nfs_bio.c revision 36979
1/* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Rick Macklem at The University of Guelph. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95 37 * $Id: nfs_bio.c,v 1.58 1998/06/01 11:32:53 peter Exp $ 38 */ 39 40 41#include <sys/param.h> 42#include <sys/systm.h> 43#include <sys/resourcevar.h> 44#include <sys/signalvar.h> 45#include <sys/proc.h> 46#include <sys/buf.h> 47#include <sys/vnode.h> 48#include <sys/mount.h> 49#include <sys/kernel.h> 50 51#include <vm/vm.h> 52#include <vm/vm_extern.h> 53#include <vm/vm_prot.h> 54#include <vm/vm_page.h> 55#include <vm/vm_object.h> 56#include <vm/vm_pager.h> 57#include <vm/vnode_pager.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 66static struct buf *nfs_getcacheblk __P((struct vnode *vp, daddr_t bn, int size, 67 struct proc *p)); 68static void nfs_prot_buf __P((struct buf *bp, int off, int n)); 69 70extern int nfs_numasync; 71extern struct nfsstats nfsstats; 72 73/* 74 * Vnode op for VM getpages. 75 */ 76int 77nfs_getpages(ap) 78 struct vop_getpages_args /* { 79 struct vnode *a_vp; 80 vm_page_t *a_m; 81 int a_count; 82 int a_reqpage; 83 vm_ooffset_t a_offset; 84 } */ *ap; 85{ 86 int i, error, nextoff, size, toff, npages, count; 87 struct uio uio; 88 struct iovec iov; 89 vm_page_t m; 90 vm_offset_t kva; 91 struct buf *bp; 92 struct vnode *vp; 93 struct proc *p; 94 struct ucred *cred; 95 struct nfsmount *nmp; 96 vm_page_t *pages; 97 98 vp = ap->a_vp; 99 p = curproc; /* XXX */ 100 cred = curproc->p_ucred; /* XXX */ 101 nmp = VFSTONFS(vp->v_mount); 102 pages = ap->a_m; 103 count = ap->a_count; 104 105 if (vp->v_object == NULL) { 106 printf("nfs_getpages: called with non-merged cache vnode??\n"); 107 return VM_PAGER_ERROR; 108 } 109 110 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 111 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) 112 (void)nfs_fsinfo(nmp, vp, cred, p); 113 /* 114 * We use only the kva address for the buffer, but this is extremely 115 * convienient and fast. 116 */ 117 bp = getpbuf(); 118 119 npages = btoc(count); 120 kva = (vm_offset_t) bp->b_data; 121 pmap_qenter(kva, pages, npages); 122 123 iov.iov_base = (caddr_t) kva; 124 iov.iov_len = count; 125 uio.uio_iov = &iov; 126 uio.uio_iovcnt = 1; 127 uio.uio_offset = IDX_TO_OFF(pages[0]->pindex); 128 uio.uio_resid = count; 129 uio.uio_segflg = UIO_SYSSPACE; 130 uio.uio_rw = UIO_READ; 131 uio.uio_procp = p; 132 133 error = nfs_readrpc(vp, &uio, cred); 134 pmap_qremove(kva, npages); 135 136 relpbuf(bp); 137 138 if (error && (uio.uio_resid == count)) 139 return VM_PAGER_ERROR; 140 141 size = count - uio.uio_resid; 142 143 for (i = 0, toff = 0; i < npages; i++, toff = nextoff) { 144 vm_page_t m; 145 nextoff = toff + PAGE_SIZE; 146 m = pages[i]; 147 148 m->flags &= ~PG_ZERO; 149 150 if (nextoff <= size) { 151 m->valid = VM_PAGE_BITS_ALL; 152 m->dirty = 0; 153 } else { 154 int nvalid = ((size + DEV_BSIZE - 1) - toff) & ~(DEV_BSIZE - 1); 155 vm_page_set_validclean(m, 0, nvalid); 156 } 157 158 if (i != ap->a_reqpage) { 159 /* 160 * Whether or not to leave the page activated is up in 161 * the air, but we should put the page on a page queue 162 * somewhere (it already is in the object). Result: 163 * It appears that emperical results show that 164 * deactivating pages is best. 165 */ 166 167 /* 168 * Just in case someone was asking for this page we 169 * now tell them that it is ok to use. 170 */ 171 if (!error) { 172 if (m->flags & PG_WANTED) 173 vm_page_activate(m); 174 else 175 vm_page_deactivate(m); 176 PAGE_WAKEUP(m); 177 } else { 178 vnode_pager_freepage(m); 179 } 180 } 181 } 182 return 0; 183} 184 185/* 186 * Vnode op for VM putpages. 