nfs_bio.c revision 1.44
1 /* $NetBSD: nfs_bio.c,v 1.44 1998/08/09 21:19:49 perry 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. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95 39 */ 40 41 #include "opt_uvm.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/trace.h> 51 #include <sys/mount.h> 52 #include <sys/kernel.h> 53 #include <sys/namei.h> 54 #include <sys/dirent.h> 55 56 #include <vm/vm.h> 57 58 #if defined(UVM) 59 #include <uvm/uvm_extern.h> 60 #endif 61 62 #include <nfs/rpcv2.h> 63 #include <nfs/nfsproto.h> 64 #include <nfs/nfs.h> 65 #include <nfs/nfsmount.h> 66 #include <nfs/nqnfs.h> 67 #include <nfs/nfsnode.h> 68 #include <nfs/nfs_var.h> 69 70 extern int nfs_numasync; 71 extern struct nfsstats nfsstats; 72 73 /* 74 * Vnode op for read using bio 75 * Any similarity to readip() is purely coincidental 76 */ 77 int 78 nfs_bioread(vp, uio, ioflag, cred, cflag) 79 register struct vnode *vp; 80 register struct uio *uio; 81 int ioflag, cflag; 82 struct ucred *cred; 83 { 84 register struct nfsnode *np = VTONFS(vp); 85 register int biosize, diff; 86 struct buf *bp = NULL, *rabp; 87 struct vattr vattr; 88 struct proc *p; 89 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 90 struct nfsdircache *ndp = NULL, *nndp = NULL; 91 daddr_t lbn, bn, rabn; 92 caddr_t baddr, ep, edp; 93 int got_buf = 0, nra, error = 0, n = 0, on = 0, not_readin, en, enn; 94 int enough = 0; 95 struct dirent *dp, *pdp; 96 off_t curoff = 0, offdiff; 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 if ((nmp->nm_flag & NFSMNT_NFSV3) && 108 !(nmp->nm_iflag & NFSMNT_GOTFSINFO)) 109 (void)nfs_fsinfo(nmp, vp, cred, p); 110 if (vp->v_type != VDIR && 111 (uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 112 return (EFBIG); 113 biosize = nmp->nm_rsize; 114 /* 115 * For nfs, cache consistency can only be maintained approximately. 116 * Although RFC1094 does not specify the criteria, the following is 117 * believed to be compatible with the reference port. 118 * For nqnfs, full cache consistency is maintained within the loop. 119 * For nfs: 120 * If the file's modify time on the server has changed since the 121 * last read rpc or you have written to the file, 122 * you may have lost data cache consistency with the 123 * server, so flush all of the file's data out of the cache. 124 * Then force a getattr rpc to ensure that you have up to date 125 * attributes. 126 * NB: This implies that cache data can be read when up to 127 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 128 * attributes this could be forced by setting n_attrstamp to 0 before 129 * the VOP_GETATTR() call. 130 */ 131 if ((nmp->nm_flag & NFSMNT_NQNFS) == 0 && vp->v_type != VLNK) { 132 if (np->n_flag & NMODIFIED) { 133 if (vp->v_type != VREG) { 134 if (vp->v_type != VDIR) 135 panic("nfs: bioread, not dir"); 136 nfs_invaldircache(vp, 0); 137 np->n_direofoffset = 0; 138 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 139 if (error) 140 return (error); 141 } 142 np->n_attrstamp = 0; 143 error = VOP_GETATTR(vp, &vattr, cred, p); 144 if (error) 145 return (error); 146 np->n_mtime = vattr.va_mtime.tv_sec; 147 } else { 148 error = VOP_GETATTR(vp, &vattr, cred, p); 149 if (error) 150 return (error); 151 if (np->n_mtime != vattr.va_mtime.tv_sec) { 152 if (vp->v_type == VDIR) { 153 nfs_invaldircache(vp, 0); 154 np->n_direofoffset = 0; 155 } 156 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 157 if (error) 158 return (error); 159 np->n_mtime = vattr.va_mtime.tv_sec; 160 } 161 } 162 } 163 do { 164 165 /* 166 * Get a valid lease. If cached data is stale, flush it. 167 */ 168 if (nmp->nm_flag & NFSMNT_NQNFS) { 169 if (NQNFS_CKINVALID(vp, np, ND_READ)) { 170 do { 171 error = nqnfs_getlease(vp, ND_READ, cred, p); 172 } while (error == NQNFS_EXPIRED); 