotected = FALSE; 1085 1086 /* 1087 * Send the data to the server if necessary, 1088 * otherwise just send a commit rpc. 1089 */ 1090 #ifndef NFS_V2_ONLY 1091 if (needcommit) { 1092 1093 /* 1094 * If the buffer is in the range that we already committed, 1095 * there's nothing to do. 1096 * 1097 * If it's in the range that we need to commit, push the 1098 * whole range at once, otherwise only push the buffer. 1099 * In both these cases, acquire the commit lock to avoid 1100 * other processes modifying the range. 1101 */ 1102 1103 off = uiop->uio_offset; 1104 cnt = bp->b_bcount; 1105 lockmgr(&np->n_commitlock, LK_EXCLUSIVE, NULL); 1106 if (!nfs_in_committed_range(vp, off, bp->b_bcount)) { 1107 boolean_t pushedrange; 1108 if (nfs_in_tobecommitted_range(vp, off, bp->b_bcount)) { 1109 pushedrange = TRUE; 1110 off = np->n_pushlo; 1111 cnt = np->n_pushhi - np->n_pushlo; 1112 } else { 1113 pushedrange = FALSE; 1114 } 1115 error = nfs_commit(vp, off, cnt, curlwp); 1116 if (error == 0) { 1117 if (pushedrange) { 1118 nfs_merge_commit_ranges(vp); 1119 } else { 1120 nfs_add_committed_range(vp, off, cnt); 1121 } 1122 } 1123 } else { 1124 error = 0; 1125 } 1126 lockmgr(&np->n_commitlock, LK_RELEASE, NULL); 1127 lockmgr(&nmp->nm_writeverflock, LK_RELEASE, NULL); 1128 if (!error) { 1129 /* 1130 * pages are now on stable storage. 1131 */ 1132 uiop->uio_resid = 0; 1133 simple_lock(&uobj->vmobjlock); 1134 for (i = 0; i < npages; i++) { 1135 pgs[i]->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY); 1136 } 1137 simple_unlock(&uobj->vmobjlock); 1138 return 0; 1139 } else if (error == NFSERR_STALEWRITEVERF) { 1140 nfs_clearcommit(vp->v_mount); 1141 goto again; 1142 } 1143 if (error) { 1144 bp->b_flags |= B_ERROR; 1145 bp->b_error = np->n_error = error; 1146 np->n_flag |= NWRITEERR; 1147 } 1148 return error; 1149 } 1150 #endif 1151 off = uiop->uio_offset; 1152 cnt = bp->b_bcount; 1153 uiop->uio_rw = UIO_WRITE; 1154 nfsstats.write_bios++; 1155 error = nfs_writerpc(vp, uiop, &iomode, pageprotected, &stalewriteverf); 1156 #ifndef NFS_V2_ONLY 1157 if (!error && iomode == NFSV3WRITE_UNSTABLE) { 1158 /* 1159 * we need to commit pages later. 1160 */ 1161 lockmgr(&np->n_commitlock, LK_EXCLUSIVE, NULL); 1162 nfs_add_tobecommitted_range(vp, off, cnt); 1163 /* 1164 * if there can be too many uncommitted pages, commit them now. 1165 */ 1166 if (np->n_pushhi - np->n_pushlo > nfs_commitsize) { 1167 off = np->n_pushlo; 1168 cnt = nfs_commitsize >> 1; 1169 error = nfs_commit(vp, off, cnt, curlwp); 1170 if (!error) { 1171 nfs_add_committed_range(vp, off, cnt); 1172 nfs_del_tobecommitted_range(vp, off, cnt); 1173 } 1174 if (error == NFSERR_STALEWRITEVERF) { 1175 stalewriteverf = TRUE; 1176 error = 0; /* it isn't a real error */ 1177 } 1178 } else { 1179 /* 1180 * re-dirty pages so that they will be passed 1181 * to us later again. 1182 */ 1183 simple_lock(&uobj->vmobjlock); 1184 for (i = 0; i < npages; i++) { 1185 pgs[i]->flags &= ~PG_CLEAN; 1186 } 1187 simple_unlock(&uobj->vmobjlock); 1188 } 1189 lockmgr(&np->n_commitlock, LK_RELEASE, NULL); 1190 } else 1191 #endif 1192 if (!error) { 1193 /* 1194 * pages are now on stable storage. 