187 */ 188int 189nfs_putpages(ap) 190 struct vop_putpages_args /* { 191 struct vnode *a_vp; 192 vm_page_t *a_m; 193 int a_count; 194 int a_sync; 195 int *a_rtvals; 196 vm_ooffset_t a_offset; 197 } */ *ap; 198{ 199 struct uio uio; 200 struct iovec iov; 201 vm_page_t m; 202 vm_offset_t kva; 203 struct buf *bp; 204 int iomode, must_commit, i, error, npages, count; 205 int *rtvals; 206 struct vnode *vp; 207 struct proc *p; 208 struct ucred *cred; 209 struct nfsmount *nmp; 210 vm_page_t *pages; 211 212 vp = ap->a_vp; 213 p = curproc; /* XXX */ 214 cred = curproc->p_ucred; /* XXX */ 215 nmp = VFSTONFS(vp->v_mount); 216 pages = ap->a_m; 217 count = ap->a_count; 218 rtvals = ap->a_rtvals; 219 npages = btoc(count); 220 221 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 222 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) 223 (void)nfs_fsinfo(nmp, vp, cred, p); 224 225 for (i = 0; i < npages; i++) { 226 rtvals[i] = VM_PAGER_AGAIN; 227 } 228 229 /* 230 * We use only the kva address for the buffer, but this is extremely 231 * convienient and fast. 232 */ 233 bp = getpbuf(); 234 235 kva = (vm_offset_t) bp->b_data; 236 pmap_qenter(kva, pages, npages); 237 238 iov.iov_base = (caddr_t) kva; 239 iov.iov_len = count; 240 uio.uio_iov = &iov; 241 uio.uio_iovcnt = 1; 242 uio.uio_offset = IDX_TO_OFF(pages[0]->pindex); 243 uio.uio_resid = count; 244 uio.uio_segflg = UIO_SYSSPACE; 245 uio.uio_rw = UIO_WRITE; 246 uio.uio_procp = p; 247 248 if ((ap->a_sync & VM_PAGER_PUT_SYNC) == 0) 249 iomode = NFSV3WRITE_UNSTABLE; 250 else 251 iomode = NFSV3WRITE_FILESYNC; 252 253 error = nfs_writerpc(vp, &uio, cred, &iomode, &must_commit); 254 255 pmap_qremove(kva, npages); 256 relpbuf(bp); 257 258 if (!error) { 259 int nwritten = round_page(count - uio.uio_resid) / PAGE_SIZE; 260 for (i = 0; i < nwritten; i++) { 261 rtvals[i] = VM_PAGER_OK; 262 pages[i]->dirty = 0; 263 } 264 if (must_commit) 265 nfs_clearcommit(vp->v_mount); 266 } 267 return rtvals[0]; 268} 269 270/* 271 * Vnode op for read using bio 272 */ 273int 274nfs_bioread(vp, uio, ioflag, cred, getpages) 275 register struct vnode *vp; 276 register struct uio *uio; 277 int ioflag; 278 struct ucred *cred; 279 int getpages; 280{ 281 register struct nfsnode *np = VTONFS(vp); 282 register int biosize, diff, i; 283 struct buf *bp = 0, *rabp; 284 struct vattr vattr; 285 struct proc *p; 286 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 287 daddr_t lbn, rabn; 288 int bufsize; 289 int nra, error = 0, n = 0, on = 0, not_readin; 290 291#ifdef DIAGNOSTIC 292 if (uio->uio_rw != UIO_READ) 293 panic("nfs_read mode"); 294#endif 295 if (uio->uio_resid == 0) 296 return (0); 297 if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */ 298 return (EINVAL); 299 p = uio->uio_procp; 300 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 301 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) 302 (void)nfs_fsinfo(nmp, vp, cred, p); 303 if (vp->v_type != VDIR && 304 (uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 305 return (EFBIG); 306 biosize = vp->v_mount->mnt_stat.f_iosize; 307 /* 308 * For nfs, cache consistency can only be maintained approximately. 309 * Although RFC1094 does not specify the criteria, the following is 310 * believed to be compatible with the reference port. 311 * For nqnfs, full cache consistency is maintained within the loop. 312 * For nfs: 313 * If the file's modify time on the server has changed since the 314 * last read rpc or you have written to the file, 315 * you may have lost data cache consistency with the 316 * server, so flush all of the file's data out of the cache. 317 * Then force a getattr rpc to ensure that you have up to date 318 * attributes. 319 * NB: This implies that cache data can be read when up to 320 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 321 * attributes this could be forced by setting n_attrstamp to 0 before 322 * the VOP_GETATTR() call. 323 */ 324 if ((nmp->nm_flag & NFSMNT_NQNFS) == 0) { 325 if (np->n_flag & NMODIFIED) { 326 if (vp->v_type != VREG) { 327 if (vp->v_type != VDIR) 328 panic("nfs: bioread, not dir"); 329 nfs_invaldir(vp); 330 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 331 if (error) 332 return (error); 333 } 334 np->n_attrstamp = 0; 335 error = VOP_GETATTR(vp, &vattr, cred, p); 336 if (error) 337 return (error); 338 np->n_mtime = vattr.va_mtime.tv_sec; 339 } else { 340 error = VOP_GETATTR(vp, &vattr, cred, p); 341 if (error) 342 return (error); 343 if (np->n_mtime != vattr.va_mtime.tv_sec) { 344 if (vp->v_type == VDIR) 345 nfs_invaldir(vp); 346 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 347 if (error) 348 return (error); 349 np->n_mtime = vattr.va_mtime.tv_sec; 350 } 351 } 352 } 353 do { 354 355 /* 356 * Get a valid lease. If cached data is stale, flush it. 357 */ 358 if (nmp->nm_flag & NFSMNT_NQNFS) { 359 if (NQNFS_CKINVALID(vp, np, ND_READ)) { 360 do { 361 error = nqnfs_getlease(vp, ND_READ, cred, p); 362 } while (error == NQNFS_EXPIRED); 363 if (error) 364 return (error); 365 if (np->n_lrev != np->n_brev || 366 (np->n_flag & NQNFSNONCACHE) || 367 ((np->n_flag & NMODIFIED) && vp->v_type == VDIR)) { 368 if (vp->v_type == VDIR) 369 nfs_invaldir(vp); 370 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 371 if (error) 372 return (error); 373 np->n_brev = np->n_lrev; 374 } 375 } else if (vp->v_type == VDIR && (np->n_flag & NMODIFIED)) { 376 nfs_invaldir(vp); 377 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 378 if (error) 379 return (error); 380 } 381 } 382 if (np->n_flag & NQNFSNONCACHE) { 383 switch (vp->v_type) { 384 case VREG: 385 return (nfs_readrpc(vp, uio, cred)); 386 case VLNK: 387 return (nfs_readlinkrpc(vp, uio, cred)); 388 case VDIR: 389 break; 390 default: 391 printf(" NQNFSNONCACHE: type %x unexpected\n", 392 vp->v_type); 393 }; 394 } 395 switch (vp->v_type) { 396 case VREG: 397 nfsstats.biocache_reads++; 398 lbn = uio->uio_offset / biosize; 399 on = uio->uio_offset & (biosize - 1); 400 not_readin = 1; 401 402 /* 403 * Start the read ahead(s), as required. 404 */ 405 if (nfs_numasync > 0 && nmp->nm_readahead > 0) { 406 for (nra = 0; nra < nmp->nm_readahead && 407 (off_t)(lbn + 1 + nra) * biosize < np->n_size; nra++) { 408 rabn = lbn + 1 + nra; 409 if (!incore(vp, rabn)) { 410 rabp = nfs_getcacheblk(vp, rabn, biosize, p); 411 if (!rabp) 412 return (EINTR); 413 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 414 rabp->b_flags |= (B_READ | B_ASYNC); 415 vfs_busy_pages(rabp, 0); 416 if (nfs_asyncio(rabp, cred)) { 417 rabp->b_flags |= B_INVAL|B_ERROR; 418 vfs_unbusy_pages(rabp); 419 brelse(rabp); 420 } 421 } else 422 brelse(rabp); 423 } 424 } 425 } 426 427 /* 428 * If the block is in the cache and has the required data 429 * in a valid region, just copy it out. 430 * Otherwise, get the block and write back/read in, 431 * as required. 432 */ 433again: 434 bufsize = biosize; 435 if ((off_t)(lbn + 1) * biosize > np->n_size && 436 (off_t)(lbn + 1) * biosize - np->n_size < biosize) { 437 bufsize = np->n_size - lbn * biosize; 438 bufsize = (bufsize + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1); 439 } 440 bp = nfs_getcacheblk(vp, lbn, bufsize, p); 441 if (!bp) 442 return (EINTR); 443 /* 444 * If we are being called from nfs_getpages, we must 445 * make sure the buffer is a vmio buffer. The vp will 446 * already be setup for vmio but there may be some old 447 * non-vmio buffers attached to it. 448 */ 449 if (getpages && !(bp->b_flags & B_VMIO)) { 450#ifdef DIAGNOSTIC 451 printf("nfs_bioread: non vmio buf found, discarding\n"); 452#endif 453 bp->b_flags |= B_NOCACHE; 454 bp->b_flags |= B_INVAFTERWRITE; 455 if (bp->b_dirtyend > 0) { 456 if ((bp->b_flags & B_DELWRI) == 0) 457 panic("nfsbioread"); 458 if (VOP_BWRITE(bp) == EINTR) 459 return (EINTR); 460 } else 461 brelse(bp); 462 goto again; 463 } 464 if ((bp->b_flags & B_CACHE) == 0) { 465 bp->b_flags |= B_READ; 466 bp->b_flags &= ~(B_DONE | B_ERROR | B_INVAL); 467 not_readin = 0; 468 vfs_busy_pages(bp, 0); 469 error = nfs_doio(bp, cred, p); 470 if (error) { 471 brelse(bp); 472 return (error); 473 } 474 } 475 if (bufsize > on) { 476 n = min((unsigned)(bufsize - on), uio->uio_resid); 477 } else { 478 n = 0; 479 } 480 diff = np->n_size - uio->uio_offset; 481 if (diff < n) 482 n = diff; 483 if (not_readin && n > 0) { 484 if (on < bp->b_validoff || (on + n) > bp->b_validend) { 485 bp->b_flags |= B_NOCACHE; 486 bp->b_flags |= B_INVAFTERWRITE; 487 if (bp->b_dirtyend > 0) { 488 if ((bp->b_flags & B_DELWRI) == 0) 489 panic("nfsbioread"); 490 if (VOP_BWRITE(bp) == EINTR) 491 return (EINTR); 492 } else 493 brelse(bp); 494 goto again; 495 } 496 } 497 vp->v_lastr = lbn; 498 diff = (on >= bp->b_validend) ? 