173 if (error) 174 return (error); 175 if (np->n_lrev != np->n_brev || 176 (np->n_flag & NQNFSNONCACHE) || 177 ((np->n_flag & NMODIFIED) && vp->v_type == VDIR)) { 178 if (vp->v_type == VDIR) { 179 nfs_invaldircache(vp, 0); 180 np->n_direofoffset = 0; 181 } 182 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 183 if (error) 184 return (error); 185 np->n_brev = np->n_lrev; 186 } 187 } else if (vp->v_type == VDIR && (np->n_flag & NMODIFIED)) { 188 nfs_invaldircache(vp, 0); 189 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 190 np->n_direofoffset = 0; 191 if (error) 192 return (error); 193 } 194 } 195 /* 196 * Don't cache symlinks. 197 */ 198 if (np->n_flag & NQNFSNONCACHE 199 || ((vp->v_flag & VROOT) && vp->v_type == VLNK)) { 200 switch (vp->v_type) { 201 case VREG: 202 return (nfs_readrpc(vp, uio, cred)); 203 case VLNK: 204 return (nfs_readlinkrpc(vp, uio, cred)); 205 case VDIR: 206 break; 207 default: 208 printf(" NQNFSNONCACHE: type %x unexpected\n", 209 vp->v_type); 210 }; 211 } 212 baddr = (caddr_t)0; 213 switch (vp->v_type) { 214 case VREG: 215 nfsstats.biocache_reads++; 216 lbn = uio->uio_offset / biosize; 217 on = uio->uio_offset & (biosize - 1); 218 bn = lbn * (biosize / DEV_BSIZE); 219 not_readin = 1; 220 221 /* 222 * Start the read ahead(s), as required. 223 */ 224 if (nfs_numasync > 0 && nmp->nm_readahead > 0 && 225 lbn - 1 == vp->v_lastr) { 226 for (nra = 0; nra < nmp->nm_readahead && 227 (lbn + 1 + nra) * biosize < np->n_size; nra++) { 228 rabn = (lbn + 1 + nra) * (biosize / DEV_BSIZE); 229 if (!incore(vp, rabn)) { 230 rabp = nfs_getcacheblk(vp, rabn, biosize, p); 231 if (!rabp) 232 return (EINTR); 233 if ((rabp->b_flags & (B_DELWRI | B_DONE)) == 0) { 234 rabp->b_flags |= (B_READ | B_ASYNC); 235 if (nfs_asyncio(rabp, cred)) { 236 rabp->b_flags |= B_INVAL; 237 brelse(rabp); 238 } 239 } else 240 brelse(rabp); 241 } 242 } 243 } 244 245 /* 246 * If the block is in the cache and has the required data 247 * in a valid region, just copy it out. 248 * Otherwise, get the block and write back/read in, 249 * as required. 250 */ 251 if ((bp = incore(vp, bn)) && 252 (bp->b_flags & (B_BUSY | B_WRITEINPROG)) == 253 (B_BUSY | B_WRITEINPROG)) 254 got_buf = 0; 255 else { 256 again: 257 bp = nfs_getcacheblk(vp, bn, biosize, p); 258 if (!bp) 259 return (EINTR); 260 got_buf = 1; 261 if ((bp->b_flags & (B_DONE | B_DELWRI)) == 0) { 262 bp->b_flags |= B_READ; 263 not_readin = 0; 264 error = nfs_doio(bp, cred, p); 265 if (error) { 266 brelse(bp); 267 return (error); 268 } 269 } 270 } 271 n = min((unsigned)(biosize - on), uio->uio_resid); 272 offdiff = np->n_size - uio->uio_offset; 273 if (offdiff < (off_t)n) 274 n = (int)offdiff; 275 if (not_readin && n > 0) { 276 if (on < bp->b_validoff || (on + n) > bp->b_validend) { 277 if (!got_buf) { 278 bp = nfs_getcacheblk(vp, bn, biosize, p); 279 if (!bp) 280 return (EINTR); 281 got_buf = 1; 282 } 283 bp->b_flags |= B_INVAFTERWRITE; 284 if (bp->b_dirtyend > 0) { 285 if ((bp->b_flags & B_DELWRI) == 0) 286 panic("nfsbioread"); 287 if (VOP_BWRITE(bp) == EINTR) 288 return (EINTR); 289 } else 290 brelse(bp); 291 goto again; 292 } 293 } 294 vp->v_lastr = lbn; 295 diff = (on >= bp->b_validend) ? 0 : (bp->b_validend - on); 296 if (diff < n) 297 n = diff; 298 break; 299 case VLNK: 300 nfsstats.biocache_readlinks++; 301 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, p); 302 if (!bp) 303 return (EINTR); 304 if ((bp->b_flags & B_DONE) == 0) { 305 bp->b_flags |= B_READ; 306 error = nfs_doio(bp, cred, p); 307 if (error) { 308 brelse(bp); 309 return (error); 310 } 311 } 312 n = min(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 313 got_buf = 1; 314 on = 0; 315 break; 316 case VDIR: 317 diragain: 318 nfsstats.biocache_readdirs++; 319 ndp = nfs_searchdircache(vp, uio->uio_offset, 