1195 */ 1196 lockmgr(&np->n_commitlock, LK_EXCLUSIVE, NULL); 1197 nfs_del_committed_range(vp, off, cnt); 1198 lockmgr(&np->n_commitlock, LK_RELEASE, NULL); 1199 simple_lock(&uobj->vmobjlock); 1200 for (i = 0; i < npages; i++) { 1201 pgs[i]->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY); 1202 } 1203 simple_unlock(&uobj->vmobjlock); 1204 } else { 1205 /* 1206 * we got an error. 1207 */ 1208 bp->b_flags |= B_ERROR; 1209 bp->b_error = np->n_error = error; 1210 np->n_flag |= NWRITEERR; 1211 } 1212 1213 lockmgr(&nmp->nm_writeverflock, LK_RELEASE, NULL); 1214 1215 if (stalewriteverf) { 1216 nfs_clearcommit(vp->v_mount); 1217 } 1218 return error; 1219 } 1220 1221 /* 1222 * nfs_doio for B_PHYS. 1223 */ 1224 static int 1225 nfs_doio_phys(bp, uiop) 1226 struct buf *bp; 1227 struct uio *uiop; 1228 { 1229 struct vnode *vp = bp->b_vp; 1230 int error; 1231 1232 uiop->uio_offset = ((off_t)bp->b_blkno) << DEV_BSHIFT; 1233 if (bp->b_flags & B_READ) { 1234 uiop->uio_rw = UIO_READ; 1235 nfsstats.read_physios++; 1236 error = nfs_readrpc(vp, uiop); 1237 } else { 1238 int iomode = NFSV3WRITE_DATASYNC; 1239 boolean_t stalewriteverf; 1240 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1241 1242 uiop->uio_rw = UIO_WRITE; 1243 nfsstats.write_physios++; 1244 lockmgr(&nmp->nm_writeverflock, LK_SHARED, NULL); 1245 error = nfs_writerpc(vp, uiop, &iomode, FALSE, &stalewriteverf); 1246 lockmgr(&nmp->nm_writeverflock, LK_RELEASE, NULL); 1247 if (stalewriteverf) { 1248 nfs_clearcommit(bp->b_vp->v_mount); 1249 } 1250 } 1251 if (error) { 1252 bp->b_flags |= B_ERROR; 1253 bp->b_error = error; 1254 } 1255 return error; 1256 } 1257 1258 /* 1259 * Do an I/O operation to/from a cache block. This may be called 1260 * synchronously or from an nfsiod. 1261 */ 1262 int 1263 nfs_doio(bp) 1264 struct buf *bp; 1265 { 1266 int error; 1267 struct uio uio; 1268 struct uio *uiop = &uio; 1269 struct iovec io; 1270 UVMHIST_FUNC("nfs_doio"); UVMHIST_CALLED(ubchist); 1271 1272 uiop->uio_iov = &io; 1273 uiop->uio_iovcnt = 1; 1274 uiop->uio_segflg = UIO_SYSSPACE; 1275 uiop->uio_lwp = NULL; 1276 uiop->uio_offset = (((off_t)bp->b_blkno) << DEV_BSHIFT); 1277 io.iov_base = bp->b_data; 1278 io.iov_len = uiop->uio_resid = bp->b_bcount; 1279 1280 /* 1281 * Historically, paging was done with physio, but no more... 1282 */ 1283 if (bp->b_flags & B_PHYS) { 1284 /* 1285 * ...though reading /dev/drum still gets us here. 1286 */ 1287 error = nfs_doio_phys(bp, uiop); 1288 } else if (bp->b_flags & B_READ) { 1289 error = nfs_doio_read(bp, uiop); 1290 } else { 1291 error = nfs_doio_write(bp, uiop); 1292 } 1293 bp->b_resid = uiop->uio_resid; 1294 biodone(bp); 1295 return (error); 1296 } 1297 1298 /* 1299 * Vnode op for VM getpages. 