0 : (bp->b_validend - on); 499 if (diff < n) 500 n = diff; 501 break; 502 case VLNK: 503 nfsstats.biocache_readlinks++; 504 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, p); 505 if (!bp) 506 return (EINTR); 507 if ((bp->b_flags & B_CACHE) == 0) { 508 bp->b_flags |= B_READ; 509 vfs_busy_pages(bp, 0); 510 error = nfs_doio(bp, cred, p); 511 if (error) { 512 bp->b_flags |= B_ERROR; 513 brelse(bp); 514 return (error); 515 } 516 } 517 n = min(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 518 on = 0; 519 break; 520 case VDIR: 521 nfsstats.biocache_readdirs++; 522 if (np->n_direofoffset 523 && uio->uio_offset >= np->n_direofoffset) { 524 return (0); 525 } 526 lbn = (uoff_t)uio->uio_offset / NFS_DIRBLKSIZ; 527 on = uio->uio_offset & (NFS_DIRBLKSIZ - 1); 528 bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, p); 529 if (!bp) 530 return (EINTR); 531 if ((bp->b_flags & B_CACHE) == 0) { 532 bp->b_flags |= B_READ; 533 vfs_busy_pages(bp, 0); 534 error = nfs_doio(bp, cred, p); 535 if (error) { 536 brelse(bp); 537 } 538 while (error == NFSERR_BAD_COOKIE) { 539 nfs_invaldir(vp); 540 error = nfs_vinvalbuf(vp, 0, cred, p, 1); 541 /* 542 * Yuck! The directory has been modified on the 543 * server. The only way to get the block is by 544 * reading from the beginning to get all the 545 * offset cookies. 546 */ 547 for (i = 0; i <= lbn && !error; i++) { 548 if (np->n_direofoffset 549 && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset) 550 return (0); 551 bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, p); 552 if (!bp) 553 return (EINTR); 554 if ((bp->b_flags & B_DONE) == 0) { 555 bp->b_flags |= B_READ; 556 vfs_busy_pages(bp, 0); 557 error = nfs_doio(bp, cred, p); 558 if (error) { 559 brelse(bp); 560 } else if (i < lbn) { 561 brelse(bp); 562 } 563 } 564 } 565 } 566 if (error) 567 return (error); 568 } 569 570 /* 571 * If not eof and read aheads are enabled, start one. 572 * (You need the current block first, so that you have the 573 * directory offset cookie of the next block.) 574 */ 575 if (nfs_numasync > 0 && nmp->nm_readahead > 0 && 576 (np->n_direofoffset == 0 || 577 (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) && 578 !(np->n_flag & NQNFSNONCACHE) && 579 !incore(vp, lbn + 1)) { 580 rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, p); 581 if (rabp) { 582 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 583 rabp->b_flags |= (B_READ | B_ASYNC); 584 vfs_busy_pages(rabp, 0); 585 if (nfs_asyncio(rabp, cred)) { 586 rabp->b_flags |= B_INVAL|B_ERROR; 587 vfs_unbusy_pages(rabp); 588 brelse(rabp); 589 } 590 } else { 591 brelse(rabp); 592 } 593 } 594 } 595 /* 596 * Make sure we use a signed variant of min() since 597 * the second term may be negative. 598 */ 599 n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on); 600 break; 601 default: 602 printf(" nfs_bioread: type %x unexpected\n",vp->v_type); 603 break; 604 }; 605 606 if (n > 0) { 607 error = uiomove(bp->b_data + on, (int)n, uio); 608 } 609 switch (vp->v_type) { 610 case VREG: 611 break; 612 case VLNK: 613 n = 0; 614 break; 615 case VDIR: 616 if (np->n_flag & NQNFSNONCACHE) 617 bp->b_flags |= B_INVAL; 618 break; 619 default: 620 printf(" nfs_bioread: type %x unexpected\n",vp->v_type); 621 } 622 brelse(bp); 623 } while (error == 0 && uio->uio_resid > 0 && n > 0); 624 return (error); 625} 626 627static void 628nfs_prot_buf(bp, off, n) 629 struct buf *bp; 630 int off; 631 int n; 632{ 633 int pindex, boff, end; 634 635 if ((bp->b_flags & B_VMIO) == 0) 636 return; 637 638 end = round_page(off + n); 639 for (boff = trunc_page(off); boff < end; boff += PAGE_SIZE) { 640 pindex = boff >> PAGE_SHIFT; 641 vm_page_protect(bp->b_pages[pindex], VM_PROT_NONE); 642 } 643} 644 645/* 646 * Vnode op for write using bio 647 */ 648int 649nfs_write(ap) 650 struct vop_write_args /* { 651 struct vnode *a_vp; 652 struct uio *a_uio; 653 int a_ioflag; 654 struct ucred *a_cred; 655 } */ *ap; 656{ 657 register int biosize; 658 register struct uio *uio = ap->a_uio; 659 struct proc *p = uio->uio_procp; 660 register struct vnode *vp = ap->a_vp; 661 struct nfsnode *np = VTONFS(vp); 662 register struct ucred *cred = ap->a_cred; 663 int ioflag = ap->a_ioflag; 664 struct buf *bp; 665 struct vattr vattr; 666 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 667 daddr_t lbn; 668 int bufsize; 669 int n, on, error = 0, iomode, must_commit; 670 671#ifdef DIAGNOSTIC 672 if (uio->uio_rw != UIO_WRITE) 673 panic("nfs_write mode"); 674 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) 675 panic("nfs_write proc"); 676#endif 677 if (vp->v_type != VREG) 678 