320 (nmp->nm_flag & NFSMNT_XLATECOOKIE), 0); 321 if (!ndp) { 322 /* 323 * We've been handed a cookie that is not 324 * in the cache. If we're not translating 325 * 32 <-> 64, it may be a value that was 326 * flushed out of the cache because it grew 327 * too big. Let the server judge if it's 328 * valid or not. In the translation case, 329 * we have no way of validating this value, 330 * so punt. 331 */ 332 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) 333 return (EINVAL); 334 ndp = nfs_enterdircache(vp, uio->uio_offset, 335 uio->uio_offset, 0, 0); 336 } 337 338 if (uio->uio_offset != 0 && 339 ndp->dc_cookie == np->n_direofoffset) { 340 nfsstats.direofcache_hits++; 341 return (0); 342 } 343 344 bp = nfs_getcacheblk(vp, ndp->dc_blkno, NFS_DIRBLKSIZ, p); 345 if (!bp) 346 return (EINTR); 347 if ((bp->b_flags & B_DONE) == 0) { 348 bp->b_flags |= B_READ; 349 bp->b_dcookie = ndp->dc_blkcookie; 350 error = nfs_doio(bp, cred, p); 351 if (error) { 352 /* 353 * Yuck! The directory has been modified on the 354 * server. Punt and let the userland code 355 * deal with it. 356 */ 357 brelse(bp); 358 if (error == NFSERR_BAD_COOKIE) { 359 nfs_invaldircache(vp, 0); 360 nfs_vinvalbuf(vp, 0, cred, p, 1); 361 error = EINVAL; 362 } 363 return (error); 364 } 365 } 366 367 /* 368 * Just return if we hit EOF right away with this 369 * block. Always check here, because direofoffset 370 * may have been set by an nfsiod since the last 371 * check. 372 */ 373 if (np->n_direofoffset != 0 && 374 ndp->dc_blkcookie == np->n_direofoffset) { 375 brelse(bp); 376 return (0); 377 } 378 379 /* 380 * Find the entry we were looking for in the block. 381 */ 382 383 en = ndp->dc_entry; 384 385 pdp = dp = (struct dirent *)bp->b_data; 386 edp = bp->b_data + bp->b_validend; 387 enn = 0; 388 while (enn < en && (caddr_t)dp < edp) { 389 pdp = dp; 390 dp = (struct dirent *)((caddr_t)dp + dp->d_reclen); 391 enn++; 392 } 393 394 /* 395 * If the entry number was bigger than the number of 396 * entries in the block, or the cookie of the previous 397 * entry doesn't match, the directory cache is 398 * stale. Flush it and try again (i.e. go to 399 * the server). 400 */ 401 if ((caddr_t)dp >= edp || (caddr_t)dp + dp->d_reclen > edp || 402 (en > 0 && NFS_GETCOOKIE(pdp) != ndp->dc_cookie)) { 403 #ifdef DEBUG 404 printf("invalid cache: %p %p %p off %lx %lx\n", 405 pdp, dp, edp, 406 (unsigned long)uio->uio_offset, 407 (unsigned long)NFS_GETCOOKIE(pdp)); 408 #endif 409 brelse(bp); 410 nfs_invaldircache(vp, 0); 411 nfs_vinvalbuf(vp, 0, cred, p, 0); 412 goto diragain; 413 } 414 415 on = (caddr_t)dp - bp->b_data; 416 417 /* 418 * Cache all entries that may be exported to the 419 * user, as they may be thrown back at us. The 420 * NFSBIO_CACHECOOKIES flag indicates that all 421 * entries are being 'exported', so cache them all. 422 */ 423 424 if (en == 0 && pdp == dp) { 425 dp = (struct dirent *) 426 ((caddr_t)dp + dp->d_reclen); 427 enn++; 428 } 429 430 if (uio->uio_resid < (bp->b_validend - on)) { 431 n = uio->uio_resid; 432 enough = 1; 433 } else 434 n = bp->b_validend - on; 435 436 ep = bp->b_data + on + n; 437 438 /* 439 * Find last complete entry to copy, caching entries 440 * (if requested) as we go. 441 */ 442 443 while ((caddr_t)dp < ep && (caddr_t)dp + dp->d_reclen <= ep) { 444 if (cflag & NFSBIO_CACHECOOKIES) { 445 nndp = nfs_enterdircache(vp, NFS_GETCOOKIE(pdp), 446 ndp->dc_blkcookie, enn, bp->b_lblkno); 447 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 448 NFS_STASHCOOKIE32(pdp, 449 nndp->dc_cookie32); 450 } 451 } 452 pdp = dp; 453 dp = (struct dirent *)((caddr_t)dp + dp->d_reclen); 454 enn++; 455 } 456 457 /* 458 * If the last requested entry was not the last in the 459 * buffer (happens if NFS_DIRFRAGSIZ < NFS_DIRBLKSIZ), 