1300 */ 1301 1302 int 1303 nfs_getpages(v) 1304 void *v; 1305 { 1306 struct vop_getpages_args /* { 1307 struct vnode *a_vp; 1308 voff_t a_offset; 1309 struct vm_page **a_m; 1310 int *a_count; 1311 int a_centeridx; 1312 vm_prot_t a_access_type; 1313 int a_advice; 1314 int a_flags; 1315 } */ *ap = v; 1316 1317 struct vnode *vp = ap->a_vp; 1318 struct uvm_object *uobj = &vp->v_uobj; 1319 struct nfsnode *np = VTONFS(vp); 1320 const int npages = *ap->a_count; 1321 struct vm_page *pg, **pgs, *opgs[npages]; 1322 off_t origoffset, len; 1323 int i, error; 1324 boolean_t v3 = NFS_ISV3(vp); 1325 boolean_t write = (ap->a_access_type & VM_PROT_WRITE) != 0; 1326 boolean_t locked = (ap->a_flags & PGO_LOCKED) != 0; 1327 1328 /* 1329 * call the genfs code to get the pages. `pgs' may be NULL 1330 * when doing read-ahead. 1331 */ 1332 1333 pgs = ap->a_m; 1334 if (write && locked && v3) { 1335 KASSERT(pgs != NULL); 1336 #ifdef DEBUG 1337 1338 /* 1339 * If PGO_LOCKED is set, real pages shouldn't exists 1340 * in the array. 1341 */ 1342 1343 for (i = 0; i < npages; i++) 1344 KDASSERT(pgs[i] == NULL || pgs[i] == PGO_DONTCARE); 1345 #endif 1346 memcpy(opgs, pgs, npages * sizeof(struct vm_pages *)); 1347 } 1348 error = genfs_getpages(v); 1349 if (error) { 1350 return (error); 1351 } 1352 1353 /* 1354 * for read faults where the nfs node is not yet marked NMODIFIED, 1355 * set PG_RDONLY on the pages so that we come back here if someone 1356 * tries to modify later via the mapping that will be entered for 1357 * this fault. 1358 */ 1359 1360 if (!write && (np->n_flag & NMODIFIED) == 0 && pgs != NULL) { 1361 if (!locked) { 1362 simple_lock(&uobj->vmobjlock); 1363 } 1364 for (i = 0; i < npages; i++) { 1365 pg = pgs[i]; 1366 if (pg == NULL || pg == PGO_DONTCARE) { 1367 continue; 1368 } 1369 pg->flags |= PG_RDONLY; 1370 } 1371 if (!locked) { 1372 simple_unlock(&uobj->vmobjlock); 1373 } 1374 } 1375 if (!write) { 1376 return (0); 1377 } 1378 1379 /* 1380 * this is a write fault, update the commit info. 1381 */ 1382 1383 origoffset = ap->a_offset; 1384 len = npages << PAGE_SHIFT; 1385 1386 if (v3) { 1387 error = lockmgr(&np->n_commitlock, 1388 LK_EXCLUSIVE | (locked ? LK_NOWAIT : 0), NULL); 1389 if (error) { 1390 KASSERT(locked != 0); 1391 1392 /* 1393 * Since PGO_LOCKED is set, we need to unbusy 1394 * all pages fetched by genfs_getpages() above, 1395 * tell the caller that there are no pages 1396 * available and put back original pgs array. 1397 */ 1398 1399 uvm_lock_pageq(); 1400 uvm_page_unbusy(pgs, npages); 1401 uvm_unlock_pageq(); 1402 *ap->a_count = 0; 1403 memcpy(pgs, opgs, 1404 npages * sizeof(struct vm_pages *)); 1405 return (error); 1406 } 1407 nfs_del_committed_range(vp, origoffset, len); 1408 nfs_del_tobecommitted_range(vp, origoffset, len); 1409 } 1410 np->n_flag |= NMODIFIED; 1411 if (!locked) { 1412 simple_lock(&uobj->vmobjlock); 1413 } 1414 for (i = 0; i < npages; i++) { 1415 pg = pgs[i]; 1416 if (pg == NULL || pg == PGO_DONTCARE) { 1417 continue; 1418 } 1419 pg->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY); 1420 } 1421 if (!locked) { 1422 simple_unlock(&uobj->vmobjlock); 1423 } 1424 if (v3) { 1425 lockmgr(&np->n_commitlock, LK_RELEASE, NULL); 1426 } 1427 return (0); 1428 } 1429