return (EIO); 679 if (np->n_flag & NWRITEERR) { 680 np->n_flag &= ~NWRITEERR; 681 return (np->n_error); 682 } 683 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 684 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) 685 (void)nfs_fsinfo(nmp, vp, cred, p); 686 if (ioflag & (IO_APPEND | IO_SYNC)) { 687 if (np->n_flag & NMODIFIED) { 688 np->n_attrstamp = 0; 689 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 690 if (error) 691 return (error); 692 } 693 if (ioflag & IO_APPEND) { 694 np->n_attrstamp = 0; 695 error = VOP_GETATTR(vp, &vattr, cred, p); 696 if (error) 697 return (error); 698 uio->uio_offset = np->n_size; 699 } 700 } 701 if (uio->uio_offset < 0) 702 return (EINVAL); 703 if ((uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 704 return (EFBIG); 705 if (uio->uio_resid == 0) 706 return (0); 707 /* 708 * Maybe this should be above the vnode op call, but so long as 709 * file servers have no limits, i don't think it matters 710 */ 711 if (p && uio->uio_offset + uio->uio_resid > 712 p->p_rlimit[RLIMIT_FSIZE].rlim_cur) { 713 psignal(p, SIGXFSZ); 714 return (EFBIG); 715 } 716 /* 717 * I use nm_rsize, not nm_wsize so that all buffer cache blocks 718 * will be the same size within a filesystem. nfs_writerpc will 719 * still use nm_wsize when sizing the rpc's. 720 */ 721 biosize = vp->v_mount->mnt_stat.f_iosize; 722 do { 723 /* 724 * Check for a valid write lease. 725 */ 726 if ((nmp->nm_flag & NFSMNT_NQNFS) && 727 NQNFS_CKINVALID(vp, np, ND_WRITE)) { 728 do { 729 error = nqnfs_getlease(vp, ND_WRITE, cred, p); 730 } while (error == NQNFS_EXPIRED); 731 if (error) 732 return (error); 733 if (np->n_lrev != np->n_brev || 734 (np->n_flag & NQNFSNONCACHE)) { 735 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 736 if (error) 737 return (error); 738 np->n_brev = np->n_lrev; 739 } 740 } 741 if ((np->n_flag & NQNFSNONCACHE) && uio->uio_iovcnt == 1) { 742 iomode = NFSV3WRITE_FILESYNC; 743 error = nfs_writerpc(vp, uio, cred, &iomode, &must_commit); 744 if (must_commit) 745 nfs_clearcommit(vp->v_mount); 746 return (error); 747 } 748 nfsstats.biocache_writes++; 749 lbn = uio->uio_offset / biosize; 750 on = uio->uio_offset & (biosize-1); 751 n = min((unsigned)(biosize - on), uio->uio_resid); 752again: 753 if (uio->uio_offset + n > np->n_size) { 754 np->n_size = uio->uio_offset + n; 755 np->n_flag |= NMODIFIED; 756 vnode_pager_setsize(vp, (u_long)np->n_size); 757 } 758 bufsize = biosize; 759 if ((lbn + 1) * biosize > np->n_size) { 760 bufsize = np->n_size - lbn * biosize; 761 bufsize = (bufsize + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1); 762 } 763 bp = nfs_getcacheblk(vp, lbn, bufsize, p); 764 if (!bp) 765 return (EINTR); 766 if (bp->b_wcred == NOCRED) { 767 crhold(cred); 768 bp->b_wcred = cred; 769 } 770 np->n_flag |= NMODIFIED; 771 772 if ((bp->b_blkno * DEV_BSIZE) + bp->b_dirtyend > np->n_size) { 773 bp->b_dirtyend = np->n_size - (bp->b_blkno * DEV_BSIZE); 774 } 775 776 /* 777 * If the new write will leave a contiguous dirty 778 * area, just update the b_dirtyoff and b_dirtyend, 779 * otherwise force a write rpc of the old dirty area. 780 */ 781 if (bp->b_dirtyend > 0 && 782 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 783 bp->b_proc = p; 784 if (VOP_BWRITE(bp) == EINTR) 785 return (EINTR); 786 goto again; 787 } 788 789 /* 790 * Check for valid write lease and get one as required. 791 * In case getblk() and/or bwrite() delayed us. 792 */ 793 if ((nmp->nm_flag & NFSMNT_NQNFS) && 794 NQNFS_CKINVALID(vp, np, ND_WRITE)) { 795 do { 796 error = nqnfs_getlease(vp, ND_WRITE, cred, p); 797 } while (error == NQNFS_EXPIRED); 798 if (error) { 799 brelse(bp); 800 return (error); 801 } 802 if (np->n_lrev != np->n_brev || 803 (np->n_flag & NQNFSNONCACHE)) { 804 brelse(bp); 805 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 806 if (error) 807 return (error); 808 np->n_brev = np->n_lrev; 809 goto again; 810 } 811 } 812 813 error = uiomove((char *)bp->b_data + on, n, uio); 814 if (error) { 815 bp->b_flags |= B_ERROR; 816 brelse(bp); 817 return (error); 818 } 819 820 /* 821 * This will keep the buffer and mmaped regions more coherent. 