460 * cache the cookie of the last requested one, and 461 * set of the offset to it. 462 */ 463 464 if ((on + n) < bp->b_validend) { 465 curoff = NFS_GETCOOKIE(pdp); 466 nndp = nfs_enterdircache(vp, curoff, ndp->dc_blkcookie, 467 enn, bp->b_lblkno); 468 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 469 NFS_STASHCOOKIE32(pdp, nndp->dc_cookie32); 470 curoff = nndp->dc_cookie32; 471 } 472 } else 473 curoff = bp->b_dcookie; 474 475 /* 476 * Always cache the entry for the next block, 477 * so that readaheads can use it. 478 */ 479 nndp = nfs_enterdircache(vp, bp->b_dcookie, bp->b_dcookie, 0,0); 480 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 481 if (curoff == bp->b_dcookie) { 482 NFS_STASHCOOKIE32(pdp, nndp->dc_cookie32); 483 curoff = nndp->dc_cookie32; 484 } 485 } 486 487 n = ((caddr_t)pdp + pdp->d_reclen) - (bp->b_data + on); 488 489 /* 490 * If not eof and read aheads are enabled, start one. 491 * (You need the current block first, so that you have the 492 * directory offset cookie of the next block.) 493 */ 494 if (nfs_numasync > 0 && nmp->nm_readahead > 0 && 495 np->n_direofoffset == 0 && !(np->n_flag & NQNFSNONCACHE)) { 496 rabp = nfs_getcacheblk(vp, nndp->dc_blkno, 497 NFS_DIRBLKSIZ, p); 498 if (rabp) { 499 if ((rabp->b_flags & (B_DONE | B_DELWRI)) == 0) { 500 rabp->b_dcookie = nndp->dc_cookie; 501 rabp->b_flags |= (B_READ | B_ASYNC); 502 if (nfs_asyncio(rabp, cred)) { 503 rabp->b_flags |= B_INVAL; 504 brelse(rabp); 505 } 506 } else 507 brelse(rabp); 508 } 509 } 510 got_buf = 1; 511 break; 512 default: 513 printf(" nfsbioread: type %x unexpected\n",vp->v_type); 514 break; 515 }; 516 517 if (n > 0) { 518 if (!baddr) 519 baddr = bp->b_data; 520 error = uiomove(baddr + on, (int)n, uio); 521 } 522 switch (vp->v_type) { 523 case VREG: 524 break; 525 case VLNK: 526 n = 0; 527 break; 528 case VDIR: 529 if (np->n_flag & NQNFSNONCACHE) 530 bp->b_flags |= B_INVAL; 531 uio->uio_offset = curoff; 532 if (enough) 533 n = 0; 534 break; 535 default: 536 printf(" nfsbioread: type %x unexpected\n",vp->v_type); 537 } 538 if (got_buf) 539 brelse(bp); 540 } while (error == 0 && uio->uio_resid > 0 && n > 0); 541 return (error); 542 } 543 544 /* 545 * Vnode op for write using bio 546 */ 547 int 548 nfs_write(v) 549 void *v; 550 { 551 struct vop_write_args /* { 552 struct vnode *a_vp; 553 struct uio *a_uio; 554 int a_ioflag; 555 struct ucred *a_cred; 556 } */ *ap = v; 557 register int biosize; 558 register struct uio *uio = ap->a_uio; 559 struct proc *p = uio->uio_procp; 560 register struct vnode *vp = ap->a_vp; 561 struct nfsnode *np = VTONFS(vp); 562 register struct ucred *cred = ap->a_cred; 563 int ioflag = ap->a_ioflag; 564 struct buf *bp; 565 struct vattr vattr; 566 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 567 daddr_t lbn, bn; 568 int n, on, error = 0, iomode, must_commit; 569 570 #ifdef DIAGNOSTIC 571 if (uio->uio_rw != UIO_WRITE) 572 panic("nfs_write mode"); 573 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) 574 panic("nfs_write proc"); 575 #endif 576 if (vp->v_type != VREG) 577 return (EIO); 578 if (np->n_flag & NWRITEERR) { 579 np->n_flag &= ~NWRITEERR; 580 return (np->n_error); 581 } 582 if ((nmp->nm_flag & NFSMNT_NFSV3) && 583 !(nmp->nm_iflag & NFSMNT_GOTFSINFO)) 584 (void)nfs_fsinfo(nmp, vp, cred, p); 585 if (ioflag & (IO_APPEND | IO_SYNC)) { 586 if (np->n_flag & NMODIFIED) { 587 np->n_attrstamp = 0; 588 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 589 if (error) 590 return (error); 591 } 592 if (ioflag & IO_APPEND) { 593 np->n_attrstamp = 0; 594 error = VOP_GETATTR(vp, &vattr, cred, p); 595 if (error) 596 return (error); 597 uio->uio_offset = np->n_size; 598 } 599 } 600 if (uio->uio_offset < 0) 601 return (EINVAL); 602 if ((uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 603 return (EFBIG); 604 if (uio->uio_resid == 0) 605 return (0); 606 /* 607 * Maybe this should be above the vnode op call, but so long as 608 * file servers have no limits, i don't think it matters 609 */ 610 if (p && uio->uio_offset + uio->uio_resid > 611 p->p_rlimit[RLIMIT_FSIZE].rlim_cur) { 612 psignal(p, SIGXFSZ); 613 return (EFBIG); 614 } 615 /* 616 * I use nm_rsize, not nm_wsize so that all buffer cache blocks 617 * will be the same size within a filesystem. nfs_writerpc will 618 * still use nm_wsize when sizing the rpc's. 619 */ 620 biosize = nmp->nm_rsize; 621 do { 622 623 /* 624 * XXX make sure we aren't cached in the VM page cache 625 */ 626 #if defined(UVM) 627 (void)uvm_vnp_uncache(vp); 628 #else 629 (void)vnode_pager_uncache(vp); 630 #endif 631 632 /* 633 * Check for a valid write lease. 634 */ 635 if ((nmp->nm_flag & NFSMNT_NQNFS) && 636 NQNFS_CKINVALID(vp, np, ND_WRITE)) { 637 do { 638 error = nqnfs_getlease(vp, ND_WRITE, cred, p); 639 } while (error == NQNFS_EXPIRED); 640 if (error) 641 return (error); 642 if (np->n_lrev != np->n_brev || 643 (np->n_flag & NQNFSNONCACHE)) { 644 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 645 if (error) 646 return (error); 647 np->n_brev = np->n_lrev; 648 } 649 } 650 if ((np->n_flag & NQNFSNONCACHE) && uio->uio_iovcnt == 1) { 651 iomode = NFSV3WRITE_FILESYNC; 652 error = nfs_writerpc(vp, uio, cred, &iomode, &must_commit); 653 if (must_commit) 654 nfs_clearcommit(vp->v_mount); 655 return (error); 656 } 657 nfsstats.biocache_writes++; 658 lbn = uio->uio_offset / biosize; 659 on = uio->uio_offset & (biosize-1); 660 n = min((unsigned)(biosize - on), uio->uio_resid); 661 bn = lbn * (biosize / DEV_BSIZE); 662 again: 663 bp = nfs_getcacheblk(vp, bn, biosize, p); 664 if (!bp) 665 return (EINTR); 666 if (bp->b_wcred == NOCRED) { 667 crhold(cred); 668 bp->b_wcred = cred; 669 } 670 np->n_flag |= NMODIFIED; 671 if (uio->uio_offset + n > np->n_size) { 672 np->n_size = uio->uio_offset + n; 673 #if defined(UVM) 674 uvm_vnp_setsize(vp, np->n_size); 675 #else 676 vnode_pager_setsize(vp, np->n_size); 677 #endif 678 } 679 680 /* 681 * If the new write will leave a contiguous dirty 682 * area, just update the b_dirtyoff and b_dirtyend, 683 * otherwise force a write rpc of the old dirty area. 684 */ 685 if (bp->b_dirtyend > 0 && 686 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 687 bp->b_proc = p; 688 if (VOP_BWRITE(bp) == EINTR) 689 return (EINTR); 690 goto again; 691 } 692 693 /* 694 * Check for valid write lease and get one as required. 695 * In case getblk() and/or bwrite() delayed us. 696 */ 697 if ((nmp->nm_flag & NFSMNT_NQNFS) && 698 NQNFS_CKINVALID(vp, np, ND_WRITE)) { 699 do { 700 error = nqnfs_getlease(vp, ND_WRITE, cred, p); 701 } while (error == NQNFS_EXPIRED); 702 if (error) { 703 brelse(bp); 704 return (error); 705 } 706 if (np->n_lrev != np->n_brev || 707 (np->n_flag & NQNFSNONCACHE)) { 708 brelse(bp); 709 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 710 if (error) 711 return (error); 712 np->n_brev = np->n_lrev; 713 goto again; 714 } 715 } 716 error = uiomove((char *)bp->b_data + on, n, uio); 717 if (error) { 718 bp->b_flags |= B_ERROR; 719 brelse(bp); 720 return (error); 721 } 722 if (bp->b_dirtyend > 0) { 723 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 724 bp->b_dirtyend = max((on + n), bp->b_dirtyend); 725 } else { 726 bp->b_dirtyoff = on; 727 bp->b_dirtyend = on + n; 728 } 729 if (bp->b_validend == 0 || bp->b_validend < bp->b_dirtyoff || 730 bp->b_validoff > bp->b_dirtyend) { 731 bp->b_validoff = bp->b_dirtyoff; 732 bp->b_validend = bp->b_dirtyend; 733 } else { 734 bp->b_validoff = min(bp->b_validoff, bp->b_dirtyoff); 735 bp->b_validend = max(bp->b_validend, bp->b_dirtyend); 736 } 737 738 /* 739 * Since this block is being modified, it must be written 740 * again and not just committed. 