822 */ 823 nfs_prot_buf(bp, on, n); 824 825 if (bp->b_dirtyend > 0) { 826 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 827 bp->b_dirtyend = max((on + n), bp->b_dirtyend); 828 } else { 829 bp->b_dirtyoff = on; 830 bp->b_dirtyend = on + n; 831 } 832 if (bp->b_validend == 0 || bp->b_validend < bp->b_dirtyoff || 833 bp->b_validoff > bp->b_dirtyend) { 834 bp->b_validoff = bp->b_dirtyoff; 835 bp->b_validend = bp->b_dirtyend; 836 } else { 837 bp->b_validoff = min(bp->b_validoff, bp->b_dirtyoff); 838 bp->b_validend = max(bp->b_validend, bp->b_dirtyend); 839 } 840 841 /* 842 * Since this block is being modified, it must be written 843 * again and not just committed. 844 */ 845 bp->b_flags &= ~B_NEEDCOMMIT; 846 847 /* 848 * If the lease is non-cachable or IO_SYNC do bwrite(). 849 */ 850 if ((np->n_flag & NQNFSNONCACHE) || (ioflag & IO_SYNC)) { 851 bp->b_proc = p; 852 if (ioflag & IO_INVAL) 853 bp->b_flags |= B_INVAL; 854 error = VOP_BWRITE(bp); 855 if (error) 856 return (error); 857 if (np->n_flag & NQNFSNONCACHE) { 858 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); 859 if (error) 860 return (error); 861 } 862 } else if ((n + on) == biosize && 863 (nmp->nm_flag & NFSMNT_NQNFS) == 0) { 864 bp->b_proc = (struct proc *)0; 865 bp->b_flags |= B_ASYNC; 866 (void)nfs_writebp(bp, 0); 867 } else 868 bdwrite(bp); 869 } while (uio->uio_resid > 0 && n > 0); 870 return (0); 871} 872 873/* 874 * Get an nfs cache block. 875 * Allocate a new one if the block isn't currently in the cache 876 * and return the block marked busy. If the calling process is 877 * interrupted by a signal for an interruptible mount point, return 878 * NULL. 879 */ 880static struct buf * 881nfs_getcacheblk(vp, bn, size, p) 882 struct vnode *vp; 883 daddr_t bn; 884 int size; 885 struct proc *p; 886{ 887 register struct buf *bp; 888 struct mount *mp; 889 struct nfsmount *nmp; 890 891 mp = vp->v_mount; 892 nmp = VFSTONFS(mp); 893 894 if (nmp->nm_flag & NFSMNT_INT) { 895 bp = getblk(vp, bn, size, PCATCH, 0); 896 while (bp == (struct buf *)0) { 897 if (nfs_sigintr(nmp, (struct nfsreq *)0, p)) 898 return ((struct buf *)0); 899 bp = getblk(vp, bn, size, 0, 2 * hz); 900 } 901 } else 902 bp = getblk(vp, bn, size, 0, 0); 903 904 if( vp->v_type == VREG) { 905 int biosize; 906 biosize = mp->mnt_stat.f_iosize; 907 bp->b_blkno = (bn * biosize) / DEV_BSIZE; 908 } 909 910 return (bp); 911} 912 913/* 914 * Flush and invalidate all dirty buffers. If another process is already 915 * doing the flush, just wait for completion. 916 */ 917int 918nfs_vinvalbuf(vp, flags, cred, p, intrflg) 919 struct vnode *vp; 920 int flags; 921 struct ucred *cred; 922 struct proc *p; 923 int intrflg; 924{ 925 register struct nfsnode *np = VTONFS(vp); 926 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 927 int error = 0, slpflag, slptimeo; 928 929 if (vp->v_flag & VXLOCK) { 930 return (0); 931 } 932 933 if ((nmp->nm_flag & NFSMNT_INT) == 0) 934 intrflg = 0; 935 if (intrflg) { 936 slpflag = PCATCH; 937 slptimeo = 2 * hz; 938 } else { 939 slpflag = 0; 940 slptimeo = 0; 941 } 942 /* 943 * First wait for any other process doing a flush to complete. 944 */ 945 while (np->n_flag & NFLUSHINPROG) { 946 np->n_flag |= NFLUSHWANT; 947 error = tsleep((caddr_t)&np->n_flag, PRIBIO + 2, "nfsvinval", 948 slptimeo); 949 if (error && intrflg && nfs_sigintr(nmp, (struct nfsreq *)0, p)) 950 return (EINTR); 951 } 952 953 /* 954 * Now, flush as required. 955 */ 956 np->n_flag |= NFLUSHINPROG; 957 error = vinvalbuf(vp, flags, cred, p, slpflag, 0); 958 while (error) { 959 if (intrflg && nfs_sigintr(nmp, (struct nfsreq *)0, p)) { 960 np->n_flag &= ~NFLUSHINPROG; 961 if (np->n_flag & NFLUSHWANT) { 962 np->n_flag &= ~NFLUSHWANT; 963 wakeup((caddr_t)&np->n_flag); 964 } 965 return (EINTR); 966 } 967 error = vinvalbuf(vp, flags, cred, p, 0, slptimeo); 968 } 969 np->n_flag &= ~(NMODIFIED | NFLUSHINPROG); 970 if (np->n_flag & NFLUSHWANT) { 971 np->n_flag &= ~NFLUSHWANT; 972 wakeup((caddr_t)&np->n_flag); 973 } 974 return (0); 975} 976 977/* 978 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 979 * This is mainly to avoid queueing async I/O requests when the nfsiods 980 * are all hung on a dead server. 