741 */ 742 bp->b_flags &= ~B_NEEDCOMMIT; 743 744 /* 745 * If the lease is non-cachable or IO_SYNC do bwrite(). 746 */ 747 if ((np->n_flag & NQNFSNONCACHE) || (ioflag & IO_SYNC)) { 748 bp->b_proc = p; 749 error = VOP_BWRITE(bp); 750 if (error) 751 return (error); 752 if (np->n_flag & NQNFSNONCACHE) { 753 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 754 if (error) 755 return (error); 756 } 757 } else if ((n + on) == biosize && 758 (nmp->nm_flag & NFSMNT_NQNFS) == 0) { 759 bp->b_proc = (struct proc *)0; 760 bp->b_flags |= B_ASYNC; 761 (void)nfs_writebp(bp, 0); 762 } else { 763 bdwrite(bp); 764 } 765 } while (uio->uio_resid > 0 && n > 0); 766 return (0); 767 } 768 769 /* 770 * Get an nfs cache block. 771 * Allocate a new one if the block isn't currently in the cache 772 * and return the block marked busy. If the calling process is 773 * interrupted by a signal for an interruptible mount point, return 774 * NULL. 775 */ 776 struct buf * 777 nfs_getcacheblk(vp, bn, size, p) 778 struct vnode *vp; 779 daddr_t bn; 780 int size; 781 struct proc *p; 782 { 783 register struct buf *bp; 784 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 785 786 if (nmp->nm_flag & NFSMNT_INT) { 787 bp = getblk(vp, bn, size, PCATCH, 0); 788 while (bp == (struct buf *)0) { 789 if (nfs_sigintr(nmp, (struct nfsreq *)0, p)) 790 return ((struct buf *)0); 791 bp = getblk(vp, bn, size, 0, 2 * hz); 792 } 793 } else 794 bp = getblk(vp, bn, size, 0, 0); 795 return (bp); 796 } 797 798 /* 799 * Flush and invalidate all dirty buffers. If another process is already 800 * doing the flush, just wait for completion. 801 */ 802 int 803 nfs_vinvalbuf(vp, flags, cred, p, intrflg) 804 struct vnode *vp; 805 int flags; 806 struct ucred *cred; 807 struct proc *p; 808 int intrflg; 809 { 810 register struct nfsnode *np = VTONFS(vp); 811 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 812 int error = 0, slpflag, slptimeo; 813 814 if ((nmp->nm_flag & NFSMNT_INT) == 0) 815 intrflg = 0; 816 if (intrflg) { 817 slpflag = PCATCH; 818 slptimeo = 2 * hz; 819 } else { 820 slpflag = 0; 821 slptimeo = 0; 822 } 823 /* 824 * First wait for any other process doing a flush to complete. 825 */ 826 while (np->n_flag & NFLUSHINPROG) { 827 np->n_flag |= NFLUSHWANT; 828 error = tsleep((caddr_t)&np->n_flag, PRIBIO + 2, "nfsvinval", 829 slptimeo); 830 if (error && intrflg && nfs_sigintr(nmp, (struct nfsreq *)0, p)) 831 return (EINTR); 832 } 833 834 /* 835 * Now, flush as required. 836 */ 837 np->n_flag |= NFLUSHINPROG; 838 error = vinvalbuf(vp, flags, cred, p, slpflag, 0); 839 while (error) { 840 if (intrflg && nfs_sigintr(nmp, (struct nfsreq *)0, p)) { 841 np->n_flag &= ~NFLUSHINPROG; 842 if (np->n_flag & NFLUSHWANT) { 843 np->n_flag &= ~NFLUSHWANT; 844 wakeup((caddr_t)&np->n_flag); 845 } 846 return (EINTR); 847 } 848 error = vinvalbuf(vp, flags, cred, p, 0, slptimeo); 849 } 850 np->n_flag &= ~(NMODIFIED | NFLUSHINPROG); 851 if (np->n_flag & NFLUSHWANT) { 852 np->n_flag &= ~NFLUSHWANT; 853 wakeup((caddr_t)&np->n_flag); 854 } 855 return (0); 856 } 857 858 /* 859 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 860 * This is mainly to avoid queueing async I/O requests when the nfsiods 861 * are all hung on a dead server. 862 */ 863 int 864 nfs_asyncio(bp, cred) 865 register struct buf *bp; 866 struct ucred *cred; 867 { 868 register int i; 869 register struct nfsmount *nmp; 870 int gotiod, slpflag = 0, slptimeo = 0, error; 871 872 if (nfs_numasync == 0) 873 return (EIO); 874 875 876 nmp = VFSTONFS(bp->b_vp->v_mount); 877 again: 878 if (nmp->nm_flag & NFSMNT_INT) 879 slpflag = PCATCH; 880 gotiod = FALSE; 881 882 /* 883 * Find a free iod to process this request. 884 */ 885 886 for (i = 0; i < NFS_MAXASYNCDAEMON; i++) 887 if (nfs_iodwant[i]) { 888 /* 889 * Found one, so wake it up and tell it which 890 * mount to process. 891 */ 892 nfs_iodwant[i] = (struct proc *)0; 893 nfs_iodmount[i] = nmp; 894 nmp->nm_bufqiods++; 895 wakeup((caddr_t)&nfs_iodwant[i]); 896 gotiod = TRUE; 897 break; 898 } 899 /* 900 * If none are free, we may already have an iod working on this mount 901 * point. If so, it will process our request. 902 */ 903 if (!gotiod && nmp->nm_bufqiods > 0) 904 gotiod = TRUE; 905 906 /* 907 * If we have an iod which can process the request, then queue 908 * the buffer. 909 */ 910 if (gotiod) { 911 /* 912 * Ensure that the queue never grows too large. 913 */ 914 while (nmp->nm_bufqlen >= 2*nfs_numasync) { 915 nmp->nm_bufqwant = TRUE; 916 error = tsleep(&nmp->nm_bufq, slpflag | PRIBIO, 917 "nfsaio", slptimeo); 918 if (error) { 919 if (nfs_sigintr(nmp, NULL, bp->b_proc)) 920 return (EINTR); 921 if (slpflag == PCATCH) { 922 slpflag = 0; 923 slptimeo = 2 * hz; 924 } 925 } 926 /* 927 * We might have lost our iod while sleeping, 928 * so check and loop if nescessary. 929 */ 930 if (nmp->nm_bufqiods == 0) 931 goto again; 932 } 933 934 if (bp->b_flags & B_READ) { 935 if (bp->b_rcred == NOCRED && cred != NOCRED) { 936 crhold(cred); 937 bp->b_rcred = cred; 938 } 939 } else { 940 bp->b_flags |= B_WRITEINPROG; 941 if (bp->b_wcred == NOCRED && cred != NOCRED) { 942 crhold(cred); 943 bp->b_wcred = cred; 944 } 945 } 946 947 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 948 nmp->nm_bufqlen++; 949 return (0); 950 } 951 952 /* 953 * All the iods are busy on other mounts, so return EIO to 954 * force the caller to process the i/o synchronously. 955 */ 956 return (EIO); 957 } 958 959 /* 960 * Do an I/O operation to/from a cache block. This may be called 961 * synchronously or from an nfsiod. 962 */ 963 int 964 nfs_doio(bp, cr, p) 965 register struct buf *bp; 966 struct ucred *cr; 967 struct proc *p; 968 { 969 register struct uio *uiop; 970 register struct vnode *vp; 971 struct nfsnode *np; 972 struct nfsmount *nmp; 973 int error = 0, diff, len, iomode, must_commit = 0; 974 struct uio uio; 975 struct iovec io; 976 977 vp = bp->b_vp; 978 np = VTONFS(vp); 979 nmp = VFSTONFS(vp->v_mount); 980 uiop = &uio; 981 uiop->uio_iov = &io; 982 uiop->uio_iovcnt = 1; 983 uiop->uio_segflg = UIO_SYSSPACE; 984 uiop->uio_procp = p; 985 986 /* 987 * Historically, paging was done with physio, but no more... 988 */ 989 if (bp->b_flags & B_PHYS) { 990 /* 991 * ...though reading /dev/drum still gets us here. 992 */ 993 io.iov_len = uiop->uio_resid = bp->b_bcount; 994 /* mapping was done by vmapbuf() */ 995 io.iov_base = bp->b_data; 996 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 997 if (bp->b_flags & B_READ) { 998 uiop->uio_rw = UIO_READ; 999 nfsstats.read_physios++; 1000 error = nfs_readrpc(vp, uiop, cr); 1001 } else { 1002 iomode = NFSV3WRITE_DATASYNC; 1003 uiop->uio_rw = UIO_WRITE; 1004 nfsstats.write_physios++; 1005 error = nfs_writerpc(vp, uiop, cr, &iomode, &must_commit); 1006 } 1007 if (error) { 1008 bp->b_flags |= B_ERROR; 1009 bp->b_error = error; 1010 } 1011 } else if (bp->b_flags & B_READ) { 1012 io.iov_len = uiop->uio_resid = bp->b_bcount; 1013 io.iov_base = bp->b_data; 1014 uiop->uio_rw = UIO_READ; 1015 switch (vp->v_type) { 1016 case VREG: 1017 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1018 nfsstats.read_bios++; 1019 error = nfs_readrpc(vp, uiop, cr); 1020 if (!error) { 1021 bp->b_validoff = 0; 1022 if (uiop->uio_resid) { 1023 /* 1024 * If len > 0, there is a hole in the file and 1025 * no writes after the hole have been pushed to 1026 * the server yet. 1027 * Just zero fill the rest of the valid area. 1028 */ 1029 diff = bp->b_bcount - uiop->uio_resid; 1030 len = np->n_size - (((u_quad_t)bp->b_blkno) * DEV_BSIZE 1031 + diff); 1032 if (len > 0) { 1033 len = min(len, uiop->uio_resid); 1034 memset((char *)bp->b_data + diff, 0, len); 1035 bp->b_validend = diff + len; 1036 } else 1037 bp->b_validend = diff; 1038 } else 1039 bp->b_validend = bp->b_bcount; 1040 } 1041 if (p && (vp->v_flag & VTEXT) && 1042 (((nmp->nm_flag & NFSMNT_NQNFS) && 1043 NQNFS_CKINVALID(vp, np, ND_READ) && 1044 np->n_lrev != np->n_brev) || 1045 (!