981 */ 982int 983nfs_asyncio(bp, cred) 984 register struct buf *bp; 985 struct ucred *cred; 986{ 987 struct nfsmount *nmp; 988 int i; 989 int gotiod; 990 int slpflag = 0; 991 int slptimeo = 0; 992 int error; 993 994 if (nfs_numasync == 0) 995 return (EIO); 996 997 nmp = VFSTONFS(bp->b_vp->v_mount); 998again: 999 if (nmp->nm_flag & NFSMNT_INT) 1000 slpflag = PCATCH; 1001 gotiod = FALSE; 1002 1003 /* 1004 * Find a free iod to process this request. 1005 */ 1006 for (i = 0; i < NFS_MAXASYNCDAEMON; i++) 1007 if (nfs_iodwant[i]) { 1008 /* 1009 * Found one, so wake it up and tell it which 1010 * mount to process. 1011 */ 1012 NFS_DPF(ASYNCIO, 1013 ("nfs_asyncio: waking iod %d for mount %p\n", 1014 i, nmp)); 1015 nfs_iodwant[i] = (struct proc *)0; 1016 nfs_iodmount[i] = nmp; 1017 nmp->nm_bufqiods++; 1018 wakeup((caddr_t)&nfs_iodwant[i]); 1019 gotiod = TRUE; 1020 break; 1021 } 1022 1023 /* 1024 * If none are free, we may already have an iod working on this mount 1025 * point. If so, it will process our request. 1026 */ 1027 if (!gotiod) { 1028 if (nmp->nm_bufqiods > 0) { 1029 NFS_DPF(ASYNCIO, 1030 ("nfs_asyncio: %d iods are already processing mount %p\n", 1031 nmp->nm_bufqiods, nmp)); 1032 gotiod = TRUE; 1033 } 1034 } 1035 1036 /* 1037 * If we have an iod which can process the request, then queue 1038 * the buffer. 1039 */ 1040 if (gotiod) { 1041 /* 1042 * Ensure that the queue never grows too large. 1043 */ 1044 while (nmp->nm_bufqlen >= 2*nfs_numasync) { 1045 NFS_DPF(ASYNCIO, 1046 ("nfs_asyncio: waiting for mount %p queue to drain\n", nmp)); 1047 nmp->nm_bufqwant = TRUE; 1048 error = tsleep(&nmp->nm_bufq, slpflag | PRIBIO, 1049 "nfsaio", slptimeo); 1050 if (error) { 1051 if (nfs_sigintr(nmp, NULL, bp->b_proc)) 1052 return (EINTR); 1053 if (slpflag == PCATCH) { 1054 slpflag = 0; 1055 slptimeo = 2 * hz; 1056 } 1057 } 1058 /* 1059 * We might have lost our iod while sleeping, 1060 * so check and loop if nescessary. 1061 */ 1062 if (nmp->nm_bufqiods == 0) { 1063 NFS_DPF(ASYNCIO, 1064 ("nfs_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); 1065 goto again; 1066 } 1067 } 1068 1069 if (bp->b_flags & B_READ) { 1070 if (bp->b_rcred == NOCRED && cred != NOCRED) { 1071 crhold(cred); 1072 bp->b_rcred = cred; 1073 } 1074 } else { 1075 bp->b_flags |= B_WRITEINPROG; 1076 if (bp->b_wcred == NOCRED && cred != NOCRED) { 1077 crhold(cred); 1078 bp->b_wcred = cred; 1079 } 1080 } 1081 1082 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 1083 nmp->nm_bufqlen++; 1084 return (0); 1085 } 1086 1087 /* 1088 * All the iods are busy on other mounts, so return EIO to 1089 * force the caller to process the i/o synchronously. 1090 */ 1091 NFS_DPF(ASYNCIO, ("nfs_asyncio: no iods available, i/o is synchronous\n")); 1092 return (EIO); 1093} 1094 1095/* 1096 * Do an I/O operation to/from a cache block. This may be called 1097 * synchronously or from an nfsiod. 1098 */ 1099int 1100nfs_doio(bp, cr, p) 1101 register struct buf *bp; 1102 struct ucred *cr; 1103 struct proc *p; 1104{ 1105 register struct uio *uiop; 1106 register struct vnode *vp; 1107 struct nfsnode *np; 1108 struct nfsmount *nmp; 1109 int error = 0, diff, len, iomode, must_commit = 0; 1110 struct uio uio; 1111 struct iovec io; 1112 1113 vp = bp->b_vp; 1114 np = VTONFS(vp); 1115 nmp = VFSTONFS(vp->v_mount); 1116 uiop = &uio; 1117 uiop->uio_iov = &io; 1118 uiop->uio_iovcnt = 1; 1119 uiop->uio_segflg = UIO_SYSSPACE; 1120 uiop->uio_procp = p; 1121 1122 /* 1123 * Historically, paging was done with physio, but no more. 1124 */ 1125 if (bp->b_flags & B_PHYS) { 1126 /* 1127 * ...though reading /dev/drum still gets us here. 1128 */ 1129 io.iov_len = uiop->uio_resid = bp->b_bcount; 1130 /* mapping was done by vmapbuf() */ 1131 io.iov_base = bp->b_data; 1132 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1133 if (bp->b_flags & B_READ) { 1134 uiop->uio_rw = UIO_READ; 1135 nfsstats.read_physios++; 1136 error = nfs_readrpc(vp, uiop, cr); 1137 } else { 1138 int com; 1139 1140 iomode = NFSV3WRITE_DATASYNC; 1141 uiop->uio_rw = UIO_WRITE; 1142 nfsstats.write_physios++; 1143 error = nfs_writerpc(vp, uiop, cr, &iomode, &com); 1144 } 1145 if (error) { 1146 bp->b_flags |= B_ERROR; 1147 bp->b_error = error; 1148 } 1149 } else if (bp->b_flags & B_READ) { 1150 io.iov_len = uiop->uio_resid = bp->b_bcount; 1151 io.iov_base = bp->b_data; 1152 uiop->uio_rw = UIO_READ; 1153 switch (vp->v_type) { 1154 case VREG: 1155 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1156 nfsstats.read_bios++; 1157 error = nfs_readrpc(vp, uiop, cr); 1158 if (!error) { 1159 bp->b_validoff = 0; 1160 if (uiop->uio_resid) { 1161 /* 1162 * If len > 0, there is a hole in the file and 1163 * no writes after the hole have been pushed to 1164 * the server yet. 1165 * Just zero fill the rest of the valid area. 1166 */ 1167 diff = bp->b_bcount - uiop->uio_resid; 1168 len = np->n_size - (((u_quad_t)bp->b_blkno) * DEV_BSIZE 1169 + diff); 1170 if (len > 0) { 1171 len = min(len, uiop->uio_resid); 1172 bzero((char *)bp->b_data + diff, len); 1173 bp->b_validend = diff + len; 1174 } else 1175 bp->b_validend = diff; 1176 } else 1177 bp->b_validend = bp->b_bcount; 1178 } 1179 if (p && (vp->v_flag & VTEXT) && 1180 (((nmp->nm_flag & NFSMNT_NQNFS) && 1181 NQNFS_CKINVALID(vp, np, ND_READ) && 1182 np->n_lrev != np->n_brev) || 1183 (!(nmp->nm_flag & NFSMNT_NQNFS) && 1184 np->n_mtime != np->n_vattr.va_mtime.tv_sec))) { 1185 uprintf("Process killed due to text file modification\n"); 1186 psignal(p, SIGKILL); 1187 p->p_flag |= P_NOSWAP; 1188 } 1189 break; 1190 case VLNK: 1191 uiop->uio_offset = (off_t)0; 1192 nfsstats.readlink_bios++; 1193 error = nfs_readlinkrpc(vp, uiop, cr); 1194 break; 1195 case VDIR: 1196 nfsstats.readdir_bios++; 1197 uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ; 1198 if (nmp->nm_flag & NFSMNT_RDIRPLUS) { 1199 error = nfs_readdirplusrpc(vp, uiop, cr); 1200 if (error == NFSERR_NOTSUPP) 1201 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 1202 } 1203 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 1204 error = nfs_readdirrpc(vp, uiop, cr); 1205 break; 1206 default: 1207 printf("nfs_doio: type %x unexpected\n",vp->v_type); 1208 break; 1209 }; 1210 if (error) { 1211 bp->b_flags |= B_ERROR; 1212 bp->b_error = error; 1213 } 1214 } else { 1215 if (((bp->b_blkno * DEV_BSIZE) + bp->b_dirtyend) > np->n_size) 1216 bp->b_dirtyend = np->n_size - (bp->b_blkno * DEV_BSIZE); 1217 1218 if (bp->b_dirtyend > bp->b_dirtyoff) { 1219 io.iov_len = uiop->uio_resid = bp->b_dirtyend 1220 - bp->b_dirtyoff; 1221 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE 1222 + bp->b_dirtyoff; 1223 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 1224 uiop->uio_rw = UIO_WRITE; 1225 nfsstats.write_bios++; 1226 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC) 1227 iomode = NFSV3WRITE_UNSTABLE; 1228 else 1229 iomode = NFSV3WRITE_FILESYNC; 1230 bp->b_flags |= B_WRITEINPROG; 1231 error = nfs_writerpc(vp, uiop, cr, &iomode, &must_commit); 1232 if (!error && iomode == NFSV3WRITE_UNSTABLE) { 1233 bp->b_flags |= B_NEEDCOMMIT; 1234 if (bp->b_dirtyoff == 0 1235 && bp->b_dirtyend == bp->b_bufsize) 1236 bp->b_flags |= B_CLUSTEROK; 1237 } else 1238 bp->b_flags &= ~B_NEEDCOMMIT; 1239 bp->b_flags &= ~B_WRITEINPROG; 1240 1241 /* 1242 * For an interrupted write, the buffer is still valid 1243 * and the write hasn't been pushed to the server yet, 1244 * so we can't set B_ERROR and report the interruption 1245 * by setting B_EINTR. For the B_ASYNC case, B_EINTR 1246 * is not relevant, so the rpc attempt is essentially 1247 * a noop. For the case of a V3 write rpc not being 1248 * committed to stable storage, the block is still 1249 * dirty and requires either a commit rpc or another 1250 * write rpc with iomode == NFSV3WRITE_FILESYNC before 1251 * the block is reused. This is indicated by setting 1252 * the B_DELWRI and B_NEEDCOMMIT flags. 1253 */ 1254 if (error == EINTR 1255 || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 1256 int s; 1257 1258 bp->b_flags &= ~(B_INVAL|B_NOCACHE); 1259 ++numdirtybuffers; 1260 bp->b_flags |= B_DELWRI; 1261 s = splbio(); 1262 reassignbuf(bp, vp); 1263 splx(s); 1264 if ((bp->b_flags & B_ASYNC) == 0) 1265 bp->b_flags |= B_EINTR; 1266 } else { 1267 if (error) { 1268 bp->b_flags |= B_ERROR; 1269 bp->b_error = np->n_error = error; 1270 np->n_flag |= NWRITEERR; 1271 } 1272 bp->b_dirtyoff = bp->b_dirtyend = 0; 1273 } 1274 } else { 1275 bp->b_resid = 0; 1276 biodone(bp); 1277 return (0); 1278 } 1279 } 1280 bp->b_resid = uiop->uio_resid; 1281 if (must_commit) 1282 nfs_clearcommit(vp->v_mount); 1283 biodone(bp); 1284 return (error); 1285} 1286