(nmp->nm_flag & NFSMNT_NQNFS) && 1046 np->n_mtime != np->n_vattr->va_mtime.tv_sec))) { 1047 uprintf("Process killed due to text file modification\n"); 1048 psignal(p, SIGKILL); 1049 p->p_holdcnt++; 1050 } 1051 break; 1052 case VLNK: 1053 uiop->uio_offset = (off_t)0; 1054 nfsstats.readlink_bios++; 1055 error = nfs_readlinkrpc(vp, uiop, cr); 1056 break; 1057 case VDIR: 1058 nfsstats.readdir_bios++; 1059 uiop->uio_offset = bp->b_dcookie; 1060 if (nmp->nm_flag & NFSMNT_RDIRPLUS) { 1061 error = nfs_readdirplusrpc(vp, uiop, cr); 1062 if (error == NFSERR_NOTSUPP) 1063 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 1064 } 1065 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 1066 error = nfs_readdirrpc(vp, uiop, cr); 1067 if (!error) { 1068 bp->b_dcookie = uiop->uio_offset; 1069 bp->b_validoff = 0; 1070 bp->b_validend = bp->b_bcount - uiop->uio_resid; 1071 } 1072 break; 1073 default: 1074 printf("nfs_doio: type %x unexpected\n",vp->v_type); 1075 break; 1076 }; 1077 if (error) { 1078 bp->b_flags |= B_ERROR; 1079 bp->b_error = error; 1080 } 1081 } else { 1082 io.iov_len = uiop->uio_resid = bp->b_dirtyend 1083 - bp->b_dirtyoff; 1084 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE 1085 + bp->b_dirtyoff; 1086 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 1087 uiop->uio_rw = UIO_WRITE; 1088 nfsstats.write_bios++; 1089 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE)) == B_ASYNC) 1090 iomode = NFSV3WRITE_UNSTABLE; 1091 else 1092 iomode = NFSV3WRITE_FILESYNC; 1093 bp->b_flags |= B_WRITEINPROG; 1094 #ifdef fvdl_debug 1095 printf("nfs_doio(%x): bp %x doff %d dend %d\n", 1096 vp, bp, bp->b_dirtyoff, bp->b_dirtyend); 1097 #endif 1098 error = nfs_writerpc(vp, uiop, cr, &iomode, &must_commit); 1099 if (!error && iomode == NFSV3WRITE_UNSTABLE) 1100 bp->b_flags |= B_NEEDCOMMIT; 1101 else 1102 bp->b_flags &= ~B_NEEDCOMMIT; 1103 bp->b_flags &= ~B_WRITEINPROG; 1104 1105 /* 1106 * For an interrupted write, the buffer is still valid and the 1107 * write hasn't been pushed to the server yet, so we can't set 1108 * B_ERROR and report the interruption by setting B_EINTR. For 1109 * the B_ASYNC case, B_EINTR is not relevant, so the rpc attempt 1110 * is essentially a noop. 1111 * For the case of a V3 write rpc not being committed to stable 1112 * storage, the block is still dirty and requires either a commit 1113 * rpc or another write rpc with iomode == NFSV3WRITE_FILESYNC 1114 * before the block is reused. This is indicated by setting the 1115 * B_DELWRI and B_NEEDCOMMIT flags. 1116 */ 1117 if (error == EINTR || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 1118 bp->b_flags |= B_DELWRI; 1119 1120 /* 1121 * Since for the B_ASYNC case, nfs_bwrite() has reassigned the 1122 * buffer to the clean list, we have to reassign it back to the 1123 * dirty one. Ugh. 1124 */ 1125 if (bp->b_flags & B_ASYNC) 1126 reassignbuf(bp, vp); 1127 else if (error) 1128 bp->b_flags |= B_EINTR; 1129 } else { 1130 if (error) { 1131 bp->b_flags |= B_ERROR; 1132 bp->b_error = np->n_error = error; 1133 np->n_flag |= NWRITEERR; 1134 } 1135 bp->b_dirtyoff = bp->b_dirtyend = 0; 1136 } 1137 } 1138 bp->b_resid = uiop->uio_resid; 1139 if (must_commit) 1140 nfs_clearcommit(vp->v_mount); 1141 biodone(bp); 1142 return (error); 1143 } 1144
Indexes created Tue Oct 14 